考虑加载历史的约束混凝土动力本构模型

Dynamic Constitutive Model for Confined Concrete Based on a Consideration of Loading History

客观描述高应变率作用下的约束混凝土的力学行为需要考虑加载历史.将具有该特点的Eibl和Schmidt-Hurtienne混凝土动力模型推广,使之适用于约束混凝土.采用四段式约束混凝土单轴受压应力-应变曲线,以确定模型中的静力损伤发展;利用混凝土动力试验结果并通过数值迭代,给出约束混凝土动力损伤延迟中参数的确定方法,从而得到了模型中的动力损伤延迟.算例表明,给出的方法可以较客观地描述一定范围应变率作用下约束混凝土的力学行为.

To objectively describe the behavior of confined concrete under hlgh strata rates me loading history has to be taken into account. The＇concrete model with this character suggested by Eibl ＆ Schmidt-Hurtienne is applied to the model of confined concrete. The uniaxial stress-strain curve with four-parts for confined concrete under compression is proposed to obtain the model term ＂static damage evolution＂. Based on the experimental results of concrete, the parameters to the model term ＂dynamic damage delay＂ are derived with an iteratively numerical approach. As a result, the ＂dynamic damage delay＂ can be determined. Examples show that the dynamic behavior of confined concrete can be predicted with the proposed approach in a proper manner.