排洪隧洞爆破荷载对填埋场防渗结构的影响分析OA

Based on the Xiaping Solid Waste Landfill Project in Shenzhen,taking the western section of the flood discharge tunnel as the research object,selecting the tensile deformation or tensile stress of the HDPE membrane as the safety control index,and adopting the numerical simulation method to evaluate the influence of tunnel excava-tion blasting vibration loads on the stability of the seepage-proof structure of the landfill.The research results indi-cates that the stress waves generated by blasting propagate outward approximately along the tunnel wall in a circular pattern,with reflection and refraction occurring at the interface between the surrounding rock and the waste pile;The tensile stress of the HDPE membrane is mainly controlled by static loads.The tensile stress increment caused by blasting loads is very small.And the HDPE membrane is far from yielding failure.Additionally,the maximum addi-tional stress caused by blasting in the waste fill is relatively smaller,and the ground vibration velocity is lower than the vibration control velocity,and the blasting loads have a minor impact on the stability of the waste pile.Generally,under the blasting construction scheme,the HDPE membranes of the landfill is in a safe state.However,the one laid on the surface slopes are subjected to the maximum stress with the highest risk.Therefore,It is recommended to take enhanced monitoring measures during the actual construction.