极密实粉细砂层大直径钢管桩桩基参数分析

现行桩基规范缺少极密实粉细砂层桩端阻力和桩侧阻力的规定。结合某海港工程钢管桩基静载及高应变检测,探讨大直径钢管桩在极密实粉细砂层中的桩侧阻力和桩端阻力。高应变检测结果显示,极密实粉细砂层单位面积桩侧阻力范围为93～120. 01 k Pa,平均值为106. 6 kPa,1 500 mm钢管桩桩端阻力范围6. 742～6. 845 MN,平均值6. 780 MN。针对国内外规范对桩基承载力的估算计算结果进行分析,建议极密实粉细砂层桩侧阻力值取90～120 kPa,桩端阻力值取8～12 MPa。

Analysis of parameters of large-diameter steel-pipe piled foundations in very dense fine sand

The current pile foundation specification lacks the specification of the pile foundation parameters of very dense fine sand layers.This paper discusses the pile side of large-diameter steel-pipe piles in very dense fine sand layers in combination with the static load and high-strain testing of a steel pipe pile foundation in a harbor project.According to the results of high-strain testing,we know that the pile shaft-resistance range per unit area of the fine sand layer of this project is 93~120.01 kPa,and the average value is 106.6 kPa,and the tip-resistance range of 1 500 mm steel-pipe piles is 6.742~6.845 MN,and the average is 6.780 MN.After analyzing the calculation results of the bearing capacity of the pile foundation,it is recommended that the pile shaft-resistance value of the extremely dense fine sand layer takes 90~120 kPa,and the tip-resistance value of the pile takes 8~12 MPa.