Compressive Performance of RC Columns Strengthened with High-Strength Stainless Steel Wire Mesh-ECC under Small Eccentric Compression Load

Abstract

In this research, a novel composite material, high-strength stainless steel wire mesh-ECC, is proposed and designed to strengthen RC columns. The small eccentric compressive performance of RC columns strengthened with high-strength stainless steel wire mesh-ECC was investigated through compression tests and compared with unstrengthened columns and RC columns strengthened with ECC. Six columns were designed and tested, and the test parameters contained different strengthened methods, eccentricity ratios, and reinforcement ratios of longitudinal high-strength stainless steel strand. The failure patterns, load-carrying capacity, strain of concrete/ECC and reinforcement, etc., were analyzed based on the test results. The high performance of the high-strength stainless steel wire mesh-ECC and the advantages of the proposed strengthened method, including good ductility, excellent crack-control ability and satisfactory failure patterns, were demonstrated when compared with the specimens strengthened with ECC. The stainless steel wire mesh-ECC-reinforced layer can have effective constraint columns and can control the crack ability. The cracking load of the stainless steel wire mesh-ECC-reinforced column is 100.0–113.3% higher than that of the unreinforced column, and the peaking load is 99.8–108.0% higher than that of the unreinforced column. The stainless steel wire mesh-ECC-reinforced column shows good ductile failure characteristics, and compared with the unreinforced column, the ductility is increased by 75.6–77.8%. Based on the analysis of the strain distribution and failure patterns, the mechanical mechanism of RC columns strengthened with the novel composite material high-strength stainless steel wire mesh-ECC is proposed.