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Article

Exploring Raw Red Clay as a Supplementary Cementitious Material: Composition, Thermo-Mechanical Performance, Cost, and Environmental Impact

by
Mohammed Drissi
1,*,
Othmane Horma
1,
Ahmed Mezrhab
1 and
Mustapha Karkri
2
1
Mechanics and Energy Laboratory, Mohammed First University, Oujda 60000, Morocco
2
CERTES, Université Paris-Est Créteil, F-94010 Créteil, France
*
Author to whom correspondence should be addressed.
Buildings 2024, 14(12), 3906; https://doi.org/10.3390/buildings14123906
Submission received: 14 October 2024 / Revised: 11 November 2024 / Accepted: 4 December 2024 / Published: 6 December 2024
(This article belongs to the Special Issue Development and Properties of Sustainable Composite Materials for Building Applications)
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Abstract

:
This study explored the potential of natural red clay as a supplementary cementitious material (SCM) to reduce greenhouse gas emissions and costs associated with the cement industry. Given that cement production is one of the largest contributors to global greenhouse gas emissions, developing sustainable alternatives is of paramount importance. Recognizing the environmental impact of cement production, this research investigates the substitution of conventional cement with raw red clay, aiming to balance mechanical performance with enhanced thermal properties and a lower environmental footprint. Through chemical characterization using X-ray Fluorescence (XRF), along with comprehensive mechanical and thermal performance testing, this study identifies the dual role of raw clay in mortar. It was found that incorporating up to 5% by weight of raw clay slightly impacted compressive strength while significantly improving thermal conductivity and diffusivity, cost-efficiency, and environmental sustainability, making it an appealing option for structural applications requiring high mechanical resistance. Conversely, a higher proportion of clay (beyond 5%) compromises compressive strength, but further enhances thermal properties and environmental benefits, suggesting its suitability for applications where low mechanical resistance is acceptable. This investigation highlights the viability of raw clay as a promising SCM, offering a pathway to more sustainable construction materials without the need for energy-intensive processing, thereby contributing to the reduction in the construction sector’s carbon footprint and energy demand.

