双侧壁导坑法隧道不同施工阶段变形分析

以武汉市光谷一路—高新四路排水通道工程为例,运用有限元分析软件PLAXIS,对双侧壁导坑法隧道的施工过程开展数值模拟,重点对不同施工阶段产生的地表沉降和拱顶沉降等进行分析.计算结果表明:在隧道开挖过程中,洞周土体均发生不同程度的变形,不同施工阶段对应的地表横向沉降槽形状基本与Peck曲线相近,且地表沉降的最大值在隧道轴线对应的地表处,其中S6a、S6b区段施工完成后发生的地表沉降最大值分别为2.1、1.2 mm;另一方面,S6b、S6a区段双侧壁导坑法的拱顶沉降最大值分别为6.9、2.8 mm,拱底隆起最大值分别为7.9、7.3 mm,且最大值发生位置均在隧道轴线对应的拱顶及拱底处.

Deformation Analysis of Double-wall Tunnel in Different Construction Stages

Based on the drainage channel project of Wuhan Guanggu No.1 Road - Gaoxin No.4 Road, the finite element analysis software PLAXIS is used to carry out numerical simulation of the construction process of double-wall tunnel, and the surface settlement and vault settlement generated in different construction stages are analyzed . Calculation results show that: during the process of tunnel excavation, the soil around the tunnel occurred different degree of deformation. The shape of surface lateral settlement groove corresponding to different construction stages is basically similar to Peck curve, and the maximum surface settlement is at the surface corresponding to the tunnel axis. The maximum surface settlement of S6a and S6b sections after construction is 2.1mm and 1.2mm respectively. On the other hand, in S6b and S6a sections, the maximum settlement of the vault and the maximum uplift of the arch bottom are 6.9mm and 2.8mm respectively, and the maximum value occurs at the corresponding vault and the bottom of the tunnel axis.