- 摘 要
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(西安建筑科技大学土木工程学院, 西安 710055)
[摘要]通过模型试验研究了竖向上拔荷载作用下长径比为30时斜桩的承载变形和荷载传递性状,并与同条件直桩的性状进行了比较。结果表明,在相等桩顶竖向上拔荷载作用下,斜桩竖向上拔量大于直桩竖向上拔量;斜桩桩顶竖向上拔量随桩身倾角的增大而增加。在桩顶竖向上拔荷载作用下,抗拔直桩与抗拔斜桩桩身轴力上拔量分布具有一定的相似性。斜桩桩身弯矩主要分布在1/2桩长范围内,且随着桩身倾角的增大而增大;而最大弯矩所处的深度与桩身倾角无关。抗拔直桩与抗拔斜桩的平均侧摩阻力都是从上部开始发挥并往下传递;随着上拔荷载的增加,桩身上部平均侧摩阻力的数值变化很小,而桩身中下部平均侧摩阻力迅速增长。抗拔直桩与抗拔斜桩端部平均侧摩阻力都表现出弱化现象。
[关键词]斜桩; 模型试验; 抗拔承载力; 轴力; 弯矩; 侧摩阻力
中图分类号:TU473文献标识码:A文章编号:1002-848X(2017)15-0093-04
Experimental study of model test of uplift inclined piles in sand
Feng Zhiyan, Ren Zixiong, Li Sheng
(College of Civil Engineering, Xi′an University of Architecture and Technology, Xi′an 710055, China)
Abstract:Based on the model tests, the bearing capacity and load transfer behavior of inclined piles with length-diameter ratio of 30 under the vertical uplift load were studied, and the results were compared with straight pile under the same conditions. The results show that under the same vertical uplift load on pile top, the vertical displacement of the inclined pile is greater than the vertical displacement of the straight pile, and top vertical uplift displacement of inclined pile increases with the increase of pile inclination. Under the vertical uplift load on pile top, distributions of pile axial force of straight uplift pile and inclined uplift pile have a certain similarity. Bending moment of the inclined pile is mainly distributed in the range of 1/2 pile length, and increases with the increase of pile inclination. The depth where the maximum bending moment locates has no relation with pile body inclination. The average lateral frictional resistance of straight uplift pile and inclined uplift pile emerges from the upper part to pass down to lower parts. Along with the increase of uplift load, the average lateral frictional resistance of upper part of pile has very small change in numerical value, and the average lateral frictional resistance of middle and lower parts of pile has a rapid growth. The lateral frictional resistance of the top of straight uplift pile and inclined uplift pile are both weakened.
Keywords:inclined pile; model test; pullout capacity; axial force; bending moment; lateral frictional resistance
作者简介:冯志焱,博士,副教授,Email:zyfeng5769@xauat.edu.cn。