Characterization of Crushed Rock-Concrete Interface Behavior through the Parallel Gradation Technique

The response of a soil-structure system subjected to monotonic or cyclic loading is influenced significantly by the mechanical behavior of soil-structure interface. In this paper, the friction characteristics of the crushed rock-concrete interface and the role of the crushed rock deformability were examined through a series of monotonic and cyclic direct shear tests. The physical modeling technique of parallel gradation was adopted where two parallel gradation curves of the crushed rocks were prepared and used in the tests. The tests were carried out in dry condition and with two initial void ratios representing both loose and dense states. Two concrete interfaces of different roughness were used in the interface direct shear tests. The validity of the physical modeling technique of parallel gradation is also discussed.