Dynamic model for RC members impacted by metal/PWG composite impact module

The blast simulator based on high-speed impact has the advantages of low cost, strong repeatability and easy data acquisition, and is expected to become a promising supplement to traditional blast tests. However, there is a lack of theoretical model describing the dynamic response of impact system to guide the setting of loading conditions and the evaluation of loading effects. This study focuses on the impact system of a metal/PWG composite impact module (MPCIM) impacting reinforced concrete (RC) beam, aims to develop an accurate dynamic model based on equivalent degree of freedom model for rapid prediction of the impact load and structural response of RC beam. Firstly, regardless of the influence of the impacted structure, the quasi-static and dynamic compression numerical simulations for PWG with different dimensions were carried out. The nonlinear dynamic response model of PWG considering the dimension and impact velocity of MPCIM was developed by combining machine learning methods. Then, based on Euler-Bernoulli beam theory and the impact process of MPCIM and RC beam, a resistance function of RC beam incorporating the dimension of MPCIM was derived. Finally, a novel dynamic model of the impact system that considers the characteristics of the RC beam, the MPCIM dimension, and the dynamic response of PWG was established and verified by numerical simulation results. The results show that the model can accurately predict the impact load and structural response of RC beam impacted by MPCIM.