1. Introduction

The correct disposal of mine tailings in tailings ponds and mine waste landfills is becoming more critical [1, 2]. On the one hand, this is due to the increasing production of the metallurgical and mining industries and the lack of an acceptable method for disposing of the waste created by these industries. On the other hand, it may be explained by the increasing stringency of environmental laws in the majority of the world's wealthy countries. Lead and mercury, radioactive elements, and other mining tails-related contaminants are actively released into the environment as a result of the construction of tails, biota, polluting soils, air, and water and causing human cancer. Pollutants from food production and animal waste devastate farmland and natural areas. The use of tailing dams increases the likelihood of man-made catastrophes [3, 4]. ‎

In addition, mine tailings should be seen as a mineral supply that has been extracted from the subsurface of the earth, transported, and misapplied from the standpoint of rational natural resource management. This perspective is supported, in part, by the fact that the tailings may include trace amounts of target material as well as previously unclaimed components that may be recovered using more effective mining procedures [5-10]. In contrast, the chemical composition of mine tailings consists predominantly of silicon, aluminum, and calcium oxides, in proportions ranging from 60 to 90 percent [1-4, 11, 12]. As a result, tailings have the potential to serve as an alternative source for a number of construction and industrial applications [12-14].

Using mine tailings as geopolymers and precursors of alkali-activated materials or aggregates [15-17] seems to be a promising trend in the use of mine tailings. Geopolymers are mostly composed of amorphous sodium aluminum silicate hydrate. The majority of the products of the reaction between aluminosilicate powder and alkaline solution are solids. [19]. According to van Deventer et al. [18], the geopolymer network is made of AlO4 and SiO4 tetrahedra joined by oxygen atoms [19]; positively charged ions (such as Ca2+, Na+, K+, and Li+) present in the cavity framework counteract the negative charge. It is possible that using mine tailings as a geopolymer will not only slow the accumulation of mine tailings and reduce the level of ecological contamination, but it will also combine the benefits of geopolymer technology associated with a reduction in carbon dioxide release into the environment, the possibility of utilizing other forms of aluminosilicate waste, and the versatility of geopolymer properties [20-24]. Diverse pros have lately acquired substantial new understanding about the management of tails in typical ways. Over a dozen studies have been published documenting the efforts made to increase our understanding of the geopolymerization processes of tails in order to manage the properties of geopolymers for applications such as pollution removal [25-32], sustainable building [28-32], and other specific uses [13-17].

The composition of the mine tailings in terms of minerals, aggregates, and chemicals is heterogeneous [11, 33-39]. Moreover, mine tailings include dangerous and toxic chemicals related to waste products or mining processes [40-44], although containing relatively small amounts of valuable components. All of these factors make it more challenging to directly manage mine tailings in order to produce geopolymers that comply with environmental safety rules for impurity content while also achieving the complex functional attributes required for the produced product [45, 46].

Consequently, overcoming the issues associated with the use of mine tailings-geopolymer composites is especially advantageous, both in terms of mitigating the negative environmental impact and the promise of extending the resource base of produced mineral raw materials. It is very beneficial to address the difficulties related with the use of mine tailings-geopolymer composites. This paper begins with a consideration of some of the physicochemical and environmental obstacles associated with the use of mine tailings-geopolymer composites. This study examines in detail the link between mine tailings-geopolymer composites' structural, mechanical, and thermal capacity, along with their durability and other key characteristics. In addition to the beneficial aspects of the development of the characteristics of mine tailings-geopolymer composites, we discuss in detail the well-known applications of their use.

2. Thermal properties

As previously stated, geopolymers, in contrast to OPC binders, are recognized for their high thermal stability and the ability to retain strength even after being subjected to high temperatures [77, 78]. This is because of the unique characteristics of its structure, which is formed by branched AlO₄ and SiO₄ tetrahedral frameworks [77, 78]. The type of aggregate used to make geopolymers also plays a key role in the advancement of their thermal properties. This is because geopolymers can be made with several types of aggregates, such as aluminum-silicate aggregates. It should be noted that, when geopolymers have tails, a careful study of how these materials change and how well they work like insulation and fire-resistant materials is needed to figure out if they can be used [79-84].

Ye, et al [85] investigated the impact of raised temperatures on the characteristics of a geopolymer made from bauxite tailings and slag. They discovered that the compressive strength of geopolymer is somewhat boosted after exposure to 200 ºC but that it rapidly reduces after exposure to 600 ºC. However, the drop in compressive strength was substantial between 600 and 1000 ºC, with a little gain in compressive strength at 1200 ºC. Anorthite (CaAl₂(SiO₄ )₂), a type of ceramic, was discovered to be associated with an increase in strength, which could be attributed to self-healing and densification caused by sintering. The noticed drop in compressive strength at temperatures reaching 800 ºC is because of the dissolution of the amorphous stage as well as an extra thermal mismatch between the contracting gels throughout the contracting process. There is also physical harm in the form of cracking on the surface of samples. This is also in line with the findings of the compression experiment, which showed that there is no severe cracking on the sample when it reaches 400 ºC. It gets more violent as the temperature rises, so it starts at 600 ºC and goes up to 1200 ºC. Also, the width of micro-pores in its geopolymer gets bigger as the temperature of the material gets higher.

