Theoretical Study On Key Technology Of Highway Sound Barrier

With the acceleration of social modernization,road traffic is becoming increasingly convenient,and the amount of automobiles is also raising.The obvious primary problem is the pollution of traffic noise,which directly or indirectly affects people’s work,study and life.Therefore,it is pressing to deal with the problem of traffic noise pollution.Sound barrier is a method to reduce the noise in the process of traffic noise transmission.On account of its merits of convenience,economy and high efficiency,it has been extensively used in real life.In this paper,proceeding from the fundamental theory of sound barrier,design a new type of noise barrier structure of ontology,and through numerical calculation the noise attenuation performance and Acoustic radiation effect,and through the Virtual.Lab Acoustic simulation platform on the top of the common structure simulation analysis,detailed analysis the merits and demerits of each of the top structure,give a reference for the study of the theory of the noise barrier.Firstly,the form of the new body structure sound barrier is proposed,and the acoustic impedance of the new body structure sound barrier is calculated by the acousto-electric method,the sound absorption coefficient of the new body structure sound barrier is obtained,and the noise attenuation formula of the new body structure sound barrier is substituted to calculate the sound insulation amount of the new body structure sound barrier.By changing the form of the sound absorption structure,the acoustic absorptivity and sound insulation of the micro-perforated plate with differ cavity depth,different aperture,different perforation rate,different thickness,different sound absorption material,different thickness of sound absorption material and different cavity thickness were compared.As for the absorbing structure,the resonance absorption structure of the micro-perforated plate makes up for the disadvantage that the sound absorption material only has good sound absorption property in the high frequency band,while the noise absorption effectiveness in the middle and low frequency band is poor.To optimize the acoustic performance of the sound barrier,we should pay attention to the characteristics of road traffic noise rather than just the average acoustic absorptivity of the sound absorption structure.Based on the theory of acoustic radiation,the characteristic response of acoustic radiation is considered in the calculation of insertion loss of acoustic barrier.The sound radiation power and its influence on insertion loss are calculated from three basic attributes,material,length-width ratio and thickness meter respectively,which provides further theoretical support for reasonable calculation of insertion loss of sound barrier and has reference significance.Through the Virtual.Lab Acoustic simulation platform,a simulation model of the highway sound barrier was established,followed by an inverted L-shaped roof structure,an arc top structure,a T-shaped top structure,and a Y-shaped top structure.The Acoustic performance optimization of the highway sound barrier overhead structure and its variants was studied.A series of constraints such as line sound source and simulated ground are used to fully simulate the real highway scene.The applicability of various top structures and the optimal noise attenuation position are obtained.The noise attenuation effect of closed Y-shaped overhead structure is the best when compared comprehensively with the lower road.