Experimental and Numerical Investigations of Hybrid-Fibre Engineered Cementitious Composite Panels Under Contact Explosions

In this study, the blast response of hybrid-fibre engineered cementitious composite (HFECC) panels with 1.75% polyvinyl alcohol and 0.58% steel fibres (by volume) is experimentally and numerically evaluated for the first time. For blast testing, HFECC and normal reinforced concrete (NRC) panels were tested under contact explosions generated by Plastic Explosive 4 (PE4) on a demolition range. The crater diameter, spalling diameter and fragment size were measured and compared. The experimental results indicate that the crater and spalling diameters of the NRC panels are much greater than those of the HFECC panels. An effective finite element model was also developed to reproduce the responses of the HFECC and NRC panels under blast loads. In the numerical model, a dynamic increase factor formula newly developed by the authors was incorporated to describe the rate sensitivity of HFECC in tension. A particle-based approach was employed, for the first time, to explicitly model the blast load applied on the concrete panels. The efficiency and accuracy of the numerical model are validated by comparing the numerical prediction with the experimental data. The validated model was then used to explore the blast resistance of a reinforced HFECC panel