竹筋格栅加筋山区挖填路基受力变形研究

Study on the stress deformation of bamboo geogrid reinforcement in digging and filling roadbed in mountainous areas

利用我国西部山区的竹材作为挖填路基的加筋材料,对湘西楠竹筋材的抗拉、抗弯强度进行测试,并与传统加筋材料的力学性能进行比对;基于Pasternak模型对挖填路基进行简化,对竹材加筋挖填路基抗弯变形性能展开研究;利用FLAC3D有限差分软件建立加筋挖填路基三维模型,就加竹筋格栅、加土工格栅及不加筋3种工况下的路基顶面差异沉降进行对比分析。研究结果表明:竹材能满足规范对筋材力学性能的要求;竹筋格栅加筋能有效减少路基顶面差异沉降,且其加筋效果优于土工格栅。研究成果可为控制挖填路基填挖结合部差异沉降提供技术支撑,为挖填路基的设计、施工提供参考。

In order to make use of bamboo as reinforcement material for excavated and filled subgrade in western mountainous areas of China,the tensile and bending strength of phyllostachys pubescens reinforcement in West Hunan was tested and compared with mechanical performance of traditional reinforcement material.Excavated and filled subgrade was simplified based on Pastemak model to study the Bamboo reinforced excavated and filled subgrade bending deformation performance;The reinforced excavated and Filled^3D model was established based on finite difference software FLAC3D,the comparison analysis was made for differential sedimentation on the top of subgrade in such three cases as bamboo geogrid,geogrid and no reinforcement was installed on the excavated and filled joint.The result indicates that bamboo geogrid can meet the requirement of existing standard for mechanical performance of reinforcement;bamboo geogrid reinforcement can effectively reduce the differential sedimentation of the subgrade top surface,and the reinforcement effect of bamboo geogrid was superior to that of geogrid.This can provide technical support for controlling differential settlement at the joint of excavation and filling subgrade,and provide important reference for design and construction of excavation and filling subgrade.