Behavior of confined concrete columns with HSSSWR meshes reinforced ECC jacket under uniaxial compression

This paper presents experimental and analytical studies on the uniaxial compressive properties and failure mechanics of confined concrete columns with a novel strengthening system, high-strength stainless steel wire rope (HSSSWR) meshes reinforced engineering cementitious composite (ECC) jacket. The effects of the formula of ECC, spacing of lateral HSSSWRs and concrete strength were considered in this experimental study. Test results showed this strengthening system can confine concrete columns effectively due to good bond performance between the jacket and concrete, which changed the concrete failure mode from brittleness to ductile failure and resulted in effective improvements in bearing capacity, deformation capacity, ductility and energy absorption capacity. Multiple fine cracks were observed in the confined concrete columns, which indicated the excellent crack-width controlling ability of the jacket. By embracing path-independence assumption and modifying the relationship of hoop strain and vertical strain for concrete columns confined by HSSSWR meshes reinforced ECC jacket, an analytical model for predicting the load-displacement curve of the HSSSWR meshes reinforced ECC confined concrete columns was developed. The predicted results by using the proposed analytical model were found in good agreement with the experimental results.