拟建的大理-瑞丽铁路穿越横断山区南段的滇西南地区,地形、地貌和地质条件都极为复杂,其中高黎贡山深埋超长隧道的工程稳定性问题一直是困扰铁路选线、设计和施工的重大工程难点.针对不同形态隧道断面可能对高黎贡山超长隧道工程稳定性产生的影响问题,在充分综合该区野外地质调查、地应力测量、岩石力学实验等成果与资料的基础上,利用ANSYS有限元应力分析软件对不同形态隧道断面的应力分布进行了有限元计算,给出了应力分布图像,分析了断面应力分布的特点和断面形状对应力分布的影响.同时,计算了围岩的应力与强度比,对2种不同断面的围岩稳定性进行了分析对比,最后根据分析结果对不同隧道断面形态下的隧道稳定性进行了综合评价,并据此提出了铁路隧道断面设计与施工中应重点关注的问题.%The Dali-Ruili railway constitutes the critical part of the Trans-Asian railway system. It runs through the southern stretch of the Hengduan Mountains with complicated topographic and geological conditions. The engineering stability of the Gaoligong Mountain deep-lying extra-long tunnel has long been a thorny problem affecting route choice and road construction. Based on regional geology, stress measurements, and rock mechanism, the authors conducted finite element calculation of the stress distribution of tunnel profiles, created stress-distribution images, and evaluated the impact of the shape of the tunnel profile on stress distribution, by using ANSYS software. The authors also made an analysis of country rock stability from different tunnel profiles and calculated the ratio between the strength and the stress of the wall rock. In the end, a comprehensive estimation is made concerning tunnel stability on different profiles, and some key problems are put forward which deserve attention in tunnel design and construction.
展开▼
