Next Article in Journal
Exploring the Landscape of Eco-Innovation: A Bibliometric Analysis of Concepts and Trends in the Manufacturing and Shipbuilding Industries
Previous Article in Journal
The Role of Family Responsibility, Assertiveness, and Networking in Building Female Leadership Aspirations
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
Journals
Sustainability
Volume 16
Issue 12
10.3390/su16125195
sustainability-logo
Submit to this Journal Review for this Journal Propose a Special Issue
► Article Menu

Article Menu

share Share announcement Help format_quote Cite question_answer Discuss in SciProfiles thumb_up
...
Endorse textsms
...
Comment
first_page
settings
Order Article Reprints
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Article

Sustainable Cement Stabilization of Plastic Clay Using Ground Municipal Solid Waste: Enhancing Soil Properties for Geotechnical Applications

by
Jair Arrieta Baldovino
1,*,
Yamid E. Nuñez de la Rosa
2 and
Abdoullah Namdar
3
1
Department of Civil Engineering, Faculty of Engineering, University of Cartagena, Cartagena de Indias 130015, Colombia
2
Faculty of Engineering and Basic Sciences, Fundación Universitaria Los Libertadores, Bogota 1112211, Colombia
3
School of Civil Engineering, Iran University of Science and Technology, Tehran 16846-13114, Iran
*
Author to whom correspondence should be addressed.
Sustainability 2024, 16(12), 5195; https://doi.org/10.3390/su16125195
Submission received: 17 April 2024 / Revised: 12 June 2024 / Accepted: 14 June 2024 / Published: 18 June 2024
Browse Figures
Versions Notes

Abstract

:
The unconfined compressive strength (qu) weakness of low-compressibility clay (CL) reduces its structural safety. As part of the present study, waste glass powder (WGP) was mixed with Portland cement to improve the geotechnical properties of clayey soil, thus contributing to sustainability through the recycling of municipal waste. Based on the stiffness and chemical composite of WGP and cement, the adopted mixing ratio of the mixed soil was 10% and 20% WGP and 3% and 6% cement. The soil mixing ratio was selected and tested considering the percentage of the cement, WGP, water/cement ratio, dry unit weight, porosity of the specimen, and curing times of 7 days and 28 days. SEM-EDS tests were conducted to examine the impact of raw materials on the microstructural mixed soil. The results from SEM-EDS show that the cement–WGP–CL mixture caused different degrees of cementation and bonding products. Modifying multiple layers of water in the particle of the clay surface led to the enhancement of the interaction of the interlayer of hydrated clay, achieving the best unconfined compressive strength and stiffness of the designed specimen. From the viewpoint of unconfined compressive strength and stiffness enhancement, blending content of 20% WGP and 6% cement and dry unit weights compaction was recommended for stabilizing CL. The process of qu and stiffness improving CL involved an optimized mixing ratio and particle densification reaction efficiency. The soil’s qu and stiffness were predicted using ANN (artificial neural networks) and the porosity/cement index was predicted based on the experimental results.

1. Introduction

Expansive soil is categorized by a high expansion volume, extraordinary shrinkage level, and low bearing capacity, and it is comparable to the general clay. In addition, expansive soil causes failures of the numerous types of footings and slopes with any geometry [1,2,3,4]. Expansive soil exhibits the development of extreme and permanent deformation in road structure [5,6]. Highly plastic clay is one of the expansive soil types containing montmorillonite and is known as a problematic soil type because of its high moisture content, leading to low qu [7,8,9,10]. Considering the above problem, constructing infrastructures on highly plastic clay is usually unacceptable. To minimize instability in soil foundations and infrastructures resting on highly plastic clay, mixed soil designs using different types of soils available in the construction site are the primary option for improving the highly plastic clay [10] Unfortunately, this type of soil improvement is associated with limitations relative to the improvement of soil quality. A suitable soil improvement method is encouraged to enhance the mechanical properties of highly plastic clay. In addition, the application method is sufficiently suitable if it supports the minimization of environmental pollution. Construction activities in geotechnical engineering must support environmental health quality by presenting a viable method.
The mechanical properties of the high-plasticity clay have been improved by mixing it with sand and low-plastic silt [11], natural lime and waste ceramic dust [12], crushed limestone waste [7], recycled glass powder waste and dolomitic lime [13], and waste glass powder [14]. Among the different materials used to enhance the mechanical properties of high-plasticity clay, recycled waste glass powder is one of the most sustainable construction materials used to develop a healthy environment without sacrificing quality. Waste glass is a material among the non-biodegradable MSW that is produced in huge quantities [15,16], and waste glass as a non-biodegradable material poses a real threat to the environment [16]. One of the aims of this study was to convert this environmental threat into an opportunity for environmental quality maintenance by introducing a new viable method for highly plastic clay improvement in geotechnical engineering projects.
Waste glass powder [14,17,18,19,20,21], high-density polyethylene and crushed glass powder mixture [22], calcium-carbide–glass-powder mixture [19], recycled glass powder and copper slag mixture [23], and recycled glass powder waste and dolomitic lime mixture [13] have been studied for the improvement of the mechanical properties and stabilization of soil. The microfiber development in the kaolin and bentonite clays by heat improved the hydration of the cement [24]. The MSW materials can be used as cement materials [25,26,27,28,29,30,31], MSW fly ash, waste-derived hydrochars [29], alternative fuels and raw materials as waste management [30], and ground granulated blast furnace slag blended with bentonite [31] to accelerate and strengthen cement hydration. Such experimental work is referred to as cement–WGP–low-plasticity (CL) [32]. In the literature, the cement–WGP–CL mixture has not been reported. The idea of improving the mechanical properties of the soil by using only WGP is not new, but there is potential for extending the method to achieve results of higher quality compared to those available in the literature. By substituting traditional stabilizing agents like cement with recycled glass powder, the demand for natural resources is reduced. This helps conserve natural materials and reduces the environmental impact associated with their extraction and processing.
The porosity/cement ratio (η/Civ) is a relationship between the density and the volumetric amount of cement to describe the mechanical behavior, durability, and stiffness (Go) of artificially stabilized soils (lime, cement, polymers, and natural pozzolans). The η/Civ index was introduced into the literature by Consoli et al. [33] to predict clean sand’s unconfined compressive strength and stiffness. In recent years, the use of the relationship has increased to describe soils stabilized not only with cement or lime, but also with alternative binders. Recently, Bruschi et al. [34] used the η/Civ to study the behavior of sugar cane bagasse ash and carbide lime as a green stabilization technique for bauxite tailings. Al-Subari and Ekinci [35] evaluated cement clay’s qu and Go properties with waste tire inclusions using the porosity/cement factor. The authors concluded that the partial cement replacement with 2.5% of waste tire can be selected as the optimum dosage to improve the cemented clay mechanical properties.
Other studies explore using glass waste materials to improve the engineering properties of problematic soils. Niyomukiza et al. [36] investigated the addition of waste glass powder to expansive clay soils, finding that a 7% incorporation optimally enhances compressive strength and reduces volume changes. Woldesenbet [37] examined black cotton soil stabilization using plastic bottle waste and glass powder, achieving significant improvements in unconfined compressive strength and California bearing ratio, with the best results seen at higher ratios of these waste materials. Ilman and Balkis [38] focused on the mechanical properties of clay stabilized with glass powder and silica fume, demonstrating that a 15% glass powder and 10% silica fume mixture markedly increased compressive and shear strength, confirmed by microstructural analysis. These studies highlight the potential of utilizing waste products for sustainable soil stabilization solutions. By diverting glass waste from landfills and using it in soil stabilization, there is a direct reduction in the volume of waste that needs to be managed in waste disposal sites. This helps mitigate the environmental issues associated with landfill use, such as leachate production and land consumption.
Using waste glass powder in soil stabilization has shown promising results across various studies. Kusuma et al.’s [39] research demonstrates the effectiveness of combining glass bottle powder with steel slag and fly ash to stabilize swamp soil, significantly enhancing its load-bearing capacity. The optimum mix of 5% glass bottle powder with 20% steel slag and 20% fly ash substantially increased the California bearing ratio (CBR) value from 1% to 31%, indicating a robust improvement in soil stability. Similarly, Amiri et al. [40] investigated the potential of recycled glass powder, fired clay brick powder, and eggshell powder to stabilize aeolian sand. The study found that the combination of these materials, mainly when activated with NaOH, resulted in geopolymeric gel formation that increased the qu of the soil, making it suitable for pavement construction with a 91-day qu of 5.32 MPa.
Moreover, Bilgen’s [20] work on the long-term effects of waste glass powder mixed with seawater and lime in clay soils highlighted significant enhancements in compressive strength over extended curing periods. The study noted that the best results were obtained with a 25% glass powder and 5% lime blend, leading to strength increases of up to 23 times, supported by microstructural analyses showing cementitious compound formation. These findings collectively underscore the potential of waste glass powder as a viable material for soil stabilization, offering both environmental and engineering benefits by improving soil properties and supporting sustainable waste management practices.
Recent advancements in the field of cement-based materials have seen significant contributions from studies on the incorporation of graphene oxide (GO) and its derivatives. Yan et al. [41] investigated the dielectric and mechanical properties of cement pastes with magnetically aligned reduced graphene oxide (rGO), demonstrating substantial enhancements in flexural strength and in the dielectric constant due to the aligned rGO orientation. Wang et al. [42] further delved into the dispersion of rGO in cementitious composites, elucidating the importance of effective dispersion schemes in achieving improved mechanical and durability properties of cement mortar samples. Liu et al.’s [43] research focused on the development of bio-inspired cement-based materials by magnetically aligning GO nanosheets in cement paste, showcasing significant improvements in flexural strength and elastic modulus. Together, these studies underscore the potential of incorporating graphene-based materials into cementitious systems to enhance their mechanical, electrical, and durability properties, offering valuable insights for the advancement of sustainable and high-performance construction materials.
In the present study, the methodology that is presented, consisting of the densification of the specimen and the application of compaction with different densification points to the cement–WGP–CL mixture, is a new idea. In addition, the application of the proposed method in cement–WGP–CL has not been reported in the literature. Also, the proportion of cement–WGP–CL designed in this study is new. The impact of the glass powder on the cement hydration of the designed mixture and the mechanism of the compaction that governs the microstructural modification of spacemen still need to be studied in more detail. Considering the chemical properties of the cement–WGP–CL material and the impact of the mixture design, the qu and stiffness of the proposed cement–WGP–CL mixture need to be investigated. In addition, the experimental results relative to the innovative new materials still need prediction. In this regard, artificial neural networks (ANN) were applied to the experimental results to predict the qu and stiffness of the cement–WGP–CL mixture specimens. The objectives of this study are (1) to assess the impact of the cement–WGP–CL mixture ratio on the qu and stiffness of specimens, (2) to realize the impact of the porosity-to-cement index on the qu and stiffness of specimens, and (3) to investigate different degrees of cementation and bonding products (e.g., silica film and cement hydrates as a portlandite or CH) associated with the curing time and mixture ratio.

