Based On The Actual Measured Data Establishing Pavement Smoothness Mathematical Mode

The asphalt pavement is widely applied to the highway construction because of its surface smooth, driving comfort, and many other advantages. However, with the growth of traffic, driving highly channelizing of vehicles and the aggravation of overloading, there are many damage forms produced in asphalt pavement, such as rut, passage, hug and so on. This situation not only affects traffic speed and threatens driving safety,but also greatly reduces the high-grade road using performance. The worse of road using performance mainly displays in the pavement smoothness getting worse. As one of the most important indexes evaluating road using performance, pavement smoothness, good or bad, is involved in many aspects. So, it is the key to research pavement smoothness problems that transforming the related problems of pavement smoothness into math problems, summarizing and analyzing the stochastic situation of pavement smoothness to find its rule and establish its relevant mathematical model in the process of research. This paper is mainly exploring a feasible mathematical method to research pavement smoothness and establishing a comparatively accurate mathematical mode, in orderto lay the foundation of the following research about Vehicle-Road coupling model and road using performance.At the front parts of this paper, the author summarizes the related knowledge of smoothness, and then shows the relationship among pavement smoothness indexes through the IRI, so that every index can be transformed into each other by mathematical way. Afterwards, this paper characterizes the pavement wave by sine function, drawing the expression between pavement smoothness standard deviation and pavement waveform parameters. And then,for the three indexes that two pavement waveform parameter adds pavement smoothness index,assuming one of them as known,get the relationship between another two parameters by some math method such as Lagrange interpolation or regression analysis etc. and thus establish road smoothness mathematical model. Becides, because our subject-researching-group have get the actual pavement smoothness index data from highways around Chongqing city, it can be optimized by the math method introducing in this paper for processing data, and then we can get the data of pavement waveform parameter by the relationship abtained in the front parts. Before the process of dealing with the actual pavement smoothness index data, a concept called middle-error is raised to pretreat the data to optimize data. Next, in the process, the pavement wave is divided into many sections with the concept of confidence error given in the paper, and it is proved that the methed given in the paper is better than the traditional method. In the following,with the former methed calculating the mean value of each section and getting accurate wavelength value and amplitude value. So it can be done that obtaining the final sine function expression of pavement wave from test section, and drawing the sine function curve by application of Matlab, so that it can lay the theoretical basis and practical basis for calculating pavement wave function and the later theory research.