Volume 0,Issue 3,2013 Table of Contents
2013(3):1-5.
Abstract:
The relationship between the pan evaporation and climatic factors is the important basis to characterize of the effects of climate change on hydrological cycle. Based on the measured meteorological data from in the Ejina mMeteorological sStation from 1961 to 2001, thea Penpan model was developedcalibrated and to reflect the relationship between the pan evaporation and four related climatic variables was obtainedin the Ejina Delta and to estimate the pan evaporation from 2002 to 2011. Therefore, the variations of Changes of pan evaporation and four related climatic variables were analyzed and their effects on the pan evaporation were analyzed during the period from 1961 to 2011 in the Ejina Delta. The pan evaporation change was attributed by analyzing its sensitivity to the related climatic variables. The results showed that: (1) pan evaporation presented a significant negative decreasing trend and itswith a rate of rate was -215.5 mm·10a-1, while. Mmean temperature presented an increasing positive trend. In addition, however wind speed, total radiation, and relative humidity presented negative decreasing trends;. (2) Generally, pan evaporation was most sensitive to wind speed, followed by relative humidity, total radiation, and mean temperature. The sensitivities of pan evaporation to wind speed and relative humidity presented negative trendsdecreased while, however the sensitivities to total radiation and mean temperature presented positive trendsincreased during the period from 1961 to 2011;. and (3) the variation of wWind speed had thecontributed most contribution to the change variation of pan evaporation, followed by relative humidity, mean temperature, and total radiation.
The relationship between the pan evaporation and climatic factors is the important basis to characterize of the effects of climate change on hydrological cycle. Based on the measured meteorological data from in the Ejina mMeteorological sStation from 1961 to 2001, thea Penpan model was developedcalibrated and to reflect the relationship between the pan evaporation and four related climatic variables was obtainedin the Ejina Delta and to estimate the pan evaporation from 2002 to 2011. Therefore, the variations of Changes of pan evaporation and four related climatic variables were analyzed and their effects on the pan evaporation were analyzed during the period from 1961 to 2011 in the Ejina Delta. The pan evaporation change was attributed by analyzing its sensitivity to the related climatic variables. The results showed that: (1) pan evaporation presented a significant negative decreasing trend and itswith a rate of rate was -215.5 mm·10a-1, while. Mmean temperature presented an increasing positive trend. In addition, however wind speed, total radiation, and relative humidity presented negative decreasing trends;. (2) Generally, pan evaporation was most sensitive to wind speed, followed by relative humidity, total radiation, and mean temperature. The sensitivities of pan evaporation to wind speed and relative humidity presented negative trendsdecreased while, however the sensitivities to total radiation and mean temperature presented positive trendsincreased during the period from 1961 to 2011;. and (3) the variation of wWind speed had thecontributed most contribution to the change variation of pan evaporation, followed by relative humidity, mean temperature, and total radiation.
2013(3):6-11.
Abstract:
According to the national and local allocation proportions of water resources in the Yellow River, the irrigation water amount drawn from the Yellow River will be limited to less than 4.0 × 109 m3 per year in the future for the Hetao Irrigation District while the current irrigation water amount is about 5.2 × 109 m3 per year. With the decreasing of the irrigation water amount and rapid economic development, the conflict between the supply and demand of water resources can be more serious, therefore the reasonable utilization of the limited water resources is the primary task faced by the local authority in the Hetao Irrigation District. Based on the analysis of current supply and demand balance of water resources and the long-term plans and water resources utilization in the irrigation district, two schemes of conjunctive use of irrigation water from the Yellow River and groundwater are developed. Moreover, the optimization analysis is conducted on the conjunctive use of water resources in the planning year and the dynamic variations of groundwater under different schemes are simulated. The results show that the irrigation water of 4.0 × 109 m3 per year can maintain the sustainable development of the irrigation district under the conditions of optimizing the industrial structure, enlarging the combined well-canal irrigation areas, and using the groundwater resources including brackish water effectively.
According to the national and local allocation proportions of water resources in the Yellow River, the irrigation water amount drawn from the Yellow River will be limited to less than 4.0 × 109 m3 per year in the future for the Hetao Irrigation District while the current irrigation water amount is about 5.2 × 109 m3 per year. With the decreasing of the irrigation water amount and rapid economic development, the conflict between the supply and demand of water resources can be more serious, therefore the reasonable utilization of the limited water resources is the primary task faced by the local authority in the Hetao Irrigation District. Based on the analysis of current supply and demand balance of water resources and the long-term plans and water resources utilization in the irrigation district, two schemes of conjunctive use of irrigation water from the Yellow River and groundwater are developed. Moreover, the optimization analysis is conducted on the conjunctive use of water resources in the planning year and the dynamic variations of groundwater under different schemes are simulated. The results show that the irrigation water of 4.0 × 109 m3 per year can maintain the sustainable development of the irrigation district under the conditions of optimizing the industrial structure, enlarging the combined well-canal irrigation areas, and using the groundwater resources including brackish water effectively.
2013(3):12-16.
Abstract:
With the increasing of urbanization and the rapid economic development, the rural water resources protection has more and more problems. In this paper, an evaluation index system of rural water resources protection in Hunan province was developed using the grey correlation degree approach based on the optimal combination weight method, and this evaluation index system was applied to investigate the status of rural water resources protection in Hunan province in 2010. .The results showed that four indexes are the most relevant factors with rural water resources protection, including the vegetation coverage, the completeness and implementation of policies, the effective irrigation rate, and the average fertilizer application rate per hectare. Finally, the improved model of GM(1.1) was used to predicate the variation trends of ten main indexes from 2011 to 2016. Model test parameters reached the qualified levels. The predicted results can offer decision-making references for rural water resources protection.
With the increasing of urbanization and the rapid economic development, the rural water resources protection has more and more problems. In this paper, an evaluation index system of rural water resources protection in Hunan province was developed using the grey correlation degree approach based on the optimal combination weight method, and this evaluation index system was applied to investigate the status of rural water resources protection in Hunan province in 2010. .The results showed that four indexes are the most relevant factors with rural water resources protection, including the vegetation coverage, the completeness and implementation of policies, the effective irrigation rate, and the average fertilizer application rate per hectare. Finally, the improved model of GM(1.1) was used to predicate the variation trends of ten main indexes from 2011 to 2016. Model test parameters reached the qualified levels. The predicted results can offer decision-making references for rural water resources protection.
2013(3):17-20.
Abstract:
Huaisha River is one of the input rivers to the Beitaishang Reservior. As an emergency water source in Beijing, the hydrological regime in this river watershed plays an important role in the safeguard of water supply. In this paper, NAM hydrological model was used to simulate the rainfall-runoff process in the Huaisha River Watershed with a set of calibrated parameters. The research results indicated that the simulated and observed flow process curves match very well, and the simulation precision NSE (Nash- Sutcliffe coefficient of efficiency) is 0.642. This model was used to analyze the local rainstorm-flood process and flood distribution in the Huaisha River Watershed, which indicated that the maximum discharge at the outlet of the watershed is 30.8 m3/s, similar to the observed maximum discharge of 31.0 m3/s at the Xigou hydrological station.
Huaisha River is one of the input rivers to the Beitaishang Reservior. As an emergency water source in Beijing, the hydrological regime in this river watershed plays an important role in the safeguard of water supply. In this paper, NAM hydrological model was used to simulate the rainfall-runoff process in the Huaisha River Watershed with a set of calibrated parameters. The research results indicated that the simulated and observed flow process curves match very well, and the simulation precision NSE (Nash- Sutcliffe coefficient of efficiency) is 0.642. This model was used to analyze the local rainstorm-flood process and flood distribution in the Huaisha River Watershed, which indicated that the maximum discharge at the outlet of the watershed is 30.8 m3/s, similar to the observed maximum discharge of 31.0 m3/s at the Xigou hydrological station.
2013(3):21-26.
Abstract:
The Mann-Kendall method was used to analyze the trend variations and mutations of annual average temperature and precipitation based on the meteorological data of Xinmi City from 1971 to 2000. The anthropogenic driving forces affecting the variations of temperature and precipitation were determined by the socio-economic data collected from 1981 to 2008. The gray relational analysis was used to characterize the interannual variability of impact strength of human activities and the temporal variations of anthropogenic driving factors before and after the temperature mutation. , and therefore the anthropogenic driving factors affecting the climate change can be analyzed and identified. The results indicated that the annual and seasonal atmospheric temperatures increase with a temperature mutation in 1993 while the annual precipitation has significant increasing or decreasing trends. The rapid growth of population density is the primary driving force of the temperature change in Xinmi, and followed by the agricultural development and energy consumption.
