Development of pressure-impulse models and residual capacity assessment of RC columns using high fidelity Arbitrary Lagrangian-Eulerian simulation

Pressure-Impulse (P-I) models as graphical representations are frequently adopted to evaluate damage of structures subjected to extreme loads. The main objectives of this research is to derive analytical formulas to propose pressure (P-0) and impulsive (I-0) asymptotes of RC columns at different levels of damages, and to develop P-I models and empirical equations of RC columns for prediction and assessment of blast induced damages using an advanced numerical modeling approach. An innovative technique to predict the residual capacity of RC columns when subjected to detonation events is essential to measure the column axial capacity after blast loads. This study can offer a methodology for a reliable, simple and accurate dynamic analysis to study the residual capacity of columns under blast detonation. Available literature mainly focused on the simulation of explosion loads by using simplified pressure time histories to develop P-I curves and rarely simulated the actual explosive. Therefore, there is a gap in the literature concerning general relation between blast damage of columns with different explosive loading conditions for a reliable and quick evaluation of column behavior subjected to blast loading. In this paper, the Arbitrary Lagrangian Eulerian (ALE) technique is implemented to simulate high fidelity blast pressure propagations. The numerical model is calibrated and validated by comparing the results from blast field tests performed by other researchers. To develop the designated P-I curves, damage assessment criteria are used based on the residual capacity of column. Intensive investigations are implemented to assess the effect of column dimension, concrete and steel properties, reinforcement ratio and axial load index on the P-I diagram of RC columns. The produced P-I models can be applied by designers to predict the damage of new columns and to assess existing columns subjected to different blast load conditions.