充填黏土型岩溶隧道隧底加固技术研究

Research on Reinforcement Technology for Tunnel Bottom of Karst Tunnel Filled with Clay

以安六高速大用隧道隧底加固为背景,介绍了该工程DK38+290~DK38+330段的岩溶处理技术,提供了一种隧底加固技术。本工程的难点在于大型全充填溶洞下方存在的串珠状溶洞,在实际施工中,先用袖阀管对下方的串珠状溶洞进行加固,再用旋喷桩对隧道底板的大型全充填溶洞进行加固。工程实践证明:采取的隧底加固技术有效解决了隧道下方溶洞不稳定的问题,施工过程中的安全得以保障。

Taking the tunnel bottom reinforcement of the large-scale tunnel of anAnshun-Liupanshui expressway as the background,the karst treatment technology of the DK38+290~DK38+330 section of the project is introduced,and a kind of tunnel bottom reinforcement technology is offered.The difficulty of this project lies in the beaded karst cave under the large-scale fully filled karst cave.In actual construction,the beaded karst cave below is first reinforced with sleeve valve tube,and then the large-scale fully filled karst cave on the tunnel floor is reinforced with rotary jet grouting pile.The engineering practice has proved that,the adopted tunnel bottom reinforcement technology has effectively solved the problem of instability of the karst cave under the tunnel,and the safety in the construction process can be guaranteed.