The construction of road structures on soft soils is prone to structural damage due to the low bearing capacity of the soil under the load imposed by vehicles. Chemical stabilization is a popular method used to increase the bearing capacity of soft soils. This study aims to examine the effectiveness of soft soil stabilization using a mixture of lime, nickel slag, and aluminium hydroxide to enhance soil bearing capacity. The addition of lime as a binding agent is expected to reduce plasticity and increase soil strength, while nickel slag and aluminium hydroxide serve as additives that improve overall stabilization performance. The California Bearing Ratio (CBR) laboratory test was conducted by varying the proportions of stabilizing materials relative to the weight of the soft soil at its optimum moisture content. The lime addition variations used in this study were 2%, 4%, and 6%. The results showed that the lime, nickel slag, and aluminium hydroxide stabilization mixture significantly improved the soil's bearing capacity compared to untreated soil or soil stabilized only with nickel slag. The CBR value for soil stabilized with nickel slag, aluminium hydroxide, and lime reached 37.78% after 28 days of curing. This value is 7.6 times higher than that of natural soil and 1.3 times higher than soil stabilized with nickel slag alone. Thus, the use of a mixture of lime, nickel slag, and aluminium hydroxide is an effective method for increasing the bearing capacity of soft soils, making it applicable for road construction on soft soils requiring enhanced load-bearing capacity.

Soil stabilization, lime, nickel slag, aluminium hydroxide, soil bearing capacity, soft soil

W.-H. Yuan, H.-C. Wang, Y.-J. Li, W. Zhang and K. Liu, "Large deformation assessment of the bearing capacity factor for rigid footing : effect of soil heterogeneity," Computational Particle Mechanics, no. https://doi.org/10.1007/s40571-024-00763-6, 2024.

B. M. Das, Advanced in Soil Mechanics, New York: Taylor & Francis, 2008.

N. A. Hasan, H. A. Ahmed and I. S. Hussein, "Enhancing the Characteristics of Gypsum Soil by Adding Hydrated Lime and Cement," Revue des Composites et des Matériaux Avancés, no. https://doi.org/10.18280/rcma.340210, pp. 207-214, 2024.

A. Firozi, "Fundamentals of Soil Stabilization," International Journal of Geo-Engineering, vol. 8, no. 26, https://doi.org/10.1186/s40703-017-0064-9, 2017.

C. Shi, A. F. Jiménez and A. Palomo, "New cements for the 21st century: The pursuit of an alternative to Portland cement," Cement and Concrete Research, no. https://doi.org/10.1016/j.cemconres.2011.03.016, 2011.

M. J. Roshan and A. S. B. A. Rashid, "Geotechnical characteristics of cement stabilized soils from various aspects: A comprehensive review," Arabian Journal of Geosciences , vol. 17, no. 1, https://doi.org/10.1007/s12517-023-11796-1, 2023.

A. A. Amadi and A. Okeiyi, "Use of quick and hydrated lime in stabilization of lateritic soil: comparative analysis of laboratory data," International Journal of Geo-Engineering, vol. 8, no. 3, https://doi.org/10.1186/s40703-017-0041-3, 2017.

I. Rauf, H. Heryanto, D. Tahir, A. Abd Gaus, A. Rinovian, K. Veeravelan, A. Akouibaa, R. Masrour and A. Akouibaa, "Uncovering the potential of industrial waste: turning discarded resources into sustainable advanced materials," Physica Scripta, vol. 9, no. 6, DOI 10.1088/1402-4896/ad4ad1, 2024.

I. Rauf, A. Gaus, M. A. Sultan, Heryanto and Heryanto, "Analysis and Characterization of Nickel Industry By-Products as Pozzolan Materials," Civil Engineering and Architecture, vol. 12, no. 1, DOI: 10.13189/cea.2024.120130, pp. 401-408, 2024.

J. Nelson and D. Miller, Expansive Soils: Problems and Practice in Foundation and Pavement Engineering, New York, USA: John Wiley and Sons, 1997.

F. Bell, "Lime stabilisation of clay soils.," Bulletin of Engineering Geology & the Environment, vol. 39, no. 1, 10.1007/BF02592537, 1989.

M. M. Mubeen, "Stabilization of soft clay in irrigation projects," Irrigation and Drainage, vol. 54, no. 2, https://doi.org/10.1002/ird.165, pp. 175-187, 2005.

E. Vitale, D. Deneele and G. Russo, "Microstructural Investigations on Plasticity of Lime-Treated Soils," Minerals, vol. 10, no. 5, https://doi.org/10.3390/min10050386, p. 386, 2020.

P. Lindh and P. Lemenkova, "Dynamics of Strength Gain in Sandy Soil Stabilised with Mixed Binders Evaluated by Elastic P-Waves during Compressive Loading," Materials, vol. 15, no. https://doi.org/10.3390/ ma15217798, 2022.

F. Wang, H. Wang, F. Jin and A. Al-Tabbaa, "The performance of blended conventional and novel binders in the in-situ stabilisation/solidification of a contaminated site soil," Journal of Hazardous Materials, vol. 285, no. https://doi.org/10.1016/j.jhazmat.2014.11.002, pp. 46-52, 2015.

A. Shvarzman, K. Kovler, I. Schamban, G. Grader and G. Shter, "Influence Of Chemical And Phase Composition Of Mineral Admixtures On Their Pozzolanic Activity," Advances in Cement Research, no. DOI: 10.1680/adcr.2002.14.1.35, pp. 35-41, 2002.

O. Carașca, "Soil improvement by mixing: techniques and performances," Energy Procedia, no. https://doi.org/10.1016/j.egypro.2015.12.277, pp. 85-92, 2016.

M. F. Noaman, M. A. Khan, K. Ali and A. Hassan, "A review on the effect of fly ash on the geotechnical properties and stability of soil," Cleaner Materials, vol. 6, no. https://doi.org/10.1016/j.clema.2022.100151, 2022.

A. Gaus, I. Rauf, F. Siregar and H. Heryanto, "Proximity Porosity and Crystallinity Analysis as Clay/Nickel Slag Characteristics for Material Stabilization Application," Trends In Sciences, vol. 21, no. 8, DOI: https://doi.org/10.48048/tis.2024.7970, 2024.