Development of insulated FRP-confined Precast Concrete Sandwich panel with side and top confining plates and dry bond

Abstract

Traditional insulated concrete sandwich panels are composed of two concrete wythes separated by a layer of foam insulation, where the wythes are connected by various types of shear connectors. Due to the flexibility of the shear connectors, sandwich panels assume partial degree of composite action, and the strength is typically lower than that of solid panels. Traditionally, more shear connectors or stiffer shear connector are used to improve the performance of the sandwich panels. However, this is a limit using this method. This study proposes a new method to use confined concrete, since it was reported that compressive strength and effective ultimate compressive strain for confined concrete are much higher than un-confined concrete. In particular, this study will develop an insulated FRP-confined Precast Concrete Sandwich (FPCS) panel, where external FRP plates provide a confining effect to improve the performance of FPCS panels. In addition, the external FRP plates can act as water barrier to protect the concrete and meet other requirements, thereby eliminating additional roofing materials. A comprehensive research program has been conducted to study the effect of wet bond vs. dry bond between the FRP and concrete, and top FRP confining plates vs. top and side FRP confining plates, based on extensive tests on scaled and full-scale FPCS panels. This paper studies the panels with side and top FRP confining plates, and dry bond between the FRP and concrete. Bending tests on scaled and full-scale panels were conducted. It can be concluded that the FPCS panels were comparable to solid panels, which can be used for floor and roof constructions.