Analysis Of Static And Dynamic Performance Of A Single-tower Suspension Bridge With Special Shape

With the increasing number of vehicles in the city,the traffic in the city is extremely busy.In order to reduce the pressure of urban traffic,pedestrian overpasses have been added.In recent years,with the improvement of people’s requirements on urban landscape,urban pedestrian bridge,as a part of urban landscape,must be considered in the design process of its complementary and coordination with the environment.Because suspension bridge has the advantages of long span,good economic performance and graceful shape,it is often used in the design of pedestrian bridge.The single-tower special-shaped suspension bridge is a new type of bridge,which not only has the advantages of suspension bridge,but also has the characteristics of saving land resources,graceful shape,and coordinating with the surrounding environment and structure.At present,there are few studies on the special-shaped suspension bridge with single tower.In order to ensure the smooth construction and normal operation of a special-shaped suspension bridge with single tower,it is particularly important to analyze its mechanical properties.In this paper,the static and dynamic characteristics of pedestrian bridge are systematically studied by means of numerical simulation and taking a special-shaped suspension bridge with a single tower as the engineering background.First of all,the history of pedestrian suspension bridge,the overview of pedestrian suspension bridge and the status of research,put forward the research significance and content of this paper.The related theories of mechanical analysis of suspension Bridges are summarized.The development of static theory mainly goes through three stages: elasticity theory,deflection theory and finite displacement theory.The calculation theory of dynamic characteristics is approximate method or empirical formula,classical analytic method and numerical method.The geometric nonlinear analysis of suspension Bridges mainly includes incremental method,iterative method and hybrid method.Through the analysis of different theories,this paper introduces the applicable conditions,advantages and disadvantages of each theory.Second,the static part.In this paper,the engineering situation of a single tower special-shaped suspension bridge is introduced.Based on the analysis of the equilibrium state of the finite element model,the internal force and deformation of the structure under temperature load and static wind load are analyzed.The force law of suspension bridge under constant load density,stiffness of each member of the structure and temperature are studied.Finally,the dynamic part is mainly the study of human-induced vibration.This paper summarizes the current norms on pedestrian load model and comfort level of pedestrian bridge,and through comparing their advantages and disadvantages,determines the pedestrian load model and comfort level limits in this paper according to the actual situation of background bridge.By using the finite element model,the frequency of 10 orders is extracted,the sensitive frequency is analyzed,and the comfort level of the frequency in the sensitive range is evaluated.The vibration is reduced if the comfort level does not meet the requirements.Based on the comparison of several vibration reduction measures at present,TMD vibration reduction measures are selected for the consideration of the aesthetics of the bridge and the effect of vibration reduction.The reasonable TMD parameters are calculated and the ideal vibration reduction effect is achieved.