1. Introduction

The cement industry is among the primary contributors to greenhouse gas emissions, accounting for an estimated 7% of the total carbon dioxide emitted annually. Additionally, producing one ton of cement requires approximately 5.6 GWh of energy [1,2]. To address these environmental and energy challenges, it is essential to explore ecological and cost-effective cementitious materials that can partially replace conventional cement. Supplementary cementitious materials (SCMs) are often used to reduce the amount of cement in concrete/mortar mixtures [3]. According to ASTM C125, a pozzolan is a siliceous or siliceous–aluminous material that, on its own, has little or no cementitious value. However, when finely divided and in the presence of moisture, it chemically reacts with calcium hydroxide at normal temperatures to form compounds exhibiting cementitious properties [4].
The most commonly used SCMs include fly ash from coal-fired power plants, granulated blast furnace slag, and limestone [5]. However, these materials alone cannot fully meet the extensive demand for cement replacements. Although fly ash production is relatively high (approximately 30% of cement production), only a limited percentage can be effectively used due to its low reactivity. Furthermore, as coal and lignite power plants are progressively decommissioned, the availability of fly ash is expected to decrease significantly. Similarly, global slag production is limited to about 5–10% of cement production, which falls short of potential demand. Lastly, while limestone is readily available, its use above 10% in cement formulations can lead to increased porosity and compromised mechanical properties. [4,6].
Among the considered materials, clay is currently widely utilized as an SCM to enhance the performance of cement mortars [7], and numerous studies have been conducted to assess its characteristics. Red clay is a type of soil characterized by its red color, resulting from chemical weathering and the presence of clayey silt [8]. It forms under the influence of specific geological, climatic, and geographic conditions, resulting in a long-term clayey mud created through alteration and lateritization processes [9]. Red clay soil is notable for its abundant mineral resources, and is prevalent in semi-arid regions across North Africa, China, Northern and Central Asia, Russia, Southern and Central Europe, and North America, covering approximately 10% of the Earth’s land surface [10]. Extensive research on the utilization of red clay as a building material has highlighted its potential as a pozzolanic material.
Red clays are characterized by their abundance in silicate minerals, including montmorillonite, kaolinite, chlorite, and illite, which exhibit strong hydrophilic and rheological properties [9,11]. Their calcination results in the formation of amorphous silica, showcasing heightened reactivity with cement [12]. Calcined clay has been studied extensively, and considerable knowledge has been collected about its characteristics. Kaolinitic clay typically exhibits superior pozzolanic reactivity, reacting swiftly and pronouncedly with calcium derived from Portland clinker [6]. Conversely, illitic clays and montmorillonite, which require elevated activation temperatures and display slower pozzolanic activity, are the most abundant clay types in various regions worldwide [11].
Several studies have focused on the investigation of calcined clay [13]. He et al. [14] indicated that clay calcination at 930 °C for 100 min induced maximum activity and resulted in superior performance compared to reference cement. Additionally, numerous experimental studies have assessed the efficiency of calcined clay in combination with limestone (LC3 technology), with documented strengths that match or surpass those of conventional cement [15]. However, clay calcination has a significant environmental impact. Producing 1 kg of fired clay at 950–1200 °C generates up to 282 g of carbon dioxide, 5.78 g of carbon monoxide, 0.29 g of carbon black, and 1.56 g of particulate matter, in addition to 0.54–3.14 MJ/kg of energy consumption, depending on the efficiency of the kiln and type of fuel used [16].
Consequently, raw clay, which consists of various minerals without additional processing, has garnered attention for its potential environmental benefits. Minerals such as quartz, kaolinite, illite, silica, sepiolite, montmorillonite, and muscovite exhibit remarkable pozzolanic properties [17]. Raw clay has been utilized and extensively researched as a construction material throughout history [10]. For instance, B. Kim et al. [18], studied raw hwangtoh (red-yellow soil in Korean) to produce alkali-activated binder. Results showed that it can be used as a construction material, with a superior compressive strength of 21 MPa after four hours of curing in microwave at 61.4 °C using mixes composed of 9.50 g Na2O, 4.22 g SiO2, 41.28 g H2O, and 100 hwangtoh. K-H Yang et al. [19] investigated hwangtoh to develop a cementless mortar and eco-friendly building materials without carbon dioxide emissions. The results showed that the compressive strength of hwangtoh binder-based mortar was between 86% and 115% of that of the corresponding conventional cement mortar. M. N. Uddin et al. [20] conducted a comparative study between clay and red soil geopolymer, using calcium oxide as an alkaline activator; the results indicated that red soil exhibited 28% higher strength than clay.
Despite these findings, it has been shown that raw clay-containing mixes tend to impair workability, increase porosity, and diminish compressive strength [21,22]. M. Liu et al. [7] noted a decrease in flowability from 250 mm to approximately 220 mm upon the introduction of 10% bentonite clay. The diminished flowability of clay-based mixtures is primarily attributed to flocculation, wherein fine particles aggregate to form flocs, resulting in a fragile structure [17,23]. Flocculation involves the aggregation of coagulated colloids, leading to the formation of larger aggregates. Nwaubani et al. [21] attributed the observed strength reduction to raw clay’s propensity to aggregate cement particles and absorb substantial mixing water, thereby elevating water demand and impeding the hydration process. Therefore, it is necessary to conduct more studies to enhance mechanical performance while preserving red clay’s inherent characteristics [10].
However, beyond the mechanical performance degradation and the diminished flowability observed in concrete mixes, studies have shown that concrete incorporating raw clay exhibits enhanced resistance to sulfate and acid attacks compared to conventional cement, which is attributed to the formation of silica gel [24]. Moreover, the utilization of raw clay in its natural state eliminates the need for thermal treatment—a major source of pollutant gas emissions from cement production facilities—thus contributing to pollution reduction. This renders raw clay a valuable additive/filler that is particularly suitable for applications requiring low strength and improved thermal insulation, making it a promising resource to develop low-cost and environmentally friendly building materials.
The present study evaluated the performance of blended cements formulated using natural red clay in its raw state. The main goal of the investigation was to evaluate the thermomechanical performance of red clay as a partial substitute for cement to produce a low-cost and low-environmental-impact multicomponent blend. For this reason, the clay was characterized chemically and mineralogically using X-ray diffraction (XRD) and X-ray fluorescence (XRF). Subsequently, the produced mixes underwent vertical axial force testing to determine their compressive strength and were subjected to the heat flux generated by a heating sensor to determine their thermal conductivity and diffusivity.

