纤维掺量对聚乙烯醇纤维增强水泥基复合材料动态压缩性能的影响  

Influence of fiber volume fraction on dynamic compressive properties of polyvinyl alcohol fiber reinforced cementitious composites

作　　者：谢磊 李庆华[1] 徐世烺[1] XIE Lei;LI Qinghua;XU Shilang(College of Civil Engineering and Architecture,Zhejiang University,Hangzhou 310058,China)

机构地区：[1]浙江大学建筑工程学院,杭州310058

出　　处：《复合材料学报》2021年第9期3086-3100,共15页Acta Materiae Compositae Sinica

基　　金：国家自然科学基金优秀青年科学基金项目(51622811)。

摘　　要：为探究超高韧性水泥基复合材料(UHTCC)的动态本构关系及纤维体积掺量对聚乙烯醇纤维增强水泥基复合材料(PVAFRCC)动态力学性能的影响,基于Φ80 mm霍普金森压杆(SHPB)装置分别对不同纤维体积分数(Ovol%、0.5vol%、1vol%、1.5vol%、2vol%)的PVAFRCC试件进行冲击压缩试验,得到各类型材料在不同应变率下的应力-应变曲线。结果表明:在约110~270 s-1的应变率范围内,与纤维掺量0vol%的基体(PVAFRCC-0)相比PVA纤维的掺入对动态强度增强因子(μDIF)、冲击韧性和抗破碎能力有明显提高作用,并随纤维掺量的增加而进一步增强;掺2vol%PVA纤维UHTCC(即PVAFRCC-2)试件的μDIF和冲击韧性与基体相比分别提高了约33%~37%和27%~33%,其破碎产物的平均粒径是基体破碎产物的5.9~6.8倍。基于Weibull分布理论提出了适用于掺2vol%PVA纤维UHTCC试件的动态压缩本构模型。In order to explore the dynamic constitutive relationship of ultra-high toughness cementitious composites(UHTCC) and the influence of fiber volume fraction on dynamic mechanical properties of polyvinyl alcohol(PVA) reinforced cementitious composites(PVAFRCC),the compressive impact tests were carried out on PVAFRCC specimens with different fiber volume fractions(0 vol%,0.5 vol%,1 vol%,1.5 vol%,2 vol%) by using Φ80 mm split Hopkinson pressure bar(SHPB) system,through which the stress-strain curves of various types of materials at different strain rates were obtained.The results show that:compared with the matrix without fiber added(PVAFRCC-0),the incorporation of PVA fiber has a significant effect on the dynamic increase factor(μDIF), impact toughness and crushing resistance capacity when the strain rates range from between 100-270 s-1,which will be further enhanced with the increase of fiber volume fraction.The impact toughness is more sensitive to strain rate than to fiber volume fraction.Compared with the matrix,the μDIF and impact toughness increase by nearly 33%-37% and 27%-33% respectively when the fiber volume fraction equals 2 vol%(PVAFRCC-2),and the average fragments size of PVAFRCC-2 also increases to 5.9~6.8 times of that of the matrix.On the basis of Weibull distribution theory,the dynamic constitutive model suitable for UHTCC specimens with 2 vol% PVA fiber volume fraction was proposed and verified.

关 键 词：超高韧性水泥基复合材料 聚乙烯醇纤维 纤维掺量 冲击压缩 WEIBULL分布 

分 类 号：TU528.572[建筑科学—建筑技术科学]