砖混建筑废弃物再生碎砖混凝土耐久性研究  

Study on durability of recycled brick concrete from brick and concrete building wastes

作　　者：王贵美 WANG Guimei(School of Mechanics and Civil Engineering,China University of Mining and Technology,Xuzhou 221116,China;Ascity Design Stock Co.,Ltd.,Hangzhou 310015,China)

机构地区：[1]中国矿业大学力学与土木工程学院,江苏徐州221116 [2]泛城设计股份有限公司,浙江杭州310015

出　　处：《混凝土》2024年第6期161-165,共5页Concrete

摘　　要：砖混建筑废弃物经过破碎筛选可以制成再生碎砖粗骨料,将其与水泥、河砂细骨料等主要原料混合,可以制备再生碎砖混凝土试件。为探究再生碎砖混凝土的耐久性,通过抗氯离子渗透性、干湿循环、冻融循环试验,分析不同水灰比以及再生碎砖粗骨料、粉煤灰、硅粉含量下混凝土试件的抗压强度、氯离子迁移系数以及质量损失率和动弹性模量的变化,并分析了混凝土试件在不同冻融介质中的质量损失率和动弹性模量的变化情况。结果表明:当碎砖粗骨料、粉煤灰、硅粉掺量分别为15%、16%、7%,水灰比为0.4时,再生碎砖混凝土试件的抗压强度、动弹性模量指标最大,抗氯离子渗透能力最优,质量损失率最小,耐久性最好;再生碎砖混凝土试件在水介质中的耐久性最大,在4%氯化钠溶液的耐久性最小,在4%硫酸钠溶液的耐久性居中。Brick concrete construction waste can be made into recycled broken brick coarse aggregate through crushing and screening,and mixed with cement,river sand fine aggregate and other main raw materials to prepare recycled broken brick concrete specimens.In order to explore the durability of recycled broken brick concrete,the changes of compressive strength,chloride ion migration coefficient,mass loss rate and dynamic elastic modulus of concrete specimens under different water cement ratio and the content of recycled broken brick coarse aggregate,fly ash and silica fume were analyzed through chloride ion permeability resistance,dry wet cycle and freeze-thaw cycle tests,and the changes of mass loss rate and dynamic elastic modulus of concrete specimens in different freeze-thaw media were analyzed.The results show that when the coarse aggregate,fly ash and silica fume are added at 15%,16% and 7% respectively,and the water cement ratio is 0.4,the compressive strength,dynamic elastic modulus,chloride ion penetration resistance,mass loss rate and durability of recycled brick concrete specimens are the highest.The durability of recycled brick concrete specimens in water medium is the highest,that in 4% sodium chloride solution is the lowest,and that in 4% sodium sulfate solution is the middle.

关 键 词：砖混建筑废弃物 再生碎砖混凝土 耐久性分析 抗压强度 水灰比 冻融介质 

分 类 号：TU528.041[建筑科学—建筑技术科学]