The Relationship Between Penetration Modulus And Rut Modulus

Different types of asphalt mixture are used to carry out rutting test and single axis penetration test. The results which are achieved from test compare the quality of the two methods, and establish a relevance to two kinds of test methods, finally guide the engineering application.AC-13, AC-16, AC-20three distributions in the asphalt mixture are used in this study. In each gradation, five compaction degrees and six proportions are used. Plate thickness uses5cm,6cm and7cm in turn, these three thicknesses are determined by the rutting test, and they are also the best thickness adapting to their biggest gradation nominal size. Each type of asphalt mixture in test is made into over parallel plates, one part of them are used in rutting test, the other part for penetration test. The height of the core sample specimens which are got in the plates are also verified effectively for the penetration test at the same time. Before rutting test and penetration test, standard deviation of VV of the parallel specimens is analyzed to ensure that two kinds of the result of the test are not influenced by the process and the specimen itself. Dynamic stability DS and shear strength S are acquired respectively in these two trials. And then the rut modulus EDS and penetration modulus Es are calculated in accordance with the above data. Analysing DS and S, the correlation is concluded in the rutting test and penetration test. Studying finds that when the degree of compaction is changed, two kinds of test methods reflect the mixture high temperature stability consistently. Along with the degree of compaction change, changing trend and the best compaction times are proved similar respectively.Proving that the both can be substituted each other. When proportion is changed, the rutting test is proved to be affected by the proportion seriously.Mixture at high temperature stability cannot be evaluated correctly and reasonable proportion can not be obtained. Meanwhile, penetration test is not affected by this change.Asphalt mixture at high temperature stability can be evaluated correctly, and the optimum proportion is achieved too. At the same time, DS is transformed into the rut modulus EDS, and the shear strength S is transformed into penetration modulus ES combining with the penetration depth h, inspecting to the above conclusion again.So the conclusion is drown that changing the compaction degree realizes the space pavement design rate and anti-rutting index, the two methods above can all be used to be tested. But changing oil-stone ratio makes pavement design space anti-rutting performance index come true, penetration test can better evaluation asphalt mixture at high temperature stability than rutting test. This conclusion can guide the engineering construction greatly.