Increasing Dry Volume Weight of Poorly Graded Soil Using Recycled Concrete Aggregate (RCA) with Standard Proctor Test (SPT) Method

The land has a function as the basis for laying buildings. The unstable soil structure damages the buildings above it. Sandy loam soils are classified as unstable soils that are not affected by density. In addition, minimal density also affects the strength of the soil. This study aims to increase the dry volume of sandy loam soil. Experimental research was carried out through the process of soil compaction with the addition of waste concrete. Waste concrete added by 3, 5, 7, 9, 11, 13, and 15%. The dry volume weight value will be obtained through soil compaction, which is used as a correlation in the CBR design and later used as a parameter to prepare the road pavement subgrade. The results showed that the dry volume weight on SP soil could be increased using RCA by 13%. This is directly proportional to the CBR design value and can change the function path from sub-grade to sub-base in road construction planning to be able to estimate a thinner design penetration layer in the same class condition. From the results of this knowledge, it can be used to improve the quality of the soil as a road pavement layer.