Estabilización de suelos arcillosos de Macas con valores de CBR menores al 5% y límites líquidos superiores al 100%, para utilizarlos como subrasantes en carreteras

Abstract

The city of Macas and in general the east of Ecuador presents displays floors with very singular characteristics that make them subgrade not suitable for roads. Usually when a road in eastern Ecuador crosses this type of soil, these are replaced in their totality by materials of better quality. This process entails high investment and time. The present research intends to use new alternatives to improve the natural soil and in this way eliminate the replacement of the same and the reduction of the costs of construction. A method of soil improvement is proposed through the addition of quicklime to the natural soil. Is working with a soil found during work on the newly constructed side passage in the city of Macas. The soil presents a liquid limit of more than 100% water content greater than 140%, significant changes in its plastic range according to the type of drying that is used; the soil responds with CBR less than 5%. The soil response to lime treatment in the laboratory is analyzed. Was worked with 10, 20, 30 and 40% lime with respect to the dry weight of the material. The results indicate decrease of: liquid limit, plastic index and expansion; at the same time as the CBR increases. With the results obtained a value of 16% of lime is approaching. Using the properties of the soil treated with 16% of lime, a theoretical analysis of design and costs is carried out. The objective is to compare the design and costs of a flexible pavement using lime-treated soil and the traditionally used alternative. The results indicate a decrease in the cost of the highway if a treatment with lime could be used instead of the replacement of material. The present research presents an alternative to improve highly plastic soils and turn them into acceptable soils for road subgrade. Laboratory tests show the usefulness of the treatment and theoretical analyzes indicate a possible decrease in the costs of flexible pavements; however, a study of the applicability of the treatment to field conditions and the behavior of the stabilized soil in the long term is required.