Study On Noise Effect Characteristics Of "Cheng-yu" High-speed Railway At Transition Of Railway And Bridge

The intercity railway is a high-speed railway connecting cities,Because of the feature of the intercity railway itself,the station should be as close to the central residential area as possible,So the line often need to build a large number of railway bridges in the city,To address the impact of residential and road rivers and other sensitive areas.When the intercity railway runs through the city,the train noise has a great effect on both sides of the environment,directly or indirectly affect the physical and mental health of residents along the line.it has aroused strong public reaction and has become an important environmental problem in real life.In order to better solve the inter-city railway train runtime environment noise issue,an important basic work is to study the noise characteristics and attenuation law of intercity railway bridge section.Therefore,this paper has carried out the following research work in many angles:(1)The Cadna/A software based on the German Scha1103 specification predicts the effect of noise barrier noise reduction on the railway bridge at the distance of 30 m,45 m and 60 m from the orbital centerline,And the relationship between the predicted value and the measured value is analyzed according to the linear regression equation,the results show that the German forecast model for China's current high-speed railway noise forecast.(2)Based on the actual measurement of the bridge section of the Chengdu-Chongqing Passenger Dedicated Line,the noise characteristics of the bridge section and its variation are analyzed.The noise attenuation at the bridge increases with the propagation distance,and the noise value increases gradually when the noise value reaches the maximum value,and the attenuation is larger.(3)Through the contrast measurement of the silent barrier at the bridge,the noise reduction effect of the sound barrier is studied.Bridge segment sound barrier has a better noise reduction effect,the noise at 30m at the maximum noise reduction.(4)In the comparison of the noise intensity between the bridge,road and bridge transition section of the noise strength contrast,the radiation level and the equivalent sound level of the train through the bridge section are the smallest,and the radiation sound level and the equivalent sound level are the largest through the road and bridge transition section.(5)Comparison of ordinary railway and passenger dedicated line noise,the overall results are not much difference,but the speed of ordinary railway is much smaller than the speed of passenger line.In this paper,the noise characteristics of the bridge between Chengdu-Yu passenger dedicated railway are studied,and the noise control measures for the bridge section are put forward,which provides a reference value for the future high-speed railway planning,noise emission limit setting and noise control.