Stabilization of clayey soils contaminated with lead and zinc nitrate using metakaolin geopolymer

Document Type : Research Article


1 Department of Civil Engineering, Islamic Azad University, Central Tehran Branch

2 Department of Civil Engineering, , Islamic Azad University, Central Tehran Branch


One of the most important environmental problems humans face is soil pollution, which occurs in various factors and affects different soil parameters. one way to tackle this phenomenon is the stabilization of soils. This study presents the result of using metakaolin geopolymer to stabilize contaminated clay. In this study, the primary and contaminated soil without stabilizing are subject to various tests; The results of the first phase of the experiments showed that increased contamination concentration had a negative effect on soil parameters. The results of these experiments also showed that the most critical concentration of soil contamination was among the concentrations of 10000 ppm. Then the soil contaminated with the most critical concentration was stabilized by metakaolin geopolymer at 5, 10, and 15% weight and was re-tested and identified with various resistive in 7 days of curing time. Finally, the results achieved at this stage showed that by increasing the percentage of metakaolin geopolymer, the soil strength parameters have significantly increased, and the addition of geopolymer to contaminated soil of 10000 ppm has resulted in the stabilization of soil and improved soil properties. The results of the experiments showed that the most optimal state was the addition of 15% metakaolin geopolymer to the 10000 ppm contaminated soil, in which the liquid limit increased by 39.47%, the plastic limit increased by 51.06%, the plasticity index increased by 20.68%, the optimal moisture content increased by 19.84%, Dry Unit Weight decreased by 3.23%, unconfined compression strength increased 2.28 times and CBR increased 2.31 times, compared to the unstabilized 10000 ppm contaminated soil.


Main Subjects

[1] V.R. Ouhadi, M.S. Fakhimjoo, S.T. Omid Naeini, The Comparison of Plastic and Permeability Behavior of Bentonite in the Presence of Organic and Heavy Metal Contaminants, Journal of Civil and Environmental Engineering, 46(85) (2017) 25-36.
[2] Y. Chu, S.-y. Liu, G.-j. Cai, H.-l. Bian, A study in the micro-characteristic and electricity properties of silt clay contaminated by heavy metal zinc, Japanese Geotechnical Society Special Publication, 2(14) (2016) 556-559.
[3] Y. Chu, S. Liu, F. Wang, G. Cai, H. Bian, Estimation of heavy metal-contaminated soils’ mechanical characteristics using electrical resistivity, Environmental Science and Pollution Research, 24(15) (2017) 13561-13575.
[4] J. Park, Assessment of shear strength characteristics and zinc adsorption capacities of zeolite-amended soils for adsorptive fill materials, 서울대학교 대학원, 2017.
[5] M. Karkush, T. Al-Taher, Geotechnical evaluation of clayey soil contaminated with industrial wastewater, Archives of civil engineering, 63(1) (2017).
[6] A.O. Abidoye, O.D. Afolayan, I.I. Akinwumi, Effects of lead nitrate on the geotechnical properties of lateritic soils, International Journal of Civil Engineering and Technology, 9(7) (2018) 522-530.
[7] S. Contessi, L. Calgaro, M.C. Dalconi, A. Bonetto, M.P. Bellotto, G. Ferrari, A. Marcomini, G. Artioli, Stabilization of lead contaminated soil with traditional and alternative binders, Journal of hazardous materials, 382 (2020) 120990.
[8] S. Contessi, M.C. Dalconi, S. Pollastri, L. Calgaro, C. Meneghini, G. Ferrari, A. Marcomini, G. Artioli, Cement-stabilized contaminated soil: Understanding Pb retention with XANES and Raman spectroscopy, Science of The Total Environment, 752 (2021) 141826.
[9] F. Wang, J. Xu, H. Yin, Y. Zhang, H. Pan, L. Wang, Sustainable stabilization/solidification of the Pb, Zn, and Cd contaminated soil by red mud-derived binders, Environmental Pollution, 284 (2021) 117178.
[10] P. Pei, Y. Sun, L. Wang, X. Liang, Y. Xu, In-situ stabilization of Cd by sepiolite co–applied with organic amendments in contaminated soils, Ecotoxicology and Environmental Safety, 208 (2021) 111600.
[11] K. Wianglor, S. Sinthupinyo, M. Piyaworapaiboon, A. Chaipanich, Effect of alkali-activated metakaolin cement on compressive strength of mortars, Applied Clay Science, 141 (2017) 272-279.
[12] A. Al-Swaidani, I. Hammoud, A. Meziab, Effect of adding natural pozzolana on geotechnical properties of lime-stabilized clayey soil, Journal of Rock Mechanics and Geotechnical Engineering, 8(5) (2016) 714-725.
[13] P. Ghadir, N. Ranjbar, Clayey soil stabilization using geopolymer and Portland cement, Construction and Building Materials, 188 (2018) 361-371.
[14] K. Harichane, M. Ghrici, S. Kenai, Stabilization of Algerian clayey soils with natural pozzolana and lime, Periodica Polytechnica Civil Engineering, 62(1) (2018) 1-10.
[15] S.D. Khadka, P.W. Jayawickrama, S. Senadheera, B. Segvic, Stabilization of highly expansive soils containing sulfate using metakaolin and fly ash based geopolymer modified with lime and gypsum, Transportation Geotechnics, 23 (2020) 100327.
[16] Z. Rong-rong, M. Dong-dong, Effects of curing time on the mechanical property and microstructure characteristics of Metakaolin-based geopolymer cement-stabilized silty clay, Advances in Materials Science and Engineering, 2020 (2020).
[17] S. Othman, J.M. Abbas, Stabilization Soft Clay Soil using Metakaolin Based Geopolymer, Diyala Journal of Engineering Sciences, 14(3) (2021) 131-140.
[18] S. Wang, Q. Xue, Y. Zhu, G. Li, Z. Wu, K. Zhao, Experimental study on material ratio and strength performance of geopolymer-improved soil, Construction and Building Materials, 267 (2021) 120469.
[19] Y. Luo, J. Meng, D. Wang, L. Jiao, G. Xue, Experimental study on mechanical properties and microstructure of metakaolin based geopolymer stabilized silty clay, Construction and Building Materials, 316 (2022) 125662.
[20] J.-s. Li, Q. Xue, P. Wang, Z.-z. Li, Effect of lead (II) on the mechanical behavior and microstructure development of a Chinese clay, Applied Clay Science, 105 (2015) 192-199.
[21] Y.-J. Sun, J. Ma, Y.-G. Chen, B.-H. Tan, W.-J. Cheng, Mechanical behavior of copper-contaminated soil solidified/stabilized with carbide slag and metakaolin, Environmental Earth Sciences, 79(18) (2020) 1-13.