紧邻地铁站深基坑地质钻引孔钢花管低压注浆土体加固技术

Low Pressure Grouting Soil Reinforcement Technology Using Steel Flower Pipes for Geological Drilling Guiding Hole of Deep Foundation Pits Adjacent to Subway Station

以昆明市惠悦城紧邻地铁站基坑工程为例,采用对原状土扰动较小的地质钻机钻进引孔,钻孔完成后,将制作好的钢花管插入钻孔中,孔口用注浆专用封孔阀封堵,封堵完成后进行低压注浆,注浆后水泥浆通过自流扩散到土质比较疏松的杂填土层,使原来土质较差、疏松的土体固结,提高原状土体的强度及稳定性,从而减少基坑开挖过程中的变形对周边环境的影响,为地质钻引孔钢花管低压注浆土体加固施工技术在基坑邻近建(构)筑物区域的推广应用提供可借鉴的经验。

Taking the foundation pit project adjacent to the subway station in Huiyue City,Kunming City as an example,the guiding hole is drilled with a geological drill with less disturbance to the undisturbed soil;after the drilling is completed,the made steel flower pipes are inserted into the dilling hole,and the hole opening is sealed with a dedicated grouting sealing valve;after the sealing is completed,low-pressure grouting is carried out.After grouting,the concrete slurry diffuses through self-flow to the loose soil layer,causing the previously poor and loose soil to solidify.The strength and stability of the undisturbed soil are improved,and the impact of deformation during excavation on the surrounding environment is reduced.It provides valuable experience for the promotion and application of low pressure grouting soil reinforcement construction technology for geological drilling and steel flower pipe in the vicinity of buildings(structures)in the foundation pit area.