往复压载下纤维增强混凝土力学行为退化及本构关系  

Mechanical Behavior Degradation and Constitutive Relationship of Fiber Reinforced Concrete Under Reciprocating Compression

作　　者：刁静[1] 赵雪飞[2] 吕圆芳 卢同平 DIAO Jing;ZHAO Xue-fei;LV Yuan-fang;LU Tong-ping(Henan Polytechnic Institue,Nanyang 473000,China;School of Civil Engineering,Zhengzhou University,Zhengzhou 450001,China;College of Civil Engineering,Longdong University,Qingyang 745000,China)

机构地区：[1]河南工业职业技术学院,河南南阳473000 [2]郑州大学土木工程学院,河南郑州450001 [3]陇东学院土木工程学院,甘肃庆阳745000

出　　处：《水电能源科学》2024年第9期98-101,共4页Water Resources and Power

基　　金：国家自然科学基金项目(51274174)。

摘　　要：为研究钢纤维混凝土在往复轴压荷载下的力学性能及其本构关系,开展单轴往复压缩试验,以不同纤维掺量和长径比为变量,探究钢纤维混凝土的力学行为退化及损伤演化规律。结果表明,与单调加载相比,往复加载作用下钢纤维混凝土试件强度有轻微退化;混凝土塑性应变累积随钢纤维体积掺量的增加而大幅降低,弹性刚度退化率随之增大,但对纤维长径比的影响不显著;应力退化率随卸载应变呈先减小后增大的变化趋势;基于力学行为退化现象和纤维增强效应,建立了钢纤维混凝土往复轴压下混凝土损伤演化模型,与试验结果进行比较发现该模型与试验数据吻合较好。To study the mechanical properties and constitutive relationship of steel fiber reinforced concrete under ci re-procating axial compression loads,this paper conducted uniaxial reciprocating compression tests.Different fiber tents con-and length-diameter ratio were taken as experimental variables to explore the mechanical behavior degradation and damage evolution of steel fiber reinforced concrete.Compared with monotonic loading,the results show that the strength of steel fiber reinforced concrete specimens under reciprocating loading exhibits slight degradation;The accumulation of plastic strain in concrete decreases significantly with the increase of steel fiber volume fraction,and the degradation rate of elastic stiffness increases accordingly,but the effect of fiber length to diameter ratio is not significant;The stress dation degra-rate of concrete shows a trend of first decreasing and then increasing with the unloading strain;A damage evolution model for steel fiber reinforced concrete under reciprocating axial compression was established based on the phenomenon of mechanical behavior degradation and fiber reinforcement effect.Comparison of experimental results show that the el mod-was in good agreement with experimental data.

关 键 词：钢纤维混凝土 往复轴压 刚度退化 应力退化率 损伤本构关系 

分 类 号：TV431.3[水利工程—水工结构工程]