论文部分内容阅读
在交通荷载作用下,地基土单元不仅偏应力大小周期性变化而且主应力轴连续旋转。为了研究交通荷载应力路径下地基土单元排水变形特性,利用动态空心圆柱仪对K0固结下饱和砂土进行了一系列“苹果型”动力循环应力路径以及普通动力循环应力路径试验。两组应力路径试验结果的对比表明交通荷载应力路径引起的主应力轴连续旋转会加速竖向永久变形的累积,并且对竖向回弹模量具有软化作用,而且随着循环应力比的增大,两种应力路径下变形特性差异变得更加明显。最后,基于Uzan回弹模量模型提出了相应的修正公式用来考虑主应力轴旋转效应。
Under the action of traffic load, the subsoil units not only periodically change the magnitude of deviatoric stress but also continuously rotate the principal stress axis. In order to study the deformation characteristics of foundation soil unit under traffic load stress path, a series of “apple type” power cycle stress paths and ordinary power cycle stress path tests of saturated sand under K0 consolidation were carried out by dynamic hollow cylinder. Comparison of the stress path test results shows that the continuous rotation of the main stress axis caused by the traffic stress path accelerates the accumulation of vertical permanent deformation and softens the vertical modulus of elasticity. With the increase of cyclic stress ratio , The difference between the deformation characteristics of the two stress paths becomes more obvious. Finally, a corresponding correction formula is proposed based on the Uzan modulus of elasticity model to consider the principal stress axis rotation effect.