混杂纤维增强应变硬化水泥基复合材料的弯曲性能研究  

Study on Bending Properties of Hybrid Fiber Reinforced Strain HardeningCementitious Composites

作　　者：于海洋 李地红 代函函 高群 YU Haiyang;LI Dihong;DAI Hanhan;GAO Qun(College of Civil and Transportation Engineering,Beijing University of Civil Engineering and Architecture,Beijing 100044,China)

机构地区：[1]北京建筑大学土木与交通工程学院,北京100044

出　　处：《材料导报》2020年第S01期229-233,共5页Materials Reports

基　　金：北京建筑大学研究生创新项目。

摘　　要：本工作研究了聚乙烯醇-玄武岩纤维混杂应变硬化水泥基复合材料(PB-SHCC)的弯曲性能。水泥基体材料水胶比为0.25,混杂体系中聚乙烯醇纤维分别为体积含量的1.5%和1.7%,再混杂一定体积含量的玄武岩纤维,制备成聚乙烯醇-玄武岩纤维混杂应变硬化水泥基复合材料,标准养护28 d后对该复合材料进行三点弯曲试验。结果表明,PB-SHCC具有弯曲应变硬化的特性,弯曲挠度较单掺体系会有所削弱,但削弱程度不大,仍具有较高的延性;玄武岩纤维的掺量在0.1%~0.3%以及0.8%~1.0%时,均利于复合材料的初裂强度及抗弯强度的提高。此外,本工作基于ASTM C1018和JSCE-SF4标准,改进并定义了弯曲韧性指数和弯曲韧性因子,能够简洁有效地评价SHCC材料的弯曲韧性,且两类指标吻合性较好。The bending properties of polyvinyl alcohol-basalt fiber hybrid strain hardening cementitious composites(PB-SHCC)were studied in this paper.The water-binder ratio of cement matrix material was 0.25,the volume content of polyvinyl alcohol fiber in the hybrid system was 1.5%and 1.7%respectively,and then mixed with a certain volume content of basalt fiber to prepare polyvinyl alcohol-basalt fiber hybrid strain hardening cement matrix composites.A three-point bending test was carried out after standard curing for 28 d of the PB-SHCC.The test results show that PB-SHCC has the characteristics of bending strain hardening,and the bending deflection will be weakened compared with the single blending system,but the weakening degree is not great,and it still has high ductility;when the content of basalt fiber is 0.1%—0.3%and 0.8%—1.0%,it is beneficial to the improvement of initial crack strength and bending strength of the composites.In the evaluation of bending toughness,based on ASTM C1018 and JSCE-SF4 standards,the bending toughness index and bending toughness factor are improved and defined,which can succinctly and effectively evaluate the bending toughness of SHCC materials.The two indexes have a good agreement.

关 键 词：聚乙烯醇纤维 玄武岩纤维 纤维混杂 应变硬化水泥基复合材料 三点弯曲 弯曲韧性 

分 类 号：TB332[一般工业技术—材料科学与工程]