Flexural and shear behaviour of precast sandwich slabs comprising thin walled steel fibre reinforced self-compacting concrete

Abstract

Insulated sandwich panels are often composed of external concrete layers, mechanically connected through metallic elements, such as trusses. Due to their high thermal conductivity, metallic connectors tend to cause thermal bridges on the building envelope. In view of this problem, an innovative solution for sandwich slabs is proposed within the framework of a pre-fabricated modular housing system. The referred slabs are based on a sandwich solution composed by two thin layers of Steel Fibre Reinforced Self-Compacting Concrete (SFRSCC) that are connected by thin perforated plates of Glass Fibre Reinforced Polymer (GFRP), used together with a thermal insulation core-layer. The bottom concrete layer is reinforced with conventional steel rebars and steel fibres, whereas the upper one does not have conventional reinforcement. This paper presents a preliminary experimental program aiming to assess the flexural and shear behaviour of this type of sandwich panel solution. The obtained results confirm the feasibility of the proposed sandwich slab system, revealing its capacity in terms of load carrying capacity and ductility performance. In addition, the flexural behaviour of the tested specimens was numerically analysed for the serviceability limit states using the finite element method with consideration of the material non-linearity.