Results of Laboratory Studies of Strengthening Subgrade Soil with Modifier

Current modern trends in road construction are the increase in traffic intensity and the carrying capacity of motor transport, as well as the expansion of the road network, including local roads. These trends put forward the task of not only increasing the durability of road structures, but also the use of local materials and soils in the construction of highways. Several methods have been developed to strengthen the soils of the road base. A variety of surfactants, modifiers and additives are also produced to strengthen the roadbed. Many of them have not shown their effectiveness in practice. Therefore, there is a need for plenty laboratory and field studies on this topic. Laboratory studies were carried out to investigate the effect of the modifier on the roadbed soil. The type of soil and its maximum density were determined at optimal humidity. Based on this, cement and a modifier were introduced into the soil composition, density and compressive strength were determined. The results of a scanning electron microscope (SEM) were obtained to study the effect of the modifier on the roadbed soil. Laboratory studies and SEM-analysis have shown that the addition of a modifier to the soil leads to an increase in its maximum density, a significant increase in compressive strength and that the modifier serves to improve the binding properties by forming a crystalline bond with cement.