الفهرس | Only 14 pages are availabe for public view |
Abstract The ability to characterize asphalt pavement materials ill terms of fundamental properties, such as tensile strength, is becoming important. This is partially due to the fact that many agencies are beginning to use pavement design systems based on elastic or viscoelastic theory. The use of empirical tests failed to provide the elastic or viscoelastic properties required by these design procedures and generally cannot be used to evaluate new materials, such as recycled asphalt mixtures and modified asphalt mixtures. In addition it can not be used to evaluate the material properties related to distress modes such as: Thermal or shrinkage cracking, fatigue cracking, and permanent deformation, or rutting .After studying of previous researches in the indirect tensile strengtb . It have been found that different factors were affected this stresses . laboratory test programme depend on test all the specimen in both the Indirect tensile test and Marshall test at the same time for all the mixes used in the research and by the same specimen shape ( Marshall specimen) at different variables which affect the test results. The research studied the variable factors ( type of aggregate, aggregate shape and aggregate gradation ) on the tensile strength where the other factors like test temperature , bitumen type, loading rate ..ect were fixed. after making the analysis a limited values have been estimated for the tensile strength for the Egyptian most familiar mixes used .The results indicate that Dolomit, Limestone aggregate is the best aggregate for tensile and the rounded aggregate shape also is the best for tensile. |