Download or read book Development of a Direct Type Road Roughness Evaluation System written by Fengxuan Hu and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: From field experiments and data analysis, it shows: 1. Direct type I profiler showed satisfactory repeatability performances; 2. Direct type I profiler has good RN correlations High-Speed laser profiler; 3. Direct type I profiler has good correlations with Dipstick, High-Speed laser profiler in terms of IRI 4. Direct type II profiler does not has good correlation with direct type I profiler; the performance needs to be improved. Except for these conclusions, it is also found that the High-Speed profiler can be operated at different speeds with little differences in RN values, the sampling rate did show impact on RN value.