特殊地质条件下钻孔灌注桩施工工艺对比研究与应用

Comparative Study and Application of Bored Pile Construction Technology under the Special Geological Condition

大桥桩基施工中碰到溶洞、斜面岩、地表塌陷等特殊情况,无法按传统的钻机正常施工,施工过程中出现偏离孔位,易造成偏位、卡钻、倾倒、塌孔、漏浆、掉钻等技术问题。本文以某工程D匝道桥起点桩号为例,对斜面岩桩基施工问题出现的原因进行了剖析,并采取了桩底浇筑高强度混凝土和分时间段回填石块等处理措施进行处理。将二种处理措施进行现场施工对比,桩底分时间段回填高强度石块处理措施成功地解决了斜面岩桩基施工技术问题,为以后斜面岩桩基钻孔施工提供了参考和借鉴。

The traditional drill cannot normal construction when encounter karst cave,slope rock,surface subsidence and other special circumstances in bridge pile foundation construct,it was easy cause deviation,sticking,dumping,the hole collapse,slurry leakage,drilling out etc. technical problems. This paper took project D ramp bridge starting point pile as an example,analyzed the cause of slope rock pile foundation construction,and took the treatment measures such as the high strength concrete and the time section were adopted to deal with the problems. To compare two treatment measures for construction site contrast,slope rock pile foundation construction technical problems were solved successfully by backfill high strength rocks points in time in pile bottom,which provided reference and promotion for slope rock pile foundation drilling construction.