（东洋工程（上海）有限公司，上海200122）

[摘要]  从压桩力出发，对软土地区的压桩力公式进行了深入研究。发现单桩竖向极限承载力试验值通常比理论计算值提高较多，考虑时间效应下将会给基础结构设计带来较大的经济效益。通过拟合回归分析，获得了考虑时间效应下单桩承载力的预测公式，实现了对任意时刻单桩承载力的预测。经试验验证，该公式预测值与试验值误差较小，可在工程实践中参考使用。预测计算及试验结果均表明，单桩的最终极限承载力随休止时间的延长而增大，前期增长较快，后期较为缓慢，两年后的单桩竖向承载力几乎不再增长。

[关键词]  时间效应；压桩力；软土；竖向极限承载力；预测公式

中图分类号： TU473   文献标识码：A        文章编号：

作者简介：硕士,工程师,Email:mgmz@21cn.com。

Forecasting and testing study on time effect of vertical bearing capacity for single pile

YAO Mingfu

（Toyo Engineering (china) Co.,Ltd, Shanghai,200122,China）

Abstract: Based on the force of pressed pile, it was that had studied in-depth the formula of  force  of  pressed pile. The test was found that the value of ultimate bearing capacity for single pile increased more than the theoretical. Infrastructural design would bring greater economic benefit on time effect. A forecasting formula on time effect for the ultimate bearing capacity of single pile was obtained by regression analysis. Prediction of bearing capacity of single pile was achieved about any time. The limit of error was smaller both forecasting formula value and testing value. The predictable data were shown that the proposed method was feasible. Prediction data and test results were found that the ultimate bearing capacity of single pile added as time rising, with fast in the early stage and slow in the late. Vertical bearing capacity was no longer grow two years later.

Keywords: time effect; pressed pile; soft soil; vertical limited bear capacity; forecasting formula

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