粗骨料对高温后沙漠砂混凝土抗压性能影响数值模拟  

Numerical Simulation of Coarse Aggregate Influence on Desert Sand Concrete Compressive Performance after Elevated Temperature

作　　者：杨维武 张倩 刘海峰[1] 陶仁光 YANG Wei-wu;ZHANG Qian;LIU Hai-feng;TAO Ren-guang(Civil and Hydraulic Engineering College, Ningxia University, Yinchuan 750021, China)

机构地区：[1]宁夏大学土木与水利工程学院,银川750021

出　　处：《科学技术与工程》2021年第36期15571-15580,共10页Science Technology and Engineering

基　　金：宁夏回族自治区自然科学基金(2020AAC03044);国家自然科学基金(52168034,51368048,11162015)。

摘　　要：为探讨高温作用对混凝土强度带来的不利影响以及解决中砂资源匮乏的问题,将沙漠砂混凝土(desert sand concrete,DSC)视为由粗骨料、沙漠砂砂浆及界面相组成的三相复合材料,采用随机骨料模型建模,对高温后沙漠砂混凝土单轴受压破坏过程进行了数值模拟,分析粗骨料体积含量及粒径大小对高温后沙漠砂混凝土单轴抗压性能的影响。结果表明:高温后沙漠砂混凝土的破坏相继发生于界面相、界面相周边砂浆及外围砂浆,混凝土最终沿近对角线方向发生斜向破坏;随粗骨料体积含量增加,沙漠砂混凝土抗压强度先增大后减小,体积含量45%时,抗压强度最大;相对于最小粒径与中间粒径,粗骨料最大粒径对高温后沙漠砂混凝土抗压强度的影响更为显著,研究结果可为沙漠砂混凝土的应用提供理论依据。In order to explore the adverse effects of high temperature on concrete strength and solve the lack problem of medium sand resources,desert sand concrete(DSC)was regarded as a three-phase composite material,which was composed of coarse aggregate,desert sand mortar and interfacial phases.Random aggregate model was used for modeling,and DSC failure process under uniaxial compression after elevated temperature was numerically simulated.The influences of coarse aggregate volume content and particle size on DSC uniaxial compressive performance after elevated temperature were analyzed.The results show that the DSC failure after elevated temperature occurs successively in the interface phase,the mortar around the interface phase and the peripheral mortar.Concrete eventually breaks diagonally along the diagonal direction.With increasing the coarse aggregate volume content,DSC compressive strength is expanded firstly and then decreased.When the volume content is 45%,compressive strength reaches the highest.Compared with coarse aggregate middle particle size and minimum particle size,influence of maximum particle size on the change in compressive strength is more significant.The research results can provide a theoretical basis for DSC application.

关 键 词：沙漠砂混凝土(DSC) 粗骨料 体积含量 粒径大小 抗压强度 

分 类 号：TU377[建筑科学—结构工程]