大跨度浅埋隧道工程地质特征及自稳能力分析

结合沈大高速公路改扩建工程韩家岭大跨度浅埋隧道,通过地质条件的现场调查,研究了该工程关键地段的地质特征,分析了采用新奥施工方法注意事项以及对工程稳定性的影响,提出了施工中充分发挥围岩自稳能力的具体措施.工程实践表明,韩家岭隧道是大跨度隧道、地质工程条件复杂,施工过程中,必须加强对岩体结构面和变形的监测,及时调整施工方法和施工工艺.尤其是加强重点部位自稳结构的监测和调整,充分发挥围岩自稳能力.所提出的建议方法为类似工程施工建设提供了借鉴.

Self-Stability Analysis and the Geological Characteristics of Long-Span and Shallowly-Buried Tunnel

The shallowly-buried long-span Hanjialing tunnel is an integral part of the expansion project of Shenyang-Dalian expressway in Northeast China. Based on the field survey of geological conditions, the geological characteristics of key positions of the tunnel were investigated, especially how the new Austrian tunneling method (NATM) construction process will affect its stability. Some measures are proposed to take so as to play fully the role of host rock in construction process. The practice showed that the geological/engineering conditions of the long-span tunnel are very complex, and it is of importance to monitor rocks structural plane and deformation and to readjust timely the construction schedule and relevant technologies. It is stressed that the self-stability mechanism of key positions should be monitored and controlled carefully so as to play fully the role of self-stability of hast rock. What the measures proposed to take and relevant experience will benefit the construction of the other similar projects.