According to Jiao, et al [86], the strength gain of mine tailings-geopolymer composites when subjected to high temperatures has also been reported. As a result of sintering, the geopolymers produced by the alkali-activated of vanadium tailings with high silica content demonstrated an improvement in compressive strength at temperatures above 900 ºC. This was accompanied by a lowering in the content of unreacted aluminosilicate precursor particles and the development of a denser microstructure by means of sintering, as shown in Fig. 2. As illustrated in Fig. 3, heating to 1000 ºC reduces bulk density and strength while increasing fracture and porosity. This effect was revealed to be caused by volume expansion and severe thermal incompatibility.

Fig. 2. SEM microanalysis of the geopolymer specimen: (a) ambient temperature; (b) at 900 ºC; and (c) at 1050 ºC [86].

Fig. 3. Compressive strength, residual mass, and bulk density of the geopolymer specimen at high temperatures [86].

3. Leaching behavior

The presence of various heavy metals in mine tailings is a major environmental concern. To prevent their spread in soils and groundwater due to leaching, solidification (stabilization) through geopolymerization can be considered as one of the sustainable methods for neutralizing tailings containing toxic elements. In this regard, leaching characteristics are important indicators describing the effectiveness of heavy metal immobilization in geopolymers. As a result, making mine tailings-based geopolymers requires extra care when choosing the best ways and parts to make them [87-92].

The ability to successfully immobilize the heavy metals contained in lead-zinc tailings via physical and chemical ways was demonstrated by Zhao, et al [93] in geopolymer based on coal gangue and blast furnace slag. Although an increase in tailings in prepared samples led to an increase in the concentration of Zn²⁺, Pb²⁺, and Cd²⁺ in the leaching solution, these values remained within acceptable limits [93]. The obtained geopolymer samples were characterized by a compact structure, wherein the crystalline phase Zn²⁺ was found; the amorphous phases were characterized by the content of Pb²⁺ and Cd²⁺.

Heavy metal cations can form chemical bonds with reactive components during polycondensation, which can lead to the formation of new phases. The formation of the PbO/BaSiO3 phase was observed by Hu, et al [94] in rare earth tailing-based geopolymers. This is because Pb2⁺ and Ba2⁺ interact with unbridged oxygen or the Si/Al chain, which makes sure that the heavy metals stay in place inside the framework.

Ahmari and Zhang [49] reported no effective immobilization of arsenic and molybdenum due to geopolymerization in copper mine tailings-based geopolymers [48]. The authors also suggested a methodology to predict trace elements in geopolymers (Fig. 4). The experimental leaching data in their investigation correlates well with the proposed paradigm. Many studies have examined the efficiency of gold mine tailings-based geopolymers in immobilizing heavy metals [50, 95]. It is observed that the immobilization efficiency of Cr, Cu, Zn, Ni, and Mn in gold mine tailings, metakaolin, and slag blended geopolymer is higher than 98% with the only exception of arsenic and vanadium (Va), whose leaching is higher in that geopolymer [95].

In gold mine tailings-based geopolymers, the immobilization efficiency of heavy metals is higher in PA and KOH activated gold mine tailings geopolymers than in those synthesized by PS and KOH [50]. Kiventerä, et al [96], Kiventerä, et al [97] also reported effective immobilization of sulfate and arsenic in gold mine tailings-based geopolymer using calcium hydroxide and slag. After 7 days of curing, their geopolymer contains over 90% sulfate and over 95% arsenic, with other heavy elements immobilized as well. Wan, et al [98], Wan, et al [99]reported that lead (Pb) can be effectively immobilized in the mine tailings-geopolymer. They found that the formation of geopolymer gel in the binders is very important to the immobilization of Pb.

Fig. 4. Measured and predicted concentrations of heavy metals at pH = 4 a by first-order reaction/diffusion model (FRDM) [48].

4. Conclusions

The key annotations for this paper review are as follows:

1. The minerals that form mine tailings are identified by their varying chemical reactivity to The interactions of the precursors' metal components in alkaline conditions affect the structure and characteristics of the geopolymer's aluminosilicate framework. Many times, the alkaline reactivity of mine tailings is extremely low, which is the best thing when mine tailings are used to make geopolymers.
2. No classification strategy for mine tailings is in place that is based on its Recent research findings, like employing the topological technique to assess glass interaction, can be utilized to categorize and classify these materials, hence encouraging their usage in geopolymerization applications.

