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Using the numerical simulation model, the effects of the surrounding rock deformation capacity, lining concrete label, backfill grouting pressure, and grouting stone deformation capacity on the hydraulic head of the hydraulic pressure tunnel lining and the joint bearing ratio of the surrounding rock and lining were analyzed. The result showed that: the elastic modulus of the surrounding rock had a significant effect on the joint bearing ratio of the surrounding rock and the lining. When the higher the elastic modulus of the rock mass, the greater the load shared. The effect of the lining concrete label and the grouting stones was small, and the backfill grouting pressure had no effect basically. The modulus of surrounding rock and grouting stones, grouting pressure increased, and the internal water head required for lining cracking increased. The influence of elastic modulus of surrounding rock and backfill grouting on cracking head was more obvious, but due to the concrete rank increase, the lining load sharing ratio increased, and the lining cracking head gradually decreased. The research results could provide support for the design of hydraulic pressure tunnel lining and the reasonable selection of grouting parameters. [ABSTRACT FROM AUTHOR]

Soft rock under high stress is prone to occur large deformation, and jamming disasters often encounter when TBM passes through such stratum. Currently, there is no classification standard that can directly guide TBM construction adaptability for large-deformed surrounding rocks. Analyzing the advancing state of TBM, the deformation of surrounding rock and the pressure on the shield were regarded as the main indexes. The contact state of the surrounding rock and TBM was distinguished according to the relationship between the rock deformation and overcut size; and the state of shield stress was distinguished according to the relationship between the shield friction and TBM ultimate thrust. Moreover, considering the accessibility and universality of surrounding rock classification, the classification standard of TBM construction adaptability for large deformation surrounding rock was established according to the potential jam status of TBM. The classification standard was applied to a specific project to verify its reasonability. The results showed that the TBM construction adaptability classification for large-deformed surrounding rock required taking rock deformation and shield stress into consideration comprehensively. The proposed standard could guide projects directly and effectively to avoid jamming disasters. [ABSTRACT FROM AUTHOR]