Measuring and Evaluating Modulus of Elasticity of Asphalt Mixtures Using Plastometer.

Document Type : Research Studies

Authors

1 Highway and Traffic Engineering., Cairo University., Egypt

2 Highway and Traffic Engineering., Zagaig University., Zagaizg., Egypt.

3 Highway and Traffic Engineering., Cairo University., Egypt.

Abstract

It is of a great impc.tance in the design of asphalt mixtures to know their modulus of elasticity. The common laboratory tests used for measuring the resilient modulus are very sophisticated and complicated. Radonesky (A Russian pavement material researcher) suggested and prepared a simple device called "plastometer" to be used in measuring device (plastometer) for measuring modulus of elasticity of asphalt mixes in Egypt. The study aims also to search the different factors affecting the values of modulus of elasticity as well as finding the possible relationships between the different traditional methods used to determine this modulus and the plastometer test procedure. These methods include Van der Poel, dynamic stability, and Marshall stiffness. To achieve the study objectives a comprehensive experimental program is carried out on limestone-asphalt mix under different conditions including mix gradation, mixing procedure, and testing temperature. The experimental program passes through two main phases. The first phase is conducted on one mix having the same material properties and mixing procedure at different testing temperatures to check the validity of using plastometer in measuring modulus of elasticity for asphalt mixes. While, the second phase is directed to find possible relations between the results of the different methods used to determine the modulus of elasticity. Based on the study results, it can be concluded that plastometer test results can be used satisfactorily in determining modulus of elasticity of asphalt mixtures. Valuable relationships are found between the different methods used in calculating modulus of elasticity and the plastometer method.

Main Subjects