再生粗骨料混凝土梁受弯性能试验研究  

Experimental research on flexural property of recycled concrete beams with coarse aggregate

作　　者：杨丹 陈科 王汝恒[1] 王磊[1] YANG Dan;CHEN Ke;WANG Ruheng;WANG Lei(School of Civil Engineering and Architecture,Southwest University of Scienceand Technology,Mianyang 621010,China)

机构地区：[1]西南科技大学土木工程与建筑学院

出　　处：《四川建筑科学研究》2019年第4期54-59,共6页Sichuan Building Science

基　　金：国家自然科学基金(51508482);“十二五”农村领域国家科技支撑计划(2015BAL03B03);西南科技大学研究生创新基金(18ycx090)

摘　　要：为研究再生粗骨料(RCA)取代率对混凝土梁正截面受力性能的影响,对5根再生粗骨料混凝土简支梁进行了四点弯加载试验,以再生粗骨料取代率为试验变量,其质量分数分别为0%、30%、50%、70%及100%,主要研究和分析了不同再生粗骨料取代率的混凝土梁的裂缝发展、开裂荷载、破坏形态特征、抗弯承载力及变形性能等。对比分析表明:当再生粗骨料取代率为30%、50%、70%及100%时,与普通混凝土梁相比,再生粗骨料混凝土梁的极限承载力分别降低了6.98%、12%、16%和16.68%,裂缝数量及跨中挠度显著增加;梁正截面平均应变符合平截面假定,其破坏形态特征和荷载位移曲线与普通混凝土梁相似;按现有规范计算再生粗骨料混凝土梁的极限抗弯承载力安全储备不足,计算再生粗骨料混凝土梁的抗弯承载力时考虑再生粗骨料取代率因素,得到的计算值与试验值吻合较好,且变异系数较小。The test of section flexural performance of recycled concrete beams with different recycled coarse aggregate replacement ratios were conducted to investigate the mechanical characteristics of normal sections.In this paper,there are five reinforced recycled coarse aggregate concrete specimens with the same structure involved,its recycled coarse aggregate replacement ratios are 0%,30%,50%,70%and 100%,respectively.The test analyzed the effects of different recycled coarse aggregate replacement ratio on cracking load,ultimate load,deflection,crack and damage process of beams by a one-way loading way.Compared with ordinary concrete beams,the ultimate bearing capacity can be reduced by 6.98%,12%,16%and 16.68%when the replacement ratio(by mass)is to 30%,50%,70%and 100%of test beams,the crack number and deflection increase.The plane section assumptions is applicable for recycled coarse aggregate beams,its failure pattern and load-deflection curve are similar to normal noes under the same reinforcement ratio.The present ultimate load bearing capacity formula in code is no longer applicable,it should be multiplied by the corresponding correction coefficient of recycled coarse aggregate replacement ratio.

关 键 词：再生粗骨料混凝土梁 受弯性能 取代率 裂缝 极限承载力 

分 类 号：TU375.1[建筑科学—结构工程]