how are you : Stage 1: (initial stage) in the analytical procedures . In the initial stage, a linearly increasing axial force up to the service axial load (PL) is imposed on the column prior to the blast loads to simulate the gravity load effects presented in the column. The time duration for increasing the loads from zero to full service load is 50 ms. This axial force must be applied gradually in an explicit dynamic analysis. The initial axial load applied to the column is dependent on the service axial load index (ALI) which is expressed as follows: how to do that ?