2. Experimental Programs

The experimental procedure comprised three sequential stages. Initially, in the first phase, an extensive process was undertaken involving collecting, preparing, and characterizing all utilized materials, namely soil, glass waste, and cement. The characterization encompassed various tests such as determining the granulometric curve of the raw materials, analyzing their chemical composition, microstructure examination, and evaluation of plastic properties for the clay component, alongside the assessment of the specific gravity and density of each raw material. Subsequently, in the second phase, compacted clay specimens were meticulously prepared, incorporating different combinations of added materials based on varying cement-to-WGP ratios. These specimens were then cured within a controlled moist chamber environment to facilitate proper setting and development. Finally, the third and concluding stage involved implementing non-destructive ultrasound tests to elucidate crucial parameters, including stiffness (Go), unconfined compressive strength (qu), and microstructural characteristics of the novel geomaterials. Through these comprehensive assessments, a thorough understanding of the mechanical and structural properties of the developed materials was attained.

2.1. Materials

Clayey soil, Portland cement, WGP, and distilled water were the materials used in this research. The soil was collected near to Cartagena de Indias, Colombia (10°30′21.8″ N 75°28′27.1″ W). The glass residue was collected from a deposition point of waste (windows and bottles) in Cartagena. After being collected, the glass residues were grounded with a planetary mill for 40 min and passed through a 0.1 mm sieve. The properties of the soil and WGP, as well as the standard followed, are shown in Table 1. Additionally, the chemical composition of each material determined through XRF is presented in Table 2. According to the Unified Soil Classification System (USCS) [44], the clay was classified as low-compressibility clay. The specific gravity of CL, WGP, and cement was estimated at 2.80, 2.40, and 3.15, respectively. In addition, Figure 1 provides the size distribution of CL, WGP, and cement particles and the calculation of Cc and Cu.

2.2. Specimen Preparation and WGP–CL Ratios

The specimens were prepared based on the cement–WGP–CL mixture. If CL was subjected to volumetric change, with fluctuations in the moisture content leading to the cracking of CL because of modifications to the mechanical properties of CL, with the appearance of the cracks on CL surface and the possibility of higher CL saturation due to CL’s changing mechanical properties, CL’s strength and stiffness would degrade. It requires explaining why the CL was suitable for this mixture sample design. CL soil or fat clay has a high water-retention capacity compared to the other types of clay soil; this characteristic of CL supports the preparation of the cement–WGP–CL mixture sample. The malleability that is characteristic of CL allowed it to be easily distributed between the cement and WGP in the sample without cracking. Avoiding the cracking of the sample is essential to achieving sufficient strength and stiffness. It has analytically and numerically been reported that the developing crack in the clay soil significantly reduces the stability of the clay. In addition, by applying force on the cracked clay, the crack propagation has been shown to accelerate and extend until the soil model failed, and the expansion and compression of existing soil cracks has been found to influence the compressibility, strain, and stress of the soil [49,50]. Considering this phenomenon, using suitable clay with the appropriate characteristics in the cement–WGP–CL mixture sample design is essential. In addition, during the sample preparation and experimental performance, the maximum moisture content of the sample was maintained to avoid cracks and fissures due to moisture fluctuation. To simplify the experimental procedure, the hydrostatic forces absorbed by the clay were not studied.
Table 3 presents the quantities of cement, WGP, and CL in the specimen mixture design. The optimum moisture content was applied to all specimens (i.e., 18%). Table 3 and Figure 2 show the cement–WGP–CL mixture sample design. The percentage of the basic materials used to prepare the sample is presented in Table 3. In addition, the compaction method played a crucial function in the experimental procedure. Seventy-two experiments were performed, considering the optimum moisture content at each test to reach the model’s maximum qu and stiffness through appropriate hydration. The 7 days and 28 days of the curing time were the target for preparing the specimens under the maximum dry density (i.e., γd = 17.6 kN/m3) for testing. However, two other dry densities above and below the maximum were considered to study the influence of porosity changes. The cement and CL were the primary materials for the cementation of the specimens. In the cement–WGP–CL mixture design, 3% and 6% cement were used. The percentages of cement were chosen by taking into account the fact that the maximum average value for clay soils with low plasticity (such as that of the present study) is 6% according to international standards [51,52]. Furthermore, in recent studies, these percentages have been used [53,54,55]. Compaction point 1 (γd = 17 kN/m3), point 2 (γd = 17.6 kN/m3), and point 3 (γd = 18 kN/m3) were applied to different batches to make specimens ready to execute the required laboratory experiments.

