损伤模型为基础的钢筋混凝土构件

Damage Model Based Reinforced-Concrete Element

损伤模型为基础的钢筋混凝土构件

Chee Kiong Soh1; Yu Liu2; Yue Xing Dong3; and Xin Zheng Lu4

Abstract:

In this paper, the damage in concrete around a reinforcement bar is examined, and three types of damage in concrete and at the concrete-rebar interface are defined. Based on these definitions, a three-dimensional damaged reinforced-concrete ~DRC! element is proposed. The element consists of a 10-node concrete element, a two-node rebar element, and a four-node concrete-rebar interface

element. Experiments were carried out to obtain the parameters for the bond damage evolution equation. The proposed DRC element is implemented as a user-defined element of MSC MARC2000, a commercial finite-element analysis software package. Two numerical examples were examined, and the results show that the DRC element can simulate the bond deterioration in reinforced-concrete structural members with sufficient rationality, accuracy, and efficiency.

DOI:10.1061/~ASCE!0899-1561~2003!15:4~371!

CE Database subject headings: Damage; Models; Concrete, reinforced.

摘要：

在本论文中，讨论了加强钢筋周围的混凝土的破坏情况，将混凝土钢筋破坏界面的界定为3种类型。根据这些定义，提出了高强混凝土的三维破坏原理。这个原理包含三个元素，分别是一个10节点的混凝土构件，两节点筋单元，和一个四节点的混凝土钢筋接口。进行了试验，以取得弯矩破坏公式的有关参数。数据控制记录被建议作为MSC MARC2000的一个用户定义元素，MSC MARC2000是一个商用有限元分析软件包。两个数值实例研究结果表明，数据控制记录元素可以合理精确有效的模拟高强混凝土黏结失效。

DOI: 10.1061/~ASCE!0899-1561~2003!15:4~371!

CE数据库主题词：破坏;模型;混凝土，加固。

Introduction

In the design and analysis of reinforced-concrete structures,the bond between the reinforcement bar and concrete is one of the important factors that must be properly accounted for.The shear bond, in particular, is the main load-carrying mechanism between the concrete and its reinforcement in the longitudinal direction of the rebars. Although perfect bonding can be assumed when little or no stress transfer occurs between the concrete and rebar, slip at the concrete-rebar interface usually occurs when

reinforced-concrete structures are loaded, especially in cases when high stress at the contact interface and at the end anchorage exists. It has been shown that it is essential to include bond-slip in the analysis of reinforced-concrete structures. The bond stress is directly related to the slip of the interface.The behavior of the interface will deteriorate after the slip reaches a certain level, and as a result of damage development nonlinear and softening behavior will appear in the bond stress-slip curves. These must be fully simulated in the reinforced concrete structure analysis. While the various bond problems can be treated separately using contact elements or interface elements，it is not easy to take into account the interaction between the cracking of concrete and the bond deterioration of the concrete-rebar interface. At the same time, these concrete

interface-rebar meshing techniques usually need many elements in the finite-element analysis for accurate results to be obtained.

导言

在设计和分析高强混凝土结构中，巩固钢筋混凝土之间的黏结是最主要因素之一，剪切粘固力尤其是主要的承载机制之间的混凝土及其加固中的纵向方向的钢筋。当混凝土和钢筋很少或没有应力传递发生关系时，虽然完美的结合可以假定，但当钢筋混凝土结构有荷载时，尤其是在接触面上和端部锚具存在压力比较大时，在钢筋混凝土接口处通常发生滑移。已经表明它是必不可少的，包括在分析钢筋混凝土结构的滑移。黏结力是直接关系到接触面上的滑移。当下滑到一定程度时接触面性能就会变差，因而损害非线性与性能软化出现的滑动应力曲线的发展，这些必须有充分的模拟在混凝土结构分析中。而各种黏结的问题可以分开处理，采用接触单元或界面元素，这是一个不太容易顾及互动，混凝土裂缝和黏结失效的混凝土钢筋界面。与此同时，这些混凝土界面-钢筋网格化技术通常需要许多要素，在有限元分析，为准确的结果，以期获得。

In this paper, a 12-node 3D damaged reinforced-concrete element is developed based