Cohesive relationship of design storm return period of two-stage urban drainage system in Shenzhen City
- Article
- Figures
- Metrics
- Preview PDF
- Reference
- Related
- Cited by
- Materials
Abstract:
Urban water logging problem becomes more and more prominent under the changing environment. Municipal drainage and river drainage are important systems related to urban water security, and they jointly determine the safety of urban flood control and waterlogging. However, due to several factors such as sample selection method, design storm return period, design rain pattern, and design flow method, it is difficult to connect the urban two-stage drainage system in the design.Hourly rainfall data was selected by the annual maximum method and the annual multiple sample method to construct rainfall structure relationships with predominantly short duration and predominantly long duration. Aiming at the current urban two-stage drainage system standards that can not be connected effectively, the two types of cohesive risks that a two-stage drainage system may encounter were considered in the Grand Airport District of Shenzhen City. The cohesive relation of design storm return period based on municipal short duration and water conservancy long duration were investigated respectively. At the same time, combined with the Chicago rain pattern and the Pearl River Delta rain pattern, the design storm processes of the two-stage drainage system were deduced respectively, and the cohesive relationship between the design of storm peak of urban two-stage drainage system was discussed. The Spearman rank correlation coefficient was used to evaluate the correlation between the connection relationship of each tributary in the Intercepting River basin and the river length, slope, catchment area, and other parameters.In the rainfall structure relationship based on short duration, it was found that the standard articulation of the urban two-stage drainage system showed an increasing trend with increasing rainfall duration, and did not show significant changes with increasing municipal storm return period (0.33~10 a). The articulation of the urban two-stage drainage system is an articulation relationship under the combined effect of the rainfall duration and rainfall intensity. In the rainfall structure relationship dominated by long duration, it was detected that the municipal drainage system was more likely to experience long-duration, small-intensity storms when the water conservancy drainage system was subjected to small return period storms. The municipal drainage system was more likely to experience short-duration, large-intensity storms when the water conservancy drainage system was subjected to large return period storms. The design of stormwater peak articulation of the urban two-stage drainage system revealed that the articulation relationships varied among the tributaries in the Interceptor River basin. Thus, the Spearman rank correlation coefficient analysis revealed a strong correlation between the design stormwater peak articulation relationship and the geographic parameters. Among them, the Spearman correlation coefficients of the articulation relationship with the calculation period, catchment area characteristic parameters, and lag time are 0.82, 0.87, and 0.68 respectively. The results of the above characterizations indicate that the articulation relationship between the return period of water conservancy drainage and municipal drainage is affected by the rainfall intensity and rainfall duration, and also presents a regional heterogeneity. For instance, there are about 2 to 3 times between urban two-stage drainage systems in Tak Fung Wai Chung. That is, when the return period of municipal drainage design is once in X years, the return period of water conservancy drainage design should be designed at least (2 to 3) X years to achieve the connection of an urban two-stage drainage system. Therefore, it is possible to classify the areas in advance and study the relationship between the two-stage drainage system standards by zoning, to obtain a more generalized conclusion.
Keywords:
Project Supported:
Clc Number:
Mobile website
® 2024 All Rights Reserved
冀公网安备13010502002656号
冀公网安备13010502002656号