Study on geotechnical performance of high-grade highway subgrade applied with fly ash

The subgrade filling of high-grade highways requires a lot of earth and stone. If the use of fly ash is used for filling, the purpose of reducing the weight of the subgrade and consuming a large amount of industrial solid waste can be achieved. In order to ensure that fly ash has the possibility of filling, it is necessary to systematically study the road geotechnical properties of fly ash. In this paper, the low liquid limit silty silica-alumina fly ash is taken as the research object, and the road geotechnical properties of fly ash are studied through laboratory tests. The results of the compaction test show that the maximum dry density and optimum moisture content have an obvious linear relationship with the increase in the proportion of fly ash. Small, conducive to the stability of the roadbed. The shear strength of fly ash mainly depends on the internal friction angle, which is much larger than that of ordinary clay. The above test conclusions can provide reference for scientific and economical treatment of fly ash subgrade.