Dominant causal factors of failure performance of cross-jointed segmental lining

To understand the failure behavior of segmental linings with inclined bolts, this study proposes a group of interrelated contribution-measuring scales (CMS) to evaluate the contributions and relative importance of causal factors. In the field of failure behavior research, parametric analysis is typically used to weight the sensitivity of a system to hypothetical changes in specific parameters; however, the true contribution of influencing factors to the system cannot be assessed via this sensitivity analysis. Identifying and ranking the contributions of causal factors to system effects is important for understanding as to why an incident occurs. To this end, this study first analyzes the member force breakdown structure of a crossed-jointed segmental lining, followed by the evaluation principle, evaluation indices and criteria, and analytical calculation method of the CMS. Finally, the CMS is used to analyze the failure behavior of a cross-jointed segmental lining. The results indicate that: (1) Based on the moment search method and moment separation algorithm, the CMS can be calculated analytically, and the maximum error between the analytical method and numerical solution does not exceed 3 %. (2) For the cross-jointed lining, the magnitude of the joint effect on the lining moment is related to the attenuation of the rotational stiffness of the joint and the system nonlinear characteristics are governed by the dominant joints. (3) Using the CMS, the structure and its variation in the mechanical response of the segmental lining system in the failure history can be measured and represented effectively and the governing variables can be identified quantitatively to simplify the understanding of the system failure behavior.