Compressive behavior of RC short columns strengthened with high-strength stainless steel wire strand mesh and ECC

Based on the research of the mechanical property of the new composite material “high strength stainless steel wire mesh reinforced engineered cementitious composite (ECC) (referred to as HSME)” and compression performance of confined concrete with this material, the compressive behavior of reinforced concrete (RC) short columns strengthened with high strength stainless steel wire mesh reinforced ECC was studied. The test parameters contained the reinforcement ratio and concrete strength of RC short columns, the ECC strength of reinforcement layer and the reinforcement ratio of transverse steel strands. The results indicate that, compared with the unstrengthened RC short columns, the specimens of HSME-strengthened RC short columns not only greatly increase the bearing capacity, but also crack without breaking when they are damaged, exhibiting obvious ductile failure pattern. Meanwhile, the cracking load, peak load and peak displacement are significantly increased. When the applied load reaches about 80% of the peak load and peak load, the maximum crack widths on the surface of the specimen are only 0.09 mm and 0.25 mm, respectively, showing excellent multi-slit cracking ability and crack control capabilities. The load-displacement curve of the HSME-strengthened RC short column is drawn as a skewed single-peak curve, which includes four stages: Elasticity, crack development, maximum load and bearing capacity decline. With the increasing of ECC compressive strength and transverse stainless steel strands reinforcement ratio, the cracking load and peak load of HSME strengthened columns increase significantly. Increasing the reinforcement ratio and concrete strength of the RC column could increase the peak load and the ductility of the HSME strengthened column.