5. Recommendations

The following are the main recommendations for future investigations:

1. The high silica concentration of mine tailings raises the molar proportion of SiO₂ /Al₂O₃ in mine tailings-geopolymer composites, impairing the process of A solution to this difficulty can be found by including additional precursors, like metakaolin or scattered aluminum oxide, into the mix. A preliminary classification of tailings-based on the characteristics of their mineralogical and chemical compositions is recommended.
2. Because of the low interaction of native metal trichlorides, the presence of beneficial components ingrained in the minerals initially processed, and the risk of toxic contamination by leaching components, utilizing tailings for geopolymer preparation is prohibitively expensive and time-consuming from an economic and production Aspects like the geographic closeness of the mining and processing enterprises to the mine tailings customers as well as the regions where finished geopolymer products are consumed should be taken into consideration when conducting a feasibility study for its application in geopolymer composites.
3. Pre-treatment of mine tailings can be utilized to boost their Therefore, further investigation is recommended in this regard.

References

[1] S. Qaidi, "Behaviour of Concrete Made of Recycled Waste PET and Confined with CFRP Fabrics," M.Sc., University of Duhok, Duhok, 2021.

[2] J. Ahmad et al., "A Comprehensive Review on the Ground Granulated Blast Furnace Slag (GGBS) in Concrete Production," Sustainability, vol. 14, no. 14, p. 8783, 2022 [Online]. Available: https://www.mdpi.com/2071-1050/14/14/8783.

[3] H. U. Ahmed, A. S. Mohammed, S. M. Qaidi, R. H. Faraj, N. Hamah Sor, and A. A. Mohammed, "Compressive strength of geopolymer concrete composites: a systematic comprehensive review, analysis and modeling," European Journal of Environmental and Civil Engineering, pp. 1-46, 2022.

[4] H. U. Ahmed, A. S. Mohammed, R. H. Faraj, S. M. Qaidi, and A. A. Mohammed, "Compressive strength of geopolymer concrete modified with nano-silica: Experimental and modeling investigations," Case Studies in Construction Materials, vol. 16, p. e01036, 2022.

[5] M. Rico, G. Benito, A. Salgueiro, A. Díez-Herrero, and H. Pereira, "Reported tailings dam failures: a review of the European incidents in the worldwide context," Journal of hazardous materials, vol. 152, no. 2, pp. 846-852, 2008.

[6] C. Zhang, X. Wang, Z. Hu, Q. Wu, H. Zhu, and J. Lu, "Long-term performance of silane coupling agent/metakaolin based geopolymer," Journal of Building Engineering, vol. 36, p. 102091, 2021/04/01/ 2021, doi: https://doi.org/10.1016/j.jobe.2020.102091.

[7] C. Rodrigue Kaze et al., "Synergetic effect of rice husk ash and quartz sand on microstructural and physical properties of laterite clay based geopolymer," Journal of Building Engineering, vol. 43, p. 103229, 2021/11/01/ 2021, doi: https://doi.org/10.1016/j.jobe.2021.103229.

[8] K. M. Klima, K. Schollbach, H. J. H. Brouwers, and Q. Yu, "Enhancing the thermal performance of Class F fly ash-based geopolymer by sodalite," Construction and Building Materials, vol. 314, p. 125574, 2022/01/03/ 2022, doi: https://doi.org/10.1016/j.conbuildmat.2021.125574.

[9] K. V. S. Gopala Krishna Sastry, P. Sahitya, and A. Ravitheja, "Influence of nano TiO2 on strength and durability properties of geopolymer concrete," Materials Today: Proceedings, vol. 45, pp. 1017-1025, 2021/01/01/ 2021, doi: https://doi.org/10.1016/j.matpr.2020.03.139.

[10] M. Catauro, F. Barrino, S. Pacifico, S. Piccolella, I. Lancellotti, and C. Leonelli, "Synthesis of WEEE-based geopolymers and their cytotoxicity," Materials Today: Proceedings, vol. 34, pp. 121-124, 2021/01/01/ 2021, doi: https://doi.org/10.1016/j.matpr.2020.01.408.

[11] G. Lazorenko, A. Kasprzhitskii, F. Shaikh, R. Krishna, and J. Mishra, "Utilization potential of mine tailings in geopolymers: Part 1. Physicochemical and environmental aspects," Process Safety and Environmental Protection, 2021.

[12] H. U. Ahmed et al., "Compressive Strength of Sustainable Geopolymer Concrete Composites: A State-of-the-Art Review," Sustainability, vol. 13, no. 24, p. 13502, 2021 [Online]. Available: https://www.mdpi.com/2071-1050/13/24/13502.

[13] F. A. Jawad Ahmad, Rebeca Martinez‑Garcia, Jesús de‑Prado‑Gil, Shaker M. A. Qaidi, Ameni Brahmia, "Effects of waste glass and waste marble on mechanical and durability performance of concrete," Scientific Reports, vol. 11, no. 1, p. 21525, 2021.