2.3. Experimental Testing

The laboratory experiments were designed using raw materials (soil, cement, and glass). The following laboratory experiments were carried out to examine the effect of the cement–WGP mixture on stabilized CL: unconfined compressive strength (qu) in accordance with ASTM D1633 [56], scanning electron microscopy energy dispersive X-ray analysis (SEM) presented in detail by Roman et al. [7] and conducted using an EDX-720/800HS spectrometer (Smart-Inc., New Smyrna Beach, FL, USA), and ultrasound tests to obtain the stiffness (Go) of the specimen following the American standard ASTM C597 [57]. For unconfined compression, an automated press with a load cell capacity of 5 kN and a deformation sensitivity of 0.01 mm was used at a 1.14 mm/min velocity. For Go recording, an ultrasonic pulse velocity (UPV) device featuring a bandwidth of 20 kHz to 500 kHz and a high measuring resolution of 0.1 microseconds was used. It offers pulse voltages ranging from ± 125 to ± 500 volts and receiver gain options of 1×, 10×, 100×, AUTO, and up to 1000 times. The nominal transducer frequency ranges from 24 kHz to 500 kHz, making it versatile for various applications and ensuring precise, reliable measurements.
Go, qu, and SEM-EDS were performed in relation to each specimen presented in Table 3. Soil moisture is an essential factor impacting soil quality. Increasing soil moisture content decreases the level of qu [58] and the impact of the mixing material ratio on the quantity of the soil. The chemical microanalyses were conducted to reveal the mechanical properties of the specimens. In addition, the dry unit weights (i.e., 17 kN/m3, 17.6 kN/m3, and 18 kN/m3) corresponding to 1-, 2-, and 3-point compaction points were applied to the densifying specimens; finally, the test was conducted for curing times of 7 days and 28 days.

2.4. ANN

Reliable and fast qu measurement of the clay are required to predict the qu of the clay [5]; with limited experimental data, ANNs generated sufficient data for prediction without changing the main data accuracy. In addition, random data were selected from all produced data for the training to have a reliable prediction assessment. ANNs and linear regression analysis are two methods that have been applied to prediction generation in geotechnical engineering with respect to the mixing soil method [59,60]. The data training and reproduction phases are the two main parts of ANNs for the prediction. The results of the laboratory experiment were used for prediction by the ANNs. Seventy-two experimental results were used to predict the qu range of the cement–WGP–CL mixture, considering curing times of 7 days and 28 days.
ANNs [59] and regression analysis [60] have been adopted to predict the mixing soil method results to solve the problem of soil weakness. There is no universal method for explaining ANN architectural design to predict a phenomenon in geotechnical engineering. However, specific parameters are required to understand how to apply the ANN method successfully. The high-quality relationship between prediction and observation is essential to minimize error.
For the prediction of the geotechnical engineering characteristics of the soil mixture, R2 and RMSE provided appropriate measures of the precision of prediction for the safe bearing capacity of the mixed soil results. The cohesion of the mixed soil plays a main role in predicting the safe bearing capacity of the soil mixture [59]. In addition, the linear regression results show how the appropriate soil mixing designs are accompanied by selecting the proper width of a concrete footing, resulting in the development of a safe concrete footing design [60]. ANNs can be suggested for the prediction accuracy of any soil improvement design. ANNs were executed based on the data from the experimental design and performance presented in Table 2. The design of a single hidden layer in ANNs was suggested in the literature, and this method produced acceptable results [61] in the present study; the single hidden layer was designed for the architectural ANN design.
Equations (4) and (5) were adopted [62]: d is the acquired stiffness or qu of the specimens in the laboratory experimental results, dp is the projected stiffness or qu of the specimens using ANNs, and D ¯ o is the mean value of the obtained stiffness or qu of the specimens. The quality of stiffness or qu of the specimen prediction was assessed using Equations (1) and (2):
R M S E = 1 n   ∑ i = 1 n ( d − d p ) 2
R 2 = 1 − ∑ i = 1 n ∑ ( d −   d p ) 2 ∑ i = 1 n ∑ ( d   –   D ¯ o ) 2
For model validation, the training performance needs to be validated after completion of the training phase. In the validation phase, it must be ensured that the model can function within the limits set by the training data. The model should not produce outputs from the input. If the performance of the training and validation phases is acceptable, the model is robust with respect to the prediction. In ANNs, overfitting is likely to take place if the training error is smaller than the validation error [63]. Controlling for overfitting occurrence in relation to ANN outcomes is needed. Figure 3 depicts a designed ANN with a single hidden layer. The input layer includes the curing time, compaction point (dry density), WGP percentage, amount of cement, volumetric water content (Ciw), volumetric cement content (Civ), volumetric content of the sum of WGP and cement (Biv), the porosity/cement index (η/Civ), and the porosity/binder index (η/Biv).

3. Results and Discussions

Mixing glass powder with cement improves soil hydration and provides environmental and economic benefits. Based on the laboratory experimental results, the qu and stiffness of designed cement–WGP–CL mixtures were found to have changed and be associated with curing time, application of compaction points to the specimens, and use of the WGP and cement proportion.

3.1. Unconfined Compressive Strength of Specimens

The qu of stabilized clay of marine origin dramatically improved when the mixture quantity of cement and WGP increased, and the qu reached its maximum level with a higher curing time and mixture quantity of cement and WGP. The poorly densified areas of the specimens exhibited low qu. Increasing the number of densified points increased the specimens’ qu. The three densification points were found (dry unit weights) to give reliable qu to the specimen. Using the appropriate densification method, the expansion level of the cement–WGP–CL mixture decreased, leading to a higher level of qu. In addition, C3S, C2A, and C4AF are all compounds found in cement. C3S, or tricalcium silicate, is the most abundant phase in Portland cement and is responsible for early strength development. C2A, or dicalcium aluminate, contributes to the early setting of the cement. C4AF, or tetracalcium aluminoferrite, contributes to the high early strength of cement. These compounds play important roles in the properties and performance of cement in construction and engineering applications. Over 28 days of curing improved the specimen’s qu, and either 3% or 6% of the cement was used. It is demonstrated that a reconstituted cement–WGP–CL mixture of 20% WGP and 6% cement and three-point compaction in 28 days of curing time improved the ultimate qu and stiffness. Due to this reason, the outcome of this study may be valid for the cement–WGP–CL mixture. Figure 4 illustrates that, in all cases with the increasing number of points, the level of qu increased; this level of qu was achieved by maintaining an optimum moisture content. The hydration process of the cement–WGP–CL mixtures supports achieving peak qu. This process uses multiple layers of water and an interlayer of hydrated montmorillonite.
The hydration behavior of the cement–WGP–CL mixtures in the existing study was evaluated by assessing the function of the multiple layers of water and interlayer of hydrated montmorillonite. The cement–WGP–CL mixtures showed impressive potential as the new method that produces lower CO2 footprint cementitious materials.

