Feasibility of Siliceous Sandstone Utilization in Porous Asphalt Mixture

In this paper, the feasibility of using siliceous sandstone aggregate in porous asphalt mixture porous asphalt concrete (PAC)-16 was studied. The gradations of siliceous sandstone and limestone PAC-16 mixtures were calculated by the backward regression method and asphalt contents were obtained by the Schellenberg leakage test and Cantabro scattering test. The void rate attenuation, gradation refinement, mechanical properties, and road performances of sandstone and limestone PAC-16 mixtures were tested and compared. Result shows that under the same load, the attenuation of total and connected void rates of sandstone mixture are less, and the mass percentage variation of aggregate in each grade in a sandstone mixture under repeated load is smaller. A sandstone mixture has similar mechanical properties as a limestone mixture with a lower void rate, and it has better mechanical properties compared with limestone mixture with a similar void rate. Compared with a limestone mixture, a sandstone mixture has better permeability and high-temperature performance, close low-temperature performance, and slightly worse moisture stability. Therefore, a sandstone mixture could not be applied in winter frost areas to reduce freeze-thaw cycling, and it could be applied in single-layer drainage pavement with low traffic volume or in the lower layer of double-layer drainage pavement to avoid direct contact with traffic loads. The addition of an antistripping agent is strongly recommended.