FEASIBILITY STUDY OF MOUNTAIN MATERIAL AS CLASS B AGGREGATE FOUNDATION LAYER FOR HIGHWAY FLEXIBLE PAVEMENT

Abstract

This study aims to examine the technical feasibility of the Wae Lengkas Quarry mountain material as a Class B Aggregate Foundation Layer for flexible road pavements. Material samples were taken from the quarry and then tested in the Civil Engineering Laboratory of the Catholic University of Indonesia St. Paulus Ruteng. The test results were compared with the 2018 General Specifications for Roads and Bridges which regulate the quality standards for road materials. The types of tests carried out are grain size distribution, wear, light density and Atterberg limits. From the results of the grain size test, the percentage of sand was 93%, clay 1.5% and salt 5.47%. Based on the percentage of the grain division, the Wae Lengkas Quarry material is included in the sand in the USDA (U.S. Department of Agriculture) triangle chart. The liquid limit (LL) value is 32%, the plastic limit (PL) is 26.74% and the plasticity index (PI) is 5.26% which is the difference between the liquid limit and the plastic limit. Based on the Atterberg limits value, the material is feasible because the B value < 35 and PI < 10. Specific gravity (Gs) 2.5 gr/cm3, maximum dry unit weight 1.62% at optimum water content 13.45% and abrasion value 46.28%. Based on the abrasion value, the material is not suitable as Class B Aggregate because it is > 40%. This shows that the Wae Lengkas Quarry material cannot be used directly as Class B aggregate but must be mixed with gravel from other quarries that meet the abrasion value.