基坑临近运营盾构隧道施工影响分析

ANALYSIS OF THE IMPACT OF SHIELD TUNNEL CONSTRUCTION NEAR THE OPERATION OF THE FOUNDATION PIT

随着城市建设、地铁的快速发展,随着新建基坑工程临近运营盾构隧道施工的工程增多,风险工程控制要求也越来越高。文中结合长三角软土地区某深基坑工程,采用有限元软件MIDAS GTS模拟新建基坑施工对既有盾构隧道及周边环境的影响,准确合理的分析和预测基坑、隧道及两者相互影响的趋势,通过合理的风险处理措施使隧道结构位移、轨道结构位移、隧道结构内力、基坑整体稳定等均在控制值内,确保既有运营隧道的安全,为设计、施工过程中采取针对性的保护措施提供有效依据,也为长三角等软土地区其他不同工况的深基坑临近施工工程提供有效的参考。

With the rapid development of urban construction and subways,the construction of shield tunnels near the operation of new foundation pit projects has increased,and the requirements for risk engineering control have be⁃come higher and higher.Combined with a deep foundation pit project in the soft soil area of the Yangtze River Delta,this paper uses the finite element software MIDAS GTS to simulate the impact of new foundation pit construction on the existing shield tunnel and surrounding environment,accurately and reasonably analyzes and predicts the trend of foundation pit,tunnel and the mutual influence of the two,and makes the tunnel structure displacement,track struc⁃ture displacement,tunnel structure internal force,and overall stability of the foundation pit are all within the control value through reasonable risk treatment measures,so as to ensure the safety of the existing operating tunnel.It pro⁃vides an effective basis for taking targeted protection measures during the construction process,and also provides an effective reference for the adjacent construction of deep foundation pits under different working conditions in soft soil areas such as the Yangtze River Delta.