Soil Strength Research Articles

Research on the Mechanical Properties of EPS Lightweight Soil Mixed with Fly Ash

Expanded polystyrene (EPS) bead–lightweight soil composites are a new type of artificial geotechnical material with low density and high strength. We applied EPS bead–lightweight soil in this project, replacing partial cement with fly ash to reduce construction costs. EPS beads were used as a lightweight material and cement and fly ash as curing agents in the raw soil were used to make EPS lightweight soil mixed with fly ash. The EPS bead proportions were 0.5%, 1%, 1.5%, and 2%; the total curing agent contents were 10%, 15%, 20%, and 25%; and the proportions of fly ash replacing cement were 0%, 15%, 30%, 45%, and 60%, respectively. Unconfined compressive strength (UCS) and scanning electron microscopy (SEM) tests were conducted. The results showed that the EPS content, total curing agent content, and proportion of fly ash replacing cement had a significant impact on the UCS of the lightweight soil. This decreased with an increase in EPS content and decrease in total curing agent content and decreased with increased proportions of fly ash replacing cement. When the proportion of fly ash replacing cement was not too high, the strength of the lightweight soil decreased less, and its performance still met engineering needs. At the same time, the soil can also consume fly ash and reduce environmental pollution. EPS lightweight soil mixed with fly ash still has advantages, and it is recommended to keep the proportion of fly ash replacing cement less than 30%. The failure patterns for lightweight soil mainly include splitting failure, oblique shear failure, and bulging failure, which are related to the material mix ratio.

Study on the Macro-/Micrometric Characteristics and Mechanical Properties of Clayey Sandy Dredged Fill in the Guangdong Area.

The study of dredged fill in Guangdong (GD), China, is of great significance for reclamation projects. Currently, there are relatively few studies on dredged fill in Guangdong, and there are many differences in the engineering characteristics of dredged fill foundations formed through land reclamation and natural foundations. In order to have a more comprehensive understanding of the physico-mechanical properties of blowing fill in the coastal area of GD and to understand the effect of its long-term creep row on the long-term settlement and deformation of buildings, the material properties, microstructure, elemental composition, triaxial shear properties, and triaxial creep properties of dredged fill in Guangdong were studied and analyzed through indoor geotechnical tests, scanning electron microscopy (SEM), X-ray diffraction (XRD), and conventional triaxial shear tests and triaxial creep tests. The test results showed that the Guangdong dredged fill is characterized by a high water content, high pore ratio, and high-liquid-limit clayey sand, and the mineral composition is dominated by quartz and whitmoreite. The scanning electron microscopy results showed that the particles of the dredged fill showed an agglomerated morphology, and the surface of the test soil samples had scaly fine flakes and a fragmented structure. In the triaxial shear test, the GD dredged fill showed strain hardening characteristics, and the effective stress path showed continuous loading characteristics; the consolidated undrained shear test showed that the GD dredged fill had shear expansion characteristics under low-perimeter-pressure conditions. It was found that, with an increase in bias stress, the axial strain in the consolidated undrained triaxial creep test under the same perimeter pressure conditions gradually exceeded the axial strain in the consolidated drained triaxial creep test. The results of this study are of theoretical and practical significance for further understanding the mechanical properties of silty soils in the region and for the rational selection of soil strength parameters in practical engineering design.

Study of the Shear Strength Model of Unsaturated Soil in the Benggang Area of Southern China

Benggangs are a unique type of soil erosion commonly found in southern China, with the gully wall being the most dynamic component of the Benggang system and is crucial for assessing its overall progression. The unsaturated shear strength of soil in Benggang areas is a key factor influencing the stability of the gully wall. However, quantitative analyses of the unsaturated shear strength in the gully walls of Benggangs remain limited. In this study, the soil–water characteristic curves (SWCC) and shear strengths of undisturbed soil samples from four different soil layers in the gully wall of Benggang were measured using a pressure membrane meter and a quadruple direct shear apparatus. The results revealed that the water holding capacity of the soil decreased gradually with increasing matrix suction, and the order of the water holding capacity was the sandy soil layer > transition layer > laterite layer > clastic layer. With an increasing soil water content (SWC), the shear strength, cohesion (c), and internal friction angle (φ) of the four soil layers decreased significantly, and the φ showed a power function decreasing curve (p < 0.05), whereas c in the laterite layer and transition layer exhibited a power function decreasing curve (p < 0.01). The c of the sandy soil layer and clastic layer decreased linearly and logarithmically (p < 0.01) with increasing SWC, respectively. The unsaturated shear strength model for the four soil layers was developed based on the Vanapalli model. The root mean square error (RMSE) of the simulated and measured values was less than 29.349, while the Nash–Sutcliffe efficiency (NSE) and R2 values were greater than 0.638 and 0.788, respectively. The model can be used to analyze and predict the unsaturated shear strength in different layers of Benggang gully walls, providing a theoretical foundation for studying the erosion mechanisms of Benggangs.

