Study Of Vibration Response And Control Of Combined Load For Scenic Pedestrian Suspension Bridge

Because of its strong spanning ability and beautiful shape complementing the natural scenery,the suspension bridge for pedestrian has become the preferred bridge type for most of the natural scenic spots that cross the gully and lake.In addition,in most scenic areas,only pedestrians are allowed to enter on foot,so suspension bridges are sufficient to meet the traffic requirements within the scenic area.When an emergency occurs in the scenic spot,waiting for the arrival of a large rescue vehicle may delay rescue time.At this time,if a light-weight battery ambulance used in the scenic area could through the suspension bridge to arrive at the accident site in advance to make some emergency measures,which can reduce the personal and property losses of scenic spots and tourists accordingly.Meanwhile,there is still a need to ensure that the passage of light-duty battery vehicles will not cause discomfort and panic of the pedestrians on the bridge.Therefore,It is necessary to analyze the influence of the joint effects of the light vehicle and bridge pedestrian for the pedestrian suspension bridge and the corresponding vibration control.This paper use APDL of finite element analysis software ANSYS to establish the finite element model of pedestrian suspension bridge,and use this model to make various analyses.The main research contents and research results are as follows:(1)In order to allow the light battery car to pass,the wooden bridge surface of the existing suspension bridge was changed to a non-slip steel plate firstly and rigidly connected with beam.The lateral rigidity of the overall structure of the suspension bridge was improved.(2)Use controlled single-variable method to comparison the impacts of various design parameters for the modified pedestrian suspension bridge,and summarize the effect of various design parameters on the overall natural vibration frequency of the bridge structure so as to effectively increase the structural stiffness during the design phase.(3)Briefly introduce and compare existing comfort standards and select one as the evaluation criteria.Use finite element software ANSYS to analyze the vibration response of the suspension bridge under the pedestrian load,light vehicle load and pedestrian-light vehicle load.The results show that the vibration response of the bridge structure meets the comfort standard when the pedestrian load and the light vehicle load act independently on the bridge deck slab;When the combined load acts,there will be a large vibration response,requiring some control measures to reduce vibration.(4)The control effect was analyzed by adding external control measures,controlling the number of light vehicles and controlling the load position of the pedestrians and light vehicles as control measures.The wind resistance cable can effectively control the vibration response of the bridge when the pedestrian increases the step frequency;According to the actual situation,when the light vehicle is on the bridge,try to make the pedestrian heading down the bridge to avoid the bridge pedestrians staying on both sides of the bridge to ensure the safety of light vehicles and pedestrians on the bridge within the comfort zone.The purpose of this paper is to make pedestrian suspension bridges in scenic spots provide a possibility to become a life channel in emergency situations,and to give more value to the use of pedestrian suspension bridges.