Investigation of rheological behaviours of dense bituminous mixtures with polypropylene fiber in repeated creep test

In recent years, traffic volumes are apparently increased in our country and world. Because of this, manufacturing of rigid pavements, which is better and stronger, showed an increase especially in USA and Canada and in other European countries. Because of the fact that asphaltic pavements are really important in the pavement engineering, many researches are carried out in the case of strengthening hot bituminous mixtures. For this purpose, modification of bituminous hot mixes was started with chemical additives such as polypropylene, rubber, waste rubbers etc. In this thesis, first, Marshall test is conducted on various pure mixes and polypropylene fiber additive mixes. In this test, optimum bitumen content for pure mixes; optimum polypropylene fiber type, addition content and optimum bitumen content for polypropylene fiber additive mixes are determined. Second, repeated creep test is conducted on all mixes that are prepared with optimum values. Marshall test showed that the optimum bitumen content is %5 for pure mixes. Marshall test also showed that optimum polypropylene fiber type is M-03, addition content is %o3 and optimum bitumen content is %5 for polypropylene fiber additive mixes. Between %12 and %40 increases are observed on additive mixes at the end of the Marshall tests. It is shown that polypropylene fibers increased service life of samples seriously. In addition, it is observed that there are important effects of loading force, loading and rest times on service life of samples. Keywords: Bitumen, Repeated Creep Test, Polypropylene Fiber, Modified Bitumen, Marshall Test