[14] F. Aslam et al., "Evaluating the influence of fly ash and waste glass on the characteristics of coconut fibers reinforced concrete," Structural Concrete, vol. n/a, no. n/a, doi: https://doi.org/10.1002/suco.202200183.

[15] M. M. Al-Tayeb, Y. I. A. Aisheh, S. M. A. Qaidi, and B. A. Tayeh, "Experimental and simulation study on the impact resistance of concrete to replace high amounts of fine aggregate with plastic waste," Case Studies in Construction Materials, p. e01324, 2022/07/19/ 2022, doi: https://doi.org/10.1016/j.cscm.2022.e01324.

[16] H. Unis Ahmed et al., "Geopolymer concrete as a cleaner construction material: An overview on materials and structural performances," Cleaner Materials, vol. 5, p. 100111, 2022/09/01/ 2022, doi: https://doi.org/10.1016/j.clema.2022.100111.

[17] A. Mansi, N. H. Sor, N. Hilal, and S. M. Qaidi, "The impact of nano clay on normal and high-performance concrete characteristics: a review," in IOP Conference Series: Earth and Environmental Science, 2022, vol. 961, no. 1: IOP Publishing, p. 012085.

[18] J. S. van Deventer, J. L. Provis, P. Duxson, and D. G. Brice, "Chemical research and climate change as drivers in the commercial adoption of alkali activated materials," Waste and Biomass Valorization, vol. 1, no. 1, pp. 145-155, 2010.

[19] J. L. Provis and J. S. J. Van Deventer, Geopolymers: structures, processing, properties and industrial applications. Elsevier, 2009.

[20] G. Lazorenko et al., "Effect of pre-treatment of flax tows on mechanical properties and microstructure of natural fiber reinforced geopolymer composites," Environmental Technology & Innovation, vol. 20, p. 101105, 2020.

[21] G. Lazorenko, A. Kasprzhitskii, A. Kruglikov, V. Mischinenko, and V. Yavna, "Sustainable geopolymer composites reinforced with flax tows," Ceramics International, vol. 46, no. 8, pp. 12870-12875, 2020.

[22] A. Hassan, M. Arif, and M. Shariq, "Use of geopolymer concrete for a cleaner and sustainable environment–A review of mechanical properties and microstructure," Journal of cleaner production, vol. 223, pp. 704-728, 2019.

[23] M. Chau-Khun, A. A. Zawawi, and O. Wahid, "Structural and material performance of geopolymer concrete 2018," ed: ELSEVIER, 2018.

[24] S. T, K. R. P.R, S. M, S. A, and J. R, "A state-of-the-art on development of geopolymer concrete and its field applications," Case Studies in Construction Materials, vol. 16, p. e00812, 2022/06/01/ 2022, doi: https://doi.org/10.1016/j.cscm.2021.e00812.

[25] F. Demir and E. Moroydor Derun, "Usage of gold mine tailings based geopolymer on Cu 2+ adsorption from water," Main Group Chemistry, vol. 18, no. 4, pp. 467-476, 2019.

[26] F. Demir and E. M. Derun, "Modelling and optimization of gold mine tailings based geopolymer by using response surface method and its application in Pb2+ removal," Journal of Cleaner Production, vol. 237, p. 117766, 2019.

[27] A. A. Siyal et al., "A review on geopolymers as emerging materials for the adsorption of heavy metals and dyes," Journal of Environmental Management, vol. 224, pp. 327-339, 2018/10/15/ 2018, doi: https://doi.org/10.1016/j.jenvman.2018.07.046.

[28] S. Moukannaa, A. Nazari, A. Bagheri, M. Loutou, J. Sanjayan, and R. Hakkou, "Alkaline fused phosphate mine tailings for geopolymer mortar synthesis: Thermal stability, mechanical and microstructural properties," Journal of Non-Crystalline Solids, vol. 511, pp. 76-85, 2019.

[29] N. Zhang, A. Hedayat, H. G. Bolaños Sosa, N. Tupa, I. Yanqui Morales, and R. S. Canahua Loza, "Crack evolution in the Brazilian disks of the mine tailings-based geopolymers measured from digital image correlations: An experimental investigation considering the effects of class F fly ash additions," Ceramics International, vol. 47, no. 22, pp. 32382-32396, 2021/11/15/ 2021, doi: https://doi.org/10.1016/j.ceramint.2021.08.138.

[30] N. Zhang et al., "On the incorporation of class F fly-ash to enhance the geopolymerization effects and splitting tensile strength of the gold mine tailings-based geopolymer," Construction and Building Materials, vol. 308, p. 125112, 2021/11/15/ 2021, doi: https://doi.org/10.1016/j.conbuildmat.2021.125112.

