摘要
顺层是隧道洞口常见的不良地质,在受到降水或施工扰动的影响下常发生滑塌等地质灾害。依托叙毕铁路张家沟隧道,对隧道洞口顺层滑坡开展研究,通过调研分析,提出了张家沟隧道洞口滑坡后的处置措施,并结合数值模拟方法对处置措施进行验证。结果表明:(1)顺层由于岩层走向与隧道轴向夹角较小,岩层之间的结合力较小,在受到降水或施工扰动时易发生滑坍事故;(2)对于洞口段滑坡后的处置措施,常先采用直接加固与间接加固相结合的措施保障坡面的稳定性,再采取合理的方式进洞;(3)根据张家沟隧道出口段的顺层滑坡特征,采取锚索框架梁对坡面进行防护,并在洞口段增设明洞,对仰坡采取桩基托梁挡墙进行支护的措施。通过数值模拟的验证,表明该措施能够较好地保障边仰坡的稳定与隧道结构的安全。
Bedding is a common unfavorable geological condition at the tunnel portal,and geological disasters such as landslide often occur under the influence of precipitation or construction disturbance.In this study,based on the Zhangjiagou Tunnel on the Xuyong-Bijie Railway,the bedding landslide at the tunnel portal is studied.Through survey analysis,treatment measures after the landslide at the Zhangjiagou Tunnel portal are proposed,and these measures are verified with the numerical simulation method.Result indicate that:(1)due to the small angle between the strike of the rock stratum and the axial direction of the tunnel,the binding force between rock strata is relatively small,and landslide and collapse accidents are prone to occur when disturbed by precipitation or construction;(2)For treatment measures after the landslide at the tunnel portal,a combination of direct reinforcement and indirect reinforcement is often firstly used to ensure the stability of the slope surface,and then a reasonable approach is taken to access the tunnel;(3)According to the characteristics of the bedding landslide in the section of the Zhangjiagou Tunnel portal,anchor cables and frame beams are used to protect the slope surface,and an open cut tunnel is added at the tunnel portal section.Pile foundation supporting beams and retaining walls are used to support the front slope.The verification by numerical simulation shows that these measures are allowed to effectively guarantee the stability of the slope and the safety of the tunnel structure.
作者
雷龙
廖雄
LEI Long;LIAO Xiong(China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031)
出处
《现代隧道技术》
CSCD
北大核心
2023年第S01期168-173,共6页
Modern Tunnelling Technology
关键词
隧道洞口
顺层
滑坡
进洞措施
Tunnel portal
Bedding
Landslide
Measures for accessing the tunnel
