嵌岩旋挖钻孔钢管柱桩施工质量控制要点

钢管柱作为逆作法施工时的竖向承重结构,基础通常采用钻孔灌注桩,钢管柱底端嵌入桩身混凝土中,形成一柱一桩的结构体系。该体系能承受较大的竖向荷载,对桩基的承载力、垂直度和沉降要求严格。通过工程实例,针对复杂地质条件下大直径嵌岩旋挖钻孔钢管柱桩施工过程中易发生的孔壁坍塌、钻孔偏斜、孔底沉渣厚度、混凝土标高等质量问题,进行了原因分析,并提出了相应的预防和解决措施,取得了良好的效果,确保了钢管柱桩的施工质量,其经验可供类似工程参考。

Quality Control Points of Rock-socket Revolving Digging Bored Steel Pipe Columns Construction

The steel pipe column is the vertical load-bearing structure of top-down method, bored grouting pile is often used as its foundation. The bottom ends of the steel pipe piles were embedded in pile concrete to form the structural system with one column on one pile. Because of the vertical loads on this structural system, the requirements on the bearing capacity, verticality and settlement of the pile foundation are very strict. According to the problems of large diameter rock-socket revolving digging bored steel pipe columns construction under complicated geological conditions, this paper analyzes the different causes by examples and proposes prevention measures to ensure construction quality, which can be reference to similar project.