PURPOSES : The purpose of this study was to reduce greenhouse gases and prevent potholes on roads by evaluating the performances of hot and warm mixed asphalt mixtures. METHODS : Quality tests were conducted using an appropriate aggregate ratio of the asphalt mixture. The tests for comparing the warm mixed asphalt mixture are the indirect tensile strength and toughness, Marshall stability and flow, tensile strength ratio, and dynamic immersion test. A performance evaluation was conducted using a mixture that satisfied the quality test results. A performance evaluation test was also conducted using the dynamic modulus and Hamburg wheel tracking test. To analyze the performance based on the amine content, the performance was compared with that of a hot mixed asphalt mixture. RESULTS : All tests for the mixture results satisfied the standard values. The optimal amine content was analyzed through the high and low frequencies of the dynamic modulus test results and stripping inflection point with the final rut depth of the Hamburg wheel tracking test. The dynamic modulus test results demonstrated better crack resistance and plastic deformation when a high amine content ratio was used. The Hamburg wheel-tracking test showed water resistance and plastic deformation resistance. The test results of the Hamburg wheel tracking indicated better deformation resistance and water resistance when a high amine content ratio was used. CONCLUSIONS : The plastic deformation and crack resistance increased with an increase in amine content. Analysis of the comprehensive test revealed that the optimal amine content was between that of additives B(50%) and C(65%). Tests with a granular amine content are planned to confirm the specific components. Also planned are a simplified viscoelastic continuum damage test and a semicircular bending test to evaluate the performance better.

PURPOSES : Preventive pavement maintenance is an economical and efficient method of infrastructure management. This study aims to improve the performance of cold thin-layer asphalt pavement, which is mainly used in earthwork pavement, and for bridge overlays and structures. METHODS : A cold asphalt mixture of modified emulsified asphalt and RAP was prepared for cold recycled thin-layer asphalt pavement. The performance of the mixture as a function of fiber reinforcement to improve flexural strength and crack resistance was evaluated. RESULTS : The use of RAP aggregate in cold asphalt mixture was found to increase the cohesive strength of the mixture and improve the wet abrasion resistance due to the effect of the residual binder. As a result of the loaded wheel test and flexural tension test with the addition of fiber reinforcement, it was found that the crack resistance of 0.4 % glass fiber was the best, and especially, the flexibility at low temperature was excellent. CONCLUSIONS : The cold recycled thin-layer asphalt pavement mixture has improved cohesive strength, flexural strength, and crack resistance compared to existing cold asphalt pavement materials, so it will contribute to economical and effective maintenance in preventive maintenance of bridge overlays and structural pavements.