Study And Analysis Of Structural Noise Of Continuous Slab Beam Steel-concrete Composite Beam Bridge Based On FE-SEA Hybrid Method

Railway transportation has become one of the most important means of transportation due to its advantages such as large transportation capacity,fast transportation speed,low transportation cost,small land area,low energy consumption,good versatility,safety and reliability,high on-time rate and little impact from the natural environment.Since China opened its first high-speed rail line in 2003,high-speed rail construction has been booming across the country.With the rapid development of high-speed railway and intercity transportation in China,while driving the rapid development of China's economy and bringing convenience to people's travel,the noise problem is constantly affecting people's life,and with the continuous improvement of people's living standard,people pay more and more attention to this problem.On the other hand,compared with the subgrade section,the noise of the bridge section is more prominent,and the bridge takes a high proportion in the rail transit lines in China.Therefore,it is of great significance to study the vibration response and noise propagation law of the bridge structure as well as the vibration and noise reduction measures.Continuous plate girder steel-concrete composite girder bridge is more and more frequently used in rail transit because its span is larger than that of other Bridges.However,the noise generated by continuous plate girder steel-concrete composite girder bridge is harmful to human body,causing a large number of complaints from residents along the line,which is also an important factor restricting its development.In this paper,the research work is carried out on the generation and propagation rules of structural noise and the measures of vibration reduction and noise reduction of continuous plate beam steel-composite beam bridge.In this paper,based on the acoustic-solid coupling theory,combined with the advantages of finite element method(FEM)and statistical energy method(SEA),the fe-sea hybrid method was used to establish the structural noise prediction model of continuous plate girder steel-composite bridge.The model is divided into FE and SEA sub-system,which can not only avoid the problem of low efficiency in the calculation of high frequency by finite element method(FEM),but also make up the problem of imprecision in the calculation of low frequency by statistical energy method(SEA),and well solve the contradiction between the calculation efficiency and the calculation accuracy.The main work of this paper is as follows:(1)This paper introduces the development of rail transit in our country present situation and the research status of bridge vibration and noise,this paper expounds the continuous board joist steel-mixed combination bridge for vibration and noise,and the necessity of research on the vibration noise reduction measures,and points out the present research on continuous board joist steel-mixed combination bridge noise,also introduces the basic theory of FE-SEA hybrid method and bridge structural sound radiation theory,and then introduces the main research contents in this paper.(2)Firstly,based on the vehicle-orbit-bridge coupling dynamics theory,the vehicle-rail-bridge coupling model is established by SIMPACK software.The orbital height and low irregularity are used as the excitation to obtain the vertical fastener force in the time domain,and then undergo FFT transformation.Find the vertical 1/3 octave fastener force in the frequency domain.(3)Using VA one software to establish a continuous beam-beam steel-hybrid composite beam bridge model.According to whether the number of bending modes of the plates of the continuous plate beam steel-mixed composite beam bridge in different frequency bands is greater than 5,the bridge model is established in the sub-band,and the structural noise of the steel-mixed composite beam bridge is mainly medium and high frequency.Therefore,the FE-SEA hybrid model is established from 20 Hz to 200 Hz,and the SEA model is established from 200 Hz to 1600 Hz,and the vertical 1/3 octave fastener force in the frequency is loaded onto the bridge deck.(4)Through simulation analysis,when the train speed is 200km/h,the vibration response of continuous plate girder steel-composite beam bridge in the frequency domain of 20 Hz ~ 1600 Hz is analyzed.Then,according to the acoustic radiation theory,the sound pressure level and propagation law of bridge structure noise are analyzed,and the acoustic contribution of each plate of the bridge is analyzed.(5)Through the simulation analysis when the train speed 200km/h respectively,250 km/h and 300km/h three kinds of working condition of continuous board joist steel-mixed combination bridge in 20Hz~1600Hz frequency range vibrating speed,vibrating acceleration,sound pressure level and sound pressure contribution amount,vibration energy level and the change of power loss and so on,the speed of different train joist steel-mix of continuous board combined with the influence law of bridge vibration and structural noise.(6)Through the simulation analysis when the bridge train respectively by one-way road,two-way,continuous board joist steel-mixed combination bridge in 20Hz~1600Hz frequency range vibrating speed,vibrating acceleration,sound pressure level and sound pressure contribution amount,vibration energy level and the change of power loss and so on,it is concluded that the bridge train at single,two-way joist steel-mix of continuous board combined with the influence law of bridge vibration and structural noise.(7)according to the local vibration and structural noise radiation characteristics of the steel-concrete composite beam bridge,the vibration response and structural noise changes of the bridge are analyzed when the material parameters and section size change,so as to summarize the influence law of each parameter on the structural noise of the steel-concrete composite beam bridge.Finally,the optimal selection range of each parameter is proposed on the premise of ensuring the safety and reliability of the bridge structure,providing a reliable basis for the vibration and noise reduction of the steel-concrete composite beam bridge.