岩溶地质钢护筒跟进法桩基施工工艺

桩基作为一座桥梁的重要组成部分,桩基的施工质量决定了整座桥梁的总体质量,决定着桥梁的可使用年限。贵阳地区地质构造复杂,贵阳市区便处在一较大岩溶盆地。贵阳市轨道交通1号线7标段施工的下麦西1号双线大桥所处地质环境就是岩溶强发育地段,且地下岩层见溶率较高,因此对桩基施工提出了更高的要求。下麦西1号桥0-2#桩基施工时就是采用钢护筒跟进法来处理较大溶洞的,事实证明钢护筒跟进法处理高大溶洞是保证质量和安全,缩短工期的一种稳妥可靠的施工方案。文章就是对岩溶地质处采用冲击钻成孔、钢护筒跟进法施工桩基的工艺予以阐述,希望对以后类似地质条件下桩基施工有所帮助。

Pile foundation is an important part of a bridge. The construction quality of pile foundation determines the overallquality of the whole bridge and the useful life of the bridge. Because the geological structure of Guiyang is complex, the urban areaof Guiyangis located in a large karst basin. The geological environment of Xiamaixi No.1 double-line bridge under construction of No.7 section of Guiyang Rail Transit Line 1 is in the area of strong karst development, and the dissolution rate of underground rock isrelatively high, so the higher requirements for pile foundation construction are put forward. In the #0-2 pile foundation construction ofXiamaixi No.1 Bridge, the steel casing tube follow-up method is used to deal with the large karst cave. It has been proved that thesteel retaining tube follow-up method is a safe and reliable construction scheme to ensure the quality and safety and to shorten theconstruction period. This paper expounds the construction technology of pile foundation in karst geology by means of percussivedrilling and steel casing tube follow-up method, hoping to be helpful to pile foundation construction under similar geological condi-tions in the future.