铁道标准设计2025，Vol.69Issue(4)：129-138,10.DOI:10.13238/j.issn.1004-2954.202305300007
非等压荷载作用下隧道塑性区与扰动应力场分布规律
Distribution Patterns of Plastic Zone and Disturbed Stress Field in Tunnels Under Unequal Pressure Loads
摘要
Abstract
To investigate the distribution patterns of the plastic zone and disturbed stress field in tunnels under unequal pressure load,the Dongmachang No.1 Tunnel of the Huali Expressway was selected as a case study.An implicit equation for the plastic zone radius of a circular tunnel under unequal pressure conditions was derived based on the HOEK-Brown strength criterion.The plastic zone radius was calculated using MATLAB,and numerical simulations were performed using FLAC3D finite difference software for comparative verification.A comprehensive analysis was conducted to evaluate the effects of various factors on the plastic zone and disturbed stress field.The results showed that the shape of the plastic zone was determined by the lateral pressure coefficient(λ),with the plastic zone always concentrated in the direction of lower in-situ stress.As λ increased from 0.5 to 1.7,the plastic zone contracted horizontally and expanded vertically,transitioning from a"gourd-like"shape to an elliptical shape.When λ equaled 1,the plastic zone became circular,but with further increases in λ,it became elliptical or gourd-shaped.The size of the plastic zone was positively correlated with tunnel radius(r0),disturbance parameter(D),and in-situ stress(P),while negatively correlated with the rock material constant(mi)and the Geological Strength Index(GSI).The distribution of disturbed stress field was significantly affected by λand P,but was.less affected by D,mi,and GSI,and was almost independent of r0.The peak value of tangential disturbed stress σz was concentrated at 2 to 3 times the tunnel diameter,corresponding to the plastic zone radius,with the peak stress at λ=0.5 being 36.72％higher than at λ=1.7.As the distance from the tunnel increased,the disturbed stress field gradually approached the initial stress field,becoming nearly identical beyond eight times the tunnel diameter.Theoretical calculations,numerical simulations,and field measurements align well,with a maximum deviation of less than 0.5m,verifying the accuracy and reliability of the implicit equation for the plastic zone boundary.关键词
隧道工程/非等压荷载/塑性区/扰动应力/数值模拟Key words
tunnel engineering/unequal pressure load/plastic zone/disturbed stress/numerical simulation分类
交通工程引用本文复制引用
聂金诚,杨文波,寇昊,何川,曾泽润,谭芝文..非等压荷载作用下隧道塑性区与扰动应力场分布规律[J].铁道标准设计,2025,69(4):129-138,10.基金项目
四川省科技计划项目(2022JDJQ0018) （2022JDJQ0018）
中国建筑股份有限公司科技研发计划项目(CSCEC-2021-Z-26) （CSCEC-2021-Z-26）
