Polyurethane Foam Sandwich Panel Protection Device Against Ship-Bridge Collision

With the development of transportation industries and economy, more and morebridges are building. These bridges are longer and bigger than before. As the developmentof transportation structure adjustment and the improvement of technology and navigationwaterway traffic conditions, the scale of the ships is growing larger. The ships are runningfaster and faster. As a result, the probability of ship collision is increasing. Theconsequence is more serious. As the hazmat transportation and terrorism, the research ofship collision is significant.More and more experts in the world have committed themselves to studycost-effective protective measures. It is an inevitable trend to do research on new structureswith excellent impact resistance and improving the production of protective devices. Withexcellent impact resistance, sandwich has been widely used in the aviation, traffic, military,but it has not yet used in the bridge protection devices. The major work and conclusions arelisted as following:(1) To gain an intimate knowledge of ship-bridge collision problems and summing upthe realities, hot issue and difficult points based on the reading of related materials.(2)According to the theory of collision mechanics and non-linear finite element, thecollision process of ship and protection device is simulated by the softwareANSYS/LS-DYNA. The collision force, structural damage deformation, energy exchangeare discussed in the collision process. It turned out that the collision between ship andprotection device abide by the law of conservation of energy. The kinetic energy of ship ismainly absorbed by the protection device and the ship in the form of plasticdeformation.The collision force is significantly reduced by setting up protection device,andthe damage deformation is under controlled at the same time.(3)The basic theories of non-linear finite element and the key technique ofANSYS/LS-DYNA are discussed. The excellent impact resistance of sandwich is provedby simulated calculation, compared with the ordinary steel plate in the same impactcondition. The influence of the sandwich size parameters to the ability against collision isalso studied. Results show that sandwich is lightweight high strength.Every element ofsandwich absorbs the energy uniformly and high utilization ratio of material.It can beimproved the crashworthiness performance by optimizing the structure.(4)The improve design of replaceable protection device is study by the use of sandwich. The ability against collision of the improved replaceable protection device isevaluated by the functions of limiting the collision force and absorbing striking energy.Itproves that improved protection device has good crashworthiness performance as thesandwich.And the collision force is reduced; the energy absorption ability is improved. Thedamage deformation of ship is reduced futher.The ship is protected.