ECC面层加固空斗墙抗震性能试验研究

Experimental investigation on seismic behavior of cavity wall strengthened with ECC splint

高延性纤维增强水泥基复合材料(ECC)具有高强度、高延性和水硬过程中粘结性能良好,在砌体加固工程中具有广泛的应用前景。通过对2片未加固、2片单面和2片双面ECC面层加固后空斗墙进行水平拟静力试验,对比加固不同砌法下单面和双面空斗墙破坏模式、滞回曲线、刚度退化、承载能力和延性性能,进而研究ECC面层加固对墙体抗震性能的影响。利用ABAQUS有限元软件,采用预留孔洞的整体建模方式进行有限元分析,对比了试验值与计算值。结果表明:ECC面层与砖墙之间粘结较可靠,ECC面层优越的材料抗力可以抵抗墙体承担的水平剪力;单、双面ECC面层加固后空斗墙体极限变形能力及极限承载力均得到大幅提升,试件延性和抗震性能同步改善;有限元计算的水平承载力值与试验值相差不大。

With high strength, ductility and good bonding properties during the cement hydration process, high ductility fiber reinforced engineered cementitious composites(ECC) have a wide application prospect in masonry reinforcement engineering. The tests of two unreinforced cavity walls, two strengthening specimens with single ECC splint and two strengthening specimens with double ECC splints were conducted under in-plane cyclic loading. After the comparison of the failure mode, hysteretic curve, stiffness degradation, bearing capacity, and ductility of the single and double ECC splints strengthened cavity walls were analyzed to investigate seismic performance of strengthening ECC splint. The ABAQUS software was used to verify the test by comparing the experimental values and calculated values. The results show that the bonding properties between the ECC splint and the cavity wall are reliable, which illustrates that the superior material resistance can resist horizontal shear loads on cavity walls. The ultimate deformation and load bearing capacities of the single/double ECC splint strengthened cavity walls are largely improved, and the ductility and seismic performance of the strengthened specimens are also improved. The calculated horizontal shearing loads by the finite element analysis is almost matched with the experimental values.