双线小净距隧道中岩墙力学特征及加固措施研究

采用二维弹塑性数值计算方法,对Ⅲ,Ⅳ,Ⅴ级围岩条件下平行布设的双洞隧道中夹岩墙受力、变形特点随隧道间距变化的情况进行了研究。研究结果表明,对于两隧道间距较小的小净距隧道,中夹岩墙的受力、变形极为不利,是设计、施工和监控量测的关键部位。同时研究了不同隧道埋深以及不同岩柱加固措施对小净距隧道中夹岩墙受力、变形特点的影响,为小净距隧道的支护设计、开挖方式、岩墙加固方式选取以及现场监控量测方案制定等提供指导。

Study of mechanical behavior and reinforcing measures of middle rock wall of parallel tunnel with small interval

Applying 2D elastoplastic numerical calculation method and under the conditions of surrounding rocks of grades Ⅲ, Ⅳand Ⅴ, the characteristics of stress and deformation of middle rock wall in parallelly laid twin tunnel are studied. The findings show that the stress and deformation of middle rock wall are adverse due to the parallel tunnel with smaller interval; and these locations are very critical for design, construction and monitoring measurements. At the same time, the effects of different buried depths and different reinforcing measures of rock wall on stress and deformation of the tunnels with small interval, are also studied, so as to provide guidance for design of support, selection of excavation method, reinforcing method of rock wall and monitoring plans.