Bearing Capacity Improvement of Expansive Soil: Stabilization with Cement and Iron Oxide Additive

Abstract

This research is intended to increase the bearing capacity and durability of expansive clay subgrade with Portsoil Composite Cement (PCC) and Iron Oxide additives. Using two variants of the stabilization material composition; composition-1 is soil with 5% of PCC, and composition-2 is soil with 5% PCC + 0. 04% Iron Oxide). Tests include swelling potential, durability, and CBR (California Bearing Ratio). The test results showed that the performance of stabilization using composition-2 was able to reduce swelling potential on day 3 by 94. 44% (14. 44% greater than using composition-1), reducing the potential for volume increment by 94. 15% (greater 15. 02% compared to using composition-1) and weight to 93. 31% (15. 32% greater than using first). The highest CBR value in the 3 wet-dry cycle periods was nature soil 2. 32%, using composition-1 reached 25. 26%, while using composition-2 reached 36. 93% (11. 67% greater than CBR value using composition-1). That the addition of 0. 04% Iron Oxide to PCC-soil stabilization can significantly improve cement performance for expansive clay stabilization as a road subgrade.