2. Materials and Methods

2.1. Raw Materials and Mixes Proportion

The LafargeHolcim Portland composite cement (CM25) used in this study conformed to the Moroccan standard NM 10.1.004 [25]. Its constituents include clinker, limestone filler, and gypsum, with clinker comprising over 65%, and additives such as limestone or fly ash. This type of cement is primarily suited for the production of mortar and non-reinforced concrete (masonry, rendering, tiling) and other applications requiring lower strength. It exhibits a minimum strength that can develop up to over 22.5 MPa in 28 days.
Natural red clay sourced from the Mrija region in southern Jerada City, Morocco, with density of 768 kg/m3 constituted the second key material. The natural sand used, with a maximum particle size of 2.3 mm (Figure 1), was the predominant sand type in the region and was employed for mortar preparation. The main chemical elements of the raw clay were determined via X-ray fluorescence (XRF) analysis, as depicted in Table 1.
To evaluate the particle size distribution of the raw materials (cement, sand, and clay), a sedimentation test was performed according to the French standard NF P 49-057 [26]. This method determines particle size by measuring particles’ settling velocity in a viscous liquid. At specific time intervals, density measurements are taken to calculate the proportion of particles, which correspond to an equivalent mesh size based on mean particle diameters [27]. Figure 1 shows that the clay used has a particle size distribution similar to that of cement (<100 µm), enhancing its interaction with cement and acting as a pore-reducing agent in clay-based composites.
X-ray diffraction (XRD) analysis was conducted on ground raw clay to further understand its crystalline structure using a SHIMADZU XRD-6000 diffractometer (SHIMADZU CORPORATION, Tokyo, Japan). The analysis utilized Cu-Kα radiation with a wavelength (λ) of 0.154 nm and employed a scan rate of 2°/min over a 2θ-scale ranging from 0° to 80°. As shown in Figure 2, the XRD analysis revealed the predominant presence of Quartz and muscovite phases, along with traces of calcite present in raw red clay.
The elemental composition of the raw red clay was analyzed using a Shimadzu EDX-7000 Energy-Dispersive X-ray Fluorescence Spectrometer (XRF). This analysis provided insights into the major oxide and trace element composition of the raw materials. As seen in Table 1, the chemical composition shows that the clay is composed of more than 50% SiO2 with a significant presence of iron and aluminum oxide, which are essential for producing reactions with Portland cement.
Morphology and EDS spectra were assessed using Scanning Electron Microscopy (SEM, model SH-5500P, HIROX, Tokyo, Japan) equipped with an Energy-Dispersive Spectroscopy (EDS) unit (model BRUKER). The SEM micrographs, presented in Figure 3, reveal the irregular morphology characteristics of the clay’s fine particles. Additionally, the EDS spectra indicate a high concentration of silicon, aluminum, and iron on the clay’s surface, corroborating the compositional data obtained via X-ray Fluorescence (XRF) analysis shown in Table 1.
To comprehensively assess the effect of the incorporated clay on the thermal and mechanical properties, six clay-based formulations were developed with clay substitution ranging from 0 to 30% by weight in 5% increments, as outlined in Table 2. Before preparation, the clay was manually washed to remove impurities such as sand and organic matter, followed by sun drying for a week and subsequent grinding to achieve a particle size of ≤100 µm. To illustrate the effect of clay, the sand proportion and water-to-cement ratio were fixed at 1:3 (cement–sand) and 1:2 (water–cement), respectively, for all formulations, with cement progressively replaced by clay. During preparation, manual homogenization of cement and clay occurred for approximately 5 min before adding sand and water to the formulated binder (cement + clay), as illustrated in Figure 4.
Specimens were formulated for each property assessment to characterize the composite materials. Cylindrical specimens with dimensions of (20 × 50 mm) were produced to measure the thermal conductivity and diffusivity, whereas another set with dimensions of (30 × 60 mm) was used for compressive strength testing. The same cylindrical specimens were used to evaluate the density.

2.2. Characterization Techniques

A range of tests and methods were employed to execute the experimental protocols for various formulations. The hot-disk method proved to be indispensable for thermal conductivity and diffusivity characterization. This technique facilitates the precise measurement of thermal properties across a wide array of materials, including liquids, powders, solids, and composites, in accordance with the ISO 22007-2 standards [28]. Using a cylindrical probe with a radius of 2 mm, specifically the Kapton 5501 Gray Cable type (max 50 °C), the thermal conductivity and diffusivity of the different formulations were determined.
Compressive strength testing was conducted on cylindrical samples prepared as previously discussed using a hydraulic press machine (Testweell) with a 20 kN capacity. The resistance to compression was calculated using Equation (1).
Rc = Fc/S
where Rc represents the compressive strength (MPa), and Fc and S denote the maximum load at the fracture and surface area of the tested specimens, respectively.
Density determination ρ was performed using Equation (2), where m represents the dry weight at 28 days in kilograms, and V denotes the volume of the specimens in cubic meters. Weight was measured on a balance with an accuracy of ±0.1 g, and specimen dimensions were ascertained using a ruler with a minimum count of ±0.5 mm.
ρ = m/V

3. Results and Discussion

3.1. Density

The findings in Figure 5 indicate a decrease in the mixture density as the clay content increased, which is attributed to the increased voids within the cement matrix [14]. This decrease aligns with the lower density of clay (768 kg/m3) compared with Portland cement (1116 kg/m3). For instance, comparing M30 and M0 formulations reveals a translation in density from 2115 to 2049 kg/m3 owing to 30 wt% clay replacements. This reduction is comparable with commonly used SCMs, such as FA. For instance, in the study by Wang et al. [29], the progressive introduction of coal waste from 0% to 45% resulted in a decrease in density from 2488 kg/m3 to 2190 kg/m3; the authors primarily attribute this decrease in density to the increase in porosity. The reduction in density offers significant advantages, such as reducing labor requirements and raw material consumption, as well as positively impacting fuel consumption and greenhouse gas emissions [30].

3.2. XRD Analysis

XRD analysis is commonly employed to determine the mineralogical composition of blended cement pastes, offering insights into phase composition and hydration progress over time [31]. In this study, XRD was used to characterize the cement–clay blend, which was cured for 28 days. Figure 6 displays the resulting spectra, which show prominent peaks corresponding to quartz (Q), Portlandite (CH), calcite (CC), and calcium silicate hydrate (CSH). The presence of tricalcium silicate (C3S), a non-hydrated cement phase, is also notable.
The presence of calcite is primarily attributed to the calcareous sand used, which contains over 50% calcite. As the clay content in the cement paste increases from M5 to M30, there is a marked rise in the intensity of quartz peaks. This trend can be explained by the fact that raw clay is rich in crystalline SiO2, contributing a stable quartz phase to the matrix without undergoing significant reaction at standard curing temperatures.
This stable presence of quartz supports the notion that raw clay acts as a passive additive, enriching the composite with quartz while minimally interacting with active cementitious phases such as Portlandite and CSH gel. The lack of significant changes in other hydration phases reinforces the understanding that quartz remains largely inert in this blend. From a mechanical perspective, the stable incorporation of quartz can be advantageous, as quartz is known to enhance dimensional stability, reduce shrinkage, and improve overall durability and resistance to wear and abrasion, contributing to the long-term structural performance and resilience of cement-based materials [32,33,34].

