小三峡隧道D1K671+670处巨型溶洞处理措施研究

Research on Treatment Measures for Giant Karst Cave at D1K671+670 of Xiaosanxia Tunnel

文章基于郑万高铁重庆段小三峡隧道D1K671+670处隧底大型溶洞发育特征和工程补勘资料,从施工难度、运营风险、工程投资等方面进行对比分析,最终确定箱梁桥方案跨越溶洞的处理方案。通过结构计算与工程类比进行隧道桩基托梁结构设计,隧道拱顶空腔采取护拱+缓冲层方案,地表河道采用混凝土进行铺砌。工程实践表明,该处大型溶洞的综合处理措施取得了很好的效果,可供类似工程借鉴参考。

Based on the development characteristics of giant karst cave at the bottom of D1K671+670 of Xiaosanxia Tunnel in Chongqing section on Zhengzhou-Wanzhou High-speed Railway and the engineering supplementary survey data,this paper makes a comparative analysis from the aspects of construction difficulty,operation risk and engineering investment,and finally determines the treatment scheme for box girder bridge crossing the karst cave.Through structural calculation and engineering analogy,the structure design of tunnel pile foundation joist is carried out.The tunnel vault cavity adopts the arch protection+buffer layer scheme,and the surface river channel is paved with concrete.The engineering practice shows that the comprehensive treatment measures for the giant karst cave have achieved good results,which can be used as reference for similar engineering.