(嘉兴学院建筑工程学院 314001) 高 飞(上海岩土工程勘察设计研究院 200002)
【提要】 桩端后注浆是软土地区大直径超长钻孔灌注桩发展的必然趋势。依据软土地区某超高层建筑大直径超长钻孔灌注桩试桩的竖向抗压静载试验结果，通过对基桩的竖向极限承载力性状、桩身轴力传递特性以及桩侧阻力、桩端阻力发挥特性的分析研究，揭示了桩端后注浆对基桩承载性状的影响情况，深入探讨了软土地区大直径超长后注浆灌注桩的荷载传递机理和竖向承载性状，并提出了单桩承载力的估算方法。
【关键词】软土 大直径超长灌注桩 桩端注浆 高吨位静载试验 荷载传递
Test Research   on Vertical Bearing Capacity of Superlong Largediameter Basegrouting Bored Piles in Soft Soil/Shen Xiaomei1,Gao Fei2(1 Architecture Engineering College, Jiaxing University,Jiaxing 314001,China;2 Shanghai Geotechnical Investigation & Design Institute,Shanghai 200002,China)
Abstract:Basegrouting is an inevitable development trend of overlength largediameter bored piles in soft clay area.Based on the results of vertical static loading test of the two single piles with basegrouting in the super highrise building,the influence of basegrouting on the bearing property of the pile is revealed by analyzing its properties of vertical limit bearing capacity,axial load transmission and tip and shaft resistance of pile.The load  t-ransfer performance and bearing mechanism are discussed in detail.A method is suggested to estimate the ultimate bearing capacity of a single pile.
Keywords:soft soil;super long and large diameter bored pile;base grouting;vertical static loading test