[31] N. Zhang, A. Hedayat, H. G. Bolaños Sosa, J. J. González Cárdenas, G. E. Salas Álvarez, and V. B. Ascuña Rivera, "Specimen size effects on the mechanical behaviors and failure patterns of the mine tailings-based geopolymer under uniaxial compression," Construction and Building Materials, vol. 281, p. 122525, 2021/04/26/ 2021, doi: https://doi.org/10.1016/j.conbuildmat.2021.122525.

[32] A. R. de Azevedo et al., "Circular economy and durability in geopolymers ceramics pieces obtained from glass polishing waste," International Journal of Applied Ceramic Technology, 2021.

[33] S. M. A. Qaidi, "Ultra-high-performance fiber-reinforced concrete: Mixture design," University of Duhok, Duhok, 2022.

[34] S. M. A. Qaidi, "Ultra-high-performance fiber-reinforced concrete: Principles and raw materials," University of Duhok, Duhok, 2022.

[35] M. H. Akeed et al., "Ultra-high-performance fiber-reinforced concrete. Part I: Developments, principles, raw materials," Case Studies in Construction Materials, vol. 17, p. e01290, 2022/12/01/ 2022, doi: https://doi.org/10.1016/j.cscm.2022.e01290.

[36] M. H. Akeed et al., "Ultra-high-performance fiber-reinforced concrete. Part II: Hydration and microstructure," Case Studies in Construction Materials, vol. 17, p. e01289, 2022/12/01/ 2022, doi: https://doi.org/10.1016/j.cscm.2022.e01289.

[37] M. H. Akeed et al., "Ultra-high-performance fiber-reinforced concrete. Part III: Fresh and hardened properties," Case Studies in Construction Materials, vol. 17, p. e01265, 2022/12/01/ 2022, doi: https://doi.org/10.1016/j.cscm.2022.e01265.

[38] M. H. Akeed et al., "Ultra-high-performance fiber-reinforced concrete. Part IV: Durability properties, cost assessment, applications, and challenges," Case Studies in Construction Materials, vol. 17, p. e01271, 2022/12/01/ 2022, doi: https://doi.org/10.1016/j.cscm.2022.e01271.

[39] S. M. A. Qaidi et al., "Ultra-high-performance geopolymer concrete: A review," Construction and Building Materials, vol. 346, p. 128495, 2022/09/05/ 2022, doi: https://doi.org/10.1016/j.conbuildmat.2022.128495.

[40] C. Anning, J. Wang, P. Chen, I. Batmunkh, and X. Lyu, "Determination and detoxification of cyanide in gold mine tailings: A review," Waste Management & Research, vol. 37, no. 11, pp. 1117-1126, 2019.

[41] I. Park et al., "A review of recent strategies for acid mine drainage prevention and mine tailings recycling," Chemosphere, vol. 219, pp. 588-606, 2019.

[42] E. M. Opiso, C. B. Tabelin, C. V. Maestre, J. P. J. Aseniero, I. Park, and M. Villacorte-Tabelin, "Synthesis and characterization of coal fly ash and palm oil fuel ash modified artisanal and small-scale gold mine (ASGM) tailings based geopolymer using sugar mill lime sludge as Ca-based activator," Heliyon, vol. 7, no. 4, p. e06654, 2021/04/01/ 2021, doi: https://doi.org/10.1016/j.heliyon.2021.e06654.

[43] G. Lazorenko, A. Kasprzhitskii, F. Shaikh, R. S. Krishna, and J. Mishra, "Utilization potential of mine tailings in geopolymers: Physicochemical and environmental aspects," Process Safety and Environmental Protection, vol. 147, pp. 559-577, 2021/03/01/ 2021, doi: https://doi.org/10.1016/j.psep.2020.12.028.

[44] E. Arioz, O. Arioz, and O. M. Kockar, "Leaching of F-type fly Ash Based Geopolymers," Procedia Engineering, vol. 42, pp. 1114-1120, 2012/01/01/ 2012, doi: https://doi.org/10.1016/j.proeng.2012.07.503.

[45] S. Qaidi, "Ultra-high-performance geopolymer concrete. Part 1: Manufacture approaches," University of Duhok, Duhok, 41, 2022 [Online]. Available: https://scholar.google.com/citations?view_op=view_citation&hl=en&user=V5wA2xMAAAAJ&pagesize=80&sortby=title&citation_for_view=V5wA2xMAAAAJ:maZDTaKrznsC

[46] S. Qaidi, "Ultra-high-performance geopolymer concrete. Part 2: Applications," University of Duhok, Duhok, 42, 2022 [Online]. Available: https://scholar.google.com/citations?view_op=view_citation&hl=en&user=V5wA2xMAAAAJ&pagesize=80&sortby=title&citation_for_view=V5wA2xMAAAAJ:M3NEmzRMIkIC

[47] E. Caballero, W. Sánchez, and C. A. Ríos, "Synthesis of geopolymers from alkaline activation of gold mining wastes," Ingeniería y competitividad, vol. 16, no. 1, pp. 317-330, 2014.

