Static And Dynamic Characteristics And Vehicle Bridge Coupling Vibration Analysis Of Spatial Y-shaped Steel Arch Bridge

Since the reform and opening up,the rapid development of the national economy and the ever-increasing spiritual and cultural pursuits have put forward higher requirements for bridge construction.Therefore,for many bridge projects,they are no longer simply free from society as a project example.Outside of life,but as a work of art,it is endowed with a richer humanistic atmosphere and integrated into social life.The special-shaped arch bridge is deeply loved by people due to its exaggerated form of expression and unique cultural and artistic connotation,and therefore has become a very competitive bridge type among landscape bridges.However,special-shaped arch bridges have the characteristics of diversified structural systems,diversified modeling forms,and complex stress and deformation states,which make it difficult to grasp the structural mechanical properties and changing laws of special-shaped arch bridges.In addition,large-span highway special-shaped arch bridges are related to vehicle safety during operation.And the research on driving comfort is less.Therefore,it is necessary to carry out research and analysis on the static and dynamic mechanical properties of long-span special-shaped arch bridges,as well as the sensitivity of structural parameters and vehicle-bridge coupled vibration.Based on the Jinghe Bridge in Xianyang City,the static and dynamic analysis model of the bridge was established using the finite element software Midas civil,and the vehicle-bridge coupling model of the special-shaped arch bridge was established using ABAQUS 2019,and the static characteristics of the special-shaped arch bridge were respectively established,Dynamic characteristics and the sensitivity of structural parameters,and the vehicle-bridge coupled vibration of the spatial Y-shaped arch bridge are studied.The thesis mainly carried out the following aspects of work:1.Summarizes the origin hypothesis and development process of traditional arch bridges,as well as the scope of application of special-shaped arch bridges in current bridge construction and the advantages over other bridge types;summarizes the research history of vehicle-bridge coupling vibration and the research of bridge vehicle-bridge coupling vibration Development direction;introduced the research content of this article.2.The Jinghe Bridge in Xianyang City as the research object is introduced,and the various components,structural characteristics and boundary loads of the special-shaped arch bridge are analyzed in detail;the finite element software Midas civil 2019 is used according to the structural characteristics and actual data of the research object A finite element model of the full bridge is established to provide a basis for the analysis of the stress characteristics of the special-shaped arch bridge.3.Considering the dead load(structure weight + second stage dead load),live load,temperature,wind and other loads and combined working conditions,first,perform a static analysis of the special-shaped arch bridge in the completed state,and obtain the The mechanical characteristics of the main arch rib of the special-shaped arch bridge under the four working conditions and the cable force distribution state under the use state of the suspender;finally,the three structural parameters under the dead load and live load are analyzed(ratio of rise to span,split of double arch section).The influence of fork angle and suspender arrangement form)on the static characteristics of the space Y-shaped arch bridge.4.Firstly,the theory of bridge dynamic analysis is introduced;then the natural vibration characteristics of the spatial Y-shaped arch bridge are dynamically analyzed,and the first ten modes and natural frequencies of the special-shaped arch bridge are extracted,and then the self-vibration characteristics of the special-shaped arch bridge are analyzed.Vibration characteristics;finally,using the frequencies of the four modes of the special-shaped arch bridge as the standard,three structural parameters(ratio of rise to span,bifurcation angle of double arch section and suspender arrangement)are analyzed for the natural vibration of the Y-shaped arch bridge in this space.The influence of characteristics and stability.5.First,the vehicle-bridge coupling problem is described,and the current commonly used modeling methods of vehicles,bridges and uneven roads are introduced;then the finite element software ABAQUS 2019 is used to establish the whole bridge model of the Jinghe Bridge,and the model is established with Midas civil The whole bridge model established in the document was used as a benchmark for reliability verification;then,ABAQUS was used to establish a seven-degree-of-freedom vehicle model,and a solid uneven pavement model was established by writing the ABAQUS kernel command to obtain the bridge surface unevenness value;The special-shaped arch bridge model,the whole vehicle model and the road smoothness model are the research objects.The influence of vehicle speed and road smoothness on the space Y-shaped arch bridge is calculated and analyzed.