地铁车站大断面风道施工对地面建筑物的影响及控制

在城市隧道穿越工程施工前,应制定详细的建筑物安全性控制程序,其中包括建筑物安全现状评估、隧道施工对建筑物影响预测及施工过程控制、工后评估及结构状态恢复等.北京地铁5号线天坛东门站西北风道大断面风道施工需要在松散不良地质条件下穿越天坛公园＂青山居＂仿古建筑及旅游服务部等建筑,施工难度大,施工风险极高.根据建筑物安全性控制的要求,对地铁隧道施工的影响进行了数值模拟预测及对比分析,阐述地层变形模式和相应的控制措施.另外,为严格控制地面沉降及建筑物安全,在对该工程特点和控制方案系统分析的基础上,提出采用树根桩隔断墙和洞内超前注浆、掌子面注浆及控制开挖、墙基下方地层注浆加固等综合技术,有效控制了地面沉降和建筑物沉降,保证了隧道施工顺利完成.

Influence Analysis and Its Control of Surface Buildings During Construction of Large-Section Wind Tunnel of Subway Station

Before the crossing project of tunnel in the city, a program about the control of the structure security, including several main aspects such as the assessment of the security status quo about building, the prediction of the effect tunnel construction on the settlement of building, the control of construction process, the assessment after tunnelling and the restoration of structure status, should be elaborate. The large-section construction of the northwest ventilation channel of Tiantandongmen sub- way station on Beijing Subway Line 5 needs to across loose and adverse geological conditions under ＂Qingshanju＂ antique architecture, travel services division and so on in Tiantan Park. Construction is very difficult and the risk is extremely high. According to the request of the control procedure about building security, numerical simulation of prediction and comparative analysis is developed on buildings affected by construction of subway tunnel; thus strata deformation mode and the corresponding sides, in order to control the surface settlement strictly and keep buildings uses partition wall with root pile, grouting reinforcement in footing surface ing face grouting and excavation control, is proposed to bring surface and These methods ensure the tunnel construction can be carried out smoothly control measures is expounded. Be- safe, integrated technology, which , pre-grouting in tunnelling, workbuilding settlement under control.