###### Abstract  
This paper presents a study on the dynamic behavior of thin aluminum plates subjected to consecutive fragment impact and blast loading. To this end, two separate experimental setups are used. In the first setup, 2 mm thick aluminum plates \(EN\)_-\(AW\)_-1050A-H24 were subjected to the ballistic impact of fragment-simulating projectiles (FSPs). Experiments were carried out for FSP calibers of 7.62 mm and 12.7 mm considering both single impact and triple impacts with variations in the spacing of the impact locations. The out-of-plane displacement and in-plane strain fields were measured using digital image correlation (DIC) coupled to a pair of high-speed cameras in a stereoscopic setup. In the second setup, a subsequent blast loading was applied to the perforated plates using an explosive-driven shock tube (EDST). After the plates are perforated, the strain field around the holes depended on the caliber, the impact orientation of the FSP, and the distance between the impact locations. When the blast loading was applied, cracks tended to appear in areas of strain concentration between the perforated holes. It was found that the relative distance between the holes significantly influences the target's response mode. combined fragment impact and blast loading; blast loading; fragment impact; digital image correlation; fragment-simulating projectile; explosive-driven shock tube; crack propagation Article  
Dynamic Behavior of Aluminum Plates Subjected to Sequential Fragment Impact and Fragment Impact and Blast Loading: An Experimental Study  
1 Mechanics of Materials and Constructions Department, Vrije Universiteit Brussel (VUB), Pleinlaan 2, 1050 Brussels, Belgium; [EMAIL_ADDRESS] (O.A. ); [EMAIL_ADDRESS] (L.P)  
2 Civil and Materials Engineering Department, Royal Military Academy, Avenue de la Renaissance 30, 1000 Brussels, Belgium; [EMAIL_ADDRESS] (A.A.); [EMAIL_ADDRESS] (B.B.) 3 Defense Science and Technology, Civil Engineering Department, Military Research Center,  
Ministry of National Defense, Nabeul 8021, Tunisia; [EMAIL_ADDRESS]  
4 Civil and Materials Engineering Department, Royal Military Academy, Avenue de la Renaissance 30, 1000 Brussels, Belgium; [EMAIL_ADDRESS] (A.A.); [EMAIL_ADDRESS] (B.B.) 3 Defense Science and Technology, Civil Engineering Department, Military Research Center,  
Ministry of National Defense, Nabeul 8021, Tunisia; [EMAIL_ADDRESS]  
the literature regarding the combined effect of blast and fragment impact loading on protective structures is rather scarce. Over the past few years, scenarios where the fragment impact occurs before the blast wave have received increased interest. It is found that in such cases, the target undergoes the highest damage [10]. This can be explained by the reduced structural integrity of the protective barrier after exposure to the fragment impacts. The latter creates defects and weak points, facilitating fracture initiation when blast loading is applied. Researchers and practitioners have tried to establish reliable and controlled experiments to improve the fundamental understanding of the combined effect of blast loading and fragment impact on materials and structures. [PERSON] et al. [11] investigated the blast response of pre-damaged laminate glass plates caused by ballistic impact perforation. They experimentally proved that the protective capability of the laminated glass is clearly reduced if it is pre-damaged by a fragment. [PERSON] et al. [12] experimentally investigated the dynamic behavior of a multi-layered panel under combined blast and fragment impact loading. The results showed that when fragments impact the front surface of the panel before the blast wave, they initiate failure mechanisms on the rest of the panels aggravating the final damage caused to the structure. The same conclusions were supported by a more recent work by [PERSON] et al. [13].