铁道科学与工程学报2024，Vol.21Issue(6)：2396-2405,10.DOI:10.19713/j.cnki.43-1423/u.T20231345
基于黏聚力弱化边界面模型的深部洞室响应分析
Analysis on response of deep circular tunnel based on a cohesion-weakening bounding surface model
摘要
Abstract
Surrounding rock of deep tunnels may exhibit certain type of hardening-softening response under the coupling effect of in-suit stress and excavation unloading.This feature would have a strong influence on the evaluation of the opening response and the design of the support structure.In order to capture the hardening-softening response of deep surrounding rock after excavation,a cohesion-weakening bounding surface constitutive model was developed within the framework of bounding surface theory.It was derived by introducing a cohesion-weakening mechanism and a modified Rowe stress-dilatancy rule.Prediction errors caused by the uncertainties in yield surface parameter measurements were avoided by simplifying the yield surface-peak strength-residual strength system in classical constitutive models to the initial(peak)bounding surface-residual bounding surface in the proposed model.Controlling ordinary differential equations(ODEs)of the stress distributions around the deep circular tunnel were derived based on the incremental stress-strain relationship of the proposed constitutive model.The Hencky strain was introduced to capture large deformations and an auxiliary variable was introduced to reduce the controlling equation system.The ODEs were solved under given boundary conditions such as earth pressure,and the stress distributions of the deep circular tunnel were calculated and validated by comparison with existing solutions.In addition,the stress distributions of the deep tunnel under different combinations of support pressures and earth pressure were derived and investigated.Furthermore,the ground response curve was derived by exploiting the stress distribution solution in this paper and the influences of residual cohesion are also investigated.Results show that:the proposed cohesion-weakening bounding surface model could reasonably capture the hardening-softening behavior of rock.The proposed constitutive model could accurately predict the stress distributions of the deep tunnel and could be used as a reference for the design of the support structure.The ground response curve(GRC)derived in this paper could reflect the response characteristics of the surrounding rock but provide slightly larger prediction on deformation on the middle of the GRC under same the supporting pressure value.The value of residual cohesion has a strong influence on the ground response curve.The conclusions of this paper could provide an effective reference for the development of support design and construction methods and the safety of deep tunnels.关键词
深部洞室/黏聚力/弱化/边界面理论/响应/围岩特征曲线Key words
deep tunnel/cohesion/weakening/bounding surface theory/response/ground response curve分类
交通工程引用本文复制引用
梁基冠,黄林冲,马建军,杨宏伟..基于黏聚力弱化边界面模型的深部洞室响应分析[J].铁道科学与工程学报,2024,21(6):2396-2405,10.基金项目
国家自然科学基金资助项目(51978677,52278422) （51978677,52278422）
基础科研项目(JCKY2020110C096) （JCKY2020110C096）
深圳市科创委可持续发展计划专项(KCXFZ202002011008532,KCXFZ20201221173207020) （KCXFZ202002011008532,KCXFZ20201221173207020）
