摘要
应用有限差分软件FLAC3D分析了隧道断面形状、围岩类别、入射波方向及地震加速度水平四类因素对隧道地震响应的影响。综合考虑围岩位移、塑性区范围、应力场分布、剪应变增量等指标,得出圆形及改进直墙拱形等光滑过渡的断面形式对隧道抗震稳定性较为有利;随着围岩强度的降低及破碎程度的增加,隧道在地震响应作用下将越来越不稳定;横向地震波主要影响隧道在地震荷载下最不利的受力位置,竖直向地震波则引起围岩中应力的增大等。
With the application of the finite-difference program FLAC3D,the four factors of the impacts on the seismic responses of tunnel,i.e.the section shape,category of surrounding rock,direction of incident wave and seismic acceleration,are analyzed herein.Under the comprehensive consideration of the indexes of the displacement,area of plastic zone,stress field distribution and shear strain increment of the surrounding rock,it is known that the smooth-transition section shapes such as circular wall,modified straight wall,etc.are favorable to the seismic stability of tunnel.Along with the decrease of the strength and increase of the broken grade of the surrounding rock,the tunnel is to be more and more unstable ; for which the transverse seismic wave is mainly to impact the most unfavorable stress position of the tunnel,while the vertical seismic wave is to cause the increase of the stress in the surrounding rock of the tunnel.
出处
《水利水电技术》
CSCD
北大核心
2014年第1期60-64,68,共6页
Water Resources and Hydropower Engineering
关键词
隧道
地震响应
影响因素
地震加速度
tunnel
seismic responses
influencing factor
seismic acceleration
