随机变量相关性对隧道二衬作用效应的研究

Study on Random Variables Correlation to the Internal Forces of Tunnel Secondary Lining

地下工程中岩土层自身的随机性、模糊性及不确定性因素使得隧道工程面临着较大风险。随着隧道工程的蓬勃发展,如何提高隧道工程衬砌结构的安全度、降低工程结构风险措施的研究显得尤为重要。然而,直至目前仍然没有系统、科学的方法来降低隧道工程风险。本文以可靠度理论为基础,同时基于ANSYS软件中的PDS技术,对隧道工程中二衬结构的某些参数的相关性入手,探讨随机输入变量的相关系数对二衬结构的作用效应的影响。研究成果表明:忽略随机变量之间的相关性将对计算结果造成很大误差;二衬作用效应与计算参数的相关系数之间存在一定的线性关系;隧道设计中应当考虑计算参数间的相关性才能使工程设计更贴近真实情况。

The tunnel engineering has higher risk because of randomness,fuzziness and uncertainty in rock and soil layers. The tunnel engineering has developed very well now. How to improve the safety of tunnel lining structure and reduce the risk of engineering structure is important. Until now,there is no systematic and scientific method to reduce the risk of tunnel engineering. it’s based on reliability theory and PDS technology of ANSYS in this paper,considering the relationship between degree of reliability and some parameters of the secondary lining structure,then the secondary lining structure influenced by correlation coefficients of random variables have been discussed. Research results show that ignoring correlations between random variables will cause great error to the calculation results;there is a linear relationship between the secondary lining effect and correlation coefficients of calculating parameters;the engineering design is close to the real situation when calculating parameters considered in tunnel design.