3.3. Compressive Strength

Figure 7 shows the compressive strength of various formulations. Although adding clay progressively reduces strength over time, its effect at one day remains negligible, which is beneficial for urgent projects. Notably, the M20 formulation retains a strength similar to the reference mix despite a 20% cement substitution, making it particularly advantageous in time-sensitive applications. However, after 28 days of curing, compressive strength reductions of 10.9%, 26.7%, 41.1%, 56.8%, 55.7%, and 63.7% were recorded for the M5, M10, M15, M20, M25, and M30 formulations, respectively. These results align with those of previous investigations [35,36], including Nwaubani et al. [21], who observed a decrease in compressive resistance from 41 to 28 MPa with a 15% introduction of raw kaolin clay as a cement substitute. Ahmad et al. [22] also reported reduced compressive strength with increased raw bentonite content, with a 30% bentonite inclusion resulting in a 70% strength reduction compared to the control mix after 56 days.
This decline in strength can be attributed to the tendency of raw clay to coat cement particles while absorbing mixing water [37], increasing water demand, and impeding hydration kinetics, thereby diminishing compressive strength evolution.

3.4. Thermal Properties

Figure 8 presents the thermal transport properties of the unfired clay-based mortar. The results indicate that red clay enhances thermal insulation, as both thermal conductivity and diffusivity decrease with increasing clay content. For instance, a clay addition of 5 wt% reduced thermal conductivity and diffusivity by 3.4% and 2.54%, respectively. With 30 wt% clay, these values decreased further, from 0.88 to 0.81 W/m·K and from 0.55 to 0.44 mm²/s, respectively, reflecting improvements of 8.18% in thermal resistance and 20% in diffusivity. Similar findings are reported by Serina et al. [38], who observed a 20% reduction in thermal conductivity with calcined clays used as cement replacements, while Charai et al. [39] attribute these reductions in density and thermal conductivity to increased microstructural porosity. Additionally, red clay’s highly porous, multilayered honeycomb structure, with substantial free space, stores heat (particularly in the far infrared region), which is gradually released at elevated temperatures [40]. This structural porosity is a primary factor contributing to the observed reductions in thermal conductivity and diffusivity.
The specific heat capacity of developed building materials can be calculated using Equation (3), wherein λ is the thermal conductivity (W/m·K), α is thermal diffusivity (mm2/s), and ρ is density (kg/m3). The specific heat capacity, which represent the material’s ability to store heat, is fundamental for predicting thermal comfort level of buildings [41]. The results indicate that increasing the clay content leads to a steady enhancement in the material’s specific heat capacity, culminating in a notable improvement of about 15% at the highest substitution level.
cp = λ/αρ
The rate of heat loss in buildings is significantly influenced by the thermal conductivity, diffusivity, and capacity of concrete. High thermal conductivity and diffusivity result in greater energy loss, as heat transfers quickly through the material. In contrast, a high thermal capacity enables the material to store heat longer, which improves its potential as an insulating agent and minimizes energy loss. This heat retention capability aids in stabilizing indoor temperatures and enhancing energy efficiency. The thermal behavior results in this study demonstrate the potential of raw red clay to enhance both the thermal resistance and heat capacity of buildings when used as a cement replacement. This improvement contributes to greater indoor comfort, increases energy efficiency, and promotes more sustainable building practices.

4. Carbon Emission and Cost Implication Assessment

In general, the utilization of SCMs in cement matrices reduces the costs, environmental impacts, and virgin resource consumption of cement production. This cost reduction occurs because SCMs are less expensive than cement, even when processing like grinding is required [42]. This section discusses the environmental impact and cost implications of the blend produced by combining cement with raw red clay. To focus on this aspect, emissions stemming from water and aggregates are disregarded, as they maintain fixed proportions across all formulations. The CO2 emissions associated with clay range between 0.0017 and 0.0129 kg CO2/kg [43], which is comparable with embodied carbon of limestone. The quantity of CO2 emitted was calculated using Equation (4) and the unit cost was determined using Equation (5):
xCo2 = (CO2-Clay × MClay) + (CO2-Cement × MCement)
where xCo2 represents the quantity of CO2 emitted per formulation (e.g., M5), CO2-Clay and CO2-Cement denote the CO2 emissions per kg of clay and cement, respectively, as outlined in Table 3. MClay and MCement signify the proportions of clay and cement in kilograms per m3 of mortar formulation, respectively, as specified in Table 1.
xCost = (CostClay × MClay) + (CostCement × MCement)
where xCost is the estimated cost per formulation, CostClay and CostCement represent the cost of cement and clay in USD per kg, and MClay and MCement are the proportions of clay and cement in kg per m3 of the mortar formulation (see Table 1).
The findings illustrated in Figure 9 indicate that formulations incorporating clay exhibit lower pollution levels and costs. This suggests that the gradual replacement of cement by clay leads to a progressive decrease in carbon emissions and cost of cementitious materials. The study reveals that replacing 30% of cement results in a 30.7% reduction in CO2 emissions and yields savings of approximately USD 120 per ton. Given that economic and environmental impacts are key factors in the durability of cementitious materials, the use of clay contributes significantly to enhancing construction sustainability.

