混凝土搅拌站废水对C60混凝土抗冻性能的影响  

Effect of Wastewater from Concrete Mixing Plant on Frost Resistance of C60 Concrete

作　　者：席君毅 李勋 姚贤华 管俊峰 上官林建 柳利君 徐昭文 XI Junyi;LI Xun;YAO Xianhua;GUAN Junfeng;SHANGGUAN Linjian;LIU Lijun;XU Zhaowen(School of Civil Engineering and Communication,North China University of Water Resources and Electric Power,Zhengzhou 450045,China;China Construction Engineering Design&Research Institute Co.,Ltd.,Beijing 100037,China;State Key Laboratory of Eco-hydraulics in Northwest Arid Region,Xi′an University of Technology,Xi′an 710048,China;Science and Technology Office,North China University of Water Resources and Electric Power,Zhengzhou 450046,China;Zhengzhou Sanhe Hydraulic Machinery Co.,Ltd.,Zhengzhou 450000,China)

机构地区：[1]华北水利水电大学土木与交通学院,河南郑州450045 [2]中国中建设计研究院有限公司,北京100037 [3]西安理工大学省部共建西北旱区生态水利国家重点实验室,陕西西安710048 [4]华北水利水电大学科技处,河南郑州450046 [5]郑州三和水工机械有限公司,河南郑州450000

出　　处：《华北水利水电大学学报（自然科学版）》2023年第4期69-75,共7页Journal of North China University of Water Resources and Electric Power：Natural Science Edition

基　　金：国家自然科学基金项目(52179132);河南省杰出青年科学基金项目(232300421016);河南省科技攻关项目(232102320181);省部共建西北旱区生态水利国家重点实验室(西安理工大学)开放研究基金资助课题(2021KFKT-10);焦作市创新创业团队项目。

摘　　要：为了研究混凝土搅拌站废水对C60混凝土抗冻性能的影响,对废水替代率为0%、25%、50%、75%、100%的C60混凝土进行快速冻融循环试验。研究了不同废水替代率下C60混凝土的抗压强度损失率、质量损失率、相对动弹性模量和吸水率随冻融循环次数的变化情况。分析了不同废水替代率(0%、50%和100%)的C60混凝土冻融后的微观形貌及其变化规律。基于混凝土相对动弹性模量变化规律,建立了混凝土冻融损伤二次函数衰减模型。结果表明:与基准混凝土相比,废水的掺入降低了混凝土的抗冻性,废水替代率超过50%时,其对混凝土抗冻性影响较大。微观分析发现:与基准混凝土相比,废水的掺入增大了混凝土的孔隙数量,降低了混凝土的密实度;冻融循环100次后,各废水替代率下混凝土内部大孔的数量均呈增加的趋势;相同冻融循环次数下,随着废水替代率的增加,大孔数量显著增加,结构更加松散。建立的废水混凝土冻融损伤模型计算值与试验值吻合较好,可靠性较高。In order to study the effect of concrete mixing plant wastewater on the frost resistance of C60 concrete,the rapid freeze-thaw cycle test was carried out on C60 concrete with wastewater replacement rates of 0%,25%,50%,75%,and 100%.The changes in compressive strength loss rate,mass loss rate,relative dynamic elastic modulus,and water absorption rate of C60 concrete under different wastewater substitution rates were studied.The changes in microscopic morphology of C60 concrete before and after freeze-thaw were analyzed under different wastewater substitution rates(0%,50%,and 100%).Based on the change law of concrete relative dynamic elastic modulus,the attenuation model of concrete freezethaw damage quadratic function is established.The results are as follows.Compared with C60-0 concrete,the incorporation of wastewater reduced the frost resistance of concrete.When the substitution rate of wastewater exceeds 50%,it has a significant impact on the frost resistance of concrete.In addition,microscopic analysis found that,compared with C60-0 concrete,before freezing and thawing,the incorporation of wastewater increased the number of pores in concrete and decreased the compactness of concrete.After 100 freeze-thaw cycles,the number of large pores inside the concrete showed an increasing trend under various wastewater replacement rates.Under the same freeze-thaw cycles,with the increase of wastewater substitution rate,the number of macropores significantly increases and the structure becomes looser.The established damage model for wastewater concrete under freeze-thaw cycles has good agreement between the calculated values and experimental values with high reliability.

关 键 词：废水 抗冻性 强度损失 相对动弹性模量 二次函数衰减模型 

分 类 号：TU528[建筑科学—建筑技术科学]