3.2. Ultrasound Tests and the Stiffness of the Specimen

According to the results from the ultrasound tests, the specimen stiffness obtained by increasing the compaction energy influenced the microstructural of the cement–WGP–CL mixtures and led to a change in the modulus elasticity of the specimens. There was a direct relationship between the wavelength and the plasticity of the specimen. There was no significant variation in wavelength sizes among the cement–WGP–CL mixture specimens. The curing time and hydration process determined the wavelength. The wavelength was significantly different during the 28 days of curing time compared to that recorded during the seven days of curing for all cement–WGP–CL mixture specimens. The impact of the microstructures of the specimens on the wavelength was apparent.
By comparing Figure 5 with Figure 6, it can be realized that the qu and stiffness of the specimens simultaneously increased when blending 20% WGP and 6% cement and three-point compaction in 28 days of curing time for the cement–WGP–CL mixture design; this proportion of the materials in the mixture is suggestive of an optimum value.
An increase in the strength and stiffness of the soil following densification of the soil [64] is possible by applying the appropriate densification method and using suitable proportions of materials in the design. The compaction points significantly impacted the strain stiffness of the cement–WGP–CL mixture design.
In the mixture of clay, the proportion of glass (20%) was lower than that of the nonrelated clay. Increasing the proportion of glass modified the inter-particle force chain of the clay and decreased the bond to the clay surface; this phenomenon resulted in a reduction in the strength and stiffness of the glass–clay mixture [65]. By introducing the designed cement–WGP–CL mixture, and by supporting the cement hydration process, the qu and stiffness of the cement–WGP–CL mixture significantly increased. The production of cement is highly energy-intensive and contributes significantly to greenhouse gas emissions. Incorporating waste glass powder reduces the amount of cement required, thereby saving energy and reducing the carbon footprint associated with soil stabilization projects.

3.3. Impact of Porosity-to-Cement Index on Strength and Stiffness of Compacted Blends

The impact of densification point number on the porosity of the specimens was associated with the unconfined compressive strength (qu) and stiffness (Go) of specimens. Figure 6 illustrates the porosity/cement index for consideration of compaction points and curing time. The porosity was calculated in accordance with initial molding conditions (i.e., cement content, dry unit weight, WGP, specific gravity of soil, density of WGP). The porosity was calculated using the Baldovino et al.’s [13] formula, and the initial volumetric cement content (Civ) was calculated using the same formula.
According to the statistical analysis for all cases presented in Figure 6, the R2 was above 0.8. This value speaks about the acceptable quality of the experimental results. Based on the initial porosity of the specimen, the microstructure influenced the porosity of the cement–WGP–CL mixtures. The decrease in porosity improved the unconfined compressive strength of the designed mixture, as demonstrated by recent studies [66]. The relationship between the η/ C i v 0.28 and Go is shown in Figure 7. The porosity-to-cement index had a direct relationship with initial stiffness at small deformations. By minimizing the porosity, the initial stiffness increased, resulting in reduced specimen deformation. The cement–WGP–CL mixture sample design influenced the unconfined compressive strength and the initial stiffness at small deformations.
The relationship between qu and Go is shown in Figure 8. Unconfined compressive strength versus the initial stiffness at small deformations were predicted for 7 days and 28 days of curing. By appropriately designing the WGP, the elastic deformation of the sample was controlled for in collaboration with the curing time. The increasing proportion of the WGP impacted the initial stiffness of the specimens at small deformations. According to the prediction analysis, the higher initial stiffness increased with increasing curing time (28 days) and usage (20%) in the cement–WGP–CL mixture sample design. Based on the present study’s findings, the strength and stiffness of the cement–WGP–CL mixture sample can be designed according to the project requirement.

3.4. Microstructure of the Clay Surface and Unconfined Compressive Strength

Figure 9 presents the SEM results of compacted blends. The smectite is the primary reason for the plasticity of the clay. The amorphous silica present in the finely ground glass powder can react with water and calcium hydroxide from cement hydration to form silica gel. Silica gel can contribute to the densification and strengthening of the matrix, as found by several studies about soil–cement–WGP reactions [67,68,69,70]. In the cement–CL–WGP microstructure, molecular interactions occur between the clay surface and the interlayer water and cations [7]. Subsequently, the function of the multiple layers of water is subject to change. The mechanical interaction of the interlayer of hydrated montmorillonite and cement–ground-glass fine particles was responsible for improving the qu of the cement–WGP–CL mixture, as observed by some experimental studies [68,69,70]. As presented in Figure 9a, the unreacted coarse glass particles were evident. Given the small size of the finely ground glass (less than 0.12 mm) utilized in this study, Jani and Hogland [71] emphasized that the pozzolanic properties of finely ground glass become notably enhanced when the particles measure less than 100 µm, a scale similar to that used in this study. In addition, the results from SEM show that the WGP–cement mixture caused different degrees of cementation and bonding in the microstructure of involved substances (Figure 9b) in association with the curing time and compaction method, forming more solid structures with minimized voids. As glass powder contains calcium carbonate, increasing the WGP quantity in the cement–WGP–CL mixture led to higher qu. The calcium carbonate reduced clay plasticity and increased clay qu.
Figure 10 presents the results from the chemical microanalyses on soil–cement–WGP mixtures cured for 7 days and 28 days. Spectrum 1 corresponds to a sample cured for seven days precisely marked over an unreacted ground glass particle within the mixture. The EDS graph shows silica and sodium peaks, both of which are characteristic of glassy materials. As for Spectrum 2, it corresponds to cemented material, as marked in Figure 9b. Figure 10b presents the EDS graph for spectrum 2, showing peaks in cementitious material, such as silica, alumina, calcium, and iron. The findings after 28 days of curing (Figure 9b) show a uniform and nonporous material (i.e., dense structure) with a small content of unreacted WGP particles (anhydrous WGP). In the spaces between the anhydrous WGP, some regions with the appearance of a bonded material were observed, corresponding to the formed reaction products (amorphous gel), as it has also been observed in recent studies on the behavior of soil–cement–WGP compacted blends [20,69]. Figure 9b suggests that the formation of a CH product could be triggered during the early stages of hydration with the dissolution of the aluminate phase of WGP. In a study carried out by Lu et al. [72], the dissolved ions from WGP were conducive to accelerating the hydration of cement and CH formation. In cement-based materials, by magnetically aligning graphene oxide (GO) nanosheets in the cement paste [43], for example, it has been reported that the incorporation of GO enhances the degree of cement hydration and refines the pore structure. In another study with GO inclusions in cement paste, Wang et al. [42] concluded that the hydration products CSH, CH, and ettringite were formed in the paste and alternately stacked after 28 days of curing time, and there were many pores and cracks.

3.5. ANNs and Accuracy Prediction of the Experimental Results

Similarly to the role of laboratory experimental work in predicting stiffness and qu, it is essential to design an appropriate ANN that incorporates the parameters that influence the stiffness and qu of the introduced mixture method. The factors that impacted the stiffness and qu were curing time, compaction points, WGP, cement quantity, Ciw, Civ, Biv, η/Civ, and η/Biv. Table 3 shows data from 72 experimental laboratory experiments used to train the ANN. Figure 3 explains the ANN design. The ANN contained the input, hidden layer, bias, and output. The stiffness and qu were prediction outputs. ANN used backpropagation with 70%, 15%, and 15% of data for training, validation, and testing, respectively. The proportion of allocated data was selected to reduce the prediction error. The prediction accuracy of each ANN is shown in Figure 11 and Figure 12. The comparative prediction between the target and output of the ANN is presented in Figure 11. The prediction accuracy of the ANN was 100% with respect to stiffness and qu values. Notably, the developed ANN could predict stiffness and qu with an overall accuracy of 97% from laboratory experimental results.
Based on the results, the testing, training, and validation errors are presented in Table 4. In the present prediction, no overfitting occurred, considering RMSE for validation and training in stiffness and qu. In addition, the prediction made by the ANN was acceptable. Following application of the ANN, an overview of the prediction model was created with respect to the stiffness and shear strength fluctuation that occurred in all specimens. This prediction was based on all data. Although it is possible to predict every single value for the shear strength and stiffness of the model, based on the mixing soil method, it is more suitable to present an overview of the prediction ability of all models to realize the feasibility of the presented method.

