摘要
为量化轴重与基底脱空对重载铁路硬岩隧道动力响应的影响,基于Hertz非线性轮轨接触理论,运用有限元软件建立列车-轨道-隧道-围岩一体化数值仿真模型,以此分析脱空状态下重载铁路硬岩隧道铺底结构动力响应特性及潜在不利部位。研究结果表明:在围岩压力和轴重30 t列车共同作用下,基底脱空时轨下铺底结构第1主应变最大动幅值为82.28×10^(-6),比无空洞时增大87.26%。轨下和侧沟处铺底结构是硬岩隧道的2个主要易损部位,由列车动载引起底部结构产生的动力响应最大幅值位于轨道正下方处,而由围岩压力引起底部结构的静态应变最大值位于侧沟下方,硬岩隧道轨下处动力响应更大且结构更薄弱,轨道正下方处铺底结构发生基底病害的可能性比软岩隧道更高,而软岩隧道中基底病害则更易在侧沟处产生。轴重每增大1 t,有空洞、无空洞条件下铺底结构第1主应变动幅值分别增加约2.56×10^(-6)和1.41×10^(-6)。基底空洞对隧道结构十分不利,不仅大幅提高了硬岩隧道底部结构动力响应幅值,还增大了围岩静载作用下底部结构静态应变值。空洞宽度每增大10 cm,轨下处铺底结构第1主应变动幅值约增大12.18×10^(-6),静态应变值约增大3.71×10^(-6)。但当空洞宽度超过50 cm时,其增长速度会下降。研究成果可为重载铁路轴重提升、降低隧道基底病害概率提供参考依据。
In order to quantify the influence of the train axle load and base cavity on the dynamic responses heavy haul railway tunnel,a train-tunnel-surrounding rock numerical model was established by using ABAQUS and Hertz nonlinear wheel-rail contact theory to analyze the dynamic response characteristics of a heavy-haul railway tunnel with base cavity in hard rock,and to determine its potential vulnerable positions.The results suggested that under the action of surrounding rock pressure and 30 t trainaxle load,the maximum principal strain’s amplitude of the bottom structure with cavity was 82.28×10^(-6),87.26%higher than that without considering the base cavity.The lower part of the side drain and rail were the two main vulnerable positions in the tunnel bottom structure,because the tunnel’s maximum dynamic responses caused by train load is located below the rail,while the maximum static value caused by surrounding rock pressure is located below the side drain.Hard rock tunnel has a higher dynamic responses and thinner structure under the rail,so the possibility of base disease under the rail may be higher in hard rock tunnel,while the base disease is more likely to occur at the side drain in soft rock tunnel.When the axle load increased by 1 t,with or without cavity,the amplitude of the maximum principal strain in bottom structure increased by 2.56×10^(-6) and 1.41×10^(-6),respectively.The dynamic amplitude and static strain of tunnel bottom structures are both greatly increased by the base cavity,which is very unfavorable to the tunnel bottom structure.When the cavity width increased by 10 cm,the amplitude of the maximum principal strain of the bottom structure under the rail increased by about 12.18×10^(-6),and the static value increased by 3.71×10^(-6).However,when the width of the cavity exceeds 50 cm,its growth rate decreases.It is expected to provide a reference for heavy haul railway to improve the axle load and reduce the probability of tunnel’s base disease.
作者
刘聪
龚志彪
沙珉
吴波
曾佳佳
朱若男
LIU Cong;GONG Zhibiao;SHA Min;WU Bo;ZENG Jiajia;ZHU Ruonan(School of Civil and Architectural Engineering,East China University of Technology,Nanchang 330013,China;Geological Survey of Jiangxi Province,Nanchang 330001,China;Jiangxi Nonferrous Geo-Minerals Exploration and Development Institute,Nanchang 330030,China)
出处
《铁道科学与工程学报》
EI
CAS
CSCD
北大核心
2023年第12期4667-4677,共11页
Journal of Railway Science and Engineering
基金
国家自然科学基金资助项目(52168055)
中国博士后科学基金资助项目(2022M711429)
江西省自然科学基金资助项目(20212ACB204001,20224BAB204058)
江西省地质环境与地下空间工程研究中心开放基金资助项目(GEUSJXDHJJ2022-009)
江西省教育厅科技项目(GJJ210704)。
关键词
重载铁路隧道
基底脱空
动力响应
底部结构
heavy haul railway tunnel
base cavity
dynamic response
bottom structure
作者简介
通信作者:吴波(1971-),男,四川阆中人,教授,博士,从事隧道与地下工程专业的教学与科研工作,E-mail:wubo@ecut.edu.cn。
