Reducing Noise Pollution and Ensuring the Safety of Vehicle Drivers by Modifying the Shape and Grain Size of Road Surface Materials

One of the most effective factors in creating tire/pavement sound and reducing the sound of reflection from the asphalt surface are: pavement texture, pavement life, vehicle speed, and temperature, which in the present study, pavement texture and speed have been studied. In the present study, the simultaneous performance of pavement texture in providing friction and reducing pollution has been investigated. The English pendulum test by ASTM-T3-74 standard in wet/dry conditions was used to evaluate the skid resistance of asphalt. The depth of the pavement texture, which is determined by the size of the pavement material, is directly related to the amount of noise pollution created, and the finer the material used, the higher the sound level will be. According to the results, it can be concluded that the preparation of pavements with a higher percentage of coarse grain, can increase friction by 32% and increase noise pollution by 6% due to the movement of the vehicle. Compared to weather conditions (wet/dry), the skid resistance of wet asphalt decreased by 6%, and the amount of noise in wet asphalt compared to dry asphalt increased by an average of 1 dB. Needle aggregates were more sensitive than flake aggregates in a 15% increase in skid resistance. Also, flake aggregates were unaffected by pavement/tire noise and skid resistance. Therefore, it is recommended that in the process of preparing pavements, maintaining proper pavement friction, coarse materials, and high-speed control, especially in urban areas and sensitive areas, and pavement with proper drainage, be used.