| dc.description.abstract | Along the past years, Taiwan could become a developed country. The convenience of the pavements network has become an important foundation for the modern economy and society development. It is also used to evaluate the economic and social modernization. The urban road system is the most important infrastructure. Hence, the quality requirements have grown. Therefore, in 2007, the Construction and Planning Agency Ministry of the Interior promoted the ＂Urban Road Maintenance Management and Pedestrian Environmental Accessibility Assessment Project＂ for more than 10 years. In 2015, the International Roughness Index (IRI) surveys were carried on since it was included in the evaluating objectives. The main purpose of this study is to explore the IRI current situation in each city and analyze whether those evaluations are able to bring improvements to the pavement. Central government and Counties have used IRI to evaluate the road roughness. The scope of this study covers six special municipalities in Taiwan from 2015 to 2018. The special municipalities are Taipei City, New Taipei City, Taoyuan City, Taichung City, Tainan City and Kaohsiung City. A total of 586 urban roads and 948 lane kilometers resulted in the collection of 18,960 IRI data. Statistical analysis are used to understand the distribution of overall data and to enhance a detailed comparison of the IRI in different cities over the years. The results show that the mean value of the six special municipalities, from 2015 to 2018, is 3.99, 3.25, 3.09 and 2.95 respectively. The overall performance is good and improving every year. Most of the critical values appeared at the intersections (include manhole) which cause significant impact to passenger’s comfort. 15.3% of the roads in the research are within an excellent IRI range, which is of 0 to 3.5. Hence, it is recommended to divert attention to roads with higher IRI values. | en_US |