含初始孔隙的堆石混凝土动态抗压性能研究  

Dynamic Compressive Properties of Rock-Filled Concrete with Initial Pores

作　　者：余雷 乔浩洋 王国冀 刘云柯 任涛 杨韬 YU Lei;QIAO Haoyang;WANG Guoji;LIU Yunke;REN Tao;YANG Tao(College of Civil Engineering,Guizhou University,Guiyang 550025,China)

机构地区：[1]贵州大学土木工程学院,贵阳550025

出　　处：《硅酸盐通报》2024年第11期4036-4046,4082,共12页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金(52069004);贵州省科学技术基金(黔科合基础-ZK[2021]一般293)。

摘　　要：初始缺陷被视为影响混凝土力学特性的主要因素之一。本文采用聚苯乙烯(EPS)颗粒预制了堆石混凝土(RFC)的初始缺陷,以孔隙率定量缺陷含量,系统开展了4种孔隙率RFC在4种应变速率下的单轴压缩试验,探究了应变速率与孔隙率对RFC破坏模式、抗压强度、弹性模量和临界应变的影响。结果表明:不同工况下RFC破坏模式均呈现类似“沙漏”型;RFC的抗压强度、弹性模量和临界应变均具有应变速率强化效应。随着孔隙率增加,RFC的抗压强度、弹性模量和临界应变对应变速率的敏感性不断减弱;相较于应变速率而言,孔隙率对RFC抗压强度、弹性模量与临界应变的影响更为显著。此外,基于Sargin模型,构建了含初始孔隙的RFC动态本构模型,该模型可用于描述含初始孔隙的RFC在低应变速率下的力学行为。Initial defects are identified as one of the root causes affecting the mechanical properties of concrete.In this paper,expanded polystyrene(EPS)particles were utilized to prefabricate initial defects of rock-filled concrete(RFC),and the defect content was quantified by porosity.Uniaxial compression tests of four porosities of RFC at four strain rates were systematically conducted,and the effects of strain rate and porosity on RFC failure modes,compressive strength,elastic modulus,and critical strain were studied.The results show that the RFC failure modes under different operating conditions are similar to the“hourglass”type.The compressive strength,elastic modulus and critical strain of RFC all have strain rate strengthening effect.As the porosity increases,the sensitivity of RFC compressive strength,elastic modulus,and critical strain to strain rate decreases.Compared with strain rate,the effect of porosity on compressive strength,elastic modulus,and critical strain of RFC is more significant.Additionally,based on the Sargin model,a dynamic constitutive model of RFC with initial pores is constructed.It is used to illustrate the mechanical behavior of RFC with initial pores at low strain rates.

关 键 词：堆石混凝土 聚苯乙烯颗粒 单轴压缩 应变速率 孔隙率 本构模型 

分 类 号：TU528[建筑科学—建筑技术科学]