4. Conclusions

According to the performed laboratory experimental outcomes and interpretation of results with the support of available literature, the following conclusions were drawn:
  • The WGP collected from municipal solid waste (MSW) and produced in the laboratory in a mixture with cement can form cementing material. The undrained qu of the best laboratory-manufactured specimen with mixing ratios of 20% WGP and 6% cement and three-point compaction achieved the best performance with respect to qu and stiffness; this level of improvement was adopted to stabilize CL and minimize failure potential. The outcome of this study may be valid for the cement–WGP–CL mixture.
  • In relation to each mixed ratio group, there was a direct relationship between the density mechanism process of the specimen and the level of the qu and stiffness. To avoid errors in estimating unconfined compressive strength, the optimum moisture content was identified for all cement–WGP–CL mixtures.
  • The results from SEM show that the WGP–cement mixture caused different degrees of cementation and bonding in the microstructure of substances in association with the curing time and compaction method, suggesting that the formation of the hydrated product CH could be triggered during the early stages of hydration following dissolution of the aluminate phase of WGP.
  • Improving CL involved an optimized mixing ratio, particle densification reaction efficiency, and modification of the soil matrix. The peak qu and stiffness of the best specimen mixture were associated with increasing calcium carbonate in the cement–WGP–CL mixture.
  • ANN confirmed the experimental results with respect to the prediction of qu and of the stiffness of the cement–WGP–CL mixture specimens.
  • These laboratory experimental results demonstrated the feasibility of this cementing mixture. In future research work, the reuse of WGP in geotechnical engineering may significantly support a reduction of environmental pollution in both directions by using MSW and producing less cement. The cement–WGP–CL mixture is an ideal geotechnical material that can be used in many earthworks. Improving the qu of the subsoil and soil foundation is required in many geotechnical engineering works, and this problem can be solved using a cement–WGP–CL mixture.

Author Contributions

Conceptualization, J.A.B., Y.E.N.d.l.R. and A.N.; methodology, J.A.B., Y.E.N.d.l.R. and A.N.; validation, J.A.B. and A.N.; formal analysis, J.A.B.; investigation, J.A.B., Y.E.N.d.l.R. and A.N.; resources, Y.E.N.d.l.R.; writing—original draft preparation, J.A.B. and A.N.; writing—review and editing, J.A.B. and Y.E.N.d.l.R.; visualization, A.N.; supervision, J.A.B.; funding acquisition, Y.E.N.d.l.R. All authors have read and agreed to the published version of the manuscript.

