Dynamic Response Of The Long-span Plate Subjected To Pedestrian Load

Focused on a long-span floor t,this paper first analyzes the vibration response of the solid floor with four simply supported edges under pedestrian load.Based on the structural dynamic theory,theoretical calculation and numerical simulation for the problems are used.Using the finite element software to simulate the prestressed long-span floor with four edges clamped the paper analyzes the vibration response under the pedestrian load condition,and evaluate its comfort,which contributes to the contents as follows:1.The paper introduces the form of the pedestrian load,and analyses the parameter which affects the throng pedestrian load.The function of the single step expressed by fourier series are adopted,and is simplified because of the problems of the paper.The higher-order parts are ignored and the first harmonic is left.All people walk on the floor with the same frequency and phase when analyzing the condition throng pedestrian load.2.Because the thickness of the long-span floor is much less than its length and width,the theory of vibration plate is the basic theory.Existing code of floor designing treating the pedestrian load as a kind of static load,but it is entirely different from the actual conditions.What is more,the influence brought by the people is out of the analyzing.The paper brings the concept of tractive force into the analyzing for floor.A new equation is got considering the influence of the people’s damp.The paper modifies the existing formula on the vibration response under the single and throng pedestrian load,.3.An example of a long-span floor with the size of 15 m ×15m is simulated with the finite elements software ABAQUS.A first-order single pedestrian load is exerted to the centre of the floor which is the most negative condition when considering the single person;60 loads is exerted at the fixed points when considering the throng pedestrian condition.The results of the response includ inherent frequency,mode,concentration-time curve of acceleration,concentration-time curve of displacement.By comparing the result of the calculation and simulation,the paper verifies the correctness of the coupling model between the people and floor proposed by the paper.4.The paper simulates the response of the prestressed long-span floor.According to the standard of comfort,the acceleration is adopted to be the index to evaluate the comfort.The result shows that the prestressed floor meet the demands of comforts.