地下负二层施工对既有隧道结构的影响

为分析地下工程近接施工过程中对已建地下结构的位移及受力影响情况,以某地下商业街近接既有地铁隧道施工为依托,考虑既有地铁隧道结构存在的影响,对拟建的地下商业街负二层结构在施工过程中对负一层结构的影响进行研究。以地下商业街负一层结构施工结束为初始应力状态,通过有限元软件MIDAS/GTS对负二层结构的施工过程进行数值模拟,分析负一层结构的位移及内力变化情况,以及施工过程的安全可行性。分析结果表明,负一层地下结构位移及弯矩的变化均在合理范围内,且既有隧道的存在可以减少负一层结构受负二层施工的影响。

Influence of negative second structure construction considering existing tunnel

To analyze the change of displacement and stress in the approaching construction process of underground engineering,based on the underground commercial street approaching the existing metro tunnel structure, considering the influence of the existing metro tunnel structure, the influence on negative one structure was discussed during the construction process of proposed underound commercial street negative second structure. The end of the negative one structure construction was considered as the initial stress state, the construction process of the negative second structure was simulated by finite element software MIDAS/ GTS, and the changes of displacement and stress for the negative one structure, and the safety and feasibility during the approaching construction process were analyzed.The results show that the changes of displacement and moment of the negative one structure are in the reasonable range, and the existing tunnel can reduce the influence of the negative second structure construction on the negative one structure, and play a beneficial role.