盾构下穿新建高铁站房桥桩施工方案优化设计及风险分析

Optimal Design and Risk Analysis of Shield Structure through Bridge Piles of Newly Built High Speed Railway Station

以合肥地铁10号线下穿某新建高铁站为研究对象,对工程数据及设计资料进行分析和整合,通过PECK公式对工程数据进行理论计算。同时,建立“桩-土-隧道”三维有限元模型,通过模拟结果与理论计算结果的对比,验证了模拟的准确性。数值模拟试验结果表明,虽然隧道最小净距开挖引起的地表沉降与原定施工方案相差较小,但其导致的桩底受力要显著小于原方案,且差距达近2倍。因此,本文建议应合理缩小左右线隧道净距,以达到在控制土体沉降值变化较小情况下,有效减小桩基底部的受力的目的。同时,针对工程可能出现的风险情况进行综合分析,并针对风险情况提出了对应的解决措施,以期为工程的实际施工提供参考。

Taking Hefei Metro Line 10 under a new high-speed railway station as the research object,engineering data and design data were analyzed and integrated,and theoretical calculation of engineering data was carried out through PECK’s formula.Meanwhile,a three-dimensional finite element model of“pile-soil-tunnel”is established,and the accuracy of the simulation is verified by comparing the simulation results with the theoretical calculation results.The numerical simulation results show that although the surface settlement caused by the minimum clear distance excavation of the tunnel is less than the original construction plan,the resulting pile bottom force is significantly less than the original plan,and the difference is nearly twice as large.Therefore,suggests that the net distance between the left and right line tunnels should be reasonably reduced to achieve the purpose of effectively reducing the force at the bottom of the pile foundation under the condition of controlling the small change of soil settlement value.At the same time,a comprehensive analysis is made for the possible risk situation of the project,and corresponding solution measures are proposed for the risk situation,in order to provide reference for the actual construction of the project.