木纤维对UHTCC干缩性能影响研究  

STUDY ON THE INFLUENCE OF WOOD FIBERS ON THE DRYING SHRINKAGE PERFORMANCE OF ULTRA-HIGH TOUGHNESS CEMENTITIOUS COMPOSITES

作　　者：丁杰[1] 董方园 李庆华[1] DING Jie;DONG Fangyuan;LI Qinghua(Institute of Advanced Engineering Structures,Zhejiang University,Hangzhou 310058,China)

机构地区：[1]浙江大学高性能结构研究所,杭州310058

出　　处：《低温建筑技术》2023年第7期60-64,共5页Low Temperature Architecture Technology

摘　　要：为改善超高韧性水泥基复合材料(UHTCC)的干缩性能,选用未改性与硅烷改性木纤维和PVA纤维混杂作为UHTCC增强体,研究了两种木纤维掺量对UHTCC干缩性能的影响,并结合X射线断层扫描(XCT)和扫描电镜(SEM)对其微观孔隙结构进行分析。结果表明掺入1%、2%和3%硅烷改性木纤维的UHTCC在90d的干缩变形比未掺木纤维的UHTCC分别减小了4.76%、9.62%和11.62%。掺入木纤维会减小UHTCC的干缩变形,高掺量木纤维对UHTCC干缩变形的减小速度会变慢。同掺量硅烷改性木纤维UHTCC的干缩变形均要小于未改性组,硅烷改性可有效提升木纤维与基体的粘结强度。Unmodified,silane modified wood fibers,and PVA fibers are selected as reinforcements to improve the dry shrinkage performance of ultra-high toughness cementitious composites(UHTCC).The effectiveness of two kinds of wood fiber additions on the drying shrinkage performance of UHTCC is studied,in which microscopic pore structure is analyzed by XCT and SEM methods.The results show that the dry shrinkage deformation of UHTCC doped with 1%,2%,and 3%silane modified wood fibers at 90 days was reduced by 4.76%,9.62%,and 11.62%,re⁃spectively,comparing with UHTCC without wood fibers.Wood fibers reduce the drying shrinkage deformation of UHTCC,while high content of wood fiber can slow down the drying shrinkage deformation of UHTCC.The drying shrinkage deformation of silane modified wood fiber UHTCC with the same content is smaller than that of the unmodified group.Silane modification effectively improves the bond strength between wood fibers and the matrix.

关 键 词：超高韧性水泥基复合材料 木纤维 硅烷改性 干燥收缩性能 

分 类 号：TU531.13[建筑科学—建筑技术科学]