Study on the axial compression behavior of masonry columns strengthened with engineered cementitious composite splints and fiber-reinforced polymer strips

Abstract

This paper presents experimental and analytical studies on the axial compressive properties and failure mechanics of 19 strengthened masonry columns. The masonry column was strengthened singly and compositely by applying engineered cementitious composite (ECC) splints and wrapping discontinuous fiber-reinforced polymer (FRP) strips around the sides of the masonry column. The effects of the type of strengthening material (ECC splints or FRP strips), the thickness of the ECC splint, and the FRP strip strengthening area ratio on the failure mode, peak load, strain behavior, and energy dissipation of the specimens were analyzed and discussed in this experimental study. Under the appropriate parameters, the best strengthening effect was observed for the compositely strengthened masonry columns. In particular, the ductility, bearing capacity, and energy dissipation of masonry columns can be significantly improved by utilizing FRP with lower tensile strength, a higher FRP strip strengthening area ratio and a thicker ECC splint. Based on the existing computational models and code calculation methods for masonry columns strengthened with ECC splints and FRP strips, a formula for calculating the compressive bearing capacity of strengthened masonry columns was derived. The error between all the calculated and the measured results was less than 7.1%.