Rheological properties of materials used in bridge asphalt pavement structures

Abstract

One of the elements that determine the durability of bridge structures is the bridge pavement. The durability of
bridge pavements depends on two main factors: traffic load and climatic conditions. Bridge deck surfaces might
exceptionally become exposed to extreme low and high temperature conditions. Stresses and strains in this type
of construction are different from those of the road surfaces located on the soil. Bituminous binders and asphalt
mixtures are thermoplastic components of waterproofing layers and surfacing. Their properties vary depending on
the temperature. This paper presents the laboratory test results of rheological properties of asphalt mixtures for
bridge pavements. The research plan included typically used asphalt mixtures - asphalt concrete (AC), stone mastic
asphalt (SMA) and mastic asphalt (MA). A new type of mixtures, stone mastic asphalt with high grit content SMAMA,
were also tested. Paper presents test procedure for determining the stiffness of asphalt mixtures on cylindrical
samples. Samples preparation and test method of direct tension–compression on cylindrical specimens (DTC-CY)
were discussed. The selected results of dynamic modulus and phase angle at different temperatures and varied
frequencies were presented. These parameters describe the visco-elastic properties which determine the durability
of bridge pavements. The results were presented as a leading curves, black curves and Cole-Cole graphs. A
comparison of the results of asphalt mixtures with the results of binder in dynamic shear rheometer DSR was
performed. The functional evaluation of the asphalt mixtures was extended for fatigue life test and rutting
resistance. The results of conducted research proved that the types of asphalt mixture affect the viscoelastic
properties and durability of bridge pavements.