（1 同济大学土木工程学院建筑工程系， 上海 200092; 2 国网四川省电力公司经济技术研究院， 成都 610041）

［摘要］对不同宽高比混凝土基础进行上拔试验，并运用有限元软件ABAQUS对不同宽高比混凝土独立扩展基础进行上拔数值模拟，通过将有限元分析结果与试验结果进行对比，验证了有限元方法的有效性。采用建立的数值模型进一步进行有限元分析，研究了宽高比、斜边坡度等因素对混凝土扩展基础截面承载性能的影响。在此基础上，基于有效宽度的概念，引入有效宽度修正系数k、坡度修正系数j来考虑宽高比与斜边坡度对等效内力臂系数的影响，并提出适用于基础抗拔计算的截面上部配筋计算公式。结果表明，基于有限元得出的修正系数与建议修正系数吻合度较高，误差在1%～3-4%之间，从而证明了提出的建议修正方法的合理性。

［关键词］大宽高比； 斜边坡度； 混凝土独立扩展基础； 有限元分析； 抗拔设计方法

中图分类号：TU470+.3文献标识码：A文章编号：1002-848X(2018)15-0098-07

Study on design method for uplift capacity of concrete isolated spread foundation with large width-to-height ratio

Li Yuanqi1, Qin Xiaoliang1, Luo Jinhui1, Wang Wenguang2, Luo Le2

(1 Department of Structural Engineering, College of Civil Engineering, Tongji University, Shanghai 200092, China; 2 State Grid Sichuan Economic Research Institute, Chengdu 610041, China)

Abstract:Concrete foundations with different width-to-height ratio were tested under the uplift load and the finite element software ABAQUS was applied to numerical simulation of concrete isolated spread foundations with large width-to-height ratio under uplift load. The results of finite element analysis were compared with experimental results, which verified the validity of the finite element analysis method. Then, several finite element models were built to further study the effect of factors, such as width-to-height ratio and hypotenuse slope, on the bearing capacity of concrete isolated spread foundations. On this basis, the effective width correction coefficient k and slope correction coefficient j were introduced to consider the effect of width-to-height ratio and hypotenuse slope on the equivalent coefficient of the arm of internal force in cross section based on the concept of effective width. In addition, a suggested formula for the reinforcement calculation which is suitable to the uplift calculation was proposed. It was shown that the correction coefficient based on the finite element agreed well with the recommended correction coefficient, and the error range was between 1% and 3-4%, which proves that the recommended correction method proposed  is reasonable.

Keywords:large width-to-height ratio; hypotenuse slope; concrete isolated spread foundation; finite element analysis; design method for uplift capacity

*国家电网科技项目（52199915002M）。

作者简介：李元齐，博士，教授，博士生导师，Email:liyq@tongji.edu.cn。