深切割地形浅埋偏压隧道围岩压力的计算方法

公路隧道设计规范给出了浅埋偏压隧道围岩压力的计算方法,但有其适用条件。以规范方法为基础,首先推导出采用规范方法需满足的临界边缘宽度;然后通过假定挡土墙模型,推导出深切割地形浅埋偏压隧道浅埋侧侧压力的解析解;最后以张涿高速公路李家堡隧道为工程依托,结合现场围岩压力量测,将方法与规范方法的计算结果进行对比,发现方法比规范方法更接近实际。研究结果为类似工程的设计及施工提供参考价值,对现行规范进行有益的补充。

Calculation Method of Surrounding Rock Pressure for Shallow and Unsymmetrical Tunnel Under Deep Valley Terrain

Code for design of road tunnel provides the calculation method of surrounding rock pres- sure for shallow and unsymmetrical tunnel,however, which has the applicable condition. Based on code method, the critical edge width is derived which need satisfy when using code method. Then, by assuming the retaining wall model, the analytical solution of lateral pressure for shallow and unsymmetrical tunnel under deep valley terrain is deduced. At last, take Lijiabao tunnel belonging to Zhangzhuo highway as en- gineering relying and combine with the field measurement of surrounding rock pressure, the conclusion is drew that the paper method is more close to the reality than code method by the comparison of two meth- ods. The study results provide references with the design and construction of similar engineering and offers favorable supplement for the current code.