Hydrodynamic Ram Test of Composite T-Joint Structure

The response of composite T-joint specimens to hydrodynamic ram testing is investigated in this study. A hydrodynamic ram is one of the major manmade threats to aircraft structures, particularly to fuel systems, which are the most vulnerable to ballistic battle damage. As composite materials are increasingly being used in aircraft structures, survivability-enhanced structural designs, particularly in composite fuel tanks, have become one of the key elements in aircraft development. Composite bonded/bolted laminate and sandwich specimens are selected and instrumented from the consideration of the joint parts of the aircraft, and a hydrodynamic ram gun simulator is used to propagate the ram pressure toward the specimens. A shorting pin device and a high-speed camera with lighting are used to support the data measurement. A total of nine tests are conducted, and the pressure, strain, deformation data are investigated to characterize the composite specimens subject to hydrodynamic ram. Based on the test results and a further comparison with a previously conducted metallic specimen test, composite T-joint concepts to hydrodynamic ram are evaluated.