عنوان مقاله [English]
Drainage conditions of base and sub-base layers are one of the key factors that affect serviceability of asphalt pavement of the roads. The non-destructive testing method of ground penetrating radar (GPR) has been considered as an applicable method in this respect. In this paper, the relationship between obtained data from recorded images by GPR machine and moisture content of asphalt pavement system was investigated. Eighteen cylindrical samples with 80 cm diameter and height were constructed from asphalt, base, sub-base, compacted medium and natural medium in three different moisture percentages, and then were compacted. Then, a GPR machine, with 250 MHz antenna, was conducted over samples for profiling survey and the obtained radar images were analyzed statistically using Labview software. Comparison of the statisticall parameters obtained from the images showed that distribution of kurtosis is similar to a normal distribution and has logical and interpretable variation-trend with moisture percentage. Therefore, by using a linear curve, fitted between kurtosis and moisture content, an equation was extracted which could help to estimate nearly accurate the moisture content of pavement layers, based on the output of GPR test.