缓倾层状岩体隧道底部结构变形和裂缝发展规律  

Deformation and Crack Development Laws of Bottom Structure ofGently Inclined Layered Rock Mass Tunnel

作　　者：刘一炜 陈彬科 张志强[1,2] LIU Yiwei;CHEN Binke;ZHANG Zhiqiang(Key Laboratory of Transportation Tunnel Engineering,Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]西南交通大学交通隧道工程教育部重点实验室,成都610031 [2]西南交通大学土木工程学院,成都610031

出　　处：《铁道建筑》2023年第7期104-108,共5页Railway Engineering

基　　金：国家自然科学基金高铁联合基金(U1934213)。

摘　　要：以渝黔铁路(重庆—贵阳)老周岩隧道为工程背景,采用三维离散元数值模拟方法,分别研究了不同岩层层理倾角和侧压力系数条件下隧道底部结构变形特征和裂缝发展规律。结果表明:隧道底部结构隆起量和中轴线两侧隆起不对称程度均随倾角、侧压力系数的增大而增大,底部结构隆起量最大值出现在层理方向与隧道底部相切位置;底部结构裂缝张开量、剪切滑移量和分布范围均随倾角、侧压力系数的增大而增大;随倾角增大裂缝发展最显著位置由仰拱中心向右墙脚移动,随侧压力系数增大裂缝向深部扩展程度增大,底部结构三角形破裂区域范围也逐渐增大。Taking the Laozhouyan Tunnel of the Chongqing-Guiyang Railway as the engineering background,a threedimensional discrete element numerical simulation method was used to study the deformation characteristics and crack development laws of the tunnel bottom structure under different rock inclined angles and lateral pressure coefficients.The results show that the amount of uplift at the bottom of the tunnel and the degree of asymmetry on both sides of the central axis increase with the increase of inclined angle and lateral pressure coefficient.The maximum amount of uplift at the bottom of the tunnel occurs at the position where the bedding direction is tangent to the bottom of the tunnel.The opening amount,shear slip amount,and distribution range of cracks in the bottom structure increase with the increase of inclined angle and lateral pressure coefficient.As the inclined angle increases,the most significant position for crack development moves from the center of the inverted arch to the right foot of the wall.As the lateral pressure coefficient increases,the degree of crack propagation towards the deep increases and the triangular fracture area range of the bottom structure gradually increases.

关 键 词：铁道隧道 变形规律 数值模拟 缓倾层状岩体 黏合块体模型 倾角 侧压力系数 

分 类 号：U459.1[建筑科学—桥梁与隧道工程]