Blast mitigation performance of a novel cladding–connector​ system

A novel cladding–connector system with excellent energy absorption capacity was proposed to protect vulnerable walls in frame structures subjected to blast load in the present study. The cladding–connector system was constructed by combining a sacrificial cladding consisting of an aluminum foam core sandwiched by two steel plates and four connectors made of corrugated steel tubes. On one hand, the cladding absorbed a considerable amount of blast energy. On the other hand, the connectors controlled the load transfer to the protected structure to certain specific pre-defined value. With this approach, both relatively high energy absorption and relatively low load transfer can be achieved simultaneously. Specifically, based on the quasi-static compression test on the connectors and the field blast test on the sacrificial cladding, the numerical model of the proposed system was established with ANSYS/LS-DYNA and validated with the test results. Then the deformation mode, energy dissipation, and load transfer of the cladding–connector systems with flexible or rigid connectors under various charge weights were numerically studied and compared. Results showed that the proposed cladding–connector​ systems could dissipate a considerable amount of energy under blast, in which the major part was dissipated by the cladding and the rest by the connectors. Particularly, compared to the cladding–connector system with rigid connectors, the cladding–connector system with flexible connectors exhibited superior performance in terms of energy absorption and load transfer, especially under intense blast. With the merits of excellent energy absorption, significant blast intensity reduction, and load shift from the vulnerable walls to the load-bearing components, the proposed cladding–connector system with flexible connectors was more promising to effectively protect the existing frame structures against blast.