基于数字图像法的桩-土接触面特性试验研究  

STUDY ON THE MECHANISM CHARACTERISTICS OF PILE-SOIL INTERFACE BASE ON DIGITAL IMAGE METHOD

作　　者：陈亚东[1] 王旭东[2] 蔡江东[1] 

机构地区：[1]淮阴工学院建筑工程学院,江苏淮安223001 [2]南京工业大学交通学院,南京210009

出　　处：《工业建筑》2012年第3期84-87,137,共5页Industrial Construction

基　　金：国家自然科学基金项目(50678083)

摘　　要：桩与土接触面的力学特性是桩-土共同作用研究中的一个重要课题。利用基于数字图像的非接触光学测量方法,通过室内模型试验,对密实砂土中桩-土接触面上荷载传递特性、剪切位移场及剪应变场分布规律进行研究。结果表明:密砂中单桩桩侧摩阻力与沉降关系呈软化型,桩侧摩阻力达到极限值所需桩身沉降约为桩横截面边长的3%。桩周土体剪切滑动区发生在有限范围的土体中,最大剪应变首先出现在桩顶及桩底附近土体中,而后向桩身中部发展,在极限荷载条件下,最大剪应变沿桩身呈"两头大中间小"的分布形式。试验结果为合理建立桩-土接触面模型和相关数值计算提供有益的参考。Mechanical behavior of pile-soil interface is an important project in the research field of pile-soil interaction. Using the digital image correlation method, the model tests of pile-soil interface mechanism characteristics were carried out in dense sand. The load transfer characteristics, the distribution regularities of shear displacement field and strain field were analyzed from the view of mesomechanics. The study results indicated that the relationship between pile shaft resistance and settlement presented softening behavior, and the settlement for ultimate shaft resistance was about three percent of pile side length. The shear sliding zone was restricted to the limited range around pile side. The maximum shear strain first appeared in pile top and pile tip, and then developed to the central part of pile. The distribution pattern of maximum shear strain along the pile shaft under ultimate load performed as big at both ends and small in the middle. These test results provided some useful references for determining reasonable pile-soil interface model and relevant numerical calculations.

关 键 词：接触面 数字图像 位移 剪应变 

分 类 号：TU473.1[建筑科学—结构工程]