掺入短切纤维的纤维编织网增强混凝土薄板弯曲力学性能试验研究  

Experimental study on bending mechanical behavior of textile reinforced concrete thin-plates with short dispersed fibers

作　　者：沈玲华[1,2] 王激扬[1] 徐世烺[1] 

机构地区：[1]浙江大学建筑工程学院,浙江杭州310058 [2]浙江科技学院土木与建筑工程学院,浙江杭州310023

出　　处：《建筑结构学报》2016年第10期98-107,共10页Journal of Building Structures

基　　金："十二五"国家科技支撑计划(2012BAJ13B04)

摘　　要：为研究掺入短切纤维的纤维编织网增强混凝土(简称TRC)薄板的受弯承载能力及裂缝开展,对其进行了四点弯曲试验,对比分析了TRC薄板纤维编织网浸胶的处理、水灰比、短切纤维种类和掺量,以及钢纤维长径比等因素的影响。在此基础上,采用环境扫描电镜及能谱仪对短切纤维与纤维编织网在混凝土基体中的微观形貌进行观察。研究结果表明:对浸胶处理的TRC薄板、掺入碳纤维和聚丙烯纤维的试件的承载力提高幅度分别为16%和32%;掺入钢纤维并未提高薄板的承载力。未浸胶处理的TRC薄板,掺入短切碳纤维、钢纤维、聚丙烯纤维和掺入短切钢纤维与聚丙烯纤维混合纤维的试件,其承载力的提高幅度分别为132%、47%、27%和86%,且钢纤维和碳纤维掺量越多,薄板开裂后刚度越大,但聚丙烯纤维的掺量不宜偏高。短切碳纤维与钢纤维均能有效减缓裂缝的扩展,但在微观裂缝处两种纤维的交联作用机理不同;掺入短切纤维可使薄板裂缝数量增多。The four-point bending tests of textile reinforced concrete（ TRC） thin-plates adding short fibers were performed on the bearing capacity and crack behavior. The influences of different surface treatments of textile,water cement ratio,the types and volume content of short fibers,length-diamond ratio of short steel fiber were investigated.On this basis,microstructure of short fibers and multifiament yarn in the matrix was observed by SEM and EDS. The results show that for TRC thin-plates with impregnated textile,the bearing capacity of thin-plates with short carbon fiber and polypropylene（ PP） fiber increases by 16% and 32%,respectively,but the addition of steel fiber does not contribute to thin-plates＇ bearing capacity. For TRC thin-plates with non-impregnated textile,the capacity of thinplates with short carbon fiber,steel fiber,PP fiber and hybrid fiber increases by 132%,47%,27% and 86%,respectively. The more volume content of short steel and carbon fibers,the higher post cracking strength of the thinplates,but the volume content of PP fiber should not be superabundant. Short carbon fiber and steel fiber can delay the crack extension effectively,but their mechanisms of bridging effect crossing the microcrack are different. The addition of short fibers increases the number of cracks,which could be qualitatively interpreted by the crack spacing theory.

关 键 词：纤维编织网增强混凝土薄板 短切纤维 四点弯曲试验 多重开裂 交联作用 

分 类 号：TU528.572[建筑科学—建筑技术科学] TU375.203