PURPOSES : In this study, the basis for improving the maintenance method of road pavement in Jeju Island, where deterioration is accelerating, was presented through field construction and analysis of various combinations of maintenance methods. METHODS : Construction was performed on Jeju Island's Aejo Road, which has high traffic and frequent early damage, using various asphalt mixtures mainly applied in Jeju Island, with different maintenance cross-sections depending on the level of repair. The quality and performance of the asphalt mixture collected during construction were evaluated, and MEPDG was used to analyze the service life according to the type and maintenance level of the mixture. RESULTS : While the mixture for the surface layer satisfied the quality standards and had excellent rutting and moisture resistance performance, the asphalt mixture for the intermediate and base layer did not satisfy the quality standards such as air voids, so it was judged that quality control was necessary during production. The section repaired to the base layer was found to be advantageous for the integrated behavior of the pavement and had the best structural integrity. As a result of predicting the service life, the estimated life of the section where only the surface layer was repaired was analyzed to be approximately 7 years, the section where the intermediate layer was repaired was 14.5 years, and the section where the entire section up to the base layer was repaired was analyzed to be 18 years. CONCLUSIONS : In Jeju Island, where deterioration is accelerating, it was analyzed that when establishing a maintenance plan, it is necessary to consider repairing the middle and base floors in order to secure the designed life of 10 years.

PURPOSES : The purpose of this study is to provide basic data to improve the service life of asphalt pavement using basalt aggregate in Jeju Island by evaluating the performance of asphalt pavement through analysis of material and structural aspects. METHODS : To evaluate the performance of Jeju Island's asphalt pavement, cracks, permanent deformation, and longitudinal roughness were analyzed for the Aejo-ro road, which has high traffic and frequent premature damage. Cores were collected from Aejo-ro sections in good condition and damaged condition, and the physical properties of each layer were compared and analyzed. In addition, plate cores were collected from two sections with severe damage and the cause of pavement damage was analyzed in detail. RESULTS : About 45% of the collected cores suffered damage such as layer separation and damage to the lower layer. The asphalt content of surface layer in the damaged section was found to be 1.1% lower on average than that in the good condition section, and the mix gradations generally satisfied the standards. The density difference between the cores of each layer was found to be quite large, and the air voids was found to be at a high level. CONCLUSIONS : Test results on the cores showed that, considering the high absorption ratio of basalt aggregate, the asphalt content was generally low, and the high air voids of the pavement was believed to have had a significant impact on damage. High air voids in asphalt pavement can be caused by poor mixture itself, poor construction management, or a combination of the two factors. Additionally, the separation of each layer is believed to be the cause of premature failure of asphalt pavement.

PURPOSES : The purpose of this study is to evaluate an asphalt mixture via field application to utilize basalt aggregates produced on Jeju Island for a warm mix asphalt (WMA). METHODS : Using commercially available WMA additives, an indoor experiment is conducted on low- and high-void aggregates among basalt aggregates on Jeju Island. The physical properties of the WMA mixture are evaluated using one solid type and two liquid types of WMA additive. To evaluate the applicability of the WMA additives, air void, saturation, aggregate void, Marshall stability, flow number, indirect tensile strength, and toughness tests are performed. For the field application of WMA using basalt aggregates, three types of pavements (HMA, WMA-Solid, and WMA-liquid) are constructed. When applying the pavements in the field, an anti-stripping agent is incorporated to improve the water resistance while considering the characteristics of the basalt aggregate. Samples are acquired via plant and field coring to evaluate the properties of the materials applied in the field. RESULTS : In the indoor test for analyzing the applicability of the commercialized WMA additives to basalt aggregates, all tests except the indirect tensile strength test show results that satisfy the standards. All test results, including that from the indirect tensile strength test, satisfy the standard values in the test that uses the sample material obtained from the plant. Similarly, in the test with field cores, all test results satisfy the standard values. Therefore, the experimental value in the field application is generally higher than the test value in the indoor experiment. It is inferred that this is due to the difference between the basalt aggregates used in the indoor and field experiments, as well as the addition of the anti-stripping agent. CONCLUSIONS : Basalt aggregates produced on Jeju Island can be used for WMA pavements, as demonstrated via indoor experiments and field applications. However, owing to the characteristics of basalt aggregates, a method for improving water resistance should be considered, and tests to determine the indirect tensile strength should be performed using various basalt aggregates. In addition, because various basalt aggregates exist owing to the diverse geology characteristics of Jeju Island, they should be evaluated via more experiments and field applications.