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针对全充填岩溶地区冲孔灌注桩施工中存在的沉渣过厚、孔内坍塌与漏浆、卡钻、偏孔、和断桩等问题,基于全充填岩溶地区的特点,探讨了问题产生的原因、解决方案与预防措施,通过某工程桩基施工表明:依据地层特性选择相应的泥浆浓度与二次清孔落到实处是解决孔底沉渣过厚的有效措施;回填片石与黏土或钢护筒护壁能有效解决孔内坍塌与漏浆;将卡钻处的石块挤进孔壁或击碎,必要时可利用高压水枪冲击卡点处处理卡钻;可用回填与孔底岩石强度相同的块石或混凝土,再重新冲击钻进,必要时可采用爆破进行钻孔纠偏;导管的气密性与初次灌注的混凝土量是影响断桩的两个重要因素。
In view of the problems such as excessive sediment, collapse and leakage in the hole, stuck hole, partial hole and broken pile in the construction of perforated cast-in-place pile in the place of full filling karst, the causes of the problem are discussed based on the characteristics of the full fill karst area , Solutions and preventive measures through a project pile foundation construction shows that: according to the formation characteristics of the corresponding choice of mud concentration and secondary clear hole falls to the extent practical measures to solve the hole bottom sediment is too thick; backfilling tablets and clay or steel casing Wall can effectively solve the holes collapse and leakage of the mortar; stuck in the hole at the card hole drilling or crushing, if necessary, the use of high-pressure water jet impact card processing at the card point; available backfill and rock bottom hole with the same strength Stone or concrete, and then re-impact drilling, if necessary, can be used to rectify the borehole; duct tightness and initial perfusion of concrete is the impact of two important factors of broken pile.