综合管廊燃气爆炸对下穿隧道结构安全性的影响研究  

Influence of gas explosion in a utility tunnel on the structural safety of a undercrossing tunnel

作　　者：王岱 陈昌昊 张海 刘中宪 孟思博 WANG Dai;CHEN Changhao;ZHANG Hai;LIU Zhongxian;MENG Sibo(Joint Research Centre for Protective Infrastructure Technology and Environmental Green Bioprocess,School of Civil Engineering,Tianjin Chengjian University,Tianjin 300384,China;Tianjin Key Laboratory of Civil Structure Protection and Reinforcement,Tianjin 300384,China)

机构地区：[1]天津城建大学土木工程学院基础设施防护和环境绿色生物技术国际联合研究中心,天津300384 [2]天津市土木建筑结构防护与加固重点实验室,天津300384

出　　处：《振动与冲击》2023年第8期160-166,185,共8页Journal of Vibration and Shock

基　　金：国家重点研发计划项目(2017YFC0805000);国家自然科学基金(51878434,51908401);天津市科技计划项目(19PTZWHZ00080)。

摘　　要：针对综合管廊燃气爆炸时下穿隧道可能遭受破坏的风险,首先通过野外管廊燃气爆炸试验确定综合管廊超压时程,而后建立综合管廊-土体-下穿隧道整体三维有限元模型,并在综合管廊燃气舱内壁施加荷载,计算分析了下穿隧道的动力响应规律。结果表明:野外管廊燃气爆炸试验实测超压峰值高达0.63 MPa,且升压和降压持续时间均为0.1 s左右;隧道衬砌拱顶区域最先受到冲击,衬砌位移随时间的增大而增大,而衬砌应力则在超压峰值时刻达到最大,且隧道平行下穿时的衬砌应力超过正交下穿时的3.5倍;随着隧道和管廊间距的增大,隧道动力响应如衬砌应力、振动速度等均逐渐减小,且隧道正交下穿管廊时的减小趋势更明显;综合考虑各因素的影响,建议优先考虑隧道正交下穿综合管廊,且隧道与管廊的安全距离控制在7 m以上。研究结果可为综合管廊抗爆及下穿隧道工程设计等提供参考。For the possible damage risk of a tunnel passing through an underground utility tunnel under the gas explosion,firstly,the overpressure time history of the utility tunnel was determined through the field gas explosion test of the underground utility tunnel,then an overall three-dimensional finite element model of the utility tunnel,soil,and undercrossing tunnel was established,and the load was applied to the inner wall of gas tank of the utility tunnel to calculate and analyze the dynamic response law of the undercrossing tunnel.Results show that the measured peak overpressure of gas explosion is as high as 0.63 MPa,and the duration of overpressure at both rising stage and descending stage is about 0.1 s;the vault area of tunnel lining is impacted first,and the lining displacement increases with time,while the lining stress reaches the maximum at the peak of overpressure.The Mises stress of the parallel undercrossing tunnel can be more than 3.5 times than that of orthogonal undercrossing;with the increase of the distance between the tunnel and the utility tunnel,the dynamic response of the tunnel,such as lining stress and vibration speed,decreases gradually,and the decreasing trend is more obvious for the case of orthogonal undercrossing.Comprehensively considering the influence of various factors,it is suggested that the orthogonal undercrossing tunnel should be considered preferentially,and the safe spacing for the undercrossing tunnel should be greater than 7 m.The results can provide some reference for the anti-explosion design of utility the tunnel and the engineering design of the undercrossing tunnel.

关 键 词：野外试验 数值模拟 综合管廊 燃气爆炸 下穿隧道 动力响应 

分 类 号：TU375[建筑科学—结构工程]