强震区隧道洞口段新型墙-板抗减震措施的效果分析

Analysis of the Effectiveness of Novel Wall-Panel Anti-seismic Measures for Tunnel Portal Segments in Seismic Areas

为了进一步提高强震区铁路隧道的安全以及抗震性能,依托包银铁路甘德尔山隧道,运用数值模拟软件FLAC 3D,针对强震区隧道洞口段墙-板和墙-板-减震层的抗减震作用效果进行研究。研究结果表明,与不采用抗减震措施相比较,采取墙-板抗震措施后,横向位移减小了5.95%,竖向位移减小了45.87%,最小安全系数增大了40.91%~49.25%,最大主应力的抗震作用效果达到了63.56%,最小主应力的抗震作用效果为4.04%,最大剪应力抗震作用效果为8.35%;采取墙-板-减震层减震措施后,横向位移减小了13.11%,竖向位移减小了43.88%,最小安全系数增大了65.82%~74.50%,最大主应力的减震作用效果达到了75.11%,最小主应力的减震作用效果为10.21%,最大剪应力减震作用效果为12.80%。采用墙-板-减震层的抗减震措施优于墙-板结构。推荐采用墙-板-减震层措施对甘德尔山隧道进行抗减震加固设计。

In order to further improve the safety and seismic resistance of railway tunnels in meizoseismal areas,this study takes the Gandeer Mountain Tunnel on the Bao-Yin railway as the research object,and applies the numerical simulation software FLAC 3D to study the anti-seismic effect of wall-panel and wall-panel-damping layer in tunnel portal segment.The research results show that,compared with the case without anti-seismic measures,the horizontal displacement is reduced by 5.95%,the vertical displacement is reduced by 45.87%,the minimum safety factor value is increased by 40.91%~49.25%,the seismic effect on the maximum principal stress is 63.56%,the seismic effect on the minimum principal stress is 4.04%,and the seismic effect on the maximum shear stress is 8.35%.After taking the anti-seismic measures of wall-panel-damping layer,the horizontal displacement is reduced by 13.11%,the vertical displacement is reduced by 43.88%,the minimum safety factor value is increased by 65.82%~74.50%,the seismic effect on the maximum principal stress is 75.11%,the seismic effect on the minimum principal stress is 10.21%,and the seismic effect on the maximum shear stress is 12.80%.The anti-seismic measures of wall-panel-damping layer are superior to those of wall-panel structure.It is recommended to use the wall-panel-damping layer measures to reinforce and strengthen the Gandeer Mountain Tunnel against seismic hazards.