5. Optimal Formulation and Potential Applications

For applications requiring low mechanical strength, substituting more than 5% clay offers multiple advantages. These materials are lighter, and the incorporation of a significant amount of clay in mortar improves thermal resistance by approximately 8%, while reducing costs and CO2 emissions by up to 19% and 30.7%, respectively. Such formulations are particularly suitable for finishing applications, where low density and high thermal resistance are desired to enhance building thermal comfort, especially in extreme climate regions [47].
For applications requiring high mechanical strength, introducing clay up to a maximum of 5% is more appropriate. This substitution only slightly affects compressive strength while significantly improving thermal resistance. It also allows for reductions in future construction costs and emissions by around 3.3% and 5.18%, respectively, making it a viable choice for masonry mortars. This type of formulation can thus be used in the construction of walls and structures requiring good compressive strength and thermal durability, particularly in environments exposed to temperature fluctuations and humidity.
Additionally, raw red clay is notably rich in quartz, as revealed by X-ray diffraction (XRD) results. This quartz content makes this clay ideal for applications requiring increased durability under conditions of humidity or freeze–thaw cycles, as well as resistance to thermal shock. These properties are especially valuable in sustainable construction and insulation sectors, where they contribute significantly to cost and environmental impact savings [32,48].

6. Conclusions

This study examined the impact of red clay as a supplementary cementitious material on the density, thermal conductivity and diffusivity, and compressive strength of mortar while also assessing its economic and environmental implications. The findings suggest that raw clay has the potential to enhance the thermal properties of concrete and decrease the cost of materials and Co2 emissions, positioning it competitively among other cementitious materials for applications requiring low-grade strength concrete. Two key conclusions emerge from the experimental data:
Incorporating less than 5% by weight of raw clay into the mortar had minimal impact on compressive strength while reducing thermal conductivity, diffusivity, cost, and environmental impact. This suggests that such a formulation is well-suited for structural applications where maintaining high mechanical strength is essential.
  • The addition of less than 5% by weight of raw clay into the mortar had minimal impact on compressive strength while reducing thermal conductivity, diffusivity, cost, and environmental impact. This suggests that such a formulation is well-suited for structural applications where maintaining high mechanical strength is essential.
  • Incorporating more than 5% by weight of clay significantly reduced compressive strength but further decreased thermal conductivity and diffusivity, as well as overall costs and carbon emissions. Consequently, this formulation is more appropriate for non-structural applications or scenarios where lower mechanical strength is acceptable.

Author Contributions

M.D.: Conceptualization, methodology, laboratory tests, sample preparation, formal analysis, investigation, resources, writing—original draft, writing—review and editing. O.H.: Conceptualization, methodology, formal analysis, investigation, writing—review and editing, supervision. A.M.: Conceptualization, writing—review and editing, supervision. M.K.: Conceptualization, writing—review and editing. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Data Availability Statement

