Determination of master curves for asphalt mixtures by means of IT-CY tests
The concept of ecologically conscious and energy saving roads must be expanded to the performance of the asphalt mixtures as well as to the test related to it. This paper investigates the tests focusing on a better description of the behaviour of asphalts as well as on a deeper revelation of the impact of different compositions. Based on the international experiences the recording of the asphalt´s complex module over the entire temperature range by the determination and evaluation of the mater-curves appeared as a possible solution for more precise description of the asphalt behaviour.
Influence of temperature distribution on the design of pavement structures
The bearing capacity of asphalt pavement structures is not constant due to the continuous change of temperature, and the importance of temperature change varies layer by layer. In the present article we reveal to what extent temperature change influences cumulated fatigue with the application of detailed pavement structure models and which seasons and parts of the day are significant in terms of fatigue. The pavement structure models were set up on the basis of stiffness tests performed in laboratory and on the data supplied by a temperature detector placed into a pavement structure. The set of data contains the results of measurements of one year with the measurement frequency of 10 minutes.
PHYSICAL PROPERTIES OF ASPHALT CEMENT AND THE DEVELOPMENT OF PERFORMANCE-RELATED SPECIFICATIONS
One of the primary objectives of the Strategic Highway Research Program (SHRP) is to develop performance-related specifications for asphalt cement. This paper describes the program of research that is being pursued by the authors to develop new or improved test methods and specification criteria that are suitable for the development of a performance-related specification for asphalt cement. This paper consists of six sections, each of which is relevant to the problem of developing more effective specifications for paving grade asphalts: (1) a review of asphalt rheology; (2) a brief discussion of the chemistry and microstructure of asphalt cement; (3) a review of the traditional methods of characterization; (4) a discussion of the shortcomings of current specifications; (5) a description of proposed test methods and specification framework; and (6) a final section in which the information presented in this paper is summarized, and a few important conclusions are made concerning the development of performance-related specifications for asphalt cement.