地震荷载作用下桩承式加筋路堤动力响应分析

Dynamic Response on Geosynthetic Reinforced and Pile Supported Embankment Under Seismic Loads

桩承式加筋路堤具有工期短,成本低以及沉降变形小等优点,在工程中得到了广泛应用。为了研究地震荷载作用下桩承式加筋路堤的动力特性,建立了桩承式加筋路堤的数值分析动力模型,分析了水平地震波El-Centro作用下桩承式加筋路堤的动力响应。同时,研究了路堤加速度、动剪应力和路堤动位移等动力特性,分析了CFG桩和土工格栅的内力峰值分布。最后,对土工格栅抗拉模量和桩间距进行了参数分析,研究了水平地震荷载作用下土工格栅抗拉模量和桩间距对桩承式加筋路堤动力响应特性的影响。数值分析结果表明:桩承式加筋路堤在右坡面接近坡脚处,剪切应变增量最大;增大格栅抗拉模量能增强桩承式加筋路堤的抗震性能,而且对增强竖向地震稳定性比水平向地震稳定性效果更明显。

Geosynthetic reinforced and pile supported（GRPS） embankment has been constructed increasingly owing to its rapid construction,low cost,and small total and differential settlement.In order to investigate the dynamic behaviors of GRPS embankment under the seismic loads,the dynamic model are conducted using FLAC.This paper focuses on the dynamic response of the embankment under the horizontal earthquake wave of El-Centro.Simultaneously,the acceleration,dynamic shear stress and displacement have also been studied,so does the peak distribution of internal force in the CFG piles and geosynthetic.Finally,the key influencing factors including the tensile stiffness of geosynthetic and the pile spacing have been analyzed on the dynamic response of GRPS embankment under seismic loads.The result shows that the greatest increment of the shearing strain is at the right embankment toe.The tensile stiffness of the geosynthetic has a significant influence on the anti-seismic performance of GRPS embankment.