Simulation of Hourly Temperature Gradients in Asphalt Concrete PavementStructures

摘要

The design of overlays on existing pavements requires an understanding of thestrains at the overlay-base interface. The overlay, asphaltic concrete, is a highly temperature-sensitive viscoelastic material resulting in strains which are dependent upon the temperature profiles which exist in the asphalt layer as a result of varying weather conditions during the year. Therefore, the present study developed procedures which utilize yearly weather data obtained from the National Climatic Data Center to estimate the temperature profiles that affect the modulus of elasticity-temperature relationship. Additional input included many weather factors such as wind velocity, cloud cover, solar radiation, air temperature, latitude, longitude, and a host of other factors specific to a location and time of day. The procedures, or temperature simulations, utilize up to ten years of hourly weather data to develop the vertical and horizontal strains at the asphalt-base interface. These strains vary from hour to hour during the day and night as temperature gradients change. The results therefore are reported as density and cumulative probability histograms of strain magnitudes. Two models are presented to make these computations.