PURPOSES : The recent increase in the application of reclaimed asphalt pavement (RAP) calls for more research focusing the evaluation of pavement performance. For this matter, this study aims at evaluating pavement performance using the application rate of RAP. METHODS: To obtain mixtures with RAP aggregate application rates of 10%, 25% and 30%, the gyratory compaction method was applied regarding the mix design process for determining the optimum asphalt content (OAC). Additionally, the in-direct tension (IDT) test, deformation strength test (DST), tensile strength ratio (TSR) test and dynamic modulus (DM) test were conducted to verify the effect of RAP application rate on pavement performance. Based on the above-mentioned results, performance evaluation was done to these RAP application of design or utilization to construction site. The performance evaluation analysis was performed using the Korean Pavement Research Program (KPRP) of second level for the pavement design. RESULTS: From the DST results, the rutting resistance was improved as the application rates of RAP were increased. Additionally, all the IDT and toughness results satisfied the quality standards of the asphalt concrete pavement. However, the results did not conform with the tensile strength ratio standards with the application rates of RAP of 25% and 30%. This means that the standards, which should be considered when the addictive regeneration material is applied to the mixture when the RAP application rate is over 25%, were reflected. CONCLUSIONS : The predicted performance decreased from the second level performance analysis with the increase in the RAP application rates. All the cases satisfied the design standards (fatigue cracking, rutting depth and international roughness index (IRI)). However, the results of them closed to these standards (up to 94% (Fatigue)).

PURPOSES : The use of reclaimed aggregate has been recently increasing with the increase in the amount of waste asphalt concrete. The application of these materials can reduce the properties of the asphalt pavement when compared with the case when recycled aggregate is not used. The objective of this study is to evaluate the performance of the asphalt mixtures with various mix ratios of reclaimed aggregate. METHODS : To measure the performance, the following tests using the mixtures prepared in accordance with the Korea Standards were conducted: Hamburg wheel-tracking test, third-scale model mobile loading simulator test, and dynamic modulus test. RESULTS : The test results of the Hamburg wheel-tracking test indicate that the water resistance was similar in each mixture and the plastic deformation resistance was good in the high-ratio reclaimed aggregate mixture. In the case of the third-scale model mobile loading simulator test, the plastic deformation demonstrated a high resistance in the high-ratio reclaimed aggregate mixture. The results were similar to those of the Hamburg wheel-tracking test; however, the cracking resistance was poor with a high recycled aggregate incorporation ratio. The dynamic modulus test results demonstrated excellent resistance to plastic deformation at a relatively high ratio of reclaimed aggregate admixture. The crack resistance was weakened when a high ratio of reclaimed aggregate mixture was used. CONCLUSIONS: As the reclaimed aggregate content increased, the plastic deformation resistance increased and the crack resistance decreased.

A aggregate size distribution of soils is an important in successful crop production in reclaimed tidelands. The aggregate size distribution for this study were determined of 0.1mm, 0.25mm, 0.5mm, 1.0mm, and 2.0mm by wet sieving method. Agricultural activity, period of reclamation showed significant effects on aggregate size distribution in reclaimed tidelands. Aggregate MWD was greater in SS and KH(above 1.0m) than in YSG, GHD, SMG, and DH(below 0.5mm) reclaimed tidelands and tidelands. The percentage of aggregates less than < 2mm for SMG, GHD, and SM reclaimed tidelands and tidelands were ranged 8.9%, 36.7%, and 38.0%, respectively. The percentage of > 0.1mm aggregates for SMG, GHD, and SM reclaimed tidelands were ranged 9.0%, 26.0%, and 48.9%, respectively. Results indicated that aggregate size distribution of reclaimed tidelands and tidelands under various agricultural systems vary with reclamation period and soil type.