PURPOSES : So far, aged cement concrete pavement on express highways has been rehabilitated mainly with asphalt concrete inlay. However, potholes were the major problem, and they shortened the life of the inlay mainly owing to the poor drainage of water once it infiltrated the interface of the concrete and asphalt. The purpose of this study is to compare the performance and economic efficiency of asphalt overlay and inlayMETHODS: Overlay and inlay were compared through accelerated pavement testing, and a life-cycle cost analysis was conducted in this study using the CA4PRS program.RESULTS and CONCLUSIONS : It was found from accelerated pavement testing that the overlay exhibited reflective crack resistance that was more than twice as effective as that of inlay. The total cost (construction cost + user cost) within the analysis period (20 years) of the overlay was 37% lower than that of the inlay.

This paper concerned with design of constant stress accelerated lift test(ALT). Becase a major factor to affect a life of automotive V-ribbed belts is a temperature, we selected a temperature as a accelerated fator to perform a test. Acclelerated life test plans were developed with the assumption of weibull lifetime distribution. The genreal value of beta parameter was accepted in this life test (β=1.1). The sample number was calculated by alpha parameter which was induced by beta.