Air Blast Analysis of the RC Column with Spiral Strip and Steel Tube Cover

In this tutorial, the simulation of an air blast explosion on a reinforced concrete (RC) column with spiral strips and a steel tube cover has been carried out in Abaqus. The concrete column is modeled as a three-dimensional solid part, the spiral strips and longitudinal bars are modeled as wire parts, and the steel tube cover is modeled as a shell part. To capture concrete behavior under blast loading, the Johnson Holmquist-II (JH-2) model is introduced as the constitutive model, allowing the incorporation of damage variables, with parameters often derived from complex or costly experiments. In this example, the JH-2 model is implemented through input file coding for concrete, while the Johnson-Cook hardening and damage model is applied to define steel material behavior under high strain rate conditions. A dynamic explicit step is selected for the analysis, as it is well-suited for problems involving rapidly changing conditions, impacts, or explosive loads. The steel reinforcements are embedded inside the concrete column, perfect contact is assumed between the concrete column and steel tube, and the CONWEP blast method is applied to simulate the blast pressure on the column surface. Proper meshing and boundary conditions are assigned to all parts to ensure accuracy. After the simulation, outputs such as stress, strain, damage, failure, displacement, and related responses are available for evaluation.