Tire-road Noise Evaluation Method And Noise Prediction Model For SMA Rubber Asphalt Pavement

Automobile noise is a non-negligible part of traffic noise.When the speed of a car exceeds 40km/h,the noise generated by the interaction between the tire and the road becomes a major contribution to the noise of the car.Aiming at the current situation that tire-road noise seriously affects people's lives,a large number of scholars have begun to absorb low-noise tires by changing the tread pattern and other parameters from the perspective of tires and pavements.Or reduce the purpose of noise.However,there are still problems such as the tire-to-road noise detection method is not detailed,the noise variation law and the noise reduction mechanism are not clear,and the tire-road noise prediction model is not perfect.To this end,this paper carried out the design of indoor noise test method and the research and development of outdoor noise detection vehicle,and explored the influence of material parameters,tires and environment of SMA rubber asphalt mixture on tire-road noise and analyzed the mechanism.Based on this,the BP neural network noise prediction model of SMA rubber asphalt pavement is constructed.The specific research contents and results are as follows:Firstly,for the main research object of this paper—SMA rubber asphalt pavement,the necessity of indoor noise test and the feasibility of developing outdoor noise detection vehicle are briefly described.Based on the basic principles of vibration and noise,the indoor noise test method is determined as the tire free fall method.According to the similarity between the tire grounding map and the grounding pressure,and the consistency of the indoor and outdoor noise test rules,the indoor noise test method is verified.Sex.Independently developed an outdoor noise detection vehicle,introduced the sound insulation and sound absorption system,loading system and lifting system of the equipment,clarified the position of the microphone,calibrated the key parts of the equipment,and verified the accuracy of the equipment by testing background noise and reflected noise..Then,using the indoor tire free fall method,the index of the noise reduction performance of the SMA rubber mixture was proposed.The influence of the material parameters of the SMA rubber asphalt mixture on the tire-road noise was analyzed.The mechanism of the noise change was clarified.SMA rubber asphalt pavement mix design method for noise reduction.The research shows that the amount of rubber powder and the amount of asphalt have a significant influence on the vibration noise.The nominal maximum particle size and the critical mesh passage rate have a significant influence on the pumping noise,and the road surface thickness has little effect on the noise.At the same time,the outdoor noise detection vehicle was used to study the influence of ambient temperature and tire on the tire-road noise and the mechanism analysis was carried out in combination with the spectrogram.The temperature correction formula of noise was given,and the vehicle speed,road surface temperature and tire were established.Road noise connection.The results show that the sound pressure level of tire-road noise decreases linearly with increasing temperature,increases with the increase of speed,and increases with the increase of tire load.Finally,according to the main factors affecting the tire-road noise measured indoors and outdoors,BP neural network algorithm is adopted,with the pavement structure depth TD,vibration attenuation coefficient,tire load P,driving speed V,and road surface temperature as the input layer parameters.The A-weighted sound pressure level LA is the output layer parameter.Based on the principle of error and computational efficiency balance,other basic parameters of the neural network are determined.The tire-path noise prediction model of SMA rubber asphalt pavement is constructed and verified.