Permeability study of asphalt mixtures using falling head flexible side wall method

The durability of asphalt mixtures was strongly influenced by their permeability. By using self-made falling head flexible side wall device to gain permeability coefficients, the permeability behavior of three types of asphalt mixtures was investigated. By fitting the permeability coefficients gained by the above method and the air voids gained by using vacuum sealing method, the results showed: For Stone Matrix Asphalt(SMA)-13, Asphalt Concrete(AC)-16 and AC-20, the critical efficient Volume of Air Voids (VVe) contents are 7~9 percent, 7~10 percent and 8~10 percent, and the critical efficient Volume of Air Voids (VVvac) contents are 9~12 percent, 9~12.5 percent and 9~11.5 percent, respectively. By the above research, it is concluded that this self-made falling head flexible side wall device is effective to prevent water from side seepage and it is reliable for s indoor or field gained specimens 100mm in diameter.