京张高铁八达岭铁路隧道衬砌极限状态设计方法研究

Research on the Design of Lining Limit State Method for Badaling Railway Tunnel of Beijing-Zhangjiakou High-speed Railway

由于荷载和材料参数的随机性,采用相同安全系数设计的隧道结构可靠性并不一致。基于概率理论的极限状态设计方法可消除上述问题,并可定量地描述隧道结构的可靠性,是未来隧道结构设计方法的发展方向。理解极限状态法在设计理念、设计参数、计算公式及评价标准等方面与传统方法的区别是正确应用该方法的前提。以京张高铁八达岭铁路隧道衬砌结构设计为例,依据《铁路隧道设计规范(极限状态法)》,针对一般隧道衬砌及大跨度衬砌结构,分别给出极限状态设计方法及流程,详细说明不同极限状态应采用的荷载组合、评价标准及注意事项。

Due to the randomness of load and material parameters,the reliability of tunnel structure designed with the same safety factor may not be the same.The limit state design method based on probability theory can eliminate the above problems and quantitatively describe the reliability of tunnel structure,which is the development direction of tunnel structure design method in the future.Understanding the differences between the limit state method and the traditional method in design concepts,design parameters,calculation formulas,and evaluation standards is a prerequisite for the correct application of the method.Taking the lining structure design of the Badaling Railway Tunnel of Beijing-Zhanghai High-speed Railway as an example,and according to the relevant provisions of Code for Design of Railway Tunnel(Limit State Method),this paper puts forward limit state design method and process of railway tunnel lining,and elaborates on load combination,evaluation criteria and precautions for different limit states.