地铁盾构隧道下穿沪宁城际铁路无砟轨道路基的影响研究

以无锡地铁3号线盾构隧道下穿沪宁城际铁路路基为背景,采用理论分析结合有限元单元法,探讨对铁路路基采用混凝土板+钻孔桩+CFG桩联合加固措施的有效性以及加固效果,并将计算结果与施工监测数据进行对比,结果表明:采用加固方案后,当地层损失率为0.5%时,双线贯通后沪宁城际铁路路基的最大沉降变形为0.712 mm,路基加固后的最大沉降是未加固时最大沉降值的11.3%。因此,预加固措施能够有效控制地铁盾构隧道下穿沪宁城际铁路路基过程中产生的沉降变形,满足高速铁路运营安全。

Influence of Shield Tunneling on the Ballastless Track Subgrade of Shanghai-Nanjing Intercity Railway

In the background of the construction of Wuxi Metro Line 3 shield tunnel under-passing Shanghai-Nanjing Intercity Railway in Wuxi,the effectiveness and reinforcing effect of concrete slab+bored pile+CFG pile composite structure was discussed by theoretical analysis and finite element method.The calculation results were compared with the construction monitoring data.Results show that when the layer loss rate is 0.5%,the settlement of ballastless track subgrade after reinforcement is 11.3%of unreinforced,and the maximum settlement of subgrade is 0.712 mm.Therefore,during the construction of shield tunnel under-passing Shanghai-Nanjing intercity railway,the pre-reinforcement scheme can effectively control the settlement and deformation,and guarantee the operation safety of high-speed railway.