Viscoplastic solutions of time-dependent deformation for tunnels in swelling rock mass considering stress release

作     者：Gengyun Liu Youliang Chen HyonChol Rim Rafig Azzam Gengyun Liu;Youliang Chen;HyonChol Rim;Rafig Azzam

作者机构：Department of Geotechnical EngineeringTongji UniversityShanghai200092China Department of Civil EngineeringUniversity of Shanghai for Science and TechnologyShanghai200092China Department of Engineering Geology and HydrogeologyRWTH Aachen UniversityLochnerstr.4-20 Haus AD-52064AachenGermany 

出 版 物：《Journal of Rock Mechanics and Geotechnical Engineering》 (岩石力学与岩土工程学报（英文版）)

年 卷 期：2023年第15卷第8期

页      面：2053-2071页

核心收录：

学科分类：08[工学] 080104[工学-工程力学] 0815[工学-水利工程] 0801[工学-力学（可授工学、理学学位）] 

基　　金：Authors are thankful to Dr.Chen Xu of Ningbo University for his instructive discussions.The authors are also grateful for the support provided by the National Natural Science Foundation of China(Grant Nos.41972274 and 42207176) Ningbo Natural Science Foundation(Grant No.2022J116)for this research work 

主　　题：Sichuan-tibet railway Viscoplastic deformation Stress release Fractional model Tunneling engineering 

摘      要：Excavation and control of tunneling responses in swelling soft-rock tunnels of Sichuan-Tibet railway under seepage conditions were *** this,a fractional viscoplastic(FVP)model for swelling soft rocks was established by introducing Abel dashpot and unsteady viscosity coefficient,considering additional swelling deformation and damage of rock caused by humidity *** view of the FVP model,the viscoplastic deformation solutions for rock mass surrounding tunnel under seepage conditions were derived and long-term mechanical responses of swelling rocks upon tunnel excavation were ***,a stress release coefficient considering seepage and creep was proposed,based on which control responses considering stress release and failure mechanism of stress release measures were *** results showed that:(i)The one-dimensional(1D)FVP model has a good application for swelling rock and the three-dimensional(3D)FVP model could well describe the whole creep process of rock mass despite a much higher creep attenuation rate in the first stage of creep;and(ii)An appropriate stress release and deformation of surrounding rocks could effectively reduce the supporting ***,upon a large stress release,the radius of plastic region could increase significantly,and the strength of the surrounding rock mass decreases *** proposed solution could provide a theoretical framework for capturing the excavation and support responses for tunneling in swelling rock mass in consideration of time effect.