Funding

The Fundación Universitaria Los Libertadores—Colombia (FULL) (Project No. ING-39-24) funded the APC.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The data presented in this study are available on request from the corresponding author.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Miao, L.C.; Liu, S.Y. Engineering Characteristics of Expansive Soil and Engineering Measures. Adv. Sci. Technol. Water Resour. 2001, 48, 37–40. [Google Scholar]
  2. Liu, Y.; Chang, C.W.; Namdar, A.; She, Y.; Lin, C.H.; Yuan, X.; Yang, Q. Stabilization of Expansive Soil Using Cementing Material from Rice Husk Ash and Calcium Carbide Residue. Constr. Build. Mater. 2019, 221, 1–11. [Google Scholar] [CrossRef]
  3. Ikeagwuani, C.C.; Nwonu, D.C. Emerging Trends in Expansive Soil Stabilisation: A Review. J. Rock. Mech. Geotech. Eng. 2019, 11, 423–440. [Google Scholar] [CrossRef]
  4. Estabragh, A.R.; Parsaei, B.; Javadi, A.A. Laboratory Investigation of the Effect of Cyclic Wetting and Drying on the Behaviour of an Expansive Soil. Soils Found. 2015, 55, 304–314. [Google Scholar] [CrossRef]
  5. AI-Sharif, M.M.; Attom, M.F. A Geoenvironmental Application of Burned Wastewater Sludge Ash in Soil Stabilization. Environ. Earth Sci. 2014, 71, 2453–2463. [Google Scholar] [CrossRef]
  6. Bhattacharja, S.; Bhatty, J.I.; Todres, H.A. Stabilization of Clay Soils by Portland Cement or Lime—A Critical Review of Literature. PCA RD Ser. 2003, 60, 124–133. [Google Scholar]
  7. Román Martínez, C.; Nuñez de la Rosa, Y.E.; Estrada Luna, D.; Baldovino, J.A.; Jordi Bruschi, G. Strength, Stiffness, and Microstructure of Stabilized Marine Clay-Crushed Limestone Waste Blends: Insight on Characterization through Porosity-to-Cement Index. Materials 2023, 16, 4983. [Google Scholar] [CrossRef]
  8. Bjerrum, L. Geotechnical Problems Involved in Foundations of Structures in the North Sea. Geotechnique 1973, 23, 319–358. [Google Scholar] [CrossRef]
  9. Rajasekaran, G.; Narasimha Rao, S. Falling Cone Method to Measure the Strength of Marine Clays. Ocean. Eng. 2004, 31, 1915–1927. [Google Scholar] [CrossRef]
  10. Schmidt, S.R.; Katti, D.R.; Ghosh, P.; Katti, K.S. Evolution of Mechanical Response of Sodium Montmorillonite Interlayer with Increasing Hydration by Molecular Dynamics. Langmuir 2005, 21, 8069–8076. [Google Scholar] [CrossRef]
  11. Aziz, M. Mechanical Properties of a High Plasticity Clay Mixed with Sand and Low-Plastic Silt. Mater. Today Proc. 2023, 19, 1–14. [Google Scholar] [CrossRef]
  12. Beyene, A.; Tesfaye, Y.; Tsige, D.; Sorsa, A.; Wedajo, T.; Tesema, N.; Mekuria, G. Experimental Study on Potential Suitability of Natural Lime and Waste Ceramic Dust in Modifying Properties of Highly Plastic Clay. Heliyon 2022, 8, e10993. [Google Scholar] [CrossRef]
  13. Baldovino, J.J.A.; Izzo, R.L.S.; Rose, J.L.; Domingos, M.D.I. Strength, Durability, and Microstructure of Geopolymers Based on Recycled-Glass Powder Waste and Dolomitic Lime for Soil Stabilization. Constr. Build. Mater. 2021, 271, 121874. [Google Scholar] [CrossRef]
  14. Ibrahim, H.H.; Mawlood, Y.I.; Alshkane, Y.M. Using Waste Glass Powder for Stabilizing High-Plasticity Clay in Erbil City-Iraq. Int. J. Geotech. Eng. 2021, 15, 496–503. [Google Scholar] [CrossRef]
  15. Ashani, P.N.; Shafiei, M.; Karimi, K. Biobutanol Production from Municipal Solid Waste: Technical and Economic Analysis. Bioresour. Technol. 2020, 308, 123267. [Google Scholar] [CrossRef] [PubMed]
  16. Birgen, C.; Magnanelli, E.; Carlsson, P.; Skreiberg, Ø.; Mosby, J.; Becidan, M. Machine Learning Based Modelling for Lower Heating Value Prediction of Municipal Solid Waste. Fuel 2021, 283, 118906. [Google Scholar] [CrossRef]
  17. Ashiq, S.Z.; Akbar, A.; Farooq, K.; Mujtaba, H. Sustainable Improvement in Engineering Behavior of Siwalik Clay Using Industrial Waste Glass Powder as Additive. Case Stud. Constr. Mater. 2022, 16, e00883. [Google Scholar] [CrossRef]
  18. Blayi, R.A.; Sherwani, A.F.H.; Ibrahim, H.H.; Faraj, R.H.; Daraei, A. Strength Improvement of Expansive Soil by Utilizing Waste Glass Powder. Case Stud. Constr. Mater. 2020, 13, e00427. [Google Scholar] [CrossRef]
  19. Pourabbas Bilondi, M.; Toufigh, M.M.; Toufigh, V. Experimental Investigation of Using a Recycled Glass Powder-Based Geopolymer to Improve the Mechanical Behavior of Clay Soils. Constr. Build. Mater. 2018, 170, 302–313. [Google Scholar] [CrossRef]
  20. Bilgen, G. Utilization of Powdered Glass as an Additive in Clayey Soils. Geotech. Geol. Eng. 2020, 38, 3163–3173. [Google Scholar] [CrossRef]
  21. Pourabbas Bilondi, M.; Toufigh, M.M.; Toufigh, V. Using Calcium Carbide Residue as an Alkaline Activator for Glass Powder–Clay Geopolymer. Constr. Build. Mater. 2018, 183, 417–428. [Google Scholar] [CrossRef]
  22. Fauzi, A.; Rahman, W.M.N.W.A.; Jauhari, Z. Utilization Waste Material as Stabilizer on Kuantan Clayey Soil Stabilization. Procedia Eng. 2013, 53, 42–47. [Google Scholar] [CrossRef]
  23. Tajaddini, A.; Saberian, M.; Kamalzadeh Sirchi, V.; Li, J.; Maqsood, T. Improvement of Mechanical Strength of Low-Plasticity Clay Soil Using Geopolymer-Based Materials Synthesized from Glass Powder and Copper Slag. Case Stud. Constr. Mater. 2023, 18, e01820. [Google Scholar] [CrossRef]
  24. Namdar, A. Natural Minerals Mixture for Enhancing Concrete Compressive Strength. Frat. Ed. Integrita Strutt. 2012, 6, 26–30. [Google Scholar] [CrossRef]
  25. Siddique, R. Utilization of Municipal Solid Waste (MSW) Ash in Cement and Mortar. Resour. Conserv. Recycl. 2010, 54, 1037–1047. [Google Scholar] [CrossRef]
  26. López-Zaldívar, O.; Lozano-Díez, R.V.; Verdú-Vázquez, A.; Llauradó-Pérez, N. Effects of the Addition of Inertized MSW Fly Ash on Calcium Aluminate Cement Mortars. Constr. Build. Mater. 2017, 157, 1106–1116. [Google Scholar] [CrossRef]
  27. Saikia, N.; Kato, S.; Kojima, T. Production of Cement Clinkers from Municipal Solid Waste Incineration (MSWI) Fly Ash. Waste Manag. 2007, 27, 1178–1189. [Google Scholar] [CrossRef] [PubMed]
  28. Rémond, S.; Pimienta, P.; Bentz, D.P. Effects of the Incorporation of Municipal Solid Waste Incineration Fly Ash in Cement Pastes and Mortars: I. Experimental Study. Cem. Concr. Res. 2002, 32, 303–311. [Google Scholar] [CrossRef]
  29. Santos, M.M.; Marques Sierra, A.L.; Amado-Fierro, Á.; Suárez, M.; Blanco, F.; La Fuente, J.M.G.; Diez, M.A.; Centeno, T.A. Reducing Cement Consumption in Mortars by Waste-Derived Hydrochars. J. Build. Eng. 2023, 75, 106987. [Google Scholar] [CrossRef]
  30. Aranda Usón, A.; López-Sabirón, A.M.; Ferreira, G.; Llera Sastresa, E. Uses of Alternative Fuels and Raw Materials in the Cement Industry as Sustainable Waste Management Options. Renew. Sustain. Energy Rev. 2013, 23, 242–260. [Google Scholar] [CrossRef]
  31. Devarangadi, M.; Shankar, M.U. Use of Ground Granulated Blast Furnace Slag Blended with Bentonite and Cement Mixtures as a Liner in a Landfill to Retain Diesel Oil Contaminants. J. Environ. Chem. Eng. 2019, 7, 103360. [Google Scholar] [CrossRef]
  32. Sheob, M.; Sajid, M.; Asim Ansari, M.; Rais, I.; Sadique, M.R.; Ahmad, S. Using a Blend of Cement and Waste Glass Powder to Improve the Properties of Clayey Soil. Mater. Today Proc. 2023. [Google Scholar] [CrossRef]
