[关键词]
[摘要]
加筋土结构中的筋材,在长期稳定拉伸力的作用下,会发生蠕变变形,变形将会随着时间的增大而不断增大,如果蠕变变形超过允许值,就会引起加筋土结构的破坏。在冬季,北方寒冷地区的土壤温度长时间处于0 ℃~-20 ℃,在这样的温度下使用格栅,就必须考虑低温对格栅蠕变性能的影响。-20 ℃、-10 ℃、0 ℃和20 ℃等不同温度下玻纤格栅的蠕变试验表明:玻纤格栅在负温时的蠕变量明显小于其在常温下的蠕变量;相同温度下,荷载水平越高其达到稳定时的蠕变量也越大;相同荷载水平下,温度越低其达到稳定时的蠕变量也越小;负温时的蠕变变形随荷载增加的速率要明显低于常温20 ℃的情况,同时基本上符合温度越低,速率增长越慢的规律。
[Key word]
[Abstract]
The reinforced material in the reinforced soil can show creep deformation under the long-term stable drawing force and the deformation increases with time. If the creep deformation oversteps the allowable value, then the reinforced soil structure would be damaged. In the cold regions of northern China, soil temperature is between 0℃and -20℃ in winter. Application of glass fiber grid under this condition needs to take into account the effects of low temperature on the creep characteristics of glass fiber grid. The creep tests of glass fiber grid were performed under different temperature of -20℃, -10℃, 0℃, and 20℃. The results showed that (1) the creep deformation of glass fiber grid under negative temperatures was lower than that under normal temperature; (2) under the same temperature, the creep deformation increased with the increasing of loading level; (3) under the same loading lever, the creep deformation decreased with the decreasing of temperature; and (4) the increasing rate of creep deformation with loading level under negative temperatures was lower than that under normal temperature (20℃), which was in accordance with the rule of that lower increasing rate of creep deformation accompanies with lower temperature.
[中图分类号]
[基金项目]