某选煤厂主洗车间基坑边坡稳定性破坏分析

Analysis Foundation Pit Slope Instability of the Coal Preparation Plant Main Workshop

基坑土方开挖过程中北侧边坡出现裂缝,导致北侧基坑出现失稳。利用理正超级土钉软件,对本工程基坑北侧土钉墙支护进行验算,基坑实际开挖过程进行校核、验算;采用有限元软件ABAQUS建立基坑北侧开挖有限元模型,计算基坑开挖过程中失稳的临界状态及基坑顶部的变形趋势。通过以上分析表明,施工单位在上层土钉注浆体及喷射混凝土面层未达到设计强度70%的情况下即开挖下层土方,且开挖深度、长度均不符合原设计要求,是造成基坑北侧边坡出现裂缝的主要原因。

The north slope of certain foundation pit emerges cracks during excavation process,results the foundation pit unsteadiness.Using super soil nailing software LI Zheng,checks the stability of soil nailing for the north slope,checks the foundation pit actual excavation process;the finite element model of the north foundation pit excavation is established by using the finite element software ABAQUS,calculates unsteadiness critical state and deformation tendency of the top of the foundation pit during the process of foundation pit excavation.Through the above analysis shows that it is the main reason causing cracks on the north slope of foundation pit that construction organization excavated the lower earthwork when the upper soil nailing cement grout and shotcrete layer had not reached the design strength of 70%,and the excavation depth,length are not in conformity with the requirements of the original design.