High-speed railway sound barrier insertion loss prediction method of five-sound-source mode

Abstract

The invention discloses a high-speed railway sound barrier insertion loss prediction method of a five-sound-source mode. The method comprises the following steps of equivalently simplifying a high-speed railway noise source into a wheel-rail area noise source, a train body lower part noise source, a train body upper part noise source, a current collection system noise source and a bridge structure noise source according to the composition, position, frequency characteristics and attenuation law of the high speed railway noise source, and respectively calculating the insertion loss of a wing plate for the five sound sources by virtue of a single-sound-source mode; spreading the noise of a wheel-rail area, a train body lower part, a train body upper part, a current collection system and a bridge structure to be superimposed with noise on a sensitive point after a sound barrier is installed, obtaining a main noise grade after the sound barrier is installed, subtracting the main noise grade from the noise grade before the sound barrier is installed, introducing an insertion loss correction item of the bridge wing plate, and obtaining an insertion loss prediction value by adopting the five-sound-source calculation method. By adopting the method, the weaknesses in the traditional sound barrier insertion loss prediction method can be overcome. The high-speed railway sound barrier insertion loss prediction method is applied to the high-speed railway sound barrier engineering design and the ambient noise influence valuation and has the advantages of accurate prediction value and high engineering practicability.

Description

technical field [0001] The invention belongs to the research field of high-speed railway noise control in the subject of environmental engineering, and relates to a method for predicting noise reduction effects of high-speed railway sound barriers, in particular to a method for predicting insertion loss of high-speed railway sound barriers with five sound source modes, which is suitable for high-speed railways Sound barrier engineering design and environmental noise impact assessment. Background technique [0002] The prediction of insertion loss of sound barrier is an important content in the engineering design of high-speed railway sound barrier. In order to predict the theoretical noise reduction of different heights of noise barriers on noise sensitive points, and to determine the reasonable height of high-speed railway noise barriers, the method proposed in the latest research results at home and abroad divides the high-speed railway sound source into upper and lower pa...

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Problems solved by technology

[0003] However, the above methods still have obvious shortcomings when predicting the insertion loss of high-speed railway sound barriers

On the one hand, the actual noise sources of high-speed railways are distributed in a large range from 3m below the rail surface to 5.6m above the rail surface. It is difficult to accurately determine the distribution characteristics of the noise sources only by using the lower and upper equivalent sound sources, and the noise source of the high-speed railway The equivalent frequency and energy ratio are not constants, but are variables related to the train speed. The insertion loss predicted by the existing method is a constant that has nothing to do with the speed of the train, and there is a certain deviation from the measured value, which brings difficulties to engineering design. In some cases, the actual noise reduction effect after installing the sound barrier is lower than the predicted value, and engineering remedial measures are required to make the environmental noise reach the design target value, which passively increases the amount of engineering construction and capital investment; on the other hand, this method can only predict the upper part The insertion loss when the sound source is completely unobstructed by the sound barrier greatly limits its scope of application

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