软土地基高速公路路基拓宽改建全过程变形特性数值模拟  

Numerical simulation on deformation behaviors for widened expressway embankment over soft ground

作　　者：蒋鑫[1,2,3] 蒋怡[1,2,3] 梁雪娇[1,2,3] 吴朝阳[1,2,3] 邱延峻[1,2,3] 

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]西南交通大学道路工程四川省重点实验室,四川成都610031 [3]西南交通大学高速铁路线路工程教育部重点实验室,四川成都610031

出　　处：《铁道科学与工程学报》2015年第5期1039-1046,共8页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(51378440);国家重点基础研究发展计划(973计划)项目(2013CB036204);中央高校基本科研业务费专项资金资助项目(SWJTU12CX067)

摘　　要：为研究软土地基高速公路路基拓宽改建全过程的变形特性,基于有限元数值模拟,对比分析一次性新建而成的窄路基、宽路基及拓宽改建而成的宽路基地基表面沉降、路基表面沉降及地基侧向变形等演变规律。研究结果表明:拓宽改建而成的路基较一次性新建而成的路基沉降演变过程复杂,沉降曲线形态由W型-U型-W型转变;老路基坡脚处地基侧向位移先向老路基一侧移动,再向新路基一侧移动而后又向内回缩。拓宽时应重视新老路基之间的相互作用;拓宽路基除应控制工后沉降外,同时应注意适当控制新路基施工期老路基的沉降及差异沉降。所获结论有助于工程实际沉降控制指标体系的合理确定、软基处治对策的科学选择。In order to study the deformation behaviors of expressway embankment over soft ground during the whole widening process,numerical models of newly built narrow embankment,newly built wide embankment and widened embankment were established based on the finite element numerical simulation.The developments of ground surface settlement,embankment surface settlement and ground lateral displacement of each model were compared and analyzed.The results show that widened embankment’s deformation behaviors are much more complicated than those of newly built embankment,and the settlement curve of widened embankment will change from W -type,to U -type,then to W -type.The ground under the old embankment toe lateral displacement moves to the side of old embankment,and then to the side of new embankment and later retracts.The interaction between old and new embankment should be taken seriously.Not only the post -construction settlement should be controlled,but also the settlement and differential settlement of old embankment during the new embankment construction should be focused on.These conclusions will be benefit in the determination of the settlement control index system and soft ground treatment measures.

关 键 词：软土地基 路基拓宽 变形特性 相互作用 有限单元法 

分 类 号：U418.8[交通运输工程—道路与铁道工程]