Study on the strength theory effect of rock-support interaction in deep buried tunnels
PAN Rui
REN Mingyang
Abstract：In order to study the strength theoretical effects of the interaction between surround-ing rock and support in deep buried tunnels,this paper systematically compared and analyzed six typical strength criteria in geotechnical engineering,constructed an axisymmetric plane strain mechanics model considering the strain softening behavior of rock mass and nonlinear correlation flow law,and proposed the solution method of"increasing support load method".Through numerical examples,the influence of intermediate principal stress and different strength criteria on the interaction between surrounding rock and support was analyzed.The research results indicate that the degree of consideration of intermediate principal stress is the fundamental reason for the differences in the calculation results of different criteria.The tun-nel stability evaluated by the six criteria from high to low is circumscribed Drucker-Prager cri-terion,Generalized Lade-Duncan criterion,Mogi-Coulomb criterion,Generalized Matsuoka-Nakai criterion,Unified Strength Theory(0.5),and Mohr-Coulomb criterion;The degree of influence of support timing on the stability of surrounding rock varies significantly with differ-ent criteria,with the Mohr-Coulomb criterion being most affected by support timing and the circumscribed Drucker-Prager criterion being the least affected.In practical engineering,it is recommended to use four types of criteria:Generalized Lade-Duncan,Mogi-Coulomb criterion,Generalized Matsuoka-Nakai criterion,and Unified Strength Theory(0.5).circumscribed Drucker-Prager criterion is not recommended,and Mohr-Coulomb criterion can be used for low intermediate principal stress or jointed strata.The research results can provide important theo-retical basis for the stability assessment of surrounding rock in deep buried tunnels,the design of support structures,and the optimization of construction timing.
Keywords：deep buried tunnelrock-support interactionstrength criteriaintermediate prin-cipal stressstrain softening
Publication Date：2025-07-30
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：14( 811-824 )