RESEARCH ON APPLICABILITY NATURAL RED SAND FOR THE SUBGRADE OF HIGHWAY CONSTRUCTION BY EXPERIMENT IN THE LABORATORY

Abstract

This article presents some typical physical and mechanical characteristics of natural red sand collected in Thien Nghiep commune, Phan Thiet city, Binh Thuan province through static experiments in the laboratory. From the obtained results, it is shown that this sand belongs to group A-2 according to the AASHTO M145 standard on grain composition. The sand has a relatively high cohesion with an average value of about 29 kPa and the internal friction angle with an average value of about 35º which characterize the shear resistance of material. The CBR value of sand at a relative compaction of 0.95 is 20.67% which meets the requirements of subgrade materials for highway traffic construction according to current standards. Thus, through a series of static experiments, it is confirmed that this type of sand is potentially suitable as a subgrade material for traffic construction in Vietnam.