重复荷载作用下路基土粘弹塑性永久变形预估

Visco-elastic-plastic model of permanent deformation of subgrade soils under repeated load

为准确描述重复荷载作用下路基土3阶段永久变形特性,在五元件粘弹塑性体蠕变方程的基础上,通过把正弦荷载转化为恒定荷载,推导出重复荷载作用下路基土永久变形理论预估模型;进行了路基土重复加载动三轴试验,获得了路基土永久变形发展曲线,并采用理论模型对试验曲线进行了回归。结果表明:在重复荷载作用下,路基土永久变形发展明显呈现3个阶段;理论模型可以较准确地描述路基土3阶段永久变形特性。

In order to describe the permanent deformation characteristics with three stages of sub grade soil under repeated load test, based on the creep equations of visco-elastic-plastic model with five components, after translating the pulse load consisting of a haversine loading and a rest period into a constant load, a theoretical prediction model for the permanent deformation under repeated load was deduced. The repeated load dynamic triaxial tests were carried out to obtain the permanent deformation curves. The test results were regressed by the theoretical model. The resuits show that the permanent deformation with three stages of subgrade soils will happen under repeated load dynamic triaxial tests, the theoretical model can predict the permanent deformation with three stages very well. 1 tab, 4 figs, 12 refs.