Rear-surface collapse perforation of concrete targets under buried explosion

Experimental research on collapse and perforation failure at the rear surface of a concrete target induced by buried explosion of a cylindrical explosive charge was performed. The aim is to develop an available approach to predict the critical collapse thickness under explosion loading. It is found that both the diameter and the length-to-diameter ratio of the cylindrical explosive charges have remarkable influence on the critical collapse thickness. Based on the experimental data for the plain concrete with the compressive strength of 35 MPa, an analytical expression for the relation between the dimensionless critical collapse thickness on concrete target and the length-to-diameter ratio of explosive charge is developed via dimensional analysis. Moreover, it is also found that there exists an incomplete similarity of the critical collapse thickness in the diameter of explosive charge, although the complete similarity in the length-to-diameter ratio alone cannot be established.