Data are contained within the article.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Rehman, S.U.; Kiani, U.A.; Yaqub, M.; Ali, T. Controlling natural resources depletion through Montmorillonite replacement for cement-low cost construction. Constr. Build. Mater. 2020, 232, 117188. [Google Scholar] [CrossRef]
  2. Shubbar, A.A.; Jafer, H.; Dulaimi, A.; Hashim, K.; Atherton, W.; Sadique, M. The development of a low carbon binder produced from the ternary blending of cement, ground granulated blast furnace slag and high calcium fly ash: An experimental and statistical approach. Constr. Build. Mater. 2018, 187, 1051–1060. [Google Scholar] [CrossRef]
  3. Keke, L.; Yong, L.; Liuliu, X.; Junjie, Z.; Kangning, L.; Dingqiang, F.; Rui, Y. Rheological characteristics of Ultra-High performance concrete (UHPC) incorporating bentonite. Constr. Build. Mater. 2022, 349, 128793. [Google Scholar] [CrossRef]
  4. Jaskulski, R.; Daria, J. Calcined Clay as Supplementary Cementitious Material. Materials 2020, 13, 4734. [Google Scholar] [CrossRef]
  5. Avet, F.; Scrivener, K. Investigation of the calcined kaolinite content on the hydration of Limestone Calcined Clay Cement (LC3). Cem. Concr. Res. 2018, 107, 124–135. [Google Scholar] [CrossRef]
  6. Tironi, A.; Trezza, M.A.; Scian, A.N.; Irassar, E.F. Kaolinitic calcined clays: Factors affecting its performance as pozzolans. Constr. Build. Mater. 2012, 28, 276–281. [Google Scholar] [CrossRef]
  7. Liu, M.; Hu, Y.; Lai, Z.; Yan, T.; He, X.; Wu, J.; Lu, Z.; Lv, S. Influence of various bentonites on the mechanical properties and impermeability of cement mortars. Constr. Build. Mater. 2020, 241, 118015. [Google Scholar] [CrossRef]
  8. Lai, H.C.; Zhang, J.F.; Li, Y.Y.; Zhou, L.P. Origin and provenance of Red Clay in north Hunan Province, China: Inferred from grain-size analysis and end-member modelling. Aeolian Res. 2021, 51, 100714. [Google Scholar] [CrossRef]
  9. Yu, C.; He, C.-B.; Li, Z.; Li, Y.-A.; Li, Y.; Sun, Y.-L.; Wu, Y.-Q. Disintegration characteristics and mechanism of red clay improved by steel slag powder. Constr. Build. Mater. 2024, 444, 137873. [Google Scholar] [CrossRef]
  10. Yang, S.; Wi, S.; Lee, J.; Lee, H.; Kim, S. Biochar-red clay composites for energy efficiency as eco-friendly building materials: Thermal and mechanical performance. J. Hazard. Mater. 2019, 373, 844–855. [Google Scholar] [CrossRef]
  11. Msinjili, N.S.; Vogler, N.; Sturm, P.; Neubert, M.; Schröder, H.-J.; Kühne, H.-C.; Hünger, K.-J.; Gluth, G.J. Calcined brick clays and mixed clays as supplementary cementitious materials: Effects on the performance of blended cement mortars. Constr. Build. Mater. 2021, 266, 120990. [Google Scholar] [CrossRef]
  12. Janotka, I.; Puertas, F.; Palacios, M.; Kuliffayová, M.; Varga, C. Metakaolin sand-blended-cement pastes: Rheology, hydration process and mechanical properties. Constr. Build. Mater. 2010, 24, 791–802. [Google Scholar] [CrossRef]
  13. Mechti, W.; Mnif, T.; Chaabouni, M.; Rouis, J. Formulation of blended cement by the combination of two pozzolans: Calcined clay and finely ground sand. Constr. Build. Mater. 2014, 50, 609–616. [Google Scholar] [CrossRef]
  14. He, C.; Makovicky, E.; Øsbæck, B. Thermal stability and pozzolanic activity of calcined illite. Appl. Clay Sci. 1995, 9, 337–354. [Google Scholar] [CrossRef]
  15. Sharma, M.; Bishnoi, S.; Martirena, F.; Scrivener, K. Limestone calcined clay cement and concrete: A state-of-the-art review. Cem. Concr. Res. 2021, 149, 106564. [Google Scholar] [CrossRef]
  16. Kočí, V.; Scheinherrová, L.; Maděra, J.; Keppert, M.; Suchorab, Z.; Łagód, G.; Černý, R. Experimental and computational study of thermal processes in red clays exposed to high temperatures. Energies 2020, 13, 2211. [Google Scholar] [CrossRef]
  17. Mousavi, S.S.; Bhojaraju, C.; Ouellet-Plamondon, C. Clay as a Sustainable Binder for Concrete—A Review. Constr. Mater. 2021, 1, 134–168. [Google Scholar] [CrossRef]
  18. Kim, B.J.; Yi, C.; Kang, K.I. Microwave curing of alkali-activated binder using hwangtoh without calcination. Constr. Build. Mater. 2015, 98, 465–475. [Google Scholar] [CrossRef]
  19. Yang, K.H.; Hwang, H.Z.; Kim, S.Y.; Song, J.K. Development of a cementless mortar using hwangtoh binder. Build. Environ. 2007, 42, 3717–3725. [Google Scholar] [CrossRef]
  20. Uddin, M.N.; Saraswathy, V. A comparative study on clay and red soil based geopolymer mortar. Civ. Eng. Archit. 2018, 6, 34–39. [Google Scholar] [CrossRef]
  21. Nwaubani, S.O. Influence of Raw Kaolin Clay and Its Dehydroxylated Form on the Properties and Performance of Portland Cement Mortar. J. Cem. Based Compos. 2022, 4, 5747. [Google Scholar] [CrossRef]
  22. Ahmad, S.; Barbhuiya, S.A.; Elahi, A.; Iqbal, J. Effect of Pakistani bentonite on properties of mortar and concrete. Clay Miner. 2011, 46, 85–92. [Google Scholar] [CrossRef]
