PRACTICAL ALGORITHM FOR THE TIP BEARING CAPACITY OF LARGE DIAMETER BELLED PILE OVER SOFT SUBSTRATUM
-
摘要: 基于半无限空间内部点荷载作用下应力分布的Mindlin解答,提出一种确定存在软弱下卧层的大直径扩底桩桩端承载力特征值的实用方法。首先,利用圆形均布荷载作用下的Mindlin解,推求扩底桩桩端底面的附加应力公式。然后根据规范给出的单桩沉降计算公式确定扩底桩的最终沉降计算公式。最后,根据扩底桩沉降的容许值反算桩端底面的附加应力,进而确定扩底桩的端承力。通过工程实例,将计算结果与实测数据进行对比,两者吻合较好。Abstract: It is presented a new method to determine the tip bearing capacity characteristic value of large diameter belled pile on soft substratum according to the settlement.Compared to the presented methods,it is a converse procedure here.First of all,the additional stress corresponding to the settlements is calculated with the settlement formula of single-pile in the code.Then,the tip pressure is obtained by substituting the additional stress into the Mindlin solution for a circular uniform distributed load.At last,the tip bearing capacity is obtained.Those factors,such as the bottom diameter,pile length,thickness and physical and mechanical properties of the bearing layer and substratum,etc,which effect the tip bearing capacity of large diameter belled pile on soft substratum,were considered in this method.
-
Key words:
- belled pile /
- tip bearing capacity /
- soft substratum /
- Mindlin solution
-
杨同新.有限厚土层上大直径扩底桩的端承力计算[J].冶金矿山设计与建设,1997,29(2):22-25; [2] 刘小文,刘祖德.软弱下卧层上大直径扩底桩端承力分析计算[J].勘察科学技术,2003(1):21-23; [3] 宰金璋,陈文,肖永正,等.层状土中扩底桩的性状分析及其工程应用[J].福建建筑,1994(1):19-24; [4] 李文娟.存在软弱下卧层的大直径灌注桩承载力非线性有限元分析[D].广州:华南理工大学,2004; [5] 郭星宇.扩底墩竖向承载性状的数值模拟[D].上海:同济大学,2007; [6] 张婧.存在软弱下卧层的大直径扩底桩竖向承载性状的数值模拟[D].上海:同济大学,2008; [7] Mindlin R D.Force at a Point inthe Interior of a Semi-Infinite Solid[J].Physics,1936,7(5):195-202; [8] 徐怀英.以明特林(Mindlin)公式为根据的地基中垂直应力的计算公式[J].土木工程学报,1957,4(4):485-497; [9] 顾宝和.根据变形确定扩底墩的轴向承载力[C]//中国工程勘察学术委员会第三届交流会议论文集.北京:中国建筑工业出版社,1987; [10] 高广运.黄土层中扩底墩基础的沉降计算和实测[J].工业建筑,1995,25(1):30-36.
点击查看大图
计量
- 文章访问数: 86
- HTML全文浏览量: 8
- PDF下载量: 85
- 被引次数: 0