WSS注浆加固技术在隧道穿越群桩中的数值模拟分析及应用

Numerical Simulation Analysis of WSS Grouting Reinforcement Technology While Tunnel Passing Through the Pile Group and Its Application

隧道近距离穿越桥梁将不可避免地引起既有桥梁桩体附加应力和变形的增大,甚至引起既有桩体破坏和桥梁的垮塌。本文以北京地铁十号线为研究背景,数值模拟了隧道穿越国贸桥梁时群桩效应。结果表明,无WSS注浆加固条件下既有群桩桩顶沉降在7~20 mm,远远超过沉降控制标准;采取WSS注浆加固后,加固圈的存在减弱了隧道开挖对国贸桥桩体的影响,群桩桩顶最大沉降值降为6 mm,沉降值得到有效控制。最后针对工程实际提出了穿越过程中WSS注浆加固有效施工技术措施。其结论可供类似工程参考和借鉴。

Tunnel crossing the bridge at close distance inevitably causes the increase of additional stress and deformation of bridge pile, even causes the pile＇ s break and bridge collapse. In the light of the research background of Beijing Subway Line 10, this paper numerically simulated the pile group effect when the tunnel crossed the Guomao Bridge. The results showed that, under the condition of non-WSS grouting consolidation technology, the settlement of pile top was 7 to 20 mm, far more than allowed standard. After taking the measures of WSS grouting consolidation, the consolidation ring weakened the influence of tunnel excavation on the Guomao Bridge pile, the maximum settlement of the pile top was 6 mm, and the settlement value was effectively controlled. Finally, the effective construction technical measures of WSS grouting consolida- tion were put forward against the engineering practice, which could be used as a reference for similar projects.