一种基于近距法(CPX)改进的低噪声路面降噪效果预估方法

针对低噪声路面降噪效果，基于近距法（CPX）获得轮胎/路面噪声，结合交通流特性、路面声学性能和使用状态，运用声能叠加原理和户外声空间传播机理，提出一种基于CPX改进的低噪声路面降噪效果评估模型，并以多种路面组合结构试验段为例，验证该改进评估方法的准确性.改进后的路面降噪效果评估方法，可以更为准确地预测低噪声路面对于路侧边界交通噪声和道路边界外35m环境噪声的降噪贡献量.在道路车道处于不同路面结构或者使用状态下，该评估方法可以为预测评估路面的噪声水平提供方法和依据.结果表明，改进后的评估方法对于道路边界交通噪声的预测误差分别从0.8，1.5和1.1dB下降到0.2，0.1和0.2dB；而对于道路边界外35m处的环境噪声，预测误差分别从1.1，1.8和1.1dB下降到0.1，0.2和0.2dB，有效提高了低噪声路面降噪效果预测评估的准确性.

An improved noise reduction performance prediction method for low noise pavement based on CPX

An improved method was proposed to quantitatively predict the noise reduction performance for low noise pavement, which was based on the CPX (close-proximity method). According to the traffic flow characteristics, the acoustic performance of the pavement and the states of use, the method adopted the principle of sound energy superposition and spatial propagation mechanism of outdoor sound. The prediction accuracy of the proposed method was improved and further demonstrated by testing multiple composite pavement structures. This model can more accurately predict the amount of noise reduction for low noise pavement, especially when the noise level was measured at the border or at a distance of 35m from the road border. An effective way was also provided for predicting and evaluating the noise level of road surfaces when different road lanes have different pavement structures or maintenance states. Results showed that the improved prediction method could reduce the prediction error from 0.8, 1.5 and 1.1dB to 0.2, 0.1 and 0.2dB, respectively for the traffic noise at the border; and it could also reduce the prediction error from 1.1, 1.8 and 1.1 dB to 0.1, 0.2 and 0.2dB, respectively for the noise that is 35m away from the border.