上海地区超长后注浆钻孔桩竖向承载力试验研究

桩端注浆是上海地区大直径超长灌注桩发展的必然趋势。依据上海地区某超高层商业建筑试桩的高吨位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,揭示了桩底注浆对基桩承载性状的影响情况,深入探讨了上海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。

Experimental study on vertical bearing capacity of post cast bored pile in Shanghai region

Casting from pile end is an inexorable developmental trend of large diameter ultra-long cast filling pile in Shanghai region. According to the experimental result of high load vertical compression static bearing resistance of test pile of a commercial ultra-high rise building in Shanghai region, this paper found the influence of casting from the pile end on the state of foundation pile bearing capacity, thoroughly explored the principle of load transmission and vertical bearing state in ultra-long post cast filling pile in Shanghai soft soil region, and proposed the method of estimation for single pile beating capacity through the analytic study on the state of vertical limit beating capacity of foundation pile, transmission character of axial force in pile and resistance effect on pile side and end.