基于离散元法的集料针片状含量对行车振动噪声的影响

为了给低噪沥青路面的设计与施工提供参考,研究了沥青路面的集料针片状颗粒含量对行车振动噪声的影响.通过理论分析、现场噪声测试和离散元模拟计算,论证了行车振动噪声与轮地接触压力的关系,提出利用轮地接触压力的波动性评价行车振动噪声的方法.采用离散元颗粒流软件PFC3D构建了4种不同针片状颗粒含量的沥青路面模型以及车轮模型,分别模拟车轮在不同车速下在这4种路面上的运动过程,并计算轮地接触压力,分析其波动性,进而评价行车振动噪声.研究结果表明,当针片状颗粒含量为0、10%和15%时,针片状颗粒含量与行车振动噪声之间没有明显的相关性;当针片状颗粒含量为20%时,其行车振动噪声要明显高于低针片状颗粒含量的路面.因此针片状颗粒含量过大,不仅会影响集料的施工和易性、降低混凝土强度等,还会导致较高的行车振动噪声.

Effect of Flat Elongated Particle Content on Driving Vibration Noise Based on Discrete Element Method

In order to provide reference for design and construction of low noise asphalt road, the effect of flat elongated particle content on driving vibration noise was studied. The relationship between driving vibration noise and tire road contact pressure was investigated by theoretical analysis, field noise tests, and simulations via the discrete element method (DEM). Besides, a new evaluating method for driving vibration noise based on tire road contact pressure was proposed. The asphalt pavement models with four flat elongated particle contents were built using particle flow code (PFC). Meanwhile, the movement of wheels on these four different pavement surfaces was simulated and the contact pressures were calculated. Finally, the volatility of contact pressure was analyzed. The results show that the effect of flat elongated particle content on driving vibration noise is insignificant at the level of 0, 10%, and 15%. However, the driving vibration noise of asphalt pavement with 20% flat elongated particles is greater than those with lower flat elongated particle content. Thus it can be concluded that excessive flat elongated particle content has a negative influence not only on workability and strength of asphalt mixture, but also on driving vibration noise.