  23. Al-Hammood, A.A.; Frayyeh, Q.J.; Abbas, W.A. Raw bentonite as supplementary cementitious material—A review. J. Phys. Conf. Ser. 2021, 1795, 012018. [Google Scholar] [CrossRef]
  24. Rakhimova, N. Montmorillonite clays in Portland clinker-reduced, non-clinker cements, and cement composites: A review. Constr. Build. Mater. 2024, 411, 134678. [Google Scholar] [CrossRef]
  25. NM 10.1.004; Liants hydrauliques ciments et les constituants des ciments: Partie I: Composition, spécifications et critères de conformité; Partie II: Évaluation de la conformité; Partie III: Contrôle de la qualité à la livraison. Institut Marocain de Normalisation (IMANOR): Rabat, Morocco, 2003.
  26. NF P 94-050; Norme Française. Sol: Reconnaissance et Essai. Dé-Termination de la Teneur en Eau Pondérale des Sols. Méthode par Étuvage. AFNOR, 8. AFNOR: La Plaine Saint-Denis, France, 1995.
  27. El Hammouti, A.; Charai, M.; Horma, O.; Mezrhab, A.; Karkri, M. Thermal insulation of mud bricks made with walnut shells: Characterization and simulation study. Mater. Today Proc. 2022, 62, 4545–4550. [Google Scholar] [CrossRef]
  28. ISO 22007-2; Plastics—Determination of Thermal Conductivity and Thermal Diffusivity—Part 2: Transient Plane Heat Source (Hot Disc) Method. International Standard: Geneva, Switzerland, 2022.
  29. Wang, J.; Qin, Q.; Hu, S.; Wu, K. A concrete material with waste coal gangue and fly ash used for farmland drainage in high groundwater level areas. J. Clean. Prod. 2016, 112, 631–638. [Google Scholar] [CrossRef]
  30. Horma, O.; Charai, M.; El Hassani, S.; El Hammouti, A.; Moussaoui, M.A.; Mezrhab, A. Thermal Performance Study of a Cement-Based Mortar Incorporating EPS Beads. Front. Built Environ. 2022, 8, 882942. [Google Scholar] [CrossRef]
  31. Marchetti, G.; Rahhal, V.; Pavlík, Z.; Pavlíková, M.; Irassar, E.F. Assessment of packing, flowability, hydration kinetics, and strength of blended cements with illitic calcined shale. Constr. Build. Mater. 2020, 254, 119042. [Google Scholar] [CrossRef]
  32. Wang, S.; Pang, D.; Chen, S.; Zhang, T.; Bi, W.; Chen, X. Study of Using Quartz Powder as a Mineral Admixture to Produce Magnesium Oxysulfate Cement. Minerals 2023, 13, 1240. [Google Scholar] [CrossRef]
  33. SANI, R. Etude des Transformations Microstructurales de Mélanges Argile/Combustibles Solides de Récupération (CSR) lors de la Cuisson: Relations Entre Propriétés Physico-Chimiques, Mécaniques et Thermiques. 2018. Available online: http://theses.hal.science/tel-02012314v1/document (accessed on 1 November 2024).
  34. Day, K.W. Properties of Concrete; CRC Press: Boca Raton, FL, USA, 2021. [Google Scholar] [CrossRef]
  35. Nehdi, M.L. Clay in cement-based materials: Critical overview of state-of-the-art. Constr. Build. Mater. 2014, 51, 372–382. [Google Scholar] [CrossRef]
  36. He, C.; Osbaeck, B.; Makovicky, E. Pozzolanic reactions of six principal clay minerals: Activation, reactivity assessments and technological effects. Cem. Concr. Res. 1995, 25, 1691–1702. [Google Scholar] [CrossRef]
  37. Budelmann, H.; Hariri, K.; Krauss, H.W.; Malonn, T. Effects of a clay additive on the properties of no-slump concrete. Adv. Constr. Mater. 2007, 2007, 731–739. [Google Scholar] [CrossRef]
  38. Ng, S.; Petter, B.; Stæhli, T. Calcined clays as binder for thermal insulating and structural aerogel incorporated mortar. Cem. Concr. Compos. 2016, 72, 213–221. [Google Scholar] [CrossRef]
  39. Charai, M.; Mezrhab, A.; Moga, L.; Karkri, M. Hygrothermal, mechanical and durability assessment of vegetable concrete mixes made with Alfa fibers for structural and thermal insulating applications. Constr. Build. Mater. 2022, 335, 127518. [Google Scholar] [CrossRef]
  40. Lee, K.C.; Her, J.H.; Kwon, S.K. Red clay composites reinforced with polymeric binders. Constr. Build. Mater. 2008, 22, 2292–2298. [Google Scholar] [CrossRef]
  41. Charai, M.; Sghiouri, H.; Mezrhab, A.; Karkri, M. Thermal insulation potential of non-industrial hemp (Moroccan cannabis sativa L.) fibers for green plaster-based building materials. J. Clean. Prod. 2021, 292, 126064. [Google Scholar] [CrossRef]
  42. Scrivener, K.; Martirena, F.; Bishnoi, S.; Maity, S. Calcined clay limestone cements (LC3). Cem. Concr. Res. 2018, 114, 49–56. [Google Scholar] [CrossRef]
  43. Asdrubali, F.; Grazieschi, G.; Roncone, M.; Thiebat, F.; Carbonaro, C. Sustainability of Building Materials: Embodied Energy and Embodied Carbon of Masonry. Energies 2023, 16, 1846. [Google Scholar] [CrossRef]
  44. Wang, Y.S.; Oh, S.; Ishak, S.; Wang, X.Y.; Lim, S. Recycled glass powder for enhanced sustainability of limestone calcined clay cement (LC3) mixtures: Mechanical properties, hydration, and microstructural analysis. J. Mater. Res. Technol. 2023, 27, 4012–4022. [Google Scholar] [CrossRef]
