热力隧道上穿既有地铁6号线隧道方案比选

随着城市地下轨道交通的发展,上穿既有线路的情况时有发生.由于新线穿越既有线路不可避免地会引起既有隧道结构产生附加应力和沉降,而地铁运营对变形又有着非常严格的控制标准,所以选择最合适的施工方法十分重要.以热力隧道上穿北京地铁6号线东四站—朝阳门站区间工程为依托,通过三维数值模拟软件FLAC3D分别对从左侧竖井向右侧竖井开挖热力隧道;右侧竖井向左侧竖井开挖热力隧道;从两侧竖井向中间开挖热力隧道三种施工方式进行数值模拟分析.并从三种施工方案中比选出对既有地铁运营区间影响最小的施工方法.通过进行安全分析可以表明:从两侧竖井向中间开挖热力隧道能有效减小地铁6号线运营区间的变形,为更加合理的施工提供了重要依据.

Schemes of Thermal Tunnel through Existing Subway Line 6

With the development of city underground rail transit, crossing the existed line occurs from time to time. The new line will inevitably lead to cross the existing tunnel structure to generate additional stress and settlement, and the deformation of subway operation and control standards are very strict, so the choice of the most appropriate construction method is very important. In this paper, taking the thermal power tunnel crossing through the section between Dongsi and Chaoyangmen station engineering in Beijing Metro line 6 as the basis, three excavation methods—from the left to the right side of the heat tunnel shaft excavation;on the left to the right side of the tunnel excavation tunnel heat;from both sides to the middle shaft—are simulated by software FLAC3D . And from the three construction schemes one is selected to minimize the effect of both the construction method of subway operation interval. Through the security analysis it shows that the minimum deformation of tunnel excavation in Metro Line 6 is the excavation from both sides to the middle of the range of vertical shaft, and it provides an important basis for the more reasonable construction.