成渝高速公路扩能改造工程对新双碑隧道的影响研究

Study on the Impact of the Capacity Expansion and Renovation Project of the Chengdu-Chongqing Expressway on Xinshuangbei Tunnel

为缓解成渝高速公路中梁山隧道段交通拥堵状况,对该段公路进行扩能改造。拓宽段路堑位于在建渝黔铁路新双碑隧道上方,其防护桩桩底距离隧道拱部净距仅为4.3 m。为评估路堑施工对铁路隧道的影响,采用数值分析方法模拟上方高速公路施工的各步骤,计算出各阶段铁路隧道内力和变形情况,论证了既有隧道上方小净距施工方案的可行性,并制定了相关保护措施,为方案的评审和顺利实施提供了依据。

In order to ease the traffic congestion in the Zhongliangshan tunnel section of the Chengdu-Chongqing Expressway,the particular section is to be expanded and renovated to increase its capacity.The cutting section to be widened is located above the Xinshuangbei tunnel of the Chongqing-Guiyang Railway,and the clearance distance between the bottom of the protection piles and the tunnel arch is only 4.3 m.In order to evaluate the impact of the cutting construction on the railway tunnel,this paper adopts the numerical analysis method to simulate the various construction steps of the renovated expressway above the railway tunnel,calculates the internal force and deformation of the railway tunnel at each construction stage,demonstrates the feasibility of the construction plan of the renovated expressway above the existing tunnel with small clearance distance,and prepares relevant protection measures,providing a basis for the review and smooth implementation of the plan.