不同埋深铁路隧道仰拱受力特征研究

以董志塬区银西高铁黄土隧道为例,对不同埋深条件下隧道仰拱的基底接触压力和钢拱架应力随时间的变化规律、空间分布特征及其差异性进行了对比研究.研究结果表明,浅埋隧道基底接触压力变化时间较深埋隧道略长;不同埋深隧道仰拱处最小基底接触压力均出现在拱底中心处,最大基底接触压力均出现在拱脚处,且同一部位浅埋隧道基底接触压力明显大于...

Research on Stress Characteristics of Inverted Arch of Railway Tunnel in Different Buried Depth

Taking the tunnels across loess areas in the Dongzhiyuan area of Yinchuan-Xian Highspeed Railway as example,the change rule of contact pressure beneath foundation and the stress of steel arch with time,the spatial distribution characteristics and their differences under the conditions of different buried depth are studied.The results show that the change time of contact pressure beneath foundation of shallow tunnel is slightly longer than that of deep tunnel;the minimum contact pressure beneath foundation appears at the center of the arch bottom,and the maximum contact pressure beneath foundation appears at the arch foot,moreover,the contact pressure beneath foundation of the shallow-buried tunnel in the same location is obviously greater than that of the deep-buried tunnel;in the same position of inverted arch,the stress of steel arch in deep-buried tunnel is obviously larger than that of in shallow-buried tunnel;the steel arch at the inverted arch mainly bears the compressive stress,the steel arch at the bottom of shallow-buried tunnel has the highest compressive stress,which can reach about 12 MPa,and the steel arch foot of deep-buried tunnel has the highest compressive stress,which can reach 26~33 MPa.The study results can provide reference for the design optimization and construction of loess tunnel invert.