摘要
为了探索隧道拱顶二次衬砌背后不同范围内存在空洞条件下高速列车气动荷载对隧道二次衬砌结构的影响,采用隧道空气动力学的流体力学分析方法及结构力学分析方法,对二次衬砌结构的受力进行研究。研究结果表明:在气动荷载作用下,隧道二次衬砌结构处于"拉—压"的循环受力状态中;在隧道拱顶二次衬砌背后存在空洞时,衬砌结构上产生的瞬态应力变化规律与其受到的气动荷载变化规律一致,当列车运行速度为350km·h-1时,二次衬砌结构上产生的最大瞬态应力是同一时刻气动荷载的约39倍;在最大正峰值气动荷载作用下,随着拱顶二次衬砌背后空洞范围的增大,拉应力范围逐渐变小,拉应力值先增大后减小;在最大负峰值气动荷载作用下,隧道拱顶二次衬砌第一主应力仅有压应力而无拉应力作用,而且随着拱顶二次衬砌背后空洞范围的增大,二次衬砌受压区的范围逐渐变小,压应力值先增大后减小;二次衬砌结构上产生的最大应力绝对值随着列车运行速度的提高而增大,且与列车运行速度的平方成二次函数关系。
In order to explore the influence of the aerodynamic load of high speed train on the secondary lining structure of tunnel within different ranges with cavities behind the secondary lining of tunnel vault,the fluid mechanics analysis method of tunnel aerodynamics together with structural mechanics analysis method were adopted to study the stress of secondary lining structure.Results show that the secondary lining structure is in the cyclic stress state of＂tension and compression＂under the action of aerodynamic load.When there are cavities behind the secondary lining of tunnel vault,the variation of transient stress produced on lining structure is consistent with that of the aerodynamic load.When the train speed is 350 km·h-1,the maximum transient stress produced on secondary lining structure is about 39 times as much as that of aerodynamic load at the same time.Under the maximum positive peak aerodynamic load,with the increase of the cavity range behind the secondary lining of tunnel vault,the range of tensile stress decreases gradually,and the tensile stress value increases first and then decreases.Under the maximum negative peak aerodynamic load,the first principal stress of secondary lining only has compressive stress without tensile stress.With the increase of the cavity range behind the secondary lining of tunnel vault,the range of compressive stress decreases gradually,and the compressive stress value increases first and then decreases.The absolute value of the maximum stress produced on secondary lining structure increases with the increase of train speed,and has a quadratic function relationship with the square of train speed.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2017年第6期56-62,共7页
China Railway Science
基金
国家自然科学基金资助项目(51678036)
关键词
高速铁路隧道
气动荷载
二次衬砌
结构应力
空洞
High speed railway tunnel
Aerodynamic load
Secondary lining
Structural stress
Cavity
