In this paper, five empirical formulae developed for bridge design are introduced, and each term of each formula is discussed in detail. A 5,000DWT bulk carrier is modeled by commercial finite element software Ls-Dyna. Then, calculated results of the five formulae are compared with numerical results for several ship-rigid wall impact scenarios, in which Pedersen formula and TB formula (the formula in "Fundamental code for the design of railway bridge and culvert") are selected to be further discussed because both of them include factors relevant to the deformation of the impact ship during the collision. Finally, the elastic deformation coefficients in TB formula used before are found to be too large, and the kinetic energy reduction factor is not a constant value as specified, but a function relevant with the initial kinetic energy. What's more, the values of energy absorbed by deformation in Pedersen formula are being discussed and modified.
As the accelerated development of the maritime trade and an increasing number of river and sea crossing bridges, ship-bridge impact accidents have been constantly happening everywhere in the world, of which the consequences can be disastrous, e.g. personal casualty, environmental pollution and the loss of property. For decades, there are countless ship-bridge impact accidents. In 1980, the Sunshine Skyway Bridge across Tampa Bay in Florida, the United States collapsed after being hit by M/V Summit/Venture Bulk Carrier, resulting in 35 death and great financial loss: the ship valued 1.3 million dollars while the bridge valued 2.5 million dollars. In 2002, a Russian cargo ship fully loaded with fuel ran into a bridge when navigating across Neva River for some mechanical problems, leading to oil spills harmfully to the environment. In China, the first recorded ship-bridge impact accident occurred in Wuhan Yangtze River Bridge in 1959, since when there has been almost 300 collision accidents along the main line of Yangtze River. In these incidents, some just caused a little damage to the bridge pier, while some led to bridge collapse, ship capsizing and serious personal casualty.
