基于Wiener理论的RAC抗硫酸盐可靠性评价  

Evaluation of RAC sulfate resistance reliability based on Wiener theory

作　　者：张丰川 牛昌林 曹辉 关利娟 ZHANG Fengchuan;NIU Changlin;CAO Hui;GUAN Lijuan(Gansu Tianshui Green Prefabricated Building Industry Development Co.,Ltd.,Tianshui 741000,China;Gansu Jiantou Technology R&D Co.,Ltd.,Lanzhou 730050,China;Western Center of Disaster Mitigation in Civil Engineering of Ministry of Education,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]甘肃天水绿色装配式建筑产业发展有限公司,甘肃天水741000 [2]甘肃建投科技研发有限公司,甘肃兰州730050 [3]兰州理工大学西部土木工程防灾减灾教育部工程研究中心,甘肃兰州730050

出　　处：《混凝土》2021年第6期29-33,38,共6页Concrete

基　　金：国家自然科学基金资助项目(51868044,51468039);甘肃省科技攻关项目(2017GS10844)。

摘　　要：再生混凝土(RAC)研究对于提高建筑垃圾率用率,改善建材使用环境具有重要意义.以0、30、50%再生粗骨料率和0、15%再生细骨料替代率的6种混凝土为研究对象,研究分析了粗、细骨料替代率对RAC含气量、坍落度、抗压及劈裂抗拉强度等基本物理力学的影响,并通过Wiener建模,得到了混凝土在硫酸盐干湿循环条件下的可靠度.结合SEM表征形貌,分析了RAC在硫酸盐环境下的腐蚀变化,其结果表明:由于再生骨料孔隙率、吸水率均高于天然砂石,使得混凝土含气量和坍落度随着再生骨料替代率增大而增大,且复合替代高于单独替代;单独替代力学性能较差,复合替代强度略有增加,30%~15%力学性能最佳;质量和动弹性模量退化量均能够较好反应RAC在不同干湿循环次数下的可靠性,质量退化量对硫酸盐侵蚀更敏感。The study on recycled concrete(RAC)is greatly significance for improving the rate and rate of construction waste and improving the use environment of building materials.In this study,0,30%,50%recycled coarse aggregate rate and 0,15%recycled fine aggregate replacement rate of 6 concrete as the research object,the influence of the replacement rate of coarse and fine aggregate on the gas content,slump,compressive strength,split tensile strength and other basic physical mechanics of RAC was studied and analyzed.Through Wiener modeling,the reliability of concrete under the condition of dry and wet cycle of sulfate was obtained.At the same time,the corrosion mechanism of RAC under the environment of sulfate was analyzed by combining SEM and other methods.The results show that because the porosity and water absorption of recycled aggregate are higher than that of natural sand,the gas content and slump of concrete increase with the replacement rate of recycled aggregate,and the composite replacement is higher than the individual replacement.The mechanical properties of single substitution were poor,the composite substitution strength was slightly increased,and the mechanical properties of 30%~15%were the best.Both mass degradation and dynamic elastic modulus degradation can better reflect the reliability of RAC under different dry and wet cycles,and mass degradation is more sensitive to sulfate erosion.

关 键 词：再生混凝土 硫酸盐腐蚀 干湿循环 WIENER 可靠性 

分 类 号：TU528.01[建筑科学—建筑技术科学]