Computational Simulation and Experimental Characterization of Sandwich Composite Panels Subjected to Blast Loads

摘要

Blast response experimental data along with quasi-static material property datarnwas generated for E-glass and carbon sandwich composite panels with balsa, PVCrnfoam and TYCOR? cores. In this work the Pressure vs Impulse (P-I) curvernmethodology that was developed to represent estimated damage levels in civilrninfrastructure components subjected to blast loadings, is adapted for sandwichrncomposite panels. This enables the generation of a database of performancernenvelopes of sandwich composite panels with a variety of skin and core materialrncombinations under various blast and shock loading scenarios, for naval compositernstructural applications. The P-I diagram (also known as iso-damage curve)rnmathematically relates a specific damage level to a combination of blast pressurernand impulse imposed on a particular structural element, allowing the reduced orderrnmodeling of different composite panel system configurations. Each curve in the P-Irndiagram represents a certain response level, such as mid-span deflection or rotationrnat supports.rnThe strength vs deformation properties of various undamaged sandwichrncomposite panels are established by nonlinear quasi-static finite element analysis ofrnsandwich composite panels subjected to mid-span deformation under displacementrncontrol, with boundary conditions matching that of the experimental blast tests andrnidealized for SDOF (single degree of freedom) modeling. Nonlinear stress-strainrnmaterial data obtained from quasi-static tensile tests of face sheets and compressiverntesting of corresponding core materials is used as input for the material constitutivernmodels. Numerical simulations of reduced order, i.e. equivalent SDOF systemrnmodels of the blast loaded sandwich composite panels are conducted; to enable thernconstruction of iso-damage curves that are suitable for damage prediction over arnwider range of blast pressure and impulse combinations. Results show goodrncorrespondence between model predictions and experimental results for thernperformance evaluation of various sandwich composite panel configurations.