Characterization of the Inelastic Constitutive Behavior of Concrete Materials

9313076陈混凝土材料表现出两种极端的行为：即延性流动和脆性断裂。在一定条件下，材料的脆性行为和延性行为之间会发生转变，但目前的破坏准则和相关理论都没有对这两种模式进行区分。理想情况下，本构方程应既反映变形模式，又反映脆性-韧性转变的可能性。此外，由于混凝土材料高度不均匀，特别是在裂缝普遍存在的软化区域，宏观观察是不够的。因此，基于对混凝土细观力学的最新基本认识，提出了统一的弹塑性损伤理论。因此，新的软件开发系统对于新材料模型的充分开发和测试是必要的。一个面向结构工程的软件开发环境，侧重于软件的可重用性。

9313076 Chen Concrete materials exhibit both extremes of behavior: that is, ductile flow and brittle fracture. Under certain conditions, a transition between brittle and ductile behavior occurs, yet no distinction between the two modes has been made in any of the present failure criteria and related theories. Ideally constitutive equations should reflect both the modes of deformation and the possibility of a brittle-ductile transition. Also, because concrete materials are highly non-homogeneous, especially in the softening regime where cracking is widespread, macroscopic observations are not sufficient. Therefore, a unified elastic- plastic-damage theory is proposed, which is based on recent fundamental understanding of concrete micro-mechanics. New software development systems are thus necessary for adequate development and testing of new material models. A software development environment for structural engineering focused on software reusability.