Laboratory experimental study on GESC combined with electroosmosis for ground improvement

To verify the effect of electrokinetic geosynthetics-encased stone columns combined with electroosmosis on soft soil foundation reinforcement, laboratory model experiments were conducted using stone columns (SC), geosynthetics-encased stone columns (GESC) with/without electroosmosis. The energy consumption coefficient and drainage rate of electroosmosis, the shear strength and water content distribution of soil, and deformation law of the pile section after static load tests at different depths were studied. Experimental results show the strength of soil around the pile increases after electroosmosis, enabling better support for the pile body, while the pile-soil stress ratio of the gravel pile is reduced and the side friction resistance is effectively exerted. Moreover, the expansion deformation distribution of the gravel pile in both the E-GESC and GESC configurations is basically the same, and the maximum radial deformation is less than that observed in the SC. Most of the deformation occurs within a range of 2 times the pile diameter below the boundary line of the wrapped section. The ultimate bearing capacity of the composite foundation formed by the electroosmosis with geosynthetics encased stone columns (E-GESC) method is 6.6 times that of the SC and 3.8 times that of the GESC, demonstrating a significantly enhanced reinforcement effect.

Evaluating the Strength and Durability Properties of Geopolymer-Stabilized Soft Soil for Deep Mixing Applications

Soft soil poses serious challenges and is unsuitable for engineering projects because of its insufficient bearing capacity, low shear strength, and high compressibility. Deep soil mixing (DSM) is one of the most popular methods of enhancing soft soil qualities, such as increased bearing capacity and reduced settling, which are critical for building any structure. The environmental effects of creating binders such as cement and lime make it crucial to identify alternative materials for geotechnical applications. This study employed fly ash (class C) --based geopolymer to investigate its effectiveness as an environmentally friendly substitute for cement for DSM applications. The experimental program included unconfined compressive strength, flexure strength, and durability tests. The parameters in the study are binder content (10, 15, and 20%) and activator/binder ratio (0.4, 0.6). Results revealed that UCS and flexural strength, GP-treated soil were in the range of 0.9–5.3 and 0.8–1.5 MPa, respectively (depending on the ratio of fly ash and activator). These strengths were even higher than those of cement-stabilized soil. The geopolymer-treated specimens exhibited excellent endurance over the wetting-drying cycle, with a modest weight loss of less than 4.5%. A binder dosage of more than 10% and an AC ratio of 0.6 were recommended to meet DSM application guidelines. The current study concludes that employing a fly ash-geopolymer binder to stabilize soft soil is an effective alternative to cement in DSM applications.

Soil Strength Parameters for the Sustainable Design of Unsupported Cuts Under Drained Conditions Using Reliability Analysis

Unsupported excavations are frequently performed in several geological and geotechnical projects, particularly for constructing roads and railways, and they are often carried out in different materials. The design of such cuts in soils needs the determination of representative values of its mechanical properties, particularly of the strength parameters, and the application of adequate safety factors. The procedure should ensure a sustainable design of those cuts, allowing for economical solutions that guarantee a low probability of geological–geotechnical failure. This paper assesses the reliability of unsupported cuts in soils, under drained conditions, assuming a Mohr–Coulomb strength criterion. Statistical meshes are generated considering the spatial variability of the friction angle and of the true effective cohesion, which are assumed to be uncorrelated. In this process, typical values of the coefficients of variation and of the horizontal and vertical scales of fluctuation are applied. Soil characterisation is simulated in each statistical mesh, and the characteristic values of the strength parameters are determined using statistical methods. Unsupported cuts of different heights and inclinations are designed using typical safety factors. Slope stability analyses are carried out using Random Finite Element Limit Analysis. The uncertainty in the actions is considered, and the probability of failure is determined by direct reliability analysis. The results show the relevance of the ratio between the scale of fluctuation and the excavation depth, the slope inclination, and the characteristic value of the soil strength parameters on the probability of failure. Values of adequate safety factors are proposed towards obtaining an appropriate probability of failure, compatible with the sustainable design of the cuts.

Analysis of the Effects of Temperature and Treatment Duration on the Resistance of Expansive Soil Improved with Lime in Baghdad, Iraq

Multiple studies have revealed the challenge of constructing infrastructure on expansive soils, including pipelines, roads, or buildings. This predicament stems from the uneven moisture distribution inherent to the specific soil type. Numerous methods, involving the addition of chemicals, have been employed to enhance the properties of clayey soils. This study introduces lime as a cation exchange material and demonstrates its capacity to improve the load-bearing characteristics, rendering it a more favorable option for engineering construction purposes. Lime's reaction with clay minerals and water produces calcium hydroxide, which subsequently reacts with the silica and alumina in the clay to form new compounds that promote stability. Additionally, lime helps reduce the soil's water-holding ability, thereby decreasing its swelling potential. This research will focus on evaluating the influence of temperature and treatment duration on the osmotic pressure behavior of chemically treated expansive clayey soils using lime. The swell meter test was utilized to develop lime-clay samples containing 7% lime by dry weight. These samples were then subjected to compression at temperatures ranging from 20 °C to 40 °C over a period of up to 28 days. The findings indicate that the pozzolanic reaction results in higher compressive strengths when tested at the upper limits of the temperature range in laboratory experiments. Therefore, the combined effects of temperature and curing duration play a positive role in improving the compressive strength of expansive soils.

