Experimental investigation blast resistance of CFRP/polyurea composite plates under blast loading

With the development of composite structures, polyurea elastomer can be utilized to enhance the protective performance of composite laminated structures under blast or impact loading. Three types of polyurea coated CFRP (CFRP/polyurea) composite plates were experimentally evaluated. In order to study the blast resistance of CFRP/polyurea composite plates subjected to free air blast loading, a three-dimensional digital image correlation (3D-DIC) full-field measurement method was used to obtain the dynamic response of composite structures. The effect of polyurea coating position and scaled distance were analyzed and discussed. In addition, the failure modes and failure mechanisms of CFRP/polyurea composite plates were analyzed. The results show that 3D-DIC technique is a good tool for the assessment of the dynamic response of CFRP/polyurea composite plates under blast loading. From the deformation and damage level of structures, the polyurea coating on rear surface of CFRP exhibited superior blast resistance. With the decrease of scaled distance, the deformation level of CFRP/polyurea composite plates increases. The failure modes of CFRP/polyurea composite plates varied significantly with the change of structural types. Brittle fracture, structural warpage and delamination are the main failure modes of CFRP materials. Moreover, cracking, melting and the deformation of the micropore are the main failure mechanism of polyurea coating. Overall, the combination of CFRP plate and polyurea has an obvious role in the aspect of blast resistance.