纤维增强水泥基复合材料加固砌体墙抗剪性能试验研究及破坏机理分析

EXPERIMENTAL RESEARCH AND FAILURE MECHANISM ANALYSIS OF SHEAR BEHAVIORS OF MASONRY WALLS STRENGTHENED BY ECC

将纤维增强水泥基复合材料(ECC)以及1‰聚乙烯醇(PVA)纤维用于砌体墙的砌筑砂浆和抹灰砂浆,设计了不同"抹灰+砌筑"组合的7堵砌体墙,采用对角加载剪切试验,研究了ECC和PVA纤维砂浆对砌体墙抗剪性能、刚度以及延性的提升效果。研究结果表明:相比"普通抹灰砂浆+普通砌筑砂浆"砌体墙,PVA纤维抹灰砂浆使砌体墙抗剪强度提高12%,PVA纤维砌筑砂浆使砌体墙抗剪强度提升42%;而ECC用于抹灰时,抗剪强度比PVA纤维抹灰砂浆提升34%,ECC用于砌筑时,抗剪破坏方式为延性破坏;ECC同时用于抹灰和砌筑时,抗剪强度提升102%,其刚度、延性最大,抗剪和抗震性能最好;以上砌体墙的刚度均较普通砂浆制作的砌体墙有所提升,表现出良好的抵抗变形的能力。

In the paper,engineered cementitious composites(ECC) and 1‰ polyvinyl alcohol(PVA) fiber reinforced mortar were used in masonry mortar and plaster mortar of masonry wall. Seven types of "plaster + masonry" masonry walls were designed for diagonal shear loading test.The paper studied the effect of the shear performance,stiffness and ductility of masonry walls. The research results showed that the shear strength of masonry wall can increased by 12% and 42% with PVA fiber applied to plaster mortar and masonry mortar respectively compared with "ordinary plaster mortar+ordinary masonry mortar"masonry walls.The shear strength of masonry wall can increased by 34% by ECC used in plaster. The failure mode was ductile fracture when ECC used in masonry; the shear strength can increased by 102%. and the shear whose performance and seismic performance of masonry wall were the best with ECC both used in plaster and masonry. Compared with the ordinary masonry wall, the stiffness of the above masonry walls were improved and showed a good capacity to resist deformation.