[48] S. Ahmari and L. Zhang, "Durability and leaching behavior of mine tailings-based geopolymer bricks," Construction and building materials, vol. 44, pp. 743-750, 2013.

[49] S. Ahmari and L. Zhang, "Utilization of cement kiln dust (CKD) to enhance mine tailings-based geopolymer bricks," Construction and Building Materials, vol. 40, pp. 1002-1011, 2013.

[50] T. Falayi, "Effect of potassium silicate and aluminate on the stabilisation of gold mine tailings," in Proceedings of the Institution of Civil Engineers-Waste and Resource Management, 2019, vol. 172, no. 2: Thomas Telford Ltd, pp. 56-63.

[51] Y. I. A. Aisheh, D. S. Atrushi, M. H. Akeed, S. Qaidi, and B. A. Tayeh, "Influence of polypropylene and steel fibers on the mechanical properties of ultra-high-performance fiber-reinforced geopolymer concrete," Case Studies in Construction Materials, vol. 17, p. e01234, 2022.

[52] Y. I. A. Aisheh, D. S. Atrushi, M. H. Akeed, S. Qaidi, and B. A. Tayeh, "Influence of steel fibers and microsilica on the mechanical properties of ultra-high-performance geopolymer concrete (UHP-GPC)," Case Studies in Construction Materials, vol. 17, p. e01245, 2022/12/01/ 2022, doi: https://doi.org/10.1016/j.cscm.2022.e01245.

[53] I. Almeshal, M. M. Al-Tayeb, S. M. A. Qaidi, B. H. Abu Bakar, and B. A. Tayeh, "Mechanical properties of eco-friendly cements-based glass powder in aggressive medium," Materials Today: Proceedings, vol. 58, pp. 1582-1587, 2022/01/01/ 2022, doi: https://doi.org/10.1016/j.matpr.2022.03.613.

[54] X. He et al., "Mine tailings-based geopolymers: A comprehensive review," Ceramics International, vol. 48, no. 17, pp. 24192-24212, 2022/09/01/ 2022, doi: https://doi.org/10.1016/j.ceramint.2022.05.345.

[55] R. H. Faraj, H. U. Ahmed, S. Rafiq, N. H. Sor, D. F. Ibrahim, and S. M. A. Qaidi, "Performance of Self-Compacting Mortars Modified with Nanoparticles: A Systematic Review and Modeling," Cleaner Materials, no. 2772-3976, p. 100086, 2022.

[56] S. M. A. Qaidi, "PET-Concrete," University of Duhok, Duhok, 2021.

[57] P. H. Ribeiro Borges, F. C. Resende Ramos, T. Rodrigues Caetano, T. Hallak Panzerra, and H. Santos, "Reuse of iron ore tailings in the production of geopolymer mortars," Rem: Revista Escola de Minas, vol. 72, no. 4, 2019.

[58] S. Qaidi, "Ultra-high-performance geopolymer concrete. Part 3: Environmental parameters," University of Duhok, Duhok, 43, 2022 [Online]. Available: https://scholar.google.com/citations?view_op=view_citation&hl=en&user=V5wA2xMAAAAJ&pagesize=80&sortby=title&citation_for_view=V5wA2xMAAAAJ:JV2RwH3_ST0C

[59] S. Qaidi, "Ultra-high-performance geopolymer concrete. Part 4: Mix design methods ‎," University of Duhok, Duhok, 44, 2022 [Online]. Available: https://scholar.google.com/citations?view_op=view_citation&hl=en&user=V5wA2xMAAAAJ&pagesize=80&sortby=title&citation_for_view=V5wA2xMAAAAJ:blknAaTinKkC

[60] S. Qaidi, "Ultra-high-performance geopolymer concrete. Part 5: Fresh properties," University of Duhok, Duhok, 45, 2022 [Online]. Available: https://scholar.google.com/citations?view_op=view_citation&hl=en&user=V5wA2xMAAAAJ&pagesize=80&sortby=title&citation_for_view=V5wA2xMAAAAJ:hMod-77fHWUC

[61] M. Falah, R. Obenaus-Emler, P. Kinnunen, and M. Illikainen, "Effects of activator properties and curing conditions on alkali-activation of low-alumina mine tailings," Waste and Biomass Valorization, pp. 1-13, 2019.

[62] L. Manjarrez, A. Nikvar-Hassani, R. Shadnia, and L. Zhang, "Experimental study of geopolymer binder synthesized with copper mine tailings and low-calcium copper slag," Journal of Materials in Civil Engineering, vol. 31, no. 8, p. 04019156, 2019.

