钻孔灌注桩“旋挖+冲反”施工工艺特点及质量控制

Construction Technology of Rotary Excavating and Percussive Reverse Circulation Excavating for Bored Piles

某工程采用钢筋混凝土钻孔灌注桩基础,在灌注桩施工中采用"旋挖+冲反"施工工艺,即在钻孔灌注桩施工中先使用旋挖钻机钻进成孔,待钻孔至硬质岩层地层时改用冲击反循环钻机钻至设计深度。详细介绍了该工艺的原理、特点、施工工艺流程及质量控制。

Reinforced concrete bored pile is adopted in some project. During the pile construction, rotary drilling and percussion reverse circulation drilling were used, which means the rotary drilling rig is used to drill during the construction of bored pile, and after drilling to the hard rock strata, the percussion reverse circulation drill rig is used instead of rotary drilling rig to achieve the projected depth. This paper mainly introduced principle, characteristics, construction process and quality control measures of this technology.