Wildfire burn severity and post-wildfire time impact mechanical and hydraulic properties of forest soils

Vegetation contributes to the overall slope stability and is recognized as an environmentally friendly nature-based solution. Wildfires burn and denude vegetated slopes, thus increasing the risk of shallow landslides and debris flows. However, little attention has been given to assessing the effects of burn severity and the time elapsed since a wildfire on the hydro-geomechanical properties of burned slopes. This study performed a series of standard laboratory tests to evaluate the shear strength and saturated hydraulic conductivity (ksat) of forest soils collected from moderate-low (ML) burned, moderate-high (MH) burned, and unburned (UB) test plots. The plots were sampled one, four, and six months after the March 2022 wildfire in Uljin County, South Korea. The results show that the continuous deterioration of roots highly depended on the burn severity. The root biomass of ML- and MH-burned soils was consistently lower than those of the UB soils. The root deterioration reduced the shear strength of the soils temporally. The burned soil's cohesion intercept was 1.80–2.30 times lower than that of the UB soil six months post-wildfire, with the friction angle unaffected. One- and four-months post-wildfire, ksat of the burned soils was 1.22–3.15 times lower than the UB soil. Such lowered ksat was due to the fine ash-clogged pores and hydrophobic layers beneath the soil surface. However, six months post-wildfire, the burned soils' ksat increased by approximately twice that of the pre-wildfire condition because of macropore flow passages formed by impoverished roots. The appreciation of sand fraction, depreciation of fines content, and weakening of hydrophobicity over time have also emphasized their role in the temporal shifts in the properties of the ML- and MH-burned soils. The documented results herein can be incorporated into rainfall infiltration and stability analyses of wildfire-affected slopes, landslide susceptibility mapping, and mitigation measures design.

Freeze-thaw durability of clayey soils stabilized by alkaline-activated kaolin and recycled cement kiln dust

Weak soils pose significant challenges for civil engineering projects, particularly in cold regions. Stabilizing such soils with additives is a common practice to enhance their geotechnical properties. This research aimed to evaluate the durability of clayey soils stabilized by alkaline-activated kaolin at 10, 25, and 50%, along with 10% recycled cement kiln dust (CKD). The stabilization process involved curing the soils at different temperatures (40, 60, and 80°C) for varying durations (1, 7, 14, and 28 days). The stabilized soils underwent 5, 10, and 20 freeze-thaw (F-T) cycles to evaluate their durability. The results indicated F-T cycling led to a reduction in the unconfined compressive strength (UCS) of unstabilized soils, with a more pronounced impact as the number of cycles increased. However, this adverse effect was mitigated by additive stabilization. The improvement in UCS in stabilized soils was directly linked to the additive content, curing duration, and temperature. Both additives demonstrated superior resistance to F-T cycles, with CKD outperforming kaolin. These findings provide guidelines for utilizing kaolin and CKD for earthwork applications in cold regions with economic and sustainability advantages.

Utilisation of Class-F fly ash in xanthan gum–amended neutral or acidic soils

Xanthan gum (XG) is an eco-friendly biopolymer with potential applications in soil amendment. However, in acidic soil environments, the pyruvate groups and glycosidic bonds in XG molecules tend to hydrolyse, thereby weakening the efficacy of soil improvement. In this study, the feasibility of utilising alkaline Class-F fly ash (FA) to assist XG in reinforcing acidic soils was evaluated through proctor compaction, unconfined compression, and one-dimensional consolidation. With the increasing soil acidities, the beneficial effect of FA on the geotechnical performances of XG-amended soils grew. The improvement in both mechanical strength and compressibility of XG-amended acidic soils might be caused by the crossing-linking of XG molecular strands and the mitigated hydrolysis of XG hydrogels due to the presence of FA. Based on the findings, it is suggested to use FA in combination with XG for treating the acidic soils and use XG alone for treating the neutral soils. The research outcomes will promote the reuse of solid waste Class-F FA in sustainable geotechnical engineering practices, for example, biopolymer-based soil amendment in acidic soils.

Stress-strain ratio on stabilization work in the saturated zone causes rapid road failure

Abstract Road construction frequently encounters difficulties with soil with low bearing capacity, such as soil subsidