软黏土蠕变试验及其经验模型研究

针对湖南竹城公路路基软土开展了系统的三轴固结不排水蠕变试验，得到不同围压、不同应力加载等级下的全过程蠕变曲线。进而通过“陈氏加载法”得到分别加载下蠕变曲线和应力-应变等时曲线。以围压100 kPa为例，得出应力-应变关系采用幂函数，而应变-时间关系采用双曲线关系的蠕变方程。对比分析表明，该蠕变方程较Singh-Mitchell模型、Mesri模型更适应试验数据，能够更好地反映和预测该软土的蠕变特性。

Creep tests on soft clay and its empirical models

Based on the stress-control triaxial apparatus, the CU triaxial creep tests of subgrade soft clay under different confining pressures were carried out by using multi-grade loading mode. The full-process creep curves under different confining pressures were obtained. Furthermore, the creep curves of multi-step constant load，the equal-time stress-strain curves were gained by using “Chen method”. Taking the confining pressure 100 kPa for example, a power&;hyperbolic creep equation was proposed. In the equation, the power and hyperbolic equation are to model stress-strain and strain-time relationship respectively. Compared with Singh-Mitchell’s model and Mesri’ model, the creep equation suggested is thought to be more suitable to reflect the creep characteristics.