[63] S. M. A. Qaidi, "PET-concrete confinement with CFRP," University of Duhok, Duhok, 2021.

[64] S. M. Qaidi, B. A. Tayeh, A. M. Zeyad, A. R. de Azevedo, H. U. Ahmed, and W. Emad, "Recycling of mine tailings for the geopolymers production: A systematic review," Case Studies in Construction Materials, p. e00933, 2022.

[65] S. M. A. Qaidi et al., "Rubberized geopolymer composites: A comprehensive review," Ceramics International, vol. 48, no. 17, pp. 24234-24259, 2022/09/01/ 2022, doi: https://doi.org/10.1016/j.ceramint.2022.06.123.

[66] A. M. Jawad Ahmad, Ahmed Babeker Elhag, Ahmed Farouk Deifalla, Mahfooz Soomro, Haytham F. Isleem, Shaker Qaidi, "A Step towards Sustainable Concrete with Substitution of Plastic Waste in Concrete: Overview on Mechanical, Durability and Microstructure Analysis," Crystals, vol. 12, no. 7, p. 944, 2022.

[67] A. M. Maglad et al., "A Study on the Properties of Geopolymer Concrete Modified with Nano Graphene Oxide," Buildings, vol. 12, no. 8, p. 1066, 2022 [Online]. Available: https://www.mdpi.com/2075-5309/12/8/1066.

[68] X. Ren, L. Zhang, D. Ramey, B. Waterman, and S. Ormsby, "Utilization of aluminum sludge (AS) to enhance mine tailings-based geopolymer," Journal of materials science, vol. 50, no. 3, pp. 1370-1381, 2015.

[69] S. Qaidi, "Ultra-high-performance geopolymer concrete. Part 6: Mechanical properties," University of Duhok, Duhok, 46, 2022 [Online]. Available: https://scholar.google.com/citations?view_op=view_citation&hl=en&user=V5wA2xMAAAAJ&pagesize=80&sortby=title&citation_for_view=V5wA2xMAAAAJ:NMxIlDl6LWMC

[70] S. Qaidi, "Ultra-high-performance geopolymer concrete. Part 7: Mechanical performance correlation," University of Duhok, Duhok, 47, 2022 [Online]. Available: https://scholar.google.com/citations?view_op=view_citation&hl=en&user=V5wA2xMAAAAJ&pagesize=80&sortby=title&citation_for_view=V5wA2xMAAAAJ:YFjsv_pBGBYC

[71] S. Qaidi, "Ultra-high-performance geopolymer concrete. Part 8: Dynamic behavior," University of Duhok, Duhok, 48, 2022 [Online]. Available: https://scholar.google.com/citations?view_op=view_citation&hl=en&user=V5wA2xMAAAAJ&pagesize=80&sortby=title&citation_for_view=V5wA2xMAAAAJ:BqipwSGYUEgC

[72] S. Qaidi, "Ultra-high-performance geopolymer concrete. Part 9: Strain hardening," University of Duhok, Duhok, 49, 2022 [Online]. Available: https://scholar.google.com/citations?view_op=view_citation&hl=en&user=V5wA2xMAAAAJ&pagesize=80&sortby=title&citation_for_view=V5wA2xMAAAAJ:GnPB-g6toBAC

[73] S. Qaidi, "Ultra-high-performance geopolymer concrete. Part 10: Durability properties," University of Duhok, Duhok, 50, 2022.

[74] S. Qaidi, "Ultra-high-performance geopolymer concrete. Part 11: Microstructural properties," University of Duhok, Duhok, 51, 2022 [Online]. Available: https://scholar.google.com/citations?view_op=view_citation&hl=en&user=V5wA2xMAAAAJ&cstart=20&pagesize=80&sortby=title&citation_for_view=V5wA2xMAAAAJ:M3NEmzRMIkIC

[75] P. Duan, C. Yan, W. Zhou, and D. Ren, "Development of fly ash and iron ore tailing based porous geopolymer for removal of Cu (II) from wastewater," Ceramics International, vol. 42, no. 12, pp. 13507-13518, 2016.

[76] P. Duan, C. Yan, W. Zhou, and D. Ren, "Fresh properties, compressive strength and microstructure of fly ash geopolymer paste blended with iron ore tailing under thermal cycle," Construction and Building Materials, vol. 118, pp. 76-88, 2016.

[77] G. Liang, H. Zhu, Z. Zhang, and Q. Wu, "Effect of rice husk ash addition on the compressive strength and thermal stability of metakaolin based geopolymer," Construction and Building Materials, vol. 222, pp. 872-881, 2019.

[78] H. Y. Zhang, G. H. Qiu, V. Kodur, and Z. S. Yuan, "Spalling behavior of metakaolin-fly ash based geopolymer concrete under elevated temperature exposure," Cement and Concrete Composites, vol. 106, p. 103483, 2020.

