A mixture of sandstone and mudstone particles is often used as the main filling material for many agriculture-related and civil engineering projects, including rock-fill dams and foundations. The long-term rheological deformation experienced by rock-fill dams and foundations filled with this mixture is much bigger than that of coarse-grained and cohesive soils, due to the deterioration and softening of the mudstone particles. This study focuses on the rheological deformation of a sandstone-mudstone particle mixture, prepared by mixing sandstone and mudstone particles, based on the content by weight of four mudstone particle types. Confined uniaxial compression tests were performed to test the rheological deformation of 24 samples of the mixture, and a stress-strain curve was obtained for each test. On the basis of compression curves, the rheological process of the mixture was divided into four phases: linear, attenuation rheological, secondary attenuation rheological and stable phases. The three defining features of the curve, namely the rheological attenuation factors, attenuation rheology critical strain and limited rheological strain, were then determined and modeled. A segmented rheological model was then proposed, based on a modified attenuation rheological constitutive model for coarse-grained soil. The modelled results compared well with the experimental data, and the modelled compression-curve prediction was able to describe the two-stage attenuation rheology features (attenuation rheological and secondary attenuation rheological phases) of the sandstone-mudstone particle mixture.

It is known that the properties of asphalt-aggregate adhesion show great effect on the performance of asphalt pavement, while the temperature plays an important role in determining the fundamental properties of asphalt binder between single aggregate-aggregate contacts surfaces. The temperature sensitivity is considered to be very important on understanding the failures of asphalt pavement, especially on the asphalt-aggregate adhesion. Knowledge the temperature sensitivity of asphalt-aggregate adhesion is very important in asphalt mixture design. The purpose of this paper was to quantify the effect of temperature on the adhesion and cohesion of asphalt film between aggregate and asphalt. The adhesive/cohesive failure of asphalt film between single aggregate-aggregate contacts was investigated using dynamic mechanical analyzer under dynamic tension stress test with force-control mode, then fracture surface were analysis by a Polarizing Microscope. Contrastive experiments were conducted on SBS modified asphalt under different temperatures. Experimental results indicate that the area percentage of adhesive failure was decreased with the increase of test temperature. And the adhesive failure percentage is enhancing with the increase of loading max-stress level.

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Montmorillonite (MMT), a typical layered silicate, has been widely used to prepare modified asphalt. This paper investigates the high temperature performance and low temperature property on layered silicate modified asphalt concrete. The control concrete is prepared by base asphalt. Meanwhile, three-point bending, conventional and SHRP rutting tests are used to compare the properties of the two types of asphalt concrete. The results of conventional and SHRP rutting tests show that the modified asphalt concrete exhibits a better high temperature performance than the control concrete. And the maximum bending strength of modified asphalt concrete is higher than that of control concrete at the same temperature. It can be concluded that both the high temperature performance and low temperature property of asphalt concrete has been improved efficiently by utilization of layered silicate modified asphalt.