Abstract: Study on the dynamic mechanical properties of hydraulic asphalt concrete under compression-shear load is important to ensure the safe operation of asphalt concrete core wall earth-rock dams. In this paper, we use an independently-developed compression-shear test device to study the dynamic mechanical properties of hydraulic asphalt concrete at different shear rates (0.0005 s-1, 0.001 s-1, 0.005 s-1 and 0.01 s-1) under different temperatures (5 °C and 15 °C) and different normal stresses (1 MPa, 2 MPa and 3 MPa). The results show that each specimen has obvious characteristics of oblique shear failure, and different normal stresses or shear rates impose an impact on its failure mode and shear stress-strain curve to different degrees. With increasing the normal stress or shear rate, shear strength and shear modulus increase; peak strain increases with the decreasing normal stress or increasing shear rate. Using the Mohr-Coulomb criterion, we obtain the laws of two strength parameters－cohesion c and internal friction angle φ of hydraulic asphalt concrete－varying with shear rate.

Key words: hydraulic asphalt concrete, compression-shear action, failure mode, dynamic mechanical property, Mohr-Coulomb criterion