Analysis Of Dynamic Effect Of Cable-stayed Pipe Bridge Of Carbon Fiber Cable

The long-span cable structure spanning system plays an indispensable role in the pipeline transportation project of oil and natural gas.Because the cable structure is exposed to the air for a long time,it is affected by the natural environment,temperature and humidity changes,and the cable is prone to rust.A cable accident occurred.The excellent physical and chemical properties of high-strength,high-strength,corrosion-resistant,and high-temperature resistant carbon fiber cables will effectively solve the problems faced by traditional steel cables.However,carbon fiber materials are rarely used in practical bridge projects.The relevant research results are weak and they are lightweight.Carbon fiber cable instead of the traditional steel cable will make the structure of the full bridge more gentler,and its changes in wind and seismic performance are particularly known.In order to solve the above problems,this paper takes a bridge as the engineering background,and comprehensively analyzes the dynamic characteristics of two types of long-span cable-stayed-suspension pipe bridges using steel and carbon fiber materials as cable structures.The main research contents are discussed.Conclusion as below:(1)Relying on the Weijing line Hanjiang spanning bridge and cable replacement project,analyzing the difference between the cable-stayed bridge and the ordinary highway bridge,summed up its own characteristics.Through the principle of axial equal strength,the traditional steel pipe of the pipe bridge and the traditional cable of the stay cable are replaced with carbon fiber materials,and the two types of replacement schemes of steel cable replacement and carbon fiber cable are provided.(2)Select the Davenport horizontal pulsating wind spectral density function,based on the autoregressive model in the linear phase filter method,simulate the three-dimensional pulsating wind field at the bridge span of the Hanjiang River through Matlab,and extract the turbulent parameters of the pulsating wind field as the cable wind.The boundary condition of vibration was studied.Through the Workbench work platform,the one-way fluid-solid coupling between the wind field and the cable was realized.The similarities and differences between the wind-induced vibration responses of the carbon fiber cable and the cable were calculated,and the changes in the aerodynamic characteristics of the bridge were analyzed.The results show that the use of carbon fiber cable as the cable material will increase the cable deformation and increase the cable stress.The wind-induced carbon fiber wind-induced vibration response displacement is larger than that of the traditional steel cable,but it decays faster with time.(3)Combining the mechanical characteristics of cable-stayed-suspension pipe bridges,the coupled-parameter vibration model of the bridge-tower cable-girder bridges is established.The Matlab tool is used for numerical calculation;Carbon fiber cable and steel cable are compared from the aspects of dynamic characteristics and amplitude.Parameter vibration performance,analysis of various impact parameters such as: bridge surface displacement,cable force,tower tower stiffness,cable damping and other parameters of the impact of vibration;Add viscous damper,damping damper model established,comparative analysis of two kinds of material pull Cable vibration control effect.The results show that the main resonance amplitude becomes larger and the subharmonic resonance decreases after the cable is replaced with carbon fiber cable.As a whole,the amplitude of the cable is changed and the parameter vibration performance is unfavorable.After the viscous damper is added for passive control,the carbon fiber cable is reduced.The vibration effect is better than the steel cable and the amplitude is significantly reduced.(4)Based on the response spectrum and seismic time history analysis theory,use Midas Civil to analyze the dynamic characteristics of cable-stayed-suspension pipe bridges,select the appropriate response spectrum and seismic wave according to the specifications,and select the appropriate working conditions to discuss the response spectrum effects of the structure.The dynamic response of the structure is considered;the dynamic response of the structure under the excitation of one-dimensional,multi-dimensional,uniform and multi-point seismic waves is considered,and the influence of different seismic waves on the structure is determined;and the deformation and internal force of the carbon fiber cable structure and the cable structure are compared and analyzed.Discuss the impact of the cable on the structure.The results show that the cable-stayed-suspended tube bridge has a smaller frequency and longer period.The response spectrum is the most obvious,whether it is the response spectrum or the seismic wave.It depends on the transverse stiffness of the structure and the structure excited by the 3D seismic wave.The most dangerous;after the cable is changed,although the flexibility of the structure is increased,the seismic response to the structure is favorable.