宕渣土桥背回填冲击累积变形研究

Research on accumulated deformation due to the impact on bridge back backfilled with earthworks mixtures

为了研究宕渣土作为桥背回填材料的冲击累积变形,文章通过现场冲击累积变形试验,对试验结果进行ABAQUS有限元仿真模拟,分析其回弹模量和内摩擦角,用所得的参数建立动态黏弹性模型,得到桥背回填宕渣土在冲击荷载下的力学响应和累积变形特征。研究表明:宕渣土适宜作为桥背回填材料,且随着冲击次数的不断增加,桥背回填处宕渣土路基的回弹模量呈线性增长,而累积沉降呈幂函数形式增长,但增长速率逐渐变缓,最终达到稳定。

In order to study the accumulated deformation brought about by the impact on the bridge back backfilled with earthworks mixtures, the site impact accumulated deformation tests were carried out, and the test results were simulated by the finite element software ABAQUS. The mechanical re-sponse and accumulated deformation characteristics were obtained through the analysis of rebound modulus and internal friction angles, and the parameters were used to construct the dynamic viscoelas-tic model. It is concluded that the earthworks mixtures are appropriate to be backfilling materials. Be-sides, as the number of the impact increases, the rebound modulus of the bridge back roadbed back- filled with earthworks mixtures increases in a linear way, and the accumulated settlement grows in a way of power function, but its rate of growth slows down gradually into a stable level.