大掺量矿物掺合料纤维增强轻骨料混凝土的抗疲劳性能  

Fatigue Resistance of Fiber Reinforced Lightweight Aggregate Concrete with High Content Mineral Admixture

作　　者：李海礁 王加军 韩希平 陶琦 张仕龙 LI Haijiao;WANG Jiajun;HAN Xiping;TAO Qi;ZHANG Shilong(China Railway 19th Bureau Group Sixth Engineering Co.,Ltd.,Wuxi 214028,China;Jiangsu Construction Enterprise Technology Center,Wuxi 214028,China;Jiangsu Prefabricated Building Green Smart Manufacturing and Construction Technology Research Center,Wuxi 214028,China;Department of Road,Bridge and River Crossing Engineering,Huaiyin Institute of Technology,Huai’an 223003,China)

机构地区：[1]中铁十九局集团第六工程有限公司,无锡214028 [2]江苏省建筑业企业技术中心,无锡214028 [3]江苏省装配式建筑绿色智慧制造及施工工程技术研究中心,无锡214028 [4]淮阴工学院道路桥梁与渡河工程系,淮安223003

出　　处：《硅酸盐通报》2023年第8期2856-2864,共9页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金(51808248,51704144);中铁十九局集团科技发展计划(22-B06)。

摘　　要：为研究纤维增强轻骨料混凝土抗疲劳性能,开展了恒应力循环压缩试验,对疲劳应力-应变响应进行了研究。试验采用质量分数为20%的粉煤灰和50%的粒化高炉矿渣部分替代水泥,变量为单掺或混掺不同掺量的钢纤维和聚乙烯醇(PVA)纤维。结果表明:随着循环加载次数的增加,钢纤维混凝土的宏观裂纹数量比PVA纤维混凝土多,试件的破坏形态表现为轻骨料的破裂和纤维的渐进拔出(钢纤维)或断裂(PVA纤维);钢纤维混凝土的疲劳应变及残余应变均最大,而混杂纤维混凝土的最小;在同一应力水平下,混杂纤维混凝土的疲劳寿命最长,而钢纤维混凝土的最短;钢纤维混凝土的极限疲劳损伤高于PVA纤维混凝土和混杂纤维混凝土,且随最大应力水平的降低,该差异逐渐缩小。To study the fatigue resistance of fiber reinforced lightweight aggregate concrete,constant stress cyclic compression tests were conducted to investigate the fatigue stress-strain response.The experiment used 20%(mass fraction)fly ash and 50%(mass fraction)granulated blast furnace slag to partially replace cement,and the experimental variables were single or mixed with different amounts of steel fibers and PVA fibers.The results show that with the increase of number of cycles loading,the number of macroscopic cracks in steel fiber reinforced concrete is more than that in PVA fiber reinforced concrete.The failure modes of specimens are manifested as the rupture of lightweight aggregate and the gradual extraction(steel fibers)or fracture(PVA fibers)of fibers.Steel fiber reinforced concrete has the highest fatigue strain and residual strain,while hybrid fiber concrete has the lowest.At the same stress level,hybrid fiber concrete has the longest fatigue life,while steel fiber concrete has the shortest.The ultimate fatigue damage of steel fiber concrete is higher than that of PVA fiber concrete and hybrid fiber concrete,and the difference gradually decreases with the decrease of maximum stress level.

关 键 词：轻骨料混凝土 粉煤灰 高炉矿渣 钢纤维 PVA纤维 抗疲劳性能 疲劳寿命 

分 类 号：U213.1[交通运输工程—道路与铁道工程]