沙漠砂替代率对冻融环境下混凝土抗压性能的影响  

Influence of Desert Sand Replacement Rate on Compressive Performance of Concrete in Freeze-thaw Environment

作　　者：孟浩 杨维武 刘海峰[1] MENG Hao;YANG Weiwu;LIU Haifeng(School of Civil and Hydraulic Engineering,Ningxia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学土木与水利工程学院,宁夏银川750021

出　　处：《宁夏工程技术》2023年第1期49-55,共7页Ningxia Engineering Technology

基　　金：国家自然科学基金资助项目(52168034,11162015);宁夏自然科学基金资助项目(2020AAC03044)。

摘　　要：为了研究冻融循环对沙漠砂混凝土力学性能的影响,采用沙漠砂部分替代中砂,并与粉煤灰复掺制备沙漠砂混凝土,通过慢冻法对沙漠砂混凝土在不同温度(-20,-30,-40℃)下进行冻融循环,探究沙漠砂替代率、温度和冻融循环次数对混凝土抗压强度和超声波在混凝土中传播速度的影响。结果表明:随着冻融循环次数的增加,沙漠砂混凝土抗压强度和超声波波速均呈减小趋势;随着温度降低,沙漠砂混凝土抗压强度和超声波波速均呈减小趋势;随着沙漠砂替代率的增加,混凝土抗压强度呈现先增大后减小的趋势,当沙漠砂替代率为40%时,其抗压强度达到最大值。To study the influence of freeze-thaw cycles on the mechanical properties of concrete,compression strength experiments of concrete mixed with desert sand and fly ash(DSC)after freezing and thawing cycles at different low temperatures(-20℃,-30℃and-40℃)were carried out.The influence of desert sand replacement rate(DSRR),temperature and number of freezethaw cycles on DSC compressive strength and ultrasonic velocity was analyzed.The regression models between DSC compressive strength,ultrasonic velocity and temperature,DSRR and number of freeze-thaw cycles were established.The results show that as the number of freeze-thaw cycles increases,the DSC compressive strength and ultrasonic velocity decrease.When the temperature decreases,the DSC compressive strength and ultrasonic velocity decrease.With the increase in DSRR,DSC compressive strength firstly increase and then decrease.When the DSRR is 40%,its compressive strength reaches the maximum.

关 键 词：沙漠砂混凝土 冻融循环 抗压强度 超声波波速 

分 类 号：TU528[建筑科学—建筑技术科学]