Analytical and experimental assessment of household extruded polystyrene foam (XPS) practicability for sandwich hull panels of small craft

Object and purpose of research. This paper is an integrated study of extruded polystyrene foam (XPS) practicability for three-layered composite hull structures of small craft. Subject matter and methods. Mechanical properties of composite materials and their components are determined experimentally (three-point bending, longitudinal tension/compression). Elastic properties and limit-state characteristics are obtained from beam theory, mixed model of composite beam, finite-element method, as well as solution of geometrically non-linear contact problems as per Newton-Raphson iterative technique. Main results. The study illustrates final diagrams for structural responses of investigated composite beam, filler and binder as functions of pre-defined displacement of test rigging. It also gives the estimates for equivalent Young’s moduli, as well as preliminary positive opinion about the practicability of XPS as a substitute for the conventional wood veneer in composite structures of small ships. The paper also presents a structurally similar FE model suitable for prediction calculations of large complex structures that can be tested only when the whole full-scale hull is available. Conclusion. This study formulates and solves the elastic problem for the investigated XPS-based sandwich panels. The results give an idea about the practicability of this material for shipbuilding applications.