公路工程

选取重庆地区某高速公路双连拱隧道为工程背景,采用数值计算与现场实测研究不同开发方法的适应性并对施工薄弱环节提出相应优化和加固措施,可得结论:1和导洞法相比,采用台阶法隧道洞周和中隔墙上部出现一定范围带状分布的拉应力区;2导洞法开挖围岩剪应力应力集中分布在中隔墙两端和隧道拱肩,台阶法开挖围岩剪应力集中范围变小,但应力值增幅较大;3双连拱隧道拱顶沉降集中在中隔墙和隧道拱顶上部,导洞法引发拱顶沉降量值小于台阶法;4采用导洞法开挖,隧道底部隆起位移量值和分布范围均得到有效控制;5双连拱隧道中墙成为确保围岩稳定性关键部位,在设计与施工中采取相应的加固措施;6现场实测与数值计算结果位移发展规律相一致。

Taking multi-arch tunnel in Chong-Qing highway as the project background,The Adaptability of different construction method is performed by numerical calculation and site measurement,the optimization and strengthening measures are proposed for weak processes. The results are showed that: 1 Compared with pilot method,the zonal of tension stress zone is appeared range tunnel edge on the top of crown and middle wall; 2 the shear stress concentration is distributed of amphi-middle wall and spandrel. The range of shear stress concentration is decreased and the shear stress value is increased large-sized by bench method. 3the crown settlement of multi-arch tunnel concentration in the top of middle wall and crown,the value of crown settlement by pilot method less than bench method; 4 the displace value and distribution range of the bottom uplift are brought under effective control by pilot method;5 the middle wall construction is become key step sequence for stability of surrounding rock,the corresponding reinforcement measures should be performed by design and construction; 6The variation of the site measurement basically tallies with the numerical calculation.