Dynamic response of multi-layer steel cylinder under internal intense blast loading

In order to evaluate the protective effect and analyze the dynamic response of multi-layer steel cylinder under internal blast loading, we have conducted four experiments, with three different charge mass, ranging from 8.90 to 18.18 kg. The multi-layer steel cylinder we used is composed of 4 layers made of Q345 steel. The 4 layers altogether are 50 mm in thickness, with the 3 inner ones as 10 mm and the outer one as 20 mm respectively. The diameter of the innermost layer is 800 mm and the distance between layers is 5 mm. At the section of charge center and 20 cm axial distance from the charge, the hoop strain and axial strain are measured by eight strain gauges set on the outside of steel shell. Under the blast loading, the plastic deformation occurred locally at the charge center, and the largest deformation appeared at the innermost layer. However, even in the circumstance of the largest charge mass, there is no failure. It is concluded that the thickness of the steel cylinder could be predicted accurately with the energy absorbing design method applied to the unit section of the charge center of the multi-layer steel cylinder. With a proper change in charge mass, the peak hoop strain can reduce to about 1/2 of the section at the charge center, when the axial distance is beyond the 1/4 diameter of the inner layer.