摘要
衬砌管片接头是隧道衬砌结构的薄弱部位,在隧道发生火灾时,容易产生变形、破坏,进而影响整体结构的稳定性及安全性。文章根据现有研究,归纳总结了混凝土和螺栓热工力学参数随温度变化的规律;通过COMSOL Multiphysics软件对3种不同形式的管片接头(直螺栓接头、弯螺栓接头和滑入式接头)的高温性能进行数值模拟。结果表明:(1)管片升温滞后于环境温度,距离受火面越远,温度变化越小,距受火面30 cm以上,管片温度不变化;(2)管片内侧温度升高引起混凝土膨胀导致管片向外张开,3种接头的张开量随时间和温度的变化规律一致,接头形式对管片最终张开量影响较小;(3)管片温度超过100℃后,接头塑性应变急剧增大,上升速率为:滑入式接头>直螺栓接头>弯螺栓接头;接头中螺栓变形破坏主要取决于管片接缝张开量和距受火面的距离,与接头形式没有关系。
Lining segment joints are weak parts of a tunnel’s lining structure,which are prone to deformation and damage in case of tunnel fire,thus affecting the overall stability and safety of the structure.This paper summarizes the changing patterns of the concrete and bolt thermal-mechanical parameters with temperature based on existing studies,conducts numerical simulations of the high-temperature performance of three segment joints(straight bolt joint,bent bolt joint and slide-in joint)through the COMSOL Multiphysics software,and draws the main conclusions as follows:(1)the warming of the segments lags behind the ambient temperature,where the farther they are away from the fire surface,the smaller the change in temperature will be,and when they are more than 30 cm from the fire surface,the segment temperature shows no change;(2)the expansion of the concrete caused by the increase in temperature of the inner side of the segments leads to the outward opening of the segments,and the changing pattern in the opening extent of the three joints with time and temperature is consistent,while the form of the joints has insignificant impact on the final opening extent of the segments;(3)once the temperature of the segments exceeds100℃,the plastic strain response of the joints increases sharply with the rising rates sequenced as slip-in joint>straight bolt joint>bent bolt joint;the deformation and damage of the bolts in the segment joints mainly depend on the extent of the joint opening and their distances from the fire surface but are not related to the form of the joints.
作者
舒禄山
薛亚东
SHU Lushan;XUE Yadong(Key Laboratory of Geotechnical and Subsurface Engineering of the Ministry of Education,College of Transportation Engineering,Tongji University,Shanghai 200092;College of Civil Engineering,Tongji University,Shanghai 200092)
出处
《现代隧道技术》
CSCD
北大核心
2021年第S01期64-72,共9页
Modern Tunnelling Technology
基金
国家自然科学基金(52078377)
关键词
衬砌结构
隧道火灾
多场耦合
管片接头
数值模拟
Lining structure
Tunnel fire
Multi-field coupling
Segment joint
Numerical simulation
