软土地基上桥台后填土工后沉降的数值分析

在分析软土地基上桥后填土受力特性的基础上提出有限元简化计算模型,并采用可模拟超填的Biot固结有限元程序就桥后填筑EPS、粉煤灰、粉细砂和砂砾情况下路堤填土工后沉降问题进行数值分析研究。计算结果表明:采用轻质回填材料(如EPS和粉煤灰)可有效减少路桥过渡处差异沉降;同时还可降低桥台前后区域因软土塑性剪切区贯通而发生滑动失稳破坏的可能。此外,填料的强度对于路堤自身的压缩变形起控制作用,因此采用轻质填料的同时不应降低填料的变形模量。

Numerical Analysis of Post-construction Settlements of Backfills Adjacent to Abutment on Soft Clay Foundations

A simplified FE model has been proposed after investigation of the mechanical conditions of the backfills adjacent to abutment,and numerical simulations on post-construction settlement of the backfills such as gravel sand fly ash and EPS are carried out by the FE program in which Biot's consolidation and additional filling can be taken into account.The results indicate that the differential settlement between abutment and embankment can be greatly reduced by using lightweight backfills and slippage failure due to transfixion of the plastically deforming areas in soft clay can be prevented.Since the strength characteristics of the backfills have a significant effect on the compressive deformation,the sufficient deformation modulus must be held when the lightweight backfills are used.