钻孔灌注桩是市区密集建筑处建造高层建筑的地基基础加强的较好方法,它噪音低、无振动、无挤压、无污染空气等,在国内外一些先进地区早已推广应用,我国亦于80年制订了灌注桩基础设计与施工规程JGJ4—80,国内灌注桩的孔径已超过1米,单桩极限承载力已逾千吨,但先决条件 Drilled cast-in-place piles are a better way to strengthen the foundation of high-rise buildings in urban dense buildings. They have low noise, no vibration, no extrusion, and no pollution. They have been widely used in advanced areas at home and abroad. In 1980, the design and construction rules for the foundation of cast-in-place piles were formulated. The bore diameter of domestic bored piles has exceeded 1 meter, and the ultimate bearing capacity of single piles has exceeded 1,000 tons, but the prerequisites