  33. Consoli, N.C.; Foppa, D.; Festugato, L.; Heineck, K.S. Key Parameters for Strength Control of Artificially Cemented Soils. J. Geotech. Geoenviron. Eng. 2007, 133, 197–205. [Google Scholar] [CrossRef]
  34. Bruschi, G.J.; dos Santos, C.P.; Tonini de Araújo, M.; Ferrazzo, S.T.; Marques, S.F.V.; Consoli, N.C. Green Stabilization of Bauxite Tailings: Mechanical Study on Alkali-Activated Materials. J. Mater. Civ. Eng. 2021, 33, 06021007. [Google Scholar] [CrossRef]
  35. Al-Subari, L.; Ekinci, A. Evaluation of Mechanical and Microstructural Properties of Waste Tire Improved Cemented Clay. J. Nat. Fibers 2024, 21, 2349750. [Google Scholar] [CrossRef]
  36. Niyomukiza, J.B.; Eisazadeh, A.; Akamumpa, J.; Kiwanuka, M.; Lukwago, A.; Tiboti, P. Use of Waste Glass Powder in Improving the Properties of Expansive Clay Soils. Glob. Nest J. 2023, 25, 139–145. [Google Scholar] [CrossRef]
  37. Tsegaye Woldesenbet, T. Strength Improvement of Black Cotton Soil Using Plastic Bottles and Crushed Glass Wastes. J. Eng. 2023, 2023, 1–11. [Google Scholar] [CrossRef]
  38. Ilman, B.; Balkis, A.P. Mechanical Properties of Clays Stabilized with Glass Powder and Silica Fume. Int. J. Geosynth. Ground Eng. 2023, 9, 1–6. [Google Scholar] [CrossRef]
  39. Kusuma, R.I.; Mina, E.; Fathonah, W.; Fatwari, M.H.A. Utilization of Waste Steel Slag, Fly Ash, Glass Bottle Powder for Swamp Soil Stabilization. Mater. Sci. Forum 2023, 1101, 109–114. [Google Scholar] [CrossRef]
  40. Amiri, A.; Toufigh, M.M.; Toufigh, V. Recycling and Utilization Assessment of Municipal Solid Waste Materials to Stabilize Aeolian Sand. KSCE J. Civ. Eng. 2023, 27, 1042–1053. [Google Scholar] [CrossRef]
  41. Yan, Y.; Tian, L.; Zhao, W.; Lazaro, S.A.M.; Li, X.; Tang, S. Dielectric and Mechanical Properties of Cement Pastes Incorporated with Magnetically Aligned Reduced Graphene Oxide. Dev. Built Environ. 2024, 18, 100471. [Google Scholar] [CrossRef]
  42. Wang, R.; Sun, R.; Zhao, L.; Zhang, T.; Kong, X.; Fu, Y. Investigation of the Dispersion of Reduced Graphene Oxide in Cementitious Composites under Different Mixing Strategies. J. Build. Eng. 2023, 77, 107447. [Google Scholar] [CrossRef]
  43. Liu, S.; Chen, Y.; Li, X.; Wang, L.; Du, H. Development of Bio-Inspired Cement-Based Material by Magnetically Aligning Graphene Oxide Nanosheets in Cement Paste. Constr. Build. Mater. 2023, 369, 130545. [Google Scholar] [CrossRef]
  44. ASTM ASTM D2487; Standard Practice for Classification of Soils for Engineering Purposes (Unified Soil Classification System). ASTM International: West Conshohocken, PA, USA, 2011; pp. 1–16. [CrossRef]
  45. ASTM ASTM 4318; Standard Test Methods for Liquid Limit, Plastic Limit and Plasticity Index of Soils. ASTM International: West Conshohocken, PA, USA, 2010.
  46. ASTM ASTM D854; Standard Test Methods for Specific Gravity of Soil Solids by Water Pycnometer. ASTM International: West Conshohocken, PA, USA, 2014.
  47. ASTM D7928; Standard Test Method for Particle-Size Distribution (Gradation) of Fine-Grained Soils Using the Sedimentation (Hydrometer) Analysis. ASTM International: West Conshohocken, PA, USA, 2021.
  48. Skempton, A.W. The Colloidal “Activity” of Clays. In Proceedings of the 3rd International Conference on Soil Mechanics and Foundation Engineering, Zurich, Switzerland, 16–27 June 1953; pp. 57–61. [Google Scholar]
  49. Namdar, A.; Karimpour-Fard, M.; Mughieda, O.; Berto, F.; Muhammad, N. Crack Simulation for the Cover of the Landfill—A Seismic Design. Frat. Ed. Integrita Strutt. 2023, 17, 112–134. [Google Scholar] [CrossRef]
  50. Namdar, A.; Karimpour-Fard, M.; Muhammad, N. The Seismic Resistance Simulation for Cracked Clayey Backfill. Eng. Fail. Anal. 2022, 140, 106616. [Google Scholar] [CrossRef]
  51. National Department of Transport. Infrastructure DNIT 143: Pavement Soil-Cement Base-Service Specification; DNIT: Pretoria, South Africa, 2010.
  52. Portland Cement Association. Soil-Cement Laboratory Handbook; Portland Cement Association: Skokie, IL, USA, 2000. [Google Scholar]
  53. Consoli, N.C.; Tomasi, L.F.; Veloso Marques, S.F. Cement-Enhancing Mechanical Behavior of Tailings Behind Upstream Tailings Dam for Safe Decommissioning. J. Mater. Civ. Eng. 2023, 35. [Google Scholar] [CrossRef]
  54. Lade, P.V.; Trads, N. The Role of Cementation in the Behaviour of Cemented Soils. Geotech. Res. 2014, 1, 111–132. [Google Scholar] [CrossRef]
  55. Pham, T.A.; Kyokawa, H.; Koseki, J.; Dias, D. A New Index for the Strength Analysis and Prediction of Cement-Mixed Soils. Eur. J. Environ. Civ. Eng. 2023, 27, 1512–1534. [Google Scholar] [CrossRef]
  56. ASTM D1633-00(2007); Standard Test Methods for Compressive Strength of Molded Soil-Cement Cylinders. ASTM International: West Conshohocken, PA, USA, 2007.
  57. ASTM C597-22; Standard Test Method for Ultrasonic Pulse Velocity through Concrete. ASTM International: West Conshohocken, PA, USA, 2022; pp. 1–4.
  58. Cokca, E.; Erol, O.; Armangil, F. Effects of Compaction Moisture Content on the Shear Strength of an Unsaturated Clay. Geotech. Geol. Eng. 2004, 22, 285–297. [Google Scholar] [CrossRef]
  59. Namdar, A. Forecasting the Bearing Capacity of the Mixed Soil Using Artificial Neural Network. Frat. Ed. Integrita Strutt. 2020, 14, 285–294. [Google Scholar] [CrossRef]
  60. Namdar, A. The Application of Soil Mixture in Concrete Footing Design Using the Linear Regression Model. Mater. Des. Process. Commun. 2021, 3, e179. [Google Scholar] [CrossRef]
  61. Agatonovic-Kustrin, S.; Beresford, R. Basic Concepts of Artificial Neural Network (ANN) Modeling and Its Application in Pharmaceutical Research. J. Pharm. Biomed. Anal. 2000, 22, 717–727. [Google Scholar] [CrossRef] [PubMed]
  62. Namdar, A.; Mughieda, O.; Liu, Y.; Deyu, Y.; Dong, Y.; Chen, Y. Prediction of the Single Pile Seismic Deflection by Using FEM and ANN. Geotech. Geol. Eng. 2023, 42, 2025–2044. [Google Scholar] [CrossRef]
  63. Priddy, K.L.; Keller, P.E. Artificial Neural Networks: An Introduction; SPIE Press: Bellingham, WA, USA, 2005; Volume 68, ISBN 0819459879. [Google Scholar]
  64. Elseifi, M.; Dhakal, N. Lime Utilization in the Laboratory, Field, and Design of Pavement Layers; Department of Civil and Environmental Engieering, Louisiana State University: Baton Rouge, LA, USA, 2017. [Google Scholar]
  65. Perera, M.; Anupiya, S.T.; Saberian, M.; Zhu, J.; Roychand, R.; Li, J. Effect of Crushed Glass on the Mechanical and Microstructural Behavior of Highly Expansive Clay Subgrade. Case Stud. Constr. Mater. 2022, 17, e01244. [Google Scholar] [CrossRef]
  66. Scheuermann Filho, H.C.; Dias Miguel, G.; Cesar Consoli, N. Porosity/Cement Index over a Wide Range of Porosities and Cement Contents. J. Mater. Civ. Eng. 2022, 34, 06021011. [Google Scholar] [CrossRef]
  67. Omran, A.F.; D.-Morin, E.; Harbec, D.; Tagnit-Hamou, A. Long-Term Performance of Glass-Powder Concrete in Large-Scale Field Applications. Constr. Build. Mater. 2017, 135, 43–58. [Google Scholar] [CrossRef]
  68. Arulrajah, A.; Kua, T.-A.; Horpibulsuk, S.; Phetchuay, C.; Suksiripattanapong, C.; Du, Y.-J. Strength and Microstructure Evaluation of Recycled Glass-Fly Ash Geopolymer as Low-Carbon Masonry Units. Constr. Build. Mater. 2016, 114, 400–406. [Google Scholar] [CrossRef]
