冲击荷载下混凝土本构模型及损伤延迟指标的参数研究  

PARAMETER STUDY ON CONSTITUTIVE MODEL OF CONCRETE UNDER IMPACT LOAD AND INDEX FOR DAMAGE DELAY

作　　者：林峰[1] 匡昕昕[1] 顾祥林[1] 

机构地区：[1]同济大学建筑工程系,上海200092

出　　处：《振动与冲击》2008年第3期131-135,共5页Journal of Vibration and Shock

基　　金：国家自然科学基金资助项目(50538050)

摘　　要：冲击荷载作用下混凝土材料中会引起高应变率。以损伤理论为基础,Eibl和Schmidt-Hurtienne模型考虑了高应变率作用下混凝土的"记忆效应",较客观地反映了混凝土的动态力学行为。在作者以前的研究中,采用循环逼近的方法可以确定该模型中参数取值,并引入了"相对半值损伤积累时间"指标以定量评价混凝土的动力损伤延迟,但该法以及指标的确定需要较多的数值消耗,难以应用于结构动力分析。为便于实际应用,研究模型中参数和指标在混凝土立方体抗压强度30MPa^60MPa以及应变率0.0001s-1~100s-1范围内的取值,对模型中参数和指标的取值分别进行数据拟合并给出了相应表达式。Based on damage theory, the model suggested by Eibl and Schmidt-Hurtienne, in which the memory effect is taken into account, is usually considered to be able to describe the dynamic behavior of concrete properly. In the authors’ previous work, a step-by-step approximation approach was used to obtain the parameters in the above model, and an index named 'relative time up to accumulate half damage' was suggested to evaluate the dynamic damage delay of concrete. However, the approach and the determination of the index require considerable numerical effort, which makes it difficult for the users to apply them in structural analysis. For practical application a study on the model parameters and the index was performed, with the concrete compressive strength from 30 to 60MPa and strain rate from 0.000 1 to 100s-1. The quantitative expressions for the parameter values and the index were derived respectively with a regression analysis approach.

关 键 词：混凝土 本构模型 损伤延迟 参数研究 回归分析 

分 类 号：TU528.01[建筑科学—建筑技术科学]