[79] S. M. A. Qaidi, B. A. Tayeh, H. F. Isleem, A. R. G. de Azevedo, H. U. Ahmed, and W. Emad, "Sustainable utilization of red mud waste (bauxite residue) and slag for the production of geopolymer composites: A review," Case Studies in Construction Materials, vol. 16, p. e00994, 2022/06/01/ 2022, doi: https://doi.org/10.1016/j.cscm.2022.e00994.

[80] S. N. Ahmed, N. H. Sor, M. A. Ahmed, and S. M. A. Qaidi, "Thermal conductivity and hardened behavior of eco-friendly concrete incorporating waste polypropylene as fine aggregate," Materials Today: Proceedings, 2022.

[81] S. Qaidi, "Ultra-high-performance fiber-reinforced concrete (UHPFRC): A mini-review of the challenges," ScienceOpen Preprints, doi: 10.14293/S2199-1006.1.SOR-.PPA6YEF.v1.

[82] S. Qaidi, "Ultra-High-Performance Fiber-Reinforced Concrete: Applications," Preprints, 2022, doi: http://dx.doi.org/10.20944/preprints202207.0271.v1.

[83] S. M. A. Qaidi, "Ultra-high-performance fiber-reinforced concrete: Applications," University of Duhok, Duhok, 2022.

[84] S. M. A. Qaidi, "Ultra-high-performance fiber-reinforced concrete: Challenges," University of Duhok, Duhok, 2022.

[85] J. Ye, W. Zhang, and D. Shi, "Effect of elevated temperature on the properties of geopolymer synthesized from calcined ore-dressing tailing of bauxite and ground-granulated blast furnace slag," Construction and Building Materials, vol. 69, pp. 41-48, 2014.

[86] X. Jiao, Y. Zhang, and T. Chen, "Thermal stability of a silica-rich vanadium tailing based geopolymer," Construction and Building Materials, vol. 38, pp. 43-47, 2013.

[87] S. M. A. Qaidi, "Ultra-high-performance fiber-reinforced concrete: Cost assessment," University of Duhok, Duhok, 2022.

[88] S. M. A. Qaidi, "Ultra-high-performance fiber-reinforced concrete: Durability properties," University of Duhok, Duhok, 2022.

[89] S. Qaidi, "Ultra-High-Performance Fiber-Reinforced Concrete: Fresh Properties," Preprints, 2022, doi: http://dx.doi.org/10.20944/preprints202207.0406.v1.

[90] S. M. A. Qaidi, "Ultra-high-performance fiber-reinforced concrete: Fresh properties," University of Duhok, Duhok, 2022.

[91] S. M. A. Qaidi, "Ultra-high-performance fiber-reinforced concrete: Hardened properties," University of Duhok (UoD), 2022.

[92] S. M. A. Qaidi, "Ultra-high-performance fiber-reinforced concrete: Hydration and microstructure," University of Duhok, Duhok, 2022.

[93] S. Zhao, M. Xia, L. Yu, X. Huang, B. Jiao, and D. Li, "Optimization for the preparation of composite geopolymer using response surface methodology and its application in lead-zinc tailings solidification," Construction and Building Materials, vol. 266, p. 120969, 2021.

[94] S. Hu et al., "Synthesis of rare earth tailing-based geopolymer for efficiently immobilizing heavy metals," Construction and Building Materials, vol. 254, p. 119273, 2020.

[95] J. Kiventerä, J. Yliniemi, L. Golek, J. Deja, V. Ferreira, and M. Illikainen, "Utilization of sulphidic mine tailings in alkali-activated materials," in MATEC Web of Conferences, 2019, vol. 274: EDP Sciences, p. 01001.

[96] J. Kiventerä, H. Sreenivasan, C. Cheeseman, P. Kinnunen, and M. Illikainen, "Immobilization of sulfates and heavy metals in gold mine tailings by sodium silicate and hydrated lime," Journal of environmental chemical engineering, vol. 6, no. 5, pp. 6530-6536, 2018.

[97] J. Kiventerä, I. Lancellotti, M. Catauro, F. Dal Poggetto, C. Leonelli, and M. Illikainen, "Alkali activation as new option for gold mine tailings inertization," Journal of cleaner production, vol. 187, pp. 76-84, 2018.

[98] Q. Wan, F. Rao, S. Song, and Y. Zhang, "Immobilization forms of ZnO in the solidification/stabilization (S/S) of a zinc mine tailing through geopolymerization," Journal of materials research and technology, vol. 8, no. 6, pp. 5728-5735, 2019.

[99] Q. Wan, F. Rao, S. Song, C. A. Leon‐Patino, Y. Ma, and W. Yin, "Consolidation of mine tailings through geopolymerization at ambient temperature," Journal of the American ceramic society, vol. 102, no. 5, pp. 2451-2461, 2019.