The response of circular plates to repeated uniform blast loads: An experimental and numerical study

• Investigation into the response of circular plates to repeated uniform blast loads.
• Large inelastic global deformation with thinning at the clamped boundary and in some cases tearing.
• Increase in Vickers hardness at the boundary and central region with increasing number of blast load.
• Very good correlation is obtained with regards to midpoint deflection and deformation profiles.
• Plastic strain obtained numerically shows good qualitative correlation with the experimental VH.

This paper presents the results of an experimental and numerical investigation into the response of circular Domex-700 MC steel plates to repeated uniform blast loads. The Domex 700 steel tests plates of thickness either 2 or 3 mm are mounted onto a ballistic pendulum and subjected to uniform blast load up to five times for repeated loading. In general, the plates show large inelastic global deformation with thinning occurring at the clamped boundary and in some cases tearing. A trend of increasing permanent mid-point deflection is observed for an increase in charge mass and number of witnessed blast loads. The results also show a decrease in the incremental mid-point deflection and an increase in the Vickers hardness of the plate at the boundary and central region with increasing number of witnessed blast loads. Numerical simulations are carried out to gain further insight into the deformation of plates subjected to repeated blast loading using ABAQUS/Explicit v6.10.1 in conjunction with the inbuilt blast function code, ConWep. A scaling factor is adopted to model the amplified blast wave resulting from the detonation of cylindrical charges at one end of a cylindrical tube. Very good correlation is obtained with regards to midpoint deflection and deformation profiles. The plastic strain obtained numerically shows good qualitative correlation with the experimental Vickers hardness tests.