  45. Kanagaraj, B.; Anand, N.; Raj, R.S.; Lubloy, E. Techno-socio-economic aspects of Portland cement, Geopolymer, and Limestone Calcined Clay Cement (LC3) composite systems: A-State-of-Art-Review. Constr. Build. Mater. 2023, 398, 132484. [Google Scholar] [CrossRef]
  46. U.S. Clay Price 2010–2023|Statista. Available online: https://www.statista.com/statistics/248190/average-price-of-common-clay/ (accessed on 9 November 2024).
  47. Kim, K.W.; Kim, S.; Park, M.J.; Kim, H.J.; Park, J.C. Characteristics of a Reddish Residual Soil (Hwangtoh) finishing material with water-soluble adhesive for residential building. Constr. Build. Mater. 2010, 24, 1542–1546. [Google Scholar] [CrossRef]
  48. Zhang, G.Y.; Oh, S.; Lu, C.; Han, Y.; Lin, R.S.; Wang, X.Y. The Influence of Quartz Powder on the Mechanical–Thermal–Chemical–Durability Properties of Cement-Based Materials. Appl. Sci. 2024, 14, 3296. [Google Scholar] [CrossRef]
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Figure 1. Particle size distribution of raw materials.
Figure 1. Particle size distribution of raw materials.
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Figure 2. XRD pattern of clay.
Figure 2. XRD pattern of clay.
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Figure 3. Appearance morphology and EDS spectra of red clay.
Figure 3. Appearance morphology and EDS spectra of red clay.
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Figure 4. Sample preparation process.
Figure 4. Sample preparation process.
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Figure 5. Density versus clay content.
Figure 5. Density versus clay content.
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Figure 6. XRD spectra of clay-based paste after 28 days of curing, showing the presence of quartz (Q), Portlandite (CH), calcite (CC), calcium silicate hydrate (CSH), and tricalcium silicate (C3S).
Figure 6. XRD spectra of clay-based paste after 28 days of curing, showing the presence of quartz (Q), Portlandite (CH), calcite (CC), calcium silicate hydrate (CSH), and tricalcium silicate (C3S).
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Figure 7. Compressive strength after 28 days of curing versus various formulations.
Figure 7. Compressive strength after 28 days of curing versus various formulations.
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Figure 8. Thermal properties versus various formulations.
Figure 8. Thermal properties versus various formulations.
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Figure 9. Carbon emissions (a) and unit costs (b) of blended cement at different replacement levels.
Figure 9. Carbon emissions (a) and unit costs (b) of blended cement at different replacement levels.
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Table 1. Chemical composition of red clay determined by XRF.
Table 1. Chemical composition of red clay determined by XRF.
OxidesSi2O2Al2O3Fe2O3K2OCaOTiO2P2O5SrOZrO2V2O5
Weight %50.4319.8815.965.872.31.9610.210.10.08
Table 2. Specimens proportion in weight percent and kg/m3.
Table 2. Specimens proportion in weight percent and kg/m3.
SampleClayCement Sand Water to Cement Ratio
wt%kg/m3wt%kg/m3wt%kg/m3
M000100456.13701064.310.5
M5522.5995429.34701064.310.5
M101044.7890403.05701064.310.5
M151566.5785377.23701064.310.5
M202087.9680351.87701064.310.5
M2525108.9875326.96701064.310.5
M3030129.6370302.48701064.310.5
Table 3. Unit costs and CO2 emissions of clay and cement.
Table 3. Unit costs and CO2 emissions of clay and cement.
MaterialsCO2 Emission (kg·Co2/kg) [44].Disposal Cost ($/kg) [45,46].
Cement0.8630.13
Clay0.0080.017
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Drissi, M.; Horma, O.; Mezrhab, A.; Karkri, M. Exploring Raw Red Clay as a Supplementary Cementitious Material: Composition, Thermo-Mechanical Performance, Cost, and Environmental Impact. Buildings 2024, 14, 3906. https://doi.org/10.3390/buildings14123906

AMA Style

Drissi M, Horma O, Mezrhab A, Karkri M. Exploring Raw Red Clay as a Supplementary Cementitious Material: Composition, Thermo-Mechanical Performance, Cost, and Environmental Impact. Buildings. 2024; 14(12):3906. https://doi.org/10.3390/buildings14123906

Chicago/Turabian Style

Drissi, Mohammed, Othmane Horma, Ahmed Mezrhab, and Mustapha Karkri. 2024. "Exploring Raw Red Clay as a Supplementary Cementitious Material: Composition, Thermo-Mechanical Performance, Cost, and Environmental Impact" Buildings 14, no. 12: 3906. https://doi.org/10.3390/buildings14123906

APA Style

Drissi, M., Horma, O., Mezrhab, A., & Karkri, M. (2024). Exploring Raw Red Clay as a Supplementary Cementitious Material: Composition, Thermo-Mechanical Performance, Cost, and Environmental Impact. Buildings, 14(12), 3906. https://doi.org/10.3390/buildings14123906

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