再生混凝土的冲击力学特性及本构模型研究  

Study on impact mechanical properties and constitutive model of recycled concrete

作　　者：李月霞 田国宾 LI Yuexia;TIAN Guobin(Department of Architectural Engineering,Yuncheng Vocational and Technical University,Yuncheng 044000,China;School of Architectural and Civil Engineering,Xi′an University of Science and Technology,Xi′an 710050,China)

机构地区：[1]运城职业技术大学建筑工程系,山西运城044000 [2]西安科技大学建筑与土木工程学院,陕西西安710050

出　　处：《混凝土》2023年第1期183-187,192,共6页Concrete

基　　金：国家自然科学基金(51174159)。

摘　　要：为了解再生混凝土的冲击力学性能,以粗骨料全取代下的再生混凝土试样为材料,利用霍普金森压杆对其进行不同冲击气压下的动态单轴压缩试验,对其动力学特性进行分析,结果表明:冲击荷载下,再生混凝土的应力-应变曲线分为3个阶段,即线弹性阶段、塑性发展阶段和破坏阶段;当应变率小于60 s^(-1)时,再生混凝土的应力-应变曲线存在明显的回弹现象;再生混凝土的动力学参数存在明显的应变率增强效应,其中动态峰值应力与应变率呈线性关系,动态弹性模量与应变率呈指数关系,动态应力增长因子与应变率的自然对数呈指数关系;建立的基于界面脱黏损伤的再生混凝土动态本构模型与试验曲线吻合度良好,该模型可以表征再生混凝土在冲击荷载下的本构曲线特征。为再生混凝土冲击力学性能、动力参数及本构关系的研究提供指导和依据。To obtain the impact mechanical properties of recycled concrete,the samples of recycled concrete under the total substitution of coarse aggregate were used as materials,and the dynamic uniaxial compression tests under different impact air pressure were carried out by using Hopkinson pressure bar.The results showed that,the recycled concrete stress-strain curves under the impact loading can be divided into three stages,including the linear elastic stage,the plastic development stage and failure stage.When the strain rate is less than 60 s^(-1),the stress-strain curves of recycled concrete has an obvious springback phenomenon.The dynamic parameters of recycled concrete have obvious strain rate enhancement effect,in which the relationship between dynamic peak stress and strain rate are linear,the dynamic elastic modulus and strain rate is exponential,and the dynamic stress growth factor and natural logarithm of strain rate is exponential.The dynamic constitutive model of recycled concrete based on interfacial debonding damage is in good agreement with the test curves,and the model can represent the characteristics of the constitutive curves of recycled concrete under impact load.The research can provide guidance and basis for the research of impact mechanical properties,dynamic parameters and constitutive relations of recycled concrete.

关 键 词：再生混凝土 动态压缩试验 冲击力学特性 动态本构模型 

分 类 号：TU528.01[建筑科学—建筑技术科学]