Anisotropic dynamic theory to predict blast responses of composite fluted-core sandwich protective door panels

A dynamic theory of simply supported orthotropic pultruded glass fiber reinforce plastic (GFRP) fluted-core sandwich panels under blast loading was proposed based on the first order shear theory, and the analytical solution was given based on the mode superposition method. The displacement curves predicted by the theory are consistent with finite element modeling (FEM) results. Based on the theory, multi-failure criteria of the fluted-core sandwich panel were proposed to reveal the competition between the facesheet failure and the core shear failure. A new type of composite protective door was assembled from GFRP fluted-core sandwich panels and steel frames. Explosion experiments were carried out and the test displacements and strains were compared with theoretical predictions considering damping. The peak blast pressure the door panel could sustain was predicted by multifailure criteria. The theory is effective in predicting the elastic dynamic response and failure pressure of the GFRP fluted-core sandwich panel. The composite door has little damage when the scaled distance is larger than 1.494 m/kg1/3. With weight of only 111.4 kg and excellent performance under blast loading, the GFRP fluted-core sandwich is a good choice for protective doors.

Automated summary

A dynamic theory based on the first order shear theory was proposed for predicting the response and failure pressure of GFRP fluted-core sandwich panels under blast loading. Experimental and theoretical predictions were used to verify the protective performance and practicality of the composite door.