Stability Analysis and Comparison of Conventional Concrete and Expanded Polystyrene Concrete Spherical Shells

The main purpose of this study is to investigate the buckling behavior of a light weight expanded polystyrene concrete (EPSC) spherical shell and compare it to an equivalent concrete shell. Such behavior of EPSC is not yet studied and the material has not been implemented in shell structures. The methods adopted are numerical linear buckling analysis (LBA), material non-linear analysis (MNA) and Geometric and material non-linear analysis with imperfection (GMNIA) for both concrete and EPSC spherical shells of the same geometric parameters in ABAQUS software. From the results of the study, the elastic and plastic buckling capacities of EPSC shell and the buckling resistance obtained from GMNIA method are smaller than that of equivalent concrete shell. The maximum displacements of the EPSC shell corresponding to the GMNIA method, with the application of first eigen and actual loads are greater than the concrete shell by small millimeters. Buckling capacities of EPSC shell obtained from the three methods exceed the actual external uniform pressure (self-weight of EPSC and actual snow load), and the displacement results are reasonable enough to ensure that EPSC spherical shells are stable and could be practically applicable.