These design methods have been historically found to be generally reliable and reasonable for most application in design. However, premature distress in many flexible pavements suggests that these empirical methods of de-sign do not guarantee a stable mix. Recently, many studies have been carried out in order to develop a rational mix design procedure that accounts for both the mix volumetric properties as well as fundamental engineering properties. Such a test is currently absent in the existing Superpave approach. The new procedure introduces the flow time as a fundamental engineering design criterion in the mix design.
Plastic flow occurs when the deformation occurs at no volume change.
The creep test required to evaluate the mix stability is simple, quick, economical, and practical from the industry point of view. It has been carefully designed so that the input files are human readable and consist of a friendly, intuitive syntax rather than a table of numbers. Engineers are provided with the flexibility to modify problem parameters and problem solving algorithms without having to recompile source codes. Shear effects are an important displacement component in base-isolated highway bridge structures. Six major steps were followed in completing the research.