Evaluation of failure probability for RC slabs subjected to low-velocity impacts

Abstract

This study presents a procedure to evaluate the failure probabilities of reinforced-concrete (RC) slabs subjected to low-velocity impacts considering the uncertainties existing in slab features and impactor properties. A two-degree-of-freedom (2-DoF) non-linear model using a dynamic load-displacement curve is adopted to simulate the impact response of RC slabs because of its accuracy and efficiency. This model can effectively consider punching shear behaviour, which dominates the response of most RC slabs under impact loading. The 2-DoF is coupled with a correlation-controlled Latin hypercube sampling method to assess the failure probability. A sensitivity analysis is performed to identify significant random variables and a comprehensive parametric study is conducted to investigate the effect of different parameters in slab design and impactor properties on the failure probability of the impacted slab. The failure probabilities were found to fit a normal distribution under different impact velocities. This result is used in a simple procedure to derive the impact-induced failure probability curves with the distribution means estimated at the mean parameters, and the coefficients of variation ranged between 0·15 and 0·20.