冲孔灌注桩桩孔纠偏预防技术研究及应用  

Correction and prevention of deviation in impact drilling of cast‑in‑place pile holes

作　　者：蒋凯 邓宇 孟宝华 秦峰焰 JIANG Kai;DENG Yu;MENG Baohua;QIN Fengyan(Chengdu Surveying Geotechnical Research Institute Co.,Ltd.of MCC,Chengdu Sichuan 610023,China)

机构地区：[1]中冶成都勘察研究总院有限公司,四川成都610023

出　　处：《钻探工程》2022年第1期153-159,共7页Drilling Engineering

摘　　要：冲孔灌注桩虽然在各类地层都具有广泛的适用性,但是在复杂地质条件下,极易发生偏孔。结合某高层建筑冲孔灌注桩施工中频繁偏孔的情况,对冲孔过程中的偏孔问题进行全面分析研究。以桩孔纠偏预防为目标,从应对孤石和斜硬岩层2个方面来针对性进行研究,应对孤石时,合理控制钻头、冲程及冲孔频率;应对斜硬岩层时,研究了钻头增厚硬质合金块改进技术。经现场应用,有效地避免了偏孔的产生。Although impact drilled cast‑in‑place piles have wide applicability in all kinds of strata,holes are prone to deviat under complex geological conditions.In view of frequent deviation of holes in the construction of impact drilled cast‑in‑place piles for a high‑rise building,hole deviation in the impact drilling process is comprehensively analyzed and studied.With hole deviation correction and prevention as the subject of study,research was carried out for two specific cases:deflection from solitary stones and dipped hard rock stratum.For solitary stones,the bit,impact stroke and frequency were properly controlled;for dipped hard rock stratum,increase of the thickness of the TC chips was studied for the bit.Field application demonstrated that hole deviation was effectively avoided.

关 键 词：冲孔灌注桩 孤石 斜硬岩层 偏孔 纠偏预防 

分 类 号：TU473.14[建筑科学—结构工程]