Improving the Dynamic Properties of Pedestrian Overpasses by Including a Reinforced Concrete Slab in Structural Behavior

Abstract

AbstractAboveground pedestrian overpasses are generally vulnerable to dynamic impact, due to their high slenderness ratio. The situation is aggravated by the possibility of matching of the natural oscillation frequency and the frequency of walking of people, which can lead to the appearance of resonant phenomena. The article considers one of the possible ways to reduce the period of natural oscillations of an aboveground pedestrian overpass by including a reinforced concrete slab structure in structural behavior. There is a well-known design of the pedestrian overpass consisting of the main longitudinal and transverse beams on which the profiled flooring filled with reinforced concrete is laid. Dynamic tests of the structure were carried out in order to determine the period of natural oscillations. Two structural designs have been developed. In the first one, the reinforced concrete slab is not included in structural behavior and is set by nodal masses. In the second structural design, the reinforced concrete slab is modeled with volumetric finite elements and acts in collaboration with steel plate finite elements. Based on the results of comparing the theoretical periods of natural oscillation of the two structural designs, the influence of the reinforced concrete slab on the period of natural oscillation of the structure is determined.KeywordsPedestrian overpassesDynamicsOscillationDynamic loadingConstructionStructures