【摘要】 以港珠澳大桥主体工程为背景,采用两根钻孔灌注桩进行试桩实践,为获取设计参数,采用自平衡法进行成桩静载试验,且对该区深基础海上施工工艺进行了研究。研究结果表明:钻进中在覆盖层内采用四翼刮刀钻头,岩层内采用球齿滚刀钻头解决了海上桩基施工对设备性能要求高的难题;在实际成孔施工时,对桩号SZ5桩基采用海水+原状土造浆,对桩号SZ6桩基采用淡水+原状土造浆,研制的高质量泥浆保证了两桩钻孔效果良好;通过对静载试验数据的分析,综合考虑多种因素,获取了相关设计参数,完善了大桥桩基设计。以上研究成果可为大直径钻孔灌注桩的应用提供参考。更多还原

【Abstract】 Taking Hong Kong-Zhuhai-Macao Bridge as an engineering example, two bored piles are regarded as the test piles. The parameters are obtained based on self-balanced load test piles. The construction process of deep foundation of the sea is studied. The results verify that the problem of constructing offshore pile foundation with high requirements for equipment performance drilling is solved by using the four-wing drag bit in the cover layer and ball hob drill head in the rock layer. In the actual construction of the bore holes, for pile No. SZ5, seawater + undisturbed soil slurry are used, and for pile No. SZ6, the freshwater + undisturbed soil slurry are used. High-quality mud is developed to ensure the quality of the two bored piles. Through the analysis of the static load test data, comprehensive consideration of various factors, related design parameters are obtained so as to improve the pile foundation design. The results may provide reference for applying large-diameter bored piles.更多还原