  69. Consoli, N.C.; da Silva Carretta, M.; Festugato, L.; Leon, H.B.; Tomasi, L.F.; Heineck, K.S. Ground Waste Glass–Carbide Lime as a Sustainable Binder Stabilising Three Different Silica Sands. Géotechnique 2021, 71, 480–493. [Google Scholar] [CrossRef]
  70. Arulrajah, A.; Disfani, M.M.; Haghighi, H.; Mohammadinia, A.; Horpibulsuk, S. Modulus of Rupture Evaluation of Cement Stabilized Recycled Glass/Recycled Concrete Aggregate Blends. Constr. Build. Mater. 2015, 84, 146–155. [Google Scholar] [CrossRef]
  71. Jani, Y.; Hogland, W. Waste Glass in the Production of Cement and Concrete—A Review. J. Environ. Chem. Eng. 2014, 2, 1767–1775. [Google Scholar] [CrossRef]
  72. Lu, J.-X.; Shen, P.; Zhang, Y.; Zheng, H.; Sun, Y.; Poon, C.S. Early-Age and Microstructural Properties of Glass Powder Blended Cement Paste: Improvement by Seawater. Cem. Concr. Compos. 2021, 122, 104165. [Google Scholar] [CrossRef]
Sustainability 16 05195 g001
Figure 1. Granulometric curve of the soil sample, WGP, and Portland cement.
Figure 1. Granulometric curve of the soil sample, WGP, and Portland cement.
Sustainability 16 05195 g001
Sustainability 16 05195 g002
Figure 2. The sample preparation process.
Figure 2. The sample preparation process.
Sustainability 16 05195 g002
Sustainability 16 05195 g003
Figure 3. ANN with inputs, single hidden layer, bias, and output.
Figure 3. ANN with inputs, single hidden layer, bias, and output.
Sustainability 16 05195 g003
Sustainability 16 05195 g004
Figure 4. The average unconfined compressive strength (qu) for cement–WGP–CL mixtures: (a) compacted blends with 10% WGP and (b) compacted blends with 20% WGP.
Figure 4. The average unconfined compressive strength (qu) for cement–WGP–CL mixtures: (a) compacted blends with 10% WGP and (b) compacted blends with 20% WGP.
Sustainability 16 05195 g004
Sustainability 16 05195 g005
Figure 5. The average stiffness for cement–WGP–CL mixtures: (a) compacted blends with 10% WGP and (b) compacted blends with 20% WGP.
Figure 5. The average stiffness for cement–WGP–CL mixtures: (a) compacted blends with 10% WGP and (b) compacted blends with 20% WGP.
Sustainability 16 05195 g005
Sustainability 16 05195 g006
Figure 6. Effects of porosity/cement index on the qu of cement–WGP–CL considering curing time: (a) 7 days of curing and (b) 28 days of curing.
Figure 6. Effects of porosity/cement index on the qu of cement–WGP–CL considering curing time: (a) 7 days of curing and (b) 28 days of curing.
Sustainability 16 05195 g006
Sustainability 16 05195 g007
Figure 7. Effects of porosity/cement index on the stiffness Go of cement–WGP–CL considering curing time: (a) 7 days of curing and (b) 28 days of curing.
Figure 7. Effects of porosity/cement index on the stiffness Go of cement–WGP–CL considering curing time: (a) 7 days of curing and (b) 28 days of curing.
Sustainability 16 05195 g007
Sustainability 16 05195 g008
Figure 8. The direct relationship between qu and Go (i.e., Go/UCS index).
Figure 8. The direct relationship between qu and Go (i.e., Go/UCS index).
Sustainability 16 05195 g008
Sustainability 16 05195 g009
Figure 9. The SEM results of compacted blends: (a) specimen cured under 7 days and (b) specimen cured under 28 days.
Figure 9. The SEM results of compacted blends: (a) specimen cured under 7 days and (b) specimen cured under 28 days.
Sustainability 16 05195 g009
Sustainability 16 05195 g010
Figure 10. The EDS results of compacted blends: (a) specimen cured under seven days (spectrum 1) and (b) specimen cured under 28 days (spectrum 2). Spectrum 1 and spectrum 2 are marked in Figure 10.
Figure 10. The EDS results of compacted blends: (a) specimen cured under seven days (spectrum 1) and (b) specimen cured under 28 days (spectrum 2). Spectrum 1 and spectrum 2 are marked in Figure 10.
Sustainability 16 05195 g010
Sustainability 16 05195 g011
Figure 11. The regression analysis for the prediction of the stiffness and shear strength.
Figure 11. The regression analysis for the prediction of the stiffness and shear strength.
Sustainability 16 05195 g011
Sustainability 16 05195 g012
Figure 12. The best validation of the stiffness and unconfined compressive strength.
Figure 12. The best validation of the stiffness and unconfined compressive strength.
Sustainability 16 05195 g012
Table 1. Characteristics and properties of the soil sample and ground glass. ML is inorganic silt. SW and CL are inorganic clay.
Table 1. Characteristics and properties of the soil sample and ground glass. ML is inorganic silt. SW and CL are inorganic clay.
PropertyStandard/ReferenceUnitValue
CLWGP
Limit liquid, L.L.[45]%42.0-
Plasticity index, P.I.[45]%15.9Non-Plastic
Specific gravity, Gs[46]-2.802.40
Gravel (4.75–76.2 mm)[44,47]%00
Coarse sand (2.00–4.75 mm)[44,47]%00
Medium sand (0.425–2.0 mm)[44,47]%00
Fine sand (0.075–0.425 mm)[44,47]%813
Silt (0.002–0.075 mm)[44,47]%8283
Clay (<0.002 mm)[44,47]%104
Mean diameter (d50)[44,47]mm0.0110.016
Effective diameter (d10)[44,47]mm0.00210.0035
Uniformity coefficient Cu[44,47]-7.145.71
Coefficient of cuvature Cc[44,47]-0.961.03
Activity of clay[48]-1.60-
USCS classification[44]-CLML
colorMunsell Chart-BlackWhite
Main mineralX-ray diffraction-Esmectite and KaoliniteAmorphous
Table 2. Chemical composition of the soil sample, cement, and WGP.
Table 2. Chemical composition of the soil sample, cement, and WGP.
Chemical CompoundChemical Content by Weight (%)
CLPortland CementWGP
CaO3.062.77.1
MgO-3.82.2
SiO266.021.178.2
Al2O321.15.22.2
Fe2O30.92.60.19
TiO20.3--
K2O3.1--
SO34.03.5-
Na2O-0.19.3
MnO-0.2-
P2O5---
LOI1.60.80.7
Table 3. Mixed proportion design for compacted blends of cement–WGP–CL.
Table 3. Mixed proportion design for compacted blends of cement–WGP–CL.
Weight (%)Water Content (%)Curing Times (d)Molding Dry Unit Weigth (kN/m3)Number of Specimens
SoilCementWGP
100310187, 2817, 17.6 and 1818
100320187, 2817, 17.6 and 1818
100610187, 2817, 17.6 and 1818
100620187, 2817, 17.6 and 1818
Table 4. R2 and RMSE outcomes of ANNs for stiffness and shear strength.
Table 4. R2 and RMSE outcomes of ANNs for stiffness and shear strength.
PropertyStatistical ParameterTrainingValidationTestNumber of Layers in ANNs
GoR21111
RMSE0.02280.02040.03841
quR21111
RMSE0.00250.00320.00211
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content.

Share and Cite

MDPI and ACS Style

Baldovino, J.A.; Nuñez de la Rosa, Y.E.; Namdar, A. Sustainable Cement Stabilization of Plastic Clay Using Ground Municipal Solid Waste: Enhancing Soil Properties for Geotechnical Applications. Sustainability 2024, 16, 5195. https://doi.org/10.3390/su16125195

AMA Style

Baldovino JA, Nuñez de la Rosa YE, Namdar A. Sustainable Cement Stabilization of Plastic Clay Using Ground Municipal Solid Waste: Enhancing Soil Properties for Geotechnical Applications. Sustainability. 2024; 16(12):5195. https://doi.org/10.3390/su16125195

Chicago/Turabian Style

Baldovino, Jair Arrieta, Yamid E. Nuñez de la Rosa, and Abdoullah Namdar. 2024. "Sustainable Cement Stabilization of Plastic Clay Using Ground Municipal Solid Waste: Enhancing Soil Properties for Geotechnical Applications" Sustainability 16, no. 12: 5195. https://doi.org/10.3390/su16125195

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop