Plasticity Index of Clay Shale Stabilized with Bledug Kuwu Mud and Asphalt Emulsion Syahril (a*), Khansa Nuansa Oktofani (a), Indra Noer Hamdan (b)
a) Master of Applied Infrastructure Engineering Study Program, Department of Civil Engineering, Politeknik Negeri Bandung, Indonesia
b) Departement of Civil Engineering, Faculty of Civil Engineering, Institut Teknologi Nasional, Bandung, Indonesia
Abstract
Soil conditions are pivotal in construction as they can influence the success or failure of a project. Prior to construction, a soil investigation is typically conducted to obtain essential soil parameters required for design, including the plasticity index (PI). This study investigates the enhancement of soil parameters through stabilization using a mixture of Bledug Kuwu mud and emulsion asphalt. According to a 2020 analysis by the Mineral and Coal Technology Laboratory Public Service Agency (TEKMIRA), Bledug Kuwu mud exhibits properties similar to those of fly ash and volcanic ash, both of which are known for their high silica content and pozzolanic characteristics akin to cement, making them suitable for soil stabilization. Phosphoric acid functions as a binder in this mixture due to its propensity to react with cations in soil minerals. The research involved mixing soft soil with Bledug Kuwu mud at varying percentages (6%, 10%, 14%, and 18%), with a constant asphalt emulsion concentration of 8% across all mixtures. The objective was to determine the optimal stabilization mixture for soil. Results demonstrated that the combination of Bledug Kuwu mud and asphalt emulsion effectively reduced the plasticity index, with the maximum reduction reaching 25.63%. The activity index (A) was measured at 0.07, indicating an inactive soil (A < 0.75). Consequently, the findings suggest that Bledug Kuwu mud and asphalt emulsion admixture is an effective method for soil stabilization.