The Mann-Kendall method was used to analyze the trend variations and mutations of annual average temperature and precipitation based on the meteorological data of Xinmi City from 1971 to 2000. The anthropogenic driving forces affecting the variations of temperature and precipitation were determined by the socio-economic data collected from 1981 to 2008. The gray relational analysis was used to characterize the interannual variability of impact strength of human activities and the temporal variations of anthropogenic driving factors before and after the temperature mutation. , and therefore the anthropogenic driving factors affecting the climate change can be analyzed and identified. The results indicated that the annual and seasonal atmospheric temperatures increase with a temperature mutation in 1993 while the annual precipitation has significant increasing or decreasing trends. The rapid growth of population density is the primary driving force of the temperature change in Xinmi, and followed by the agricultural development and energy consumption.
6 Experimental Study on Non-point Source Pollution of Main Farmlands in the Chaihe Reservoir Watershed
2013(3):27-30.
Abstract:
In order to investigate the characteristics of non-point source pollution from three kinds of farmlands, including rice field, corn field, and seedlings field, a series of rainfall-runoff experiments were conducted in the three experimental fields of the Chaihe Reservoir Watershed with close location and similar soil type. The yield characteristics and impact factors of non-point source pollution from these fields were analyzed using the rainfall and runoff data from the monitoring rainfall events. The results showed that the event mean concentrations (EMCs) of different land use fields vary under the same rainfall conditions, and the EMCs of the same land use field can also be quite different under different rainfall conditions. Land use type, precipitation characteristics, and fertilizer application play important roles in affecting the non-point source pollution.
In order to investigate the characteristics of non-point source pollution from three kinds of farmlands, including rice field, corn field, and seedlings field, a series of rainfall-runoff experiments were conducted in the three experimental fields of the Chaihe Reservoir Watershed with close location and similar soil type. The yield characteristics and impact factors of non-point source pollution from these fields were analyzed using the rainfall and runoff data from the monitoring rainfall events. The results showed that the event mean concentrations (EMCs) of different land use fields vary under the same rainfall conditions, and the EMCs of the same land use field can also be quite different under different rainfall conditions. Land use type, precipitation characteristics, and fertilizer application play important roles in affecting the non-point source pollution.
2013(3):31-34.
Abstract:
In this paper, the bank protection mechanism and effects of plant technology were introduced. A mathematical model was developed to analyze the soil reinforcement by the plant root system and the reductions of flow drag force and scouring around spur dike by the above-ground parts of plant based on a flood control construction (spur dike) located in the downstream reach of Zhang River at Chengcun. The results showed that although the effective flow drag force near the soil of spur dike increases with the increasing of flow rate after the planting, the increment decreases, which indicated that the reduction function of the plants increases with the increasing of flow rate. Moreover, the study concluded that the scour depth of the flood control construction (spur dike) reduced by 40 to 126 cm in the range of studied flow rates.
In this paper, the bank protection mechanism and effects of plant technology were introduced. A mathematical model was developed to analyze the soil reinforcement by the plant root system and the reductions of flow drag force and scouring around spur dike by the above-ground parts of plant based on a flood control construction (spur dike) located in the downstream reach of Zhang River at Chengcun. The results showed that although the effective flow drag force near the soil of spur dike increases with the increasing of flow rate after the planting, the increment decreases, which indicated that the reduction function of the plants increases with the increasing of flow rate. Moreover, the study concluded that the scour depth of the flood control construction (spur dike) reduced by 40 to 126 cm in the range of studied flow rates.
2013(3):35-38.
Abstract:
The granular activated carbon, powdered activated carbon, and activated carbon-loaded chitosan were used in the static adsorption experiment of high Mn groundwater, and the granular activated carbon was used in the dynamic adsorption experiment of high Mn groundwater, which can determine the effects of adsorbent dosage, pH value, and temperature on the adsorption efficacy under the static conditions and the effects of Mn2+ concentration and flow velocity on the adsorption efficacy under the dynamic conditions. The results showed that the adsorption efficacy is similar for the three adsorbents with the powered activated carbon having a relatively better adsorption efficacy. Under the static conditions with the Mn2+ concentration of 5 mg/L, temperature of 25 o C, and pH value of 6.8~7.0, the granular activated carbon had the best adsorption efficacy and the best dosage was 0.02 g/L, i.e. 0.4g ( GAC ) /mg ( Mn2+ ). Under the dynamic conditions，the increasing of Mn2+ concentration and flow velocity can advance the initial penetration point．
The granular activated carbon, powdered activated carbon, and activated carbon-loaded chitosan were used in the static adsorption experiment of high Mn groundwater, and the granular activated carbon was used in the dynamic adsorption experiment of high Mn groundwater, which can determine the effects of adsorbent dosage, pH value, and temperature on the adsorption efficacy under the static conditions and the effects of Mn2+ concentration and flow velocity on the adsorption efficacy under the dynamic conditions. The results showed that the adsorption efficacy is similar for the three adsorbents with the powered activated carbon having a relatively better adsorption efficacy. Under the static conditions with the Mn2+ concentration of 5 mg/L, temperature of 25 o C, and pH value of 6.8~7.0, the granular activated carbon had the best adsorption efficacy and the best dosage was 0.02 g/L, i.e. 0.4g ( GAC ) /mg ( Mn2+ ). Under the dynamic conditions，the increasing of Mn2+ concentration and flow velocity can advance the initial penetration point．
2013(3):39-41.
Abstract:
Zhenlai County of Jilin Province is located in the farming-pastoral ecotone in northern China. As a commodity grain base, agricultural development is an important activity in this area. In order to investigate the current ecological and environmental conditions, the feature of resource consumption, and the pressure shift of external resources in the farming-pastoral ecotone in the study area, the ecological footprint method was used to analyze the biological resource production and energy consumption data in 2010 of Zhenlai County. The results showed that agriculture and animal husbandry developments are the primary resource consumers in Zhenlai County. Most of the farming and pasturing products were sold to other places; therefore this area sustained a huge pressure shift of external resources and the ecological deficit occurred in Zhenlai Country. A further analysis indicated that the increasing of agricultural acreage to solve the problems of low yield and single cropping to promote the agricultural production can occupy other land use types, which can disturb the ecological environment significantly and aggravate the degradation of ecological environment in Zhenlai
Zhenlai County of Jilin Province is located in the farming-pastoral ecotone in northern China. As a commodity grain base, agricultural development is an important activity in this area. In order to investigate the current ecological and environmental conditions, the feature of resource consumption, and the pressure shift of external resources in the farming-pastoral ecotone in the study area, the ecological footprint method was used to analyze the biological resource production and energy consumption data in 2010 of Zhenlai County. The results showed that agriculture and animal husbandry developments are the primary resource consumers in Zhenlai County. Most of the farming and pasturing products were sold to other places; therefore this area sustained a huge pressure shift of external resources and the ecological deficit occurred in Zhenlai Country. A further analysis indicated that the increasing of agricultural acreage to solve the problems of low yield and single cropping to promote the agricultural production can occupy other land use types, which can disturb the ecological environment significantly and aggravate the degradation of ecological environment in Zhenlai
2013(3):42-46.
Abstract:
Based on the connotation of the river function and the natural characteristics of the river itself，a river function evaluation index system was developed in consideration of the taking natural function，ecological environment function, and social service function of the river into account and the domestic and international research on river function evaluation. This evaluation index system contained 18 indexes, which can provide the evaluation standard of river function. ，referencing domestic and foreign research of the rivers function evaluation，following the scientific，practical，concise evaluation principles，this paper constructs a river function evaluation index system containing 18 specific indicators，which creatively proposes the evaluation standard of river function． In this paper, the The proposed evaluation indexesdicators，criteria, and methods wereare applied to verify the function access of the Baitiao River, and the evaluation results tallied with the actual situations of the Baitiao River.
Based on the connotation of the river function and the natural characteristics of the river itself，a river function evaluation index system was developed in consideration of the taking natural function，ecological environment function, and social service function of the river into account and the domestic and international research on river function evaluation. This evaluation index system contained 18 indexes, which can provide the evaluation standard of river function. ，referencing domestic and foreign research of the rivers function evaluation，following the scientific，practical，concise evaluation principles，this paper constructs a river function evaluation index system containing 18 specific indicators，which creatively proposes the evaluation standard of river function． In this paper, the The proposed evaluation indexesdicators，criteria, and methods wereare applied to verify the function access of the Baitiao River, and the evaluation results tallied with the actual situations of the Baitiao River.
2013(3):47-51.
Abstract:
Water environment is the basic environment for the social and economic development and is a complex system for human survival and development. Moreover, it is the most vulnerable to the disturbance and destruction of human activities. In recent years, the rapid development of industrialization and urbanization of Hainan Province has resulted in different degrees of pollution in the water environment. At the same time, with the development of Hainan as an International Tourism Island, the demand for fresh water has increased dramatically due to the increasing of visitors, which will lead to significant impacts on the water environmental carrying capacity of Hainan Province. In this paper, the water environmental carrying capacity of Hainan Province was analyzed using the combined method of Analytic Hierarchy Process (AHP) and “mode and sum”. The results showed that the water environmental carrying capacity of Hainan Province has increased gradually from 2005 to 2010, but it was in a weak level and the state of water environment was very fragile. Through the analysis of the current situation of water environment of Hainan Province, the measures to maintain and enhance the water environmental carrying capacity of Hainan Province were proposed.
Water environment is the basic environment for the social and economic development and is a complex system for human survival and development. Moreover, it is the most vulnerable to the disturbance and destruction of human activities. In recent years, the rapid development of industrialization and urbanization of Hainan Province has resulted in different degrees of pollution in the water environment. At the same time, with the development of Hainan as an International Tourism Island, the demand for fresh water has increased dramatically due to the increasing of visitors, which will lead to significant impacts on the water environmental carrying capacity of Hainan Province. In this paper, the water environmental carrying capacity of Hainan Province was analyzed using the combined method of Analytic Hierarchy Process (AHP) and “mode and sum”. The results showed that the water environmental carrying capacity of Hainan Province has increased gradually from 2005 to 2010, but it was in a weak level and the state of water environment was very fragile. Through the analysis of the current situation of water environment of Hainan Province, the measures to maintain and enhance the water environmental carrying capacity of Hainan Province were proposed.
2013(3):52-56.
Abstract:
An evaluation index system was developed based on the reuse approaches and quality of reclaimed water from Jizhuangzi reclaimed wastewater treatment plant in Tianjin, and this index system can be used to performed the risk assessment of the reclaimed water from the landscape water and surface water. The environmental risks for the use of reclaimed water under different conditions were obtained, which can provide a better evaluation of the environmental risks of utilization of reclaimed water. The risk assessment index system of urban reclaimed water (including the health risk index and ecological environmental risk index) can provide references for the evaluation of reuse of urban reclaimed water.
An evaluation index system was developed based on the reuse approaches and quality of reclaimed water from Jizhuangzi reclaimed wastewater treatment plant in Tianjin, and this index system can be used to performed the risk assessment of the reclaimed water from the landscape water and surface water. The environmental risks for the use of reclaimed water under different conditions were obtained, which can provide a better evaluation of the environmental risks of utilization of reclaimed water. The risk assessment index system of urban reclaimed water (including the health risk index and ecological environmental risk index) can provide references for the evaluation of reuse of urban reclaimed water.
2013(3):57-61.
Abstract:
In this study, the WET soil moisture meter (hereinafter referred to as WET) was applied for the first time to investigate the ECp (pore water conductivity) of soils in the northern Yinchuan plain, and to evaluate the distribution characteristics of soil salinization in this area. The results showed that only a small part of the northern Yinchuan plain has non-saline soil and other parts have saline soils, especially in the central part of Huinong area, Huangquqiao and Lingsha of Pingluo area, and the north part of Helan area where the soil has very high salinity. The research results from this study were consistent with those from previous studies. Therefore, with little changes in the water contents and soil pH values, the application of WET-based method on the soil salinization is accurate and reliable technically.
In this study, the WET soil moisture meter (hereinafter referred to as WET) was applied for the first time to investigate the ECp (pore water conductivity) of soils in the northern Yinchuan plain, and to evaluate the distribution characteristics of soil salinization in this area. The results showed that only a small part of the northern Yinchuan plain has non-saline soil and other parts have saline soils, especially in the central part of Huinong area, Huangquqiao and Lingsha of Pingluo area, and the north part of Helan area where the soil has very high salinity. The research results from this study were consistent with those from previous studies. Therefore, with little changes in the water contents and soil pH values, the application of WET-based method on the soil salinization is accurate and reliable technically.
2013(3):62-66.
Abstract:
The cavity length in the aerator is an important indicator for aeration effects. It is impacted by many factors, including the aerator shape (height and slope), hydraulic conditions, negative pressure in the cavity, and air resistance. In this paper, the physical model experiments were conducted to study the effects of chute slope and aerator shape on the cavity length under the conditions of slight slope. Furthermore, the relationships between the cavity length and each of the three factors, namely Froude number (Fr), Reynolds number (Re), and Weber number (We), were obtained, and the reason of the experiment results that the cavity length fluctuates with the Froude number (Fr) under the conditions of slight slope was analyzed. Finally, the cavity length was calculated using Yang Yong-sen’s formula, and the errors and correlations between the calculated and experimental values were analyzed. These results can provide references for optimizing the aerator design and improving the empirical calculation formulas.
The cavity length in the aerator is an important indicator for aeration effects. It is impacted by many factors, including the aerator shape (height and slope), hydraulic conditions, negative pressure in the cavity, and air resistance. In this paper, the physical model experiments were conducted to study the effects of chute slope and aerator shape on the cavity length under the conditions of slight slope. Furthermore, the relationships between the cavity length and each of the three factors, namely Froude number (Fr), Reynolds number (Re), and Weber number (We), were obtained, and the reason of the experiment results that the cavity length fluctuates with the Froude number (Fr) under the conditions of slight slope was analyzed. Finally, the cavity length was calculated using Yang Yong-sen’s formula, and the errors and correlations between the calculated and experimental values were analyzed. These results can provide references for optimizing the aerator design and improving the empirical calculation formulas.
2013(3):67-70.
Abstract:
The soil dilatancy angles of the stratified slopes with different layers, different materials, and different heights were reduced to analyze the effects of soil dilatancy angle on the stability of stratified slope using the strength reduction method and finite element software ABAQUS. The results showed that when the soil dilatancy angle decreased for any soil layer, the safety factor Fs increased with the increasing of dilatancy angle while the increment decreased gradually and the safety factor was not affected by the soil material, height, number of layers. The dilatancy angle of a single soil layer had lower effects on the safety factor Fs compared with the overall slope, and the dilatancy angle of the upper soil layer of the slope had higher effects on the stability of the stratified slope. With the increasing of dilatancy angle, the displacement trend of the slope became obvious with an expanding range of plastic zone and an increasing sliding arc radius and safety factor . In practical engineering, it is better to reduce the soil dilatancy angle of the slope to a carefully selected value .
The soil dilatancy angles of the stratified slopes with different layers, different materials, and different heights were reduced to analyze the effects of soil dilatancy angle on the stability of stratified slope using the strength reduction method and finite element software ABAQUS. The results showed that when the soil dilatancy angle decreased for any soil layer, the safety factor Fs increased with the increasing of dilatancy angle while the increment decreased gradually and the safety factor was not affected by the soil material, height, number of layers. The dilatancy angle of a single soil layer had lower effects on the safety factor Fs compared with the overall slope, and the dilatancy angle of the upper soil layer of the slope had higher effects on the stability of the stratified slope. With the increasing of dilatancy angle, the displacement trend of the slope became obvious with an expanding range of plastic zone and an increasing sliding arc radius and safety factor . In practical engineering, it is better to reduce the soil dilatancy angle of the slope to a carefully selected value .
2013(3):71-75.
Abstract:
The software FLAC3D based on the nonlinear finite difference method was used to obtain the position of potential sliding surface of the high stilling pool slope in a hydropower station. A block system analysis model was developed based on the discontinuous deformation analysis (DDA)This model was used to analyze the relationship between the displacement and strength parameter of the current slope and reinforced slope, which provided the ultimate internal friction angle and the corresponding stability safety factor of the slope before and after reinforcement. The results showed that the slope has a relatively smaller safety factor and is likely to be instable before reinforcement. After the reinforcement with the prestressed anchor cable, the safety factor of the slope increased significantly to meet the requirements of normal operation.
The software FLAC3D based on the nonlinear finite difference method was used to obtain the position of potential sliding surface of the high stilling pool slope in a hydropower station. A block system analysis model was developed based on the discontinuous deformation analysis (DDA)This model was used to analyze the relationship between the displacement and strength parameter of the current slope and reinforced slope, which provided the ultimate internal friction angle and the corresponding stability safety factor of the slope before and after reinforcement. The results showed that the slope has a relatively smaller safety factor and is likely to be instable before reinforcement. After the reinforcement with the prestressed anchor cable, the safety factor of the slope increased significantly to meet the requirements of normal operation.
2013(3):76-81.
Abstract:
The three-dimensional finite element analysis method was used to simulate the dynamic characteristics and dynamic response of two units in the main powerhouse of the pumped storage power station. According to analysis results of the natural vibration frequency of the whole powerhouse structure, natural vibration frequency of the partial structures, and the staggered degree of main vibration frequency of the powerhouse, resonance does not occur for the whole structure of powerhouse, and the severe vibration of the powerhouse is caused by the resonance of the partial support components under the excitation frequency of vibration source. With the comparative analysis of vibration acceleration distribution patterns obtained from the field tests and the time history response of the finite element model, the main hydraulic vibration source stimulating the powerhouse vibration is the pressure pulsation between the rotor and the vanes. The frequency of pressure pulsation (100 Hz) is twice of the blade overcurrent frequency. The analysis of the vibration causes of the pumped storage power station can provide references for the anti-vibration check during the design stage and vibration cause analysis during the operation period of the pumped storage power station.
The three-dimensional finite element analysis method was used to simulate the dynamic characteristics and dynamic response of two units in the main powerhouse of the pumped storage power station. According to analysis results of the natural vibration frequency of the whole powerhouse structure, natural vibration frequency of the partial structures, and the staggered degree of main vibration frequency of the powerhouse, resonance does not occur for the whole structure of powerhouse, and the severe vibration of the powerhouse is caused by the resonance of the partial support components under the excitation frequency of vibration source. With the comparative analysis of vibration acceleration distribution patterns obtained from the field tests and the time history response of the finite element model, the main hydraulic vibration source stimulating the powerhouse vibration is the pressure pulsation between the rotor and the vanes. The frequency of pressure pulsation (100 Hz) is twice of the blade overcurrent frequency. The analysis of the vibration causes of the pumped storage power station can provide references for the anti-vibration check during the design stage and vibration cause analysis during the operation period of the pumped storage power station.
2013(3):82-85.
Abstract:
PUR-revetment is a newly developed method for hydraulic engineering application. Its structure is similar to that of open stone asphalt revetment, but the crushed stones are glued by polyurethane (PUR) instead of bitumen. In order to study the characteristics of applying PUR-revetment in cold regions, an experimental research of the stability of PUR-revetment under the frost heave force and ice pushing was conducted based on the prototype test conditions of ice thickness and temperature processes in the Hongqipao Reservoir of Daqing. The process curves of internal temperature, ice growing, deformation, and mechanical characteristics were analyzed to obtain the following conclusions: (1) the porous structure of PUR-revetment can result in the uniform distribution of temperature field under the revetment; (2) during the freeze-thaw cycle, a larger vertical deformation and a smaller slope deformation of PUR-revetment occur, but both deformations cannot recovery completely, thus it is necessary to take reinforcement measures at the roof support and slope foot during the designing process; and (3) the maximum ice pushing occurs during the thawing period, therefore appropriate icebreaking measures need to be performed to eliminate the effects of ice pushing on the revetment structure.
PUR-revetment is a newly developed method for hydraulic engineering application. Its structure is similar to that of open stone asphalt revetment, but the crushed stones are glued by polyurethane (PUR) instead of bitumen. In order to study the characteristics of applying PUR-revetment in cold regions, an experimental research of the stability of PUR-revetment under the frost heave force and ice pushing was conducted based on the prototype test conditions of ice thickness and temperature processes in the Hongqipao Reservoir of Daqing. The process curves of internal temperature, ice growing, deformation, and mechanical characteristics were analyzed to obtain the following conclusions: (1) the porous structure of PUR-revetment can result in the uniform distribution of temperature field under the revetment; (2) during the freeze-thaw cycle, a larger vertical deformation and a smaller slope deformation of PUR-revetment occur, but both deformations cannot recovery completely, thus it is necessary to take reinforcement measures at the roof support and slope foot during the designing process; and (3) the maximum ice pushing occurs during the thawing period, therefore appropriate icebreaking measures need to be performed to eliminate the effects of ice pushing on the revetment structure.
2013(3):86-91.
Abstract:
The phenomenon of cavitation has been found in many engineering plants. In order to investigate the viscoelastic effects of bubbles near a rigid boundary, a mathematical model and governing equation were developed based on the example of 5% polyacrylamide (PAM) water solution. The boundary integral method was used to solve the governing equation and the cubic spline function was used to characterize the bubble surface. Furthermore, the bubble dynamics phenomena were studied in this paper, including the occurrence of bubble oscillation, jet position of bubble, and the turbulence of fluid on jet velocities. The results showed that viscoelasticity of the bubble can restrain the formation of liquid jet, thereby reducing the cavitation damage.
The phenomenon of cavitation has been found in many engineering plants. In order to investigate the viscoelastic effects of bubbles near a rigid boundary, a mathematical model and governing equation were developed based on the example of 5% polyacrylamide (PAM) water solution. The boundary integral method was used to solve the governing equation and the cubic spline function was used to characterize the bubble surface. Furthermore, the bubble dynamics phenomena were studied in this paper, including the occurrence of bubble oscillation, jet position of bubble, and the turbulence of fluid on jet velocities. The results showed that viscoelasticity of the bubble can restrain the formation of liquid jet, thereby reducing the cavitation damage.
2013(3):92-96.
Abstract:
Two different techniques, pile-end post-grouting technology of bored piles and conventional cast-in-place piles, were used to conduct the in-situ static loading tests on the pile foundation of the Weihe Bridge K3+966.50 of Xi'an Xianyang International Airport Expressway. The measured data were used to analyze the interaction between the pile and soil of each pile under different loadings , the enhanced mechanism of technique, and the bearing characteristics of the two different techniques. The research results showed that the vertical ultimate bearing capacity of the pile-end post-grouting piles increases by at least 40% and the settlement decreases by about 25mm compared with that of the non-grouting piles, which suggested that the pile-end post-grouting technology can increase the bearing capacity and stability of pile foundation significantly. This paper proposed a calculation formula of the ultimate bearing capacity of a post-grouting single pile based on the observed data and grouting mechanism of pile-end post-grouting, which can provide valuable references for the pile foundation design in similar areas.
Two different techniques, pile-end post-grouting technology of bored piles and conventional cast-in-place piles, were used to conduct the in-situ static loading tests on the pile foundation of the Weihe Bridge K3+966.50 of Xi'an Xianyang International Airport Expressway. The measured data were used to analyze the interaction between the pile and soil of each pile under different loadings , the enhanced mechanism of technique, and the bearing characteristics of the two different techniques. The research results showed that the vertical ultimate bearing capacity of the pile-end post-grouting piles increases by at least 40% and the settlement decreases by about 25mm compared with that of the non-grouting piles, which suggested that the pile-end post-grouting technology can increase the bearing capacity and stability of pile foundation significantly. This paper proposed a calculation formula of the ultimate bearing capacity of a post-grouting single pile based on the observed data and grouting mechanism of pile-end post-grouting, which can provide valuable references for the pile foundation design in similar areas.
2013(3):97-100.
Abstract:
A physical model based on the background of culvert crossing the Zhang River was used to investigate the impacts of box-shaped culvert on the characteristics of water and sediment of riverbed under the conditions of once-in-three-year flood and once-in-fifty-year flood. The water levels along the river, velocities on the cross-sections in the upstream and downstream reaches of box-shaped culvert, and the local scouring in the downstream reach of box-shaped culvert were measured. The results showed that (1) under the conditions of once-in-three-year flood and once-in-fifty-year flood, there is a small amount of backwater in the upstream reach of box-shaped culvert, and the maximum heights of backwater are 0.57 m and 0.3 m, respectively; (2) the mean velocities at the cross-sections in the upstream reach of box-shaped culvert are lower than those without the culvert, and the transverse velocity distribution becomes smoother with the existence of culvert; (3) the velocity in the central of river is higher than that at the left and right river banks in the upstream face; (4) the mean velocities at the cross-section of CS8 downstream of the culvert are 1.8 m/s and 3.7m/s, respectively, which are similar to those without the culvert; and (5) under the condition of once-in-three-year flood, a stable hydraulic jump can form behind the culvert with a Froude number of 4.52, which results in low local scouring of riverbed at the cross-section of CS6 downstream of the culvert with an average scour depth of 0.5 m. The conclusions suggested that the box-shaped culvert has good hydraulic conditions.
A physical model based on the background of culvert crossing the Zhang River was used to investigate the impacts of box-shaped culvert on the characteristics of water and sediment of riverbed under the conditions of once-in-three-year flood and once-in-fifty-year flood. The water levels along the river, velocities on the cross-sections in the upstream and downstream reaches of box-shaped culvert, and the local scouring in the downstream reach of box-shaped culvert were measured. The results showed that (1) under the conditions of once-in-three-year flood and once-in-fifty-year flood, there is a small amount of backwater in the upstream reach of box-shaped culvert, and the maximum heights of backwater are 0.57 m and 0.3 m, respectively; (2) the mean velocities at the cross-sections in the upstream reach of box-shaped culvert are lower than those without the culvert, and the transverse velocity distribution becomes smoother with the existence of culvert; (3) the velocity in the central of river is higher than that at the left and right river banks in the upstream face; (4) the mean velocities at the cross-section of CS8 downstream of the culvert are 1.8 m/s and 3.7m/s, respectively, which are similar to those without the culvert; and (5) under the condition of once-in-three-year flood, a stable hydraulic jump can form behind the culvert with a Froude number of 4.52, which results in low local scouring of riverbed at the cross-section of CS6 downstream of the culvert with an average scour depth of 0.5 m. The conclusions suggested that the box-shaped culvert has good hydraulic conditions.
2013(3):101-105.
Abstract:
The flow pattern of surge chamber shared by the multi-unit hydropower plant is very complex. Determination of the hydraulic loss coefficient by the model experiments is time-consuming and expensive. In this paper, the FLUNT software was applied to conduct numerical simulation of the hydraulic resistance coefficient of a surge chamber shared by the multi-unit hydropower plant under the combined operation conditions of two typical working conditions and different number of units. The numerical simulation results were compared with those obtained from the physical model experiments, which suggested that the numerical method is feasible to determine the hydraulic resistance coefficient of a surge chamber shared by the multi-unit hydropower plant.
The flow pattern of surge chamber shared by the multi-unit hydropower plant is very complex. Determination of the hydraulic loss coefficient by the model experiments is time-consuming and expensive. In this paper, the FLUNT software was applied to conduct numerical simulation of the hydraulic resistance coefficient of a surge chamber shared by the multi-unit hydropower plant under the combined operation conditions of two typical working conditions and different number of units. The numerical simulation results were compared with those obtained from the physical model experiments, which suggested that the numerical method is feasible to determine the hydraulic resistance coefficient of a surge chamber shared by the multi-unit hydropower plant.
2013(3):106-110.
Abstract:
Based on the summary of various uses of water resources and current major water resources utilization contradictions, the harmony theory was proposed to guide the management, development, utilization, and allocation of water resources. The mathematical description method based on the harmony theory was used to evaluate and regulate the current status of water resources utilization quantitatively, and to ease the water resources utilization contradictions. The method was applied to evaluate the status of water resources utilization in Zhengzhou City, and the evaluation results were in accordance with the actual situations. According to the evaluation results, the feasible measures to solve the water resources utilization contradictions of Zhengzhou City have been proposed. Thus, the evaluation method of water resources utilization based on the harmony theory has a certain application prospects.
Based on the summary of various uses of water resources and current major water resources utilization contradictions, the harmony theory was proposed to guide the management, development, utilization, and allocation of water resources. The mathematical description method based on the harmony theory was used to evaluate and regulate the current status of water resources utilization quantitatively, and to ease the water resources utilization contradictions. The method was applied to evaluate the status of water resources utilization in Zhengzhou City, and the evaluation results were in accordance with the actual situations. According to the evaluation results, the feasible measures to solve the water resources utilization contradictions of Zhengzhou City have been proposed. Thus, the evaluation method of water resources utilization based on the harmony theory has a certain application prospects.
2013(3):111-117.
Abstract:
With the increasing impacts of human activities, the underlying surface of the river basin has encountered significant variations in recent years, which has changed the characteristics of hydrological processes such as infiltration, evapotranspiration, and runoff, and also caused significant impacts on the water resources, flood, and drought in the river basin. In order to develop the water resources reasonably, the impacts of the variations of underlying surface on the runoff yield and concentration have become a hot topic in the hydrological research. In recent years, the research process of the effects of the variations of underlying surface on the hydrological cycle can be classified into three phases: budding stage, starting stage, and development stage. The current research suggests that deforestation, grassland reclamation, agricultural development, and urbanization can increase runoff, whereas soil and water conservation can reduce runoff, and the coupling effects of landscape change and underlying surface change can impact the runoff. The research methods of the hydrological effects caused by the variations of underlying surface include the comparative test, time-series method of characteristic values, and hydrological models, and the eco-hydrological model is the frontier and hot issue of eco-hydrological research. Moreover, several comprehensive methods have been applied to investigate the hydrological effects caused by the variations of underlying surface, and the research method of “prototype observation plus numerical simulation” is the development trend.
With the increasing impacts of human activities, the underlying surface of the river basin has encountered significant variations in recent years, which has changed the characteristics of hydrological processes such as infiltration, evapotranspiration, and runoff, and also caused significant impacts on the water resources, flood, and drought in the river basin. In order to develop the water resources reasonably, the impacts of the variations of underlying surface on the runoff yield and concentration have become a hot topic in the hydrological research. In recent years, the research process of the effects of the variations of underlying surface on the hydrological cycle can be classified into three phases: budding stage, starting stage, and development stage. The current research suggests that deforestation, grassland reclamation, agricultural development, and urbanization can increase runoff, whereas soil and water conservation can reduce runoff, and the coupling effects of landscape change and underlying surface change can impact the runoff. The research methods of the hydrological effects caused by the variations of underlying surface include the comparative test, time-series method of characteristic values, and hydrological models, and the eco-hydrological model is the frontier and hot issue of eco-hydrological research. Moreover, several comprehensive methods have been applied to investigate the hydrological effects caused by the variations of underlying surface, and the research method of “prototype observation plus numerical simulation” is the development trend.
2013(3):118-122.
Abstract:
Statistical downscaling method is one of the methods that transform the meteorological data with low resolution GCMs output to the basin scale data, and this method has been studied in depth and widely used in the area of climatology. In this paper, the basic principles of the statistical downscaling method were introduced, including the basic assumptions, main steps, and key points. The statistical downscaling methods can be classified into the transfer function method, weather typing method, and weather generator model, and the applications of each method were also introduced. The uncertainty analysis of the statistical downscaling method was briefly introduced. Moreover, the future study of the statistical downscaling method should focus on its applicable conditions and range and the improvement of precision of precipitation simulation. Finally, it was pointed out that the coupling approach of statistical and dynamic downscaling methods is one of the main development directions of the downscaling study.
Statistical downscaling method is one of the methods that transform the meteorological data with low resolution GCMs output to the basin scale data, and this method has been studied in depth and widely used in the area of climatology. In this paper, the basic principles of the statistical downscaling method were introduced, including the basic assumptions, main steps, and key points. The statistical downscaling methods can be classified into the transfer function method, weather typing method, and weather generator model, and the applications of each method were also introduced. The uncertainty analysis of the statistical downscaling method was briefly introduced. Moreover, the future study of the statistical downscaling method should focus on its applicable conditions and range and the improvement of precision of precipitation simulation. Finally, it was pointed out that the coupling approach of statistical and dynamic downscaling methods is one of the main development directions of the downscaling study.
2013(3):123-126.
Abstract:
The hyporheic zone plays a key role in the surface water and groundwater interaction. Streambed hydraulic conductivity can affect the magnitude of interactions between groundwater and surface water and hyporheic water exchange. The clogging and declogging processes often occur alternately, which can change the streambed sediment characteristics and affect its permeability. On the basis of the overview of literatures of hyporheic exchange and streambed hydraulic conductivity, the possible effects of clogging and declogging processes on the streambed hydraulic conductivity have been illustrated. Streambed hydraulic conductivity is not only affected by the pore size of sediments, but also related to the hydrological connectivity and bioturbation in the hyporheic zone. Generally, the small particles brought by the floods can cause riverbed clogging, resulting in reduced hydraulic conductivity. However, when the flood goes down, hydrological exchange and bioturbation in the hyporheic zone can destroy the clogging layer, causing the declogging process and increasing in hydraulic conductivity. The current studies are limited to the analysis of the variations of measured streambed hydraulic conductivity data, and the mechanism of the clogging and declogging processes in the hyporheic zone of a river requires more investigations.
The hyporheic zone plays a key role in the surface water and groundwater interaction. Streambed hydraulic conductivity can affect the magnitude of interactions between groundwater and surface water and hyporheic water exchange. The clogging and declogging processes often occur alternately, which can change the streambed sediment characteristics and affect its permeability. On the basis of the overview of literatures of hyporheic exchange and streambed hydraulic conductivity, the possible effects of clogging and declogging processes on the streambed hydraulic conductivity have been illustrated. Streambed hydraulic conductivity is not only affected by the pore size of sediments, but also related to the hydrological connectivity and bioturbation in the hyporheic zone. Generally, the small particles brought by the floods can cause riverbed clogging, resulting in reduced hydraulic conductivity. However, when the flood goes down, hydrological exchange and bioturbation in the hyporheic zone can destroy the clogging layer, causing the declogging process and increasing in hydraulic conductivity. The current studies are limited to the analysis of the variations of measured streambed hydraulic conductivity data, and the mechanism of the clogging and declogging processes in the hyporheic zone of a river requires more investigations.
2013(3):127-131.
Abstract:
Road slope instability is likely to cause significant losses of human life, property, and economic activities; therefore the slope safety risk assessment is an important task in the engineering construction. In this paper, the slope at the outlet of Yangnangou tunnel on the road between Shiyan and Baihe of Hubei Province was investigated using the, Monte Carlo simulation to obtain its stability coefficient and probability to failure under the conditions of normal and abnormal conditions. Additionally, the vulnerability for the hazard-affected body within the impacted area was analyzed, which can provide the possible economic losses and population casualties through the risk calculation formula. The results showed that the level of risk of the slope at the Yangnangou tunnel exit under the normal working conditions is class I, while the level of risk under the abnormal working conditions is class II . According to the risk acceptance criteria, this slope had less risk under the normal working conditions and the risk was within the acceptable range. This slope had higher risk under the abnormal working conditions; therefore the deformation of the slope needs to be monitored, especially under the construction process and adverse natural conditions.
Road slope instability is likely to cause significant losses of human life, property, and economic activities; therefore the slope safety risk assessment is an important task in the engineering construction. In this paper, the slope at the outlet of Yangnangou tunnel on the road between Shiyan and Baihe of Hubei Province was investigated using the, Monte Carlo simulation to obtain its stability coefficient and probability to failure under the conditions of normal and abnormal conditions. Additionally, the vulnerability for the hazard-affected body within the impacted area was analyzed, which can provide the possible economic losses and population casualties through the risk calculation formula. The results showed that the level of risk of the slope at the Yangnangou tunnel exit under the normal working conditions is class I, while the level of risk under the abnormal working conditions is class II . According to the risk acceptance criteria, this slope had less risk under the normal working conditions and the risk was within the acceptable range. This slope had higher risk under the abnormal working conditions; therefore the deformation of the slope needs to be monitored, especially under the construction process and adverse natural conditions.
2013(3):132-137.
Abstract:
A multi-layer groundwater level-water quality monitoring system has been developed to investigate the aquifer-aquitard system that is located from the bottom of 1st aquifer to the top of 2nd aquifer, across the saltwater-freshwater transitional zone in the North China Plain. Based upon those boreholes, a series of in-situ tests have been carried out such as the pumping test, slug test, as well as tracer test in different layers. The hydrogeogical parameters in the aquifer-aquitard system have been obtained using the analytical method and numerical simulation method. The results show that the hydraulic conductivity and the storage coefficient at the bottom layer of 1st aquifer are 4.320～7.550 m/d and 4.53×10-4～2.19×10-3, respectively; the hydraulic conductivity, the longitudinal dispersion, and the longitudinal dispersivity in the aquitard are 2.20×10-3～7.65×10-3 m/d, 0.023～0.428 m2/d, and 0.010～0.051 m, respectively; and the hydraulic conductivity and the storage coefficient at the top layer of 2nd aquifer are 0.142～0.929 m/d and 4.53×10-4～2.19×10-3, respectively.
A multi-layer groundwater level-water quality monitoring system has been developed to investigate the aquifer-aquitard system that is located from the bottom of 1st aquifer to the top of 2nd aquifer, across the saltwater-freshwater transitional zone in the North China Plain. Based upon those boreholes, a series of in-situ tests have been carried out such as the pumping test, slug test, as well as tracer test in different layers. The hydrogeogical parameters in the aquifer-aquitard system have been obtained using the analytical method and numerical simulation method. The results show that the hydraulic conductivity and the storage coefficient at the bottom layer of 1st aquifer are 4.320～7.550 m/d and 4.53×10-4～2.19×10-3, respectively; the hydraulic conductivity, the longitudinal dispersion, and the longitudinal dispersivity in the aquitard are 2.20×10-3～7.65×10-3 m/d, 0.023～0.428 m2/d, and 0.010～0.051 m, respectively; and the hydraulic conductivity and the storage coefficient at the top layer of 2nd aquifer are 0.142～0.929 m/d and 4.53×10-4～2.19×10-3, respectively.
2013(3):138-141.
Abstract:
The Zhanggu Landslide lies at the right bank of the Daduhe River and 2.5 km downstream of Guza Town, which is a super large-scale landslide with a volume of 19000×104 m3. This area belongs to the highly seismic region. Once the landslide is damaged, it can result in river blocking and dam break. In order to analyze the evolution process and develop trend of the landslide, the field investigation, geological mapping, geophysical prospecting, and laboratory dating methods were used to investigate the formation-evolution mechanism and stability of the Zhanggu Landslide based on the numerical simulation using the three-dimensional finite element software (FLAC-3D). The results showed that the Zhanggu Landslide is a palaeo-earthquakr landslide and its formation includes four stages: unloading and relaxation of the Daduhe River, lateral erosion of the Daduhe River, slope failure triggered by a strong earthquake, and river dam erosion. At present, the landslide is in stable condition but a secondary landslide may occur on the local scale.
The Zhanggu Landslide lies at the right bank of the Daduhe River and 2.5 km downstream of Guza Town, which is a super large-scale landslide with a volume of 19000×104 m3. This area belongs to the highly seismic region. Once the landslide is damaged, it can result in river blocking and dam break. In order to analyze the evolution process and develop trend of the landslide, the field investigation, geological mapping, geophysical prospecting, and laboratory dating methods were used to investigate the formation-evolution mechanism and stability of the Zhanggu Landslide based on the numerical simulation using the three-dimensional finite element software (FLAC-3D). The results showed that the Zhanggu Landslide is a palaeo-earthquakr landslide and its formation includes four stages: unloading and relaxation of the Daduhe River, lateral erosion of the Daduhe River, slope failure triggered by a strong earthquake, and river dam erosion. At present, the landslide is in stable condition but a secondary landslide may occur on the local scale.
2013(3):142-146.
Abstract:
The descriptive analysis, correlation analysis, and principal component analysis were used to investigate the distribution characteristics and formation function of groundwater chemical components in the Guanzhong Basin based on 162 groundwater samples. The results showed that the dominant cation is HCO3- of the shallow groundwater in the study area, and the dominant anion is Ca2+ in the south of Wei River, and Na+ in the north of Wei River. The concentrations of HCO3-, Ca2+, and Mg2+ were stable while the concentrations of Cl- and SO42- varied significantly and were sensitive to the environmental factors. The formation functions of hydrochemical field were different between the north and south of Wei River with the weathering and leaching functions in the south of Wei River and the mineral dissolution and evaporation concentration functions in the north of Wei River. The results in this study can provide scientific references for the sustainable utilization of water resources and environmental management in this area.
The descriptive analysis, correlation analysis, and principal component analysis were used to investigate the distribution characteristics and formation function of groundwater chemical components in the Guanzhong Basin based on 162 groundwater samples. The results showed that the dominant cation is HCO3- of the shallow groundwater in the study area, and the dominant anion is Ca2+ in the south of Wei River, and Na+ in the north of Wei River. The concentrations of HCO3-, Ca2+, and Mg2+ were stable while the concentrations of Cl- and SO42- varied significantly and were sensitive to the environmental factors. The formation functions of hydrochemical field were different between the north and south of Wei River with the weathering and leaching functions in the south of Wei River and the mineral dissolution and evaporation concentration functions in the north of Wei River. The results in this study can provide scientific references for the sustainable utilization of water resources and environmental management in this area.
31 Seepage Characteristics and Stability Evaluation of Landslide Cover Considering Rain Infiltration
2013(3):147-150.
Abstract:
Rain infiltration is an important factor on the stability of slope in the reservoir area. In order to analyze the effects of rain infiltration on the Shangtianzhen landslide body in the upstream reservoir area of Kala hydropower station in the Yalong River Basin, a two-dimensional unsaturated and saturated seepage field model was developed based on a typical profile of the Shangtianzhen landslide body. The finite element method was used to simulate the rain infiltration process. The simulation results were used to analyze the seepage characteristics and stress distribution of the landslide body under heavy rain infiltration before and after impounding, and to evaluate the stability and effect of protective measures of the slope. The results indicated that rain infiltration can reduce the slope stability and may even cause slope instability.
Rain infiltration is an important factor on the stability of slope in the reservoir area. In order to analyze the effects of rain infiltration on the Shangtianzhen landslide body in the upstream reservoir area of Kala hydropower station in the Yalong River Basin, a two-dimensional unsaturated and saturated seepage field model was developed based on a typical profile of the Shangtianzhen landslide body. The finite element method was used to simulate the rain infiltration process. The simulation results were used to analyze the seepage characteristics and stress distribution of the landslide body under heavy rain infiltration before and after impounding, and to evaluate the stability and effect of protective measures of the slope. The results indicated that rain infiltration can reduce the slope stability and may even cause slope instability.
2013(3):151-154.
Abstract:
In order to identify whether the groundwater quality in Nanning is suitable for the development and utilization of water source heat pump，the water quality suitability evaluation indexes were selected which were related to the design and operation of the water source heat pump system based on the hydrochemical analysis of groundwater samples collected from the unconfined aquifer of Nanning city. The hierarchical structure model was developed using the Analytic Hierarchy Process (AHP) to determine the weights for each evaluation index, and the spatial analysis module of the GIS platform was used to obtain the water quality evaluation zonation of groundwater source. The results showed that the suitable area to develop water source heat pump is 280.7 km2 located mainly in the central part of Nanning city and Liangqing District. Due to that groundwater in these areas is almost neutral water with little hardness and has no harm to the pipelines and facilities, it is suitable for the development of groundwater source heat pump.
In order to identify whether the groundwater quality in Nanning is suitable for the development and utilization of water source heat pump，the water quality suitability evaluation indexes were selected which were related to the design and operation of the water source heat pump system based on the hydrochemical analysis of groundwater samples collected from the unconfined aquifer of Nanning city. The hierarchical structure model was developed using the Analytic Hierarchy Process (AHP) to determine the weights for each evaluation index, and the spatial analysis module of the GIS platform was used to obtain the water quality evaluation zonation of groundwater source. The results showed that the suitable area to develop water source heat pump is 280.7 km2 located mainly in the central part of Nanning city and Liangqing District. Due to that groundwater in these areas is almost neutral water with little hardness and has no harm to the pipelines and facilities, it is suitable for the development of groundwater source heat pump.
2013(3):155-159.
Abstract:
Based on GIS secondary development and the project data organization and analysis, a system internal database was designed and built, which was used further and combined with the control and component technology to develop the environmental and geological survey information system in the Huaihe River Basin (HHEGData system). The developed system internal database (HWData) of the HHEGData system includes all the data, maps, and documents obtained from the project survey and testing. The design of HHEGData system includes two main function modules - attribute database management module and spatial database management module, which can provide more standard and more convenient data inquires based on project data type, and realize the dual visualization and various inquires of the attribute data and spatial data. The information system can offer technical and information support for the measures of protection and sustainable development and utilization of groundwater resources .
Based on GIS secondary development and the project data organization and analysis, a system internal database was designed and built, which was used further and combined with the control and component technology to develop the environmental and geological survey information system in the Huaihe River Basin (HHEGData system). The developed system internal database (HWData) of the HHEGData system includes all the data, maps, and documents obtained from the project survey and testing. The design of HHEGData system includes two main function modules - attribute database management module and spatial database management module, which can provide more standard and more convenient data inquires based on project data type, and realize the dual visualization and various inquires of the attribute data and spatial data. The information system can offer technical and information support for the measures of protection and sustainable development and utilization of groundwater resources .
2013(3):160-164.
Abstract:
In order to investigate the effects of different ground film forms on the deep percolation of cultivating vegetable in greenhouse, celery was chosen as the experimental sample, and four experimental groups with different ground film forms in the horizontal strip and U-shaped strip with different interval widths were designed in the study area and another group without ground film was also conducted for comparison. The variation process of soil moisture was measured by the PR1 layered moisture probe combining with the oven drying method. The time for irrigation was determined based on the observation data of soil moisture in the root layer. The automatic meteorological station was set up in the greenhouse to collect the meteorological data. The evapotranspiration of celery during the growth period was calculated using the energy balance method. The deep percolation for each type of ground film was calculated using the water balance equation, which can be used to determine the impacts of different ground film forms on the deep percolation. The results showed that under all types of ground film, the celery grows well and the deep percolation is reduced to some extent. The ground film in the U-shaped strip has better effects on reducing deep percolation that that in the horizontal strip and the effect of reducing deep percolation is better for the same ground film form with smaller interval widths. After the ground film, the time interval between irrigations increases, the total amount of irrigation and the frequency of irrigation reduce for most cases, and the deep percolation reduces by 50% under the ideal situation. Consequently, the deep percolation can be reduced and irrigation water can be saved using the ground film when cultivating vegetable in greenhouse, but the optimal configuration parameters under various conditions need further experimental or numerical analysis.
In order to investigate the effects of different ground film forms on the deep percolation of cultivating vegetable in greenhouse, celery was chosen as the experimental sample, and four experimental groups with different ground film forms in the horizontal strip and U-shaped strip with different interval widths were designed in the study area and another group without ground film was also conducted for comparison. The variation process of soil moisture was measured by the PR1 layered moisture probe combining with the oven drying method. The time for irrigation was determined based on the observation data of soil moisture in the root layer. The automatic meteorological station was set up in the greenhouse to collect the meteorological data. The evapotranspiration of celery during the growth period was calculated using the energy balance method. The deep percolation for each type of ground film was calculated using the water balance equation, which can be used to determine the impacts of different ground film forms on the deep percolation. The results showed that under all types of ground film, the celery grows well and the deep percolation is reduced to some extent. The ground film in the U-shaped strip has better effects on reducing deep percolation that that in the horizontal strip and the effect of reducing deep percolation is better for the same ground film form with smaller interval widths. After the ground film, the time interval between irrigations increases, the total amount of irrigation and the frequency of irrigation reduce for most cases, and the deep percolation reduces by 50% under the ideal situation. Consequently, the deep percolation can be reduced and irrigation water can be saved using the ground film when cultivating vegetable in greenhouse, but the optimal configuration parameters under various conditions need further experimental or numerical analysis.
2013(3):165-168.
Abstract:
Six types of anti-seepage canal lining forms were selected from the aspects of impervious material, anti-frost heaving, and dilatation joint in the Shijin Irrigation District. Dynamic water method was used to conduct the field tests on the effects of canal anti-seepage, and a calculation formula was proposed to characterize the water loss in canal conveyance. Through the comparisons of the anti-seepage effects, anti-frost heaving effects, water saving effects, and investment benefits of the six lining forms before and after the thaw period, the water loss rate per unit length for the lining form of “cast-in-place concrete plus heated board with resinous balm and mortar” was 0.0306 /km, the investment per unit length was 53.73 million Yuan/km, and the anti-seepage effects kept unchanged before and after the thaw period. In summary, this canal lining form was suitable in the Shijin Irrigation District and may be applied to other anti-seepage engineering projects in North China.
Six types of anti-seepage canal lining forms were selected from the aspects of impervious material, anti-frost heaving, and dilatation joint in the Shijin Irrigation District. Dynamic water method was used to conduct the field tests on the effects of canal anti-seepage, and a calculation formula was proposed to characterize the water loss in canal conveyance. Through the comparisons of the anti-seepage effects, anti-frost heaving effects, water saving effects, and investment benefits of the six lining forms before and after the thaw period, the water loss rate per unit length for the lining form of “cast-in-place concrete plus heated board with resinous balm and mortar” was 0.0306 /km, the investment per unit length was 53.73 million Yuan/km, and the anti-seepage effects kept unchanged before and after the thaw period. In summary, this canal lining form was suitable in the Shijin Irrigation District and may be applied to other anti-seepage engineering projects in North China.
2013(3):169-172.
Abstract:
More than 5500 pumping stations have been constructed in China until 2004; however, the constructed pumping stations have some shortcomings such that the type of main motors and the mode of transmission are quite unitary. In recent years, new type of motors and new mode of transmissions appear and they have been successfully applied in other industries. Consequently, it is necessary to investigate the feasibility of new type of motors and new mode of transmissions applied in pumping stations. In this paper, the application examples of high speed motor supporting reduction gear transmission mode are introduced, the effects of the above mode and direct transmission mode on the total weight of unit are compared, and the application prospect and feasibility of AC-excited motors and inner-feedback motors in the large- and medium-sized pumping stations are discussed. The AC-excited motor has been successfully applied in wind power, whereas the inner-feedback motor has been successfully applied in power plants and waterworks... Finally, this paper proposes that application of the new type of motors and new mode of transmissions should be promoted in the construction and transformation of large- and medium-sized pumping stations, which can achieve the purposes of investment saving, energy conservation, and improvement of pumping station technology.
More than 5500 pumping stations have been constructed in China until 2004; however, the constructed pumping stations have some shortcomings such that the type of main motors and the mode of transmission are quite unitary. In recent years, new type of motors and new mode of transmissions appear and they have been successfully applied in other industries. Consequently, it is necessary to investigate the feasibility of new type of motors and new mode of transmissions applied in pumping stations. In this paper, the application examples of high speed motor supporting reduction gear transmission mode are introduced, the effects of the above mode and direct transmission mode on the total weight of unit are compared, and the application prospect and feasibility of AC-excited motors and inner-feedback motors in the large- and medium-sized pumping stations are discussed. The AC-excited motor has been successfully applied in wind power, whereas the inner-feedback motor has been successfully applied in power plants and waterworks... Finally, this paper proposes that application of the new type of motors and new mode of transmissions should be promoted in the construction and transformation of large- and medium-sized pumping stations, which can achieve the purposes of investment saving, energy conservation, and improvement of pumping station technology.
2013(3):173-176.
Abstract:
According to the engineering characteristics of the pump station, the closed circulating water supply system composed of the coiled pipe cooling device which was installed in natural water for cooling is an energy-saving and reliable technical water supply mode. The heat transfer principle of the coiled pipe cooler was analyzed using the heat transfer theory, and the calculation formulas of heat exchange area of coiled pipe cooler under different installation forms were proposed. The results showed that (1) when the coiled pipe cooler is in static water with natural convection heat transfer and water capacity is used to carry away heat, the heat exchange area of the coiled pipe cooler is the largest; (2) when the coiled pipe cooler is in flowing water with forced convection heat transfer and water flow is used to carry away heat, the heat exchange area of the coiled pipe cooler is the lower; (3) increasing of the pipe internal thermal fluid or the flow rate of cooling water outside of the pipe can reduce the heat transfer area, but it increases the pipeline installation requirements and operation cost; and (4) the stainless steel material is recommended for the coil material in order to save the investment and prolong the service life.
According to the engineering characteristics of the pump station, the closed circulating water supply system composed of the coiled pipe cooling device which was installed in natural water for cooling is an energy-saving and reliable technical water supply mode. The heat transfer principle of the coiled pipe cooler was analyzed using the heat transfer theory, and the calculation formulas of heat exchange area of coiled pipe cooler under different installation forms were proposed. The results showed that (1) when the coiled pipe cooler is in static water with natural convection heat transfer and water capacity is used to carry away heat, the heat exchange area of the coiled pipe cooler is the largest; (2) when the coiled pipe cooler is in flowing water with forced convection heat transfer and water flow is used to carry away heat, the heat exchange area of the coiled pipe cooler is the lower; (3) increasing of the pipe internal thermal fluid or the flow rate of cooling water outside of the pipe can reduce the heat transfer area, but it increases the pipeline installation requirements and operation cost; and (4) the stainless steel material is recommended for the coil material in order to save the investment and prolong the service life.
2013(3):177-179.
Abstract:
Based on the wave ray propagation theory in the homogeneous medium, a velocity model was developed for the forward calculation of ray using the straight ray tracking method. The model was simulated inversely using the SIRT and LSQR algorithms. The results showed that LSQR algorithm can achieve a better balance in the accuracy, efficiency, and stability. The seismic tomography method was applied to the adit exploration on the right bank of a hydropower station in the karst development area. This method can determine the velocity distribution of the rock mass and the spatial distribution of K25 cave in the area. Compared with the results obtained from other methods, it suggested that the seismic tomography method has the advantages of high resolution, intuitive image, and easy to explain when used for the karst development area.
Based on the wave ray propagation theory in the homogeneous medium, a velocity model was developed for the forward calculation of ray using the straight ray tracking method. The model was simulated inversely using the SIRT and LSQR algorithms. The results showed that LSQR algorithm can achieve a better balance in the accuracy, efficiency, and stability. The seismic tomography method was applied to the adit exploration on the right bank of a hydropower station in the karst development area. This method can determine the velocity distribution of the rock mass and the spatial distribution of K25 cave in the area. Compared with the results obtained from other methods, it suggested that the seismic tomography method has the advantages of high resolution, intuitive image, and easy to explain when used for the karst development area.
2013(3):180-184.
Abstract:
The effects of typhoon on the dam include the effects of heavy rainfall and reservoir water level fluctuation caused by typhoon, and the typhoon wind load on the dam .According to the loading and unloading response ratio theory, the criteria of enhanced and sustaining dam effects under the action of typhoon were investigated. The calculation methods of water level loading and unloading response ratio (LURR) and wave LURR were proposed, which provided the evaluation criteria of enhanced and sustaining dam effects under the action of typhoon. The presented method and evaluation criteria were used to analyze the Number 10 typhoon “Moranti” on the Dongwu reservoir dam in 2010. The results showed that the typhoon has insignificant effects on the Dongwu reservoir dam and the dam is in stable. The introduction of LURR into the hydraulic engineering field can expand the application scope of the LURR theory and is also the new idea to study the dam stability under the action of typhoon.
The effects of typhoon on the dam include the effects of heavy rainfall and reservoir water level fluctuation caused by typhoon, and the typhoon wind load on the dam .According to the loading and unloading response ratio theory, the criteria of enhanced and sustaining dam effects under the action of typhoon were investigated. The calculation methods of water level loading and unloading response ratio (LURR) and wave LURR were proposed, which provided the evaluation criteria of enhanced and sustaining dam effects under the action of typhoon. The presented method and evaluation criteria were used to analyze the Number 10 typhoon “Moranti” on the Dongwu reservoir dam in 2010. The results showed that the typhoon has insignificant effects on the Dongwu reservoir dam and the dam is in stable. The introduction of LURR into the hydraulic engineering field can expand the application scope of the LURR theory and is also the new idea to study the dam stability under the action of typhoon.
2013(3):185-188.
Abstract:
Claim events always happen during the implementation process of large hydraulic and hydroelectric engineering. Compared with the contractor with rich claiming experiences, the claiming management level of the owner falls behind. The game theory has a unique advantage in the discussion of how the owner of the large hydraulic and hydroelectric engineering performs the claiming management. Due to that the owner and contractor have obtained the asymmetric claiming information, the asymmetric information dynamic game model of the claiming management of the owner is developed to investigate the optimal solution of the behavior options under two strategies with and without claiming management by the owner when claiming fraud exists. The results indicate that the overall standard of the industry and claiming rate can affect the decision made by the owner of whether to make claiming management. On the other hand, the strategy selection of the owner can restrict the fraud claiming of the contractor. Moreover, a reasonable value of the fraud claiming fine “f” can reduce the occurrence of the fraud claiming.
Claim events always happen during the implementation process of large hydraulic and hydroelectric engineering. Compared with the contractor with rich claiming experiences, the claiming management level of the owner falls behind. The game theory has a unique advantage in the discussion of how the owner of the large hydraulic and hydroelectric engineering performs the claiming management. Due to that the owner and contractor have obtained the asymmetric claiming information, the asymmetric information dynamic game model of the claiming management of the owner is developed to investigate the optimal solution of the behavior options under two strategies with and without claiming management by the owner when claiming fraud exists. The results indicate that the overall standard of the industry and claiming rate can affect the decision made by the owner of whether to make claiming management. On the other hand, the strategy selection of the owner can restrict the fraud claiming of the contractor. Moreover, a reasonable value of the fraud claiming fine “f” can reduce the occurrence of the fraud claiming.
2013(3):189-192.
Abstract:
The reliability evaluation model of the sluice system of the Llower Yellow River was establishedwas used to assess the evaluation indexes affecting the sluice reliability from three aspects of safety, applicability, and durability, and it provided the based on provision of scoring criteria and values standards of the relevant indexes. The classification of final judging category categories of this model was in line with the provisions of evaluation standard of the the sluice security category of evaluation standard provisions in sluice safety appraisal. In this paper, the rReliability eEvaluation model of sSluice sSystem of the Llower Yellow River was applied to analyze the reliability of the sluice for diverting water from the lower Yellow River at Zhaok Kou, based on the in-situ safety testing and calculation recheck. The results wereis consistent with the safety appraisal conclusions of the safety appraisal the sluice; therefore this model, so it can be provided the technical support for the maintenance, strengthening, reconstruction, and redevelopmentconstruction of the sluices’ projects.
The reliability evaluation model of the sluice system of the Llower Yellow River was establishedwas used to assess the evaluation indexes affecting the sluice reliability from three aspects of safety, applicability, and durability, and it provided the based on provision of scoring criteria and values standards of the relevant indexes. The classification of final judging category categories of this model was in line with the provisions of evaluation standard of the the sluice security category of evaluation standard provisions in sluice safety appraisal. In this paper, the rReliability eEvaluation model of sSluice sSystem of the Llower Yellow River was applied to analyze the reliability of the sluice for diverting water from the lower Yellow River at Zhaok Kou, based on the in-situ safety testing and calculation recheck. The results wereis consistent with the safety appraisal conclusions of the safety appraisal the sluice; therefore this model, so it can be provided the technical support for the maintenance, strengthening, reconstruction, and redevelopmentconstruction of the sluices’ projects.
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