交通荷载下断层破碎带隧道支护结构动力响应特性研究

Study on Dynamic Response Characteristics of Tunnel Support Structure in Fault Fracture Zone Under Traffic Load

隧道受到车辆循环反复荷载作用,其工作性能受到不可忽略的影响,特别是穿越断层破碎带等不良地质处。以交通荷载作用下穿越断层破碎带的隧道为研究对象,通过数值模拟研究交通荷载作用下隧道变形沉降特征与支护结构受力特征。结果表明:(1)隧道沉降沿纵向长度先增大后减小,隧道纵深100 m即靠近断层破碎带处沉降最大;(2)隧道拱顶和仰拱处竖向沉降随交通荷载大小的增大而增大,随交通荷载频率的增大而减小;(3)隧道拱顶、仰拱的竖直应力峰值受交通荷载大小和频率的影响较大。

The working performance of the tunnel under the cyclic loading of vehicles can not be ignored,especially when it crosses the fault fracture zone and other unfavorable geological places. This paper takes the tunnel crossing the fault fracture zone under traffic load as the research object, and studies the deformation and settlement characteristics of tunnel and the stress characteristics of supporting structure under traffic load through numerical simulation. The results show that:(1) the tunnel settlement increases first and then decreases along the longitudinal length, and the settlement reaches the maximum when the tunnel is close to the fault fracture zone at 100 m depth.(2) The vertical settlement of the tunnel arch and invert increases with the increase of peak traffic load, and decreases with the increase of traffic load frequency;(3) The peak vertical stress of tunnel arch crown and invert is greatly affected by the size and frequency of traffic load,while the peak vertical stress of arch waist is less affected.