Influence Of Railway Subgrade Form On Catenary Positive Feeder Galloping In Strong Wind Area And Research On Interphase Spacer To Anti-galloping

Lanzhou–Urumqi high-speed railway electrification railway is a high-speed railway with the highest altitude,the most complex terrain,the longest traffic mileage and the most technical problems.It passes through three provinces of Gansu,Qinghai and Xinjiang and passes through five strong wind areas.The geological environment along the line is complex and the sand dust and wind disaster is serious,which is easy to lead to train overturning accidents.In order to prevent the frequent occurrence of such accidents,a windbreak wall or windshield project has been established along the wind area,but the windbreak wall or windshield set up in the "guards against train without guards against nets" has caused the galloping phenomenon of the catenary positive feeder,resulting in serious wear and tear of the catenary positive feeder clues and insulators,and the line is prone to line drop and power failure accidents,threatening the safe and stable operation of the electrified railway.Therefore,it is necessary to further clarify the galloping excitation factors of the main feeder of Lanzhou–Urumqi high-speed railway,put forward the corresponding anti-galloping measures,study and analyze its anti-galloping effectiveness.Firstly,the wind tunnel test device is built and the scale model corresponding to the wind tunnel test is established.The simulation results are compared with the wind tunnel test results to verify the correctness and effectiveness of the full-scale model numerical simulation method in this thesis.The models without and with windbreak wall are established respectively,and the influence law of the existence of windbreak wall on the aerodynamic characteristics of catenary positive feeder is analyzed.Then,the simulation model with windbreak wall is established when the ground structure is flat,and the differences and rules of aerodynamic characteristics of catenary positive feeder at different inlet wind speeds are analyzed.At the same time,change the embankment height and embankment slope rate in turn,and analyze the change trend of different embankment height and embankment slope rate on the aerodynamic characteristics of the catenary positive feeder when there is a wind retaining wall.Secondly,the numerical simulation model of the bridge structure is established to analyze the velocity cloud diagram of the catenary positive feeder when the bridge has no windshield and the bridge has windshield,as well as the variation characteristics of the catenary positive feeder aerodynamic lift coefficient and resistance coefficient.The results show that although the bridge windshield is lighter and thinner than the embankment windshield,it has the same accelerating effect on the catenary positive feeder aerodynamic characteristics as the embankment windshield.Then,the height of the windshield and the aerodynamic characteristics of the catenary positive feeder when the windshield is set with different air permeability are analyzed.The results show that the larger the ventilation rate of the windshield,the smaller the lift coefficient and resistance coefficient of the positive feeder.Considering the impact on the safe operation of the train,the ventilation effect of 40%windshield ventilation rate is the best.Finally,simplify the catenary positive feeder into a single span conductor,use the analytical method and finite element method to calculate the form finding under self weight load respectively,and analyze the first four vibration modes and natural frequencies of the catenary positive feeder,and verify the correctness of the form finding of the catenary positive feeder by the finite element method.Then,the aerodynamic load obtained from the simulation of the catenary positive feeder is loaded to simulate the galloping time history,and the transverse displacement,vertical displacement and vertical displacement spectrum of the catenary positive feeder without the phase to phase spacer anti-galloping device and after the phase to phase spacer device is installed are compared to analyze the anti-galloping effectiveness of the phase to phase spacer device.