循环大中主应力耦合作用下饱和软粘土的动力特性

Study on the Dynamic Characteristics of Saturated Soft Clay with Coupling Effect of Main Stress in Circulation

为更加真实地模拟交通荷载引起的复杂动应力场,基于GDS动静真三轴测试系统,通过循环大主应力及循环中主应力的耦合,模拟交通荷载下竖向及水平向循环正应力的耦合,探讨循环中主应力系数、循环大主应力幅值等对饱和软粘土累积变形特性的影响,建立能考虑循环中主应力影响的饱和软粘土累积应变预测模型。试验结果表明,一方面,循环中主应力大大加快了永久中主应变的发展速度;另一方面,随着循环中主应力系数的增大,永久大主应变的累积速度逐渐减小,表明循环中主应力的存在大大降低了路基在交通荷载下的沉降。

In order to better imitate the complex dynamic stress field resulting from traffic load, efforts have been made to imitate the vertical and horizontal normal stress coupling in circulation under traffic load. This study is based on triaxial GDS static and dynamic testing system. It is designed to explore the effect of main stress coefficient in circulation and main stress amplitude in circulation on the characteristics of accumulated deformation of saturated clay. And it is expected to create a model to predict the effect of main stress in circulation on the accumulated deformation of saturated clay. The test results reveal that on one hand, the main stress in circulation greatly speeds up the development of permanent principal strain; and on the other hand, with the increasing of main stress coefficient in circulation, the permanent principal strain slows down in accumulating, which shows that main stress in circulation greatly prevents roadbed from sinking under traffic load.