土层锚固体复合界面单元形式及力学效应研究  

Soil anchor solid composite interface element form and mechanical effects

作　　者：毕冬宾 尤志嘉[1] 刘群[1] 王程程[1] 时健[1] 

机构地区：[1]山东科技大学土木工程与建筑学院,山东青岛266590

出　　处：《岩土力学》2017年第1期277-283,共7页Rock and Soil Mechanics

基　　金：国家自然科学基金资助项目(No.51274131)~~

摘　　要：土层锚固技术在岩土工程中已得到越来越广泛应用。简单介绍了已有土层锚固界面单元形式的研究现状,分析了土层锚固界面层的特点,提出一种新的复合界面单元,该复合界面单元由接触单元和实体单元构成,其中接触单元作为锚固体与土体之间的滑动摩擦单元,实体单元体现锚杆拉拔时对周围土体的体胀特性。利用ANSYS数值模拟软件,将新的复合单元应用于锚固体与土体之间的界面层,模拟并分析锚杆拉拔时界面层的破坏特征,得到随荷载增大时界面层剪应力分布的变化过程,并将界面层的破坏分为3个阶段,即线性阶段、滑移扩展阶段、滑移阶段。通过土层锚杆原位拉拔试验,得到土层锚杆拉拔的荷载-位移曲线,分析曲线变化特征,并对数值模拟结果进行了验证。Soil anchoring techniques have been widely used in geotectmical engineering. The present research status of soil anchor solid interface element form is briefly described, and the characteristics of the soil anchoring interface layer are analyzed. Then a new composite interface element is proposed, which consists of a contact element and a solid element. Wherein the contact element is considered as the sliding friction element between the anchor element and soil, and the solid element reflects swelling characteristics of surrounding soil body when rock bolt is drawn. The new composite element of the interface layer between the anchor and soil is implemented into ANSYS software. The failure characteristics of the interface layer are simulated and analyzed when rock bolt is drawn. The shear stress distribution process of the interface layer is obtained with the increase of loading. The destruction of the interface layer is divided into three stages, namely the linear stage, slippage expansion stage and slippage stage. The load-displacement curve of soil anchor pull-out is obtained by in-situ soil anchor drawing tests. Finally, the characteristics of the curve are analyzed and numerical results are verified as well.

关 键 词：土层锚固 接触界面 界面单元 本构关系 数值模拟 拉拔试验 

分 类 号：TU470[建筑科学—结构工程]