Study of damage progression due to impact of solid bodies on laminated composite plates in water

Glass-fiber-reinforced floating vessels such as kayaks, fishing boats, lunch boats, and sporting boats are abundantly used. These vessels may collide with solid bodies at the shoreline or inside the water, causing delamination. The current investigation aims to study the impact of solid objects causing damage to the laminated composite plates (LCPs) inside the water. For this purpose, an experimental setup is fabricated to cause damage by throwing stone pallets of different masses onto the LCPs at different velocities from different standoff distances (SOD). The size of the affected damage area and the corresponding impacting force are measured through low-speed high-resolution cameras and force sensors mounted in the setup. It is observed that, the affected damage area depends on SOD, the mass of the object thrown, discharge water velocity, and the LCP material. At 650 mm SOD, the affected damage area and the impact force is maximum. Above 43.1 m/s discharge velocity, the damage caused are uniform. About 5% rise in object mass causes a 9.8% rise in affected damage area. The mechanical strength of LCPs is another factor in deciding the extent of affected damage area, thus LCPs made from woven fabrics count least affected damage area. Further, the explicit dynamic study shows that von-misses stress and deflection produced in LCPs depends on stone size and discharge pressure. About 1gm of additional mass of stone striking to LCP at 100PSI pressure (37 m/s velocity) produces 0.61–0.65 MPa rise of stress levels.