| In fact, the pavement structure is acted by the continual changes factors, such as vehicle, climate, and cultural, the actual working condition of the pavement, include mechanical model and nature of the material have great gap with the existing static mechanical system. With the development of the design of international pavement structure, pavement design changes from static to dynamic is an inevitable trend, pavement materials dynamic modulus replace static modulus is the foundation, and is also the first step. Therefore, it is very necessary and meaningful to study the characters and changes law of the asphalt mixture under dynamic loads, and determine its test methods and test their model value.Based on investigation and research on many asphalt mixture dynamic modulus tests in international and domestic; this paper puts forward a set of experimental methods of the dynamic modulus, fitting to our country conditions. And analyzes and studies the feasibility, influencing factors (stress level, specimen porosity, loading frequency, temperature, etc.) of these methods. Finally, according to analyzing the results, the relationship between dynamic modulus and static modulus of asphalt mixture, the regression formula of dynamic modulus of asphalt mixture, and various asphalt mixture dynamic modulus of value are put forward.First, based on the research of the basic theory of asphalt mixture, analyze the asphalt mixture viscoelastic properties, thus leads to the concept of asphalt mixture dynamic modulus, and then make some preliminary study of principle of equivalent of time-temperature and equivalent of temperature-frequency;Secondly, some experimental research of the asphalt mixture of static modulus, and some preliminary study of the rationality of the value of static modulus are researched; thirdly, on asphalt mixture static modulus of a pilot study static modulus value of the nature and scope of reasonable value are discussed for preliminary;Finally, UTM test system are used to do the experiment of dynamic modulus test for different temperatures and frequencies of several typical asphalt mixture, get the value and analyze the factors which influent the dynamic modulus, receive the scope of of the asphalt mixture dynamic modulus, in according with the results of the theoretical analysis, we get relationship between dynamic modulus and static modulus, and then get the reunification formula of asphalt mixture dynamic modulus. |
