研究桩基的深度效应是为了得到较好的技术和经济指标。扩底桩一直被视为大直径桩进行研究,然而,由于有扩大头,扩底桩的受力变形性能、破坏状态与普通大直径桩既有相同点又存在较大差异,参照大直径桩方法研究扩底桩深度效应不适合。研究扩底桩的深度效应,应针对扩底桩的特点,考虑桩长对端阻力发挥的影响。本文采用数值方法分析桩长对扩底桩技术经济指标的影响,统计合肥地区95根扩底桩试验数据,分析统计结果,得到端阻力分配比例与桩长的关系,提出扩底桩临界设计桩长建议值,最后通过一组扩底桩试验数据验证该建议值的有效性。
Abstract
The purpose to study the depth effect of the pile is to get appropriate technical and economic indicators. The belled pile has always been considered as a large diameter pile, but the deformation behavior and failure state of belled piles are similar to and different from those of equal diameter piles,because of their enlarged tip. The method to study the depth effect was suitable for large diameter pile, but not for belled pile. Based on the characteristics of belled pile, the depth effect was studied with considering the influence of pile length to the end resistance. In this paper the influence of pile length on technical and economic indexes of belled pile with the numerical method was analyzed, and a total of 95 large-diameter belled pile tests in area of Hefei city were studied. The statistical results were analyzed, the relationship of the end resistance distribution proportion and the pile length was obtained, and the suggested value of critical design length of belled pile was proposed in the paper. Finally, the suggested value for the length of belled pile will be further verified independently with the results of a group of additional belled pile tests.
关键词
扩底桩 /
大直径桩 /
深度效应 /
临界桩长
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Key words
belled pile /
large-diameter pile /
effect of depth /
critical pile length
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中图分类号：
TU473
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参考文献
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