(1 北京科技大学土木与环境工程学院，北京 100083； 2 燕山大学建筑工程与力学学院，秦皇岛 066004；3 秦皇岛燕盛岩土有限公司，秦皇岛 066000)

［摘要］为了研究深基坑桩锚支护结构中锚杆的内力与变形的影响因素，采用理论推导、现场试验与数值模拟相对比的方法。运用半无限边界上一点作用垂直力的布辛涅斯克(Boussinesq)问题的位移解，推导出锚杆锚固段的轴力分布的公式。运用有限差分法，采用岩土软件FLAC3D建立深基坑桩锚支护结构的仿真模型，并对支护结构中锚杆的内力与变形进行数值模拟。分析结果表明：理论计算、现场试验与数值模拟得到的结果基本吻合，表明由布辛涅斯克问题推导出锚杆锚固段轴力分布函数是正确的，为锚杆的计算提供了一种理论依据；用FLAC3D数值模拟深基坑支护结构中锚杆的内力与变形是可行的。在锚杆的张拉过程中，锚杆在自由段的轴力和变形量最大，从锚固段开始，锚杆的轴力和变形量逐渐减小，最后趋于零。

［关键词］锚杆；试验；数值模拟；轴力

中图分类号：TU753.1文献标识码：A文章编号：1002-848X(2011)08-0134-04

Study on distribution of axial force in prestressed anchor for deep foundation pit

Wu Chongfu^1，2，Li Changhong¹，Bi Xin²，Feng Qingbo³(1 School of Civil and Environmental Engineering，University of Science and Technology Beijing，Beijing 100083，China;2 School of Civil Engineering and Mechanics, Yanshan University, Qinhuangdao 066004，China;3 Qinhuangdao Yansheng Geotechnical Engineering Co., Ltd., Qinhuangdao 066000，China)

Abstract:In order to study the influencing factors about internal forces and deformations of anchor in deep foundation pit, the theoretical derivation, field experiment and numerical simulation were carried out. Using Boussinesq solution on the semi-infinite boundary of vertical point force, a function was deduced for anchor axial force distribution. By using the finite difference method FLAC3D, simulation model of deep foundation pit was established, and internal force and deformation of bracing structure were calculated. The results show that the theoretical calculation, the field experiment and numerical simulation results are agreed with each other basically. The upper deduced function about anchor axial force distribution is correct, which provides a theoretical basis for calculating relative forces. It is feasible for using FLAC3D to simulate the anchor force and deformation of deep foundation pit bracing structure. In the process of the anchor bolt, the axial force and deformation on free part are large. Meanwhile, axial force and deformation decrease gradually along anchored length, and reduce to zero finally.

Keywords:anchor; experiment; numerical simulation; axial force

*河北省建设厅研究项目资助（2010\|221）。

作者简介：武崇福，硕士，副教授，Email：wcf11@263.net。

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