富水黄土、泥岩隧道塌陷段施工技术

Construction Techniques for the Collapsing Sections of a Tunnel in the Rich-Watered Yellow-Earth and Mudstone Stratum

富水黄土、泥岩分层隧道塌陷段由于受拱部黄土易失稳、坍塌影响,施工开挖极为困难。阐述了在通过地质雷达有效超前预报的情况下,采用密集超前管棚和临时拱架形成悬托结构能有效抑制隧道拱部富水黄土塌陷,施工中合理预留核心土尺寸和掘进进尺,配合监控量测数据,仰拱及时闭合,做好临时排水能有效解决此类地质情况下隧道施工难题。

The collapsing section of a tunnel in the rich-watered yellow earth and mudstone stratum is very difficult to excavate because of the instability of the yellow earth of the arch body,and the excavation construction is often affected by collapsing.However,with the geological radar used to perform the effective forecast,densely-provided extra-advanced tube-shed and temporary arch racks are combined to form a boom structure to effectively prevent the rich-watered yellow earth at the arch body of the tunnel from collapsing.In the course of the construction,the rational-sized core earth is pre-left,the progress of the digging is strictly controlled.With great and timely attention paid to the survey and monitoring data,the inverted arch made to close in time,and a good job done of the temporary draining,all the technical difficulties in the construction of a tunnel in similar kinds of geological conditions can be effectively overcome.