Response study of concrete gravity dam against aircraft crash

Concrete gravity dam is considered as acritically important mega structure and lifeline of countries with rich water resources. Its failure due to natural and manmade hazard may cause a huge loss of human life and economy. The recent terror attacks involving intentionally crash of aircrafts have raised the safety concern of these critical structures. In the present study, a finite element analysis has been carried out to analyse the behaviour of concrete gravity dams against possible aircraft crash. Reaction-time curve of fighter jet Phantom F4 has been applied on the crest of the dam from upstream face. The Concrete Damaged Plasticity model has been incorporated to predict the behaviour of concrete under high strain loading. It has been found that at a crash speed of Mach 1, fighter jet had caused severe damage to dam. Although the penetration will be small on the loading face of the dam due to massiveness of structure, however, the concrete around crest and neck will fail in tension. Further, redistribution of moments will cause failure of the structure. Maximum deformation has been found to be 8.8 mm. Stresses are quite high at the impact face, however it diminishes at a depth of 8 m from the impact face. (paper)