Shear Behavior of Lightweight Sandwich Reinforced Concrete Slabs

Abstract

A new lightweight sandwich reinforced concrete (LSRC) section has been developed which is suitable to be used for slab members in reinforced concrete structures. Prefabricated autoclaved aerated concrete (AAC) blocks are used as infill in the slab section where the concrete is considered ineffective under bending. As a result, the flexural capacity of an LSRC section is expected to be the same as equivalent solid section having identical height. The ability to resist shear is however in question as the AAC infill generally has lower strength grade than that of the normal dense concrete. This paper presents a numerical investigation into the behavior of LSRC slabs when shear is critical and the slabs will failure in shear. ANSYS version 12.1 is employed to develop three dimensional nonlinear finite element models of LSRC slabs.The numerical study will be compared with the test results. Some differences in the results were found due to the support modeling. The hinge-hinge support over predicted both the strength and stiffness of the modeled slabs when compared with the tested slabs, while the hinge-roller support condition led to underestimated outcomes. Recommendations for the modeling improvement are made.