Behavior of Steel Structures under Repeated Impact Loading

Abstract

In this paper the authors present a new method of analysis on the behavior of steel structures under repeated loading. This kind of problems have been dealt mainly on the basis that impact load can be replaced by a suitable static load. According to this basis, there are some difficulties to explain actual behaviors of structures such as the deformation of a structure under repeated impact loading of constant magnitude is developed and finally reaches a certain definite amount when the magnitude of impact is less than the critical. On contrast with this, the method is based on the concept that the work done by impact load must be equal to the strain energy stored in the structure due to its deformation. This analysis showed that the possible elastic energy to be stored in the structure increases as the plastic deformation becomes larger and consequently when the possible elastic energy becomes equal to the energy of impact loads in magnitude, the deformation does not further proceed. However, if the impact energy is greater than the critical impact energy, the structure will continue to deform under repeated impact loads. The result of analysis was compared qualitatively with the experiment taking into account of the efficiency of impact energy for the deformation.