Properties of High Performance Lightweight Concrete Sandwich Panels Using Local Additives


The main aim of this investigation is to produce high performance lightweight concretesandwich panels consisting of two layers of mortar having different mesh reinforcementand feeded polystyrene concrete core in between. Locally pozzolanic material (ultra –fine feldspar) is used to produce the high performance mortar as partial replacement ofcement. The effect of various factors such as core thickness, volume fraction and type ofreinforcement (polyimide grids, polypropylene meshes and chicken wire meshes) hasbeen investigated. The work covers the physical properties of the mortar and polystyreneconcrete core. Also the structural properties and behaviour of eight series of 1000mmlength and 200mm width concrete sandwich panels with two reinforced mortar faces of20 mm in thickness and core of 30 and 50mm in thickness from polystyrene concretewere investigated by nondestructive and destructive methods.The nondestructive tests included the density and dynamic modulus for mortar andpolystyrene concrete. Also the density and dynamic properties of the concrete sandwichpanels as a whole (dynamic modulus of elasticity, Poisson’s ratio and stiffness constant)were determined by ultrasonic pulse velocity. Flexural properties such as, first crack andultimate loads, moment capacity, modulus of rupture, resilience, ductility and toughnessof the concrete sandwich panels were investigated from the destructive tests .The results show that the ultimate moment increases as the core thickness and thevolume fraction of different types of reinforcement increase and the modulus of ruptureincreases as volume fraction of reinforcement increase. Also it was shown that concretesandwich panels with high toughness and ductility can be obtained by using polyimidegrids or polypropylene meshes to reinforce the compression and tension faces of thepanels.