PVA纤维增强水泥基复合材料高温性能研究  

High Temperature Performance of Cementitious Composites Reinforced with PVA Fibers

作　　者：李丹[1] 何锐[1] 王帅[1] 王锴[1] 盛燕萍[1] 

机构地区：[1]长安大学材料科学与工程学院,西安710061

出　　处：《硅酸盐通报》2015年第6期1604-1610,共7页Bulletin of the Chinese Ceramic Society

基　　金：高等学校博士学科点专项科研基金博导类资助课题(20130205110013);中国博士后科学基金项目(2014M552397;2013M532005);青海省重大科技专项计划项目(2014-GX-A2A);长安大学中央高校基本科研业务费专项资金资助(2013G3312018;2014G1311081)

摘　　要：对PVA纤维增强水泥基复合材料的高温性能进行研究,分别测试了该材料在经受不同高温后的质量损失、抗压强度以及弯曲韧性,并对其微观结构变化进行了分析。结果表明,相比于普通水泥基材料,PVA纤维增强水泥基复合材料的抗压强度高,变形能力大,抗折强度高,弯曲韧性优越,其中纤维掺量为2%的试块28 d抗压强度达到45.98 MPa,抗折强度可达到14.10 MPa,最大挠度达到0.68 mm;高温处理后掺有PVA纤维的试块完整性良好,没有出现破坏性断裂,只表现为微小裂纹;随着温度的升高,不同纤维掺量砂浆试块的质量损失增大,抗压强度和抗折强度以一定的速率下降,但在800℃高温处理后试块仍具有一定的抗压强度和弯曲韧性,纤维掺量为2%的试块的抗压强度能达到18.9 MPa,最大挠度可保持在0.12 mm;根据微观测试可以看出,随着温度的升高,纤维缓慢熔出使试块内部出现相互交错的孔隙通道可有效防止试块高温爆裂,试块内部结构由致密变为松散蜂窝状。The high temperature performance of cementitious composition reinforced with PVA fibers was researched in this paper. Then a detailed analysis was made to the mass loss, compressive strength, flexural toughness and microscopic structure of materials after being subjected to different high temperatures. Studies shown that, compared with ordinary cementitious composition, eementitious composites reinforced with PVA fibers had greater compressive strength, higher flexural strength and superior flexural toughness after high temperature treatment. Among them, the compressive strength of the test block which with the fiber content of 2% can up to 45.98 MPa, the flexural strength can up to 14. l0 MPa, the maximum deflection can be maintained at 0.68 ram. The test block showed excellent integrity with only slight cracks instead of any destructive fracture. With the increase of temperature, the mass loss increase, tile flexural strength and compressive strength decrease at a certain rate. However, the test block still had some compressive strength and flexural toughness after high temperature treatment of 800 ℃. The compressive strength which with the fiber content of 2% can be 18.9 MPa, the maximum deflection can be maintained at 0. 12 ram. As can be seen from the microstructure, with the increase of temperature, fibers melt out slowly, pore channels appeared in the test block which can prevent the burst effectively. The test block structure changed from dense to loose

关 键 词：聚乙烯醇纤维 抗压强度 抗折强度 弯曲韧性 高温性能 

分 类 号：TU525[建筑科学—建筑技术科学]