| As the rapid development of road construction in China, the construction of highway network has reached an unprecedented height. After many years’service, although with good integrated intensity, the current asphalt concrete roads have surface and function problem which would lead to structural damage, thanks to preventive maintaining measurements, this problem can be eliminated, and long life asphalt pavement (LLMO) is a kind of brand new technology that has already been applied in some projects in America. According to the result of a tracking survey, for roads with medium or lower traffic, the service life of LLMO is above10years, which is much longer than that of asphalt concrete ultra-thin overlay usually used in micro-surfacing and slurry seal. Moreover, the technology may have positive effect to the recovery of pavement structural performance. The main factors which influence the service life of LLMO are material performance, traffic load and interfacial combining wear under the comprehensive function of temperature change. Currently, the research results are mainly about outdoor and indoor experiments without systematical mechanical analysis. My research established a numerical model with the help of ABAQUS finite element analysis software and simulated mechanical behaviors of micro-overlay and pavement under load conditions and temperature change.This paper first makes a detailed introduction to micro-overlay technology and its application. Experiment result of micro-overlay technology showed that the service life of micro-overlay is more than10years for roads with medium or lower traffic, and this characteristic is closely related to material performance and joint stress among layers. Chapter3in this paper describes the establishment of pavement mechanics finite element analysis model at ordinary temperature after the technology was applied and make an analysis of sensitivity, which make a comparison analysis of pavement stress response under situations of overload, climbing and swerve so as to confirm the most disadvantage. The result showed that there will be the most obvious stress response under the condition of200%overload. Chapter4describes the establishment of mechanics analysis model under temperature change, which makes further numerical simulation analysis combined with real temperature condition and load condition. The result showed that compared to constant temperature model without considering temperature change, vertical compressive stress, longitudinal shear stress and transverse shear stress were all increased. Therefore, temperature change has a great impact to the service life and inter-layer durability of micro-overlay and will aggravate pavement damage and shorten the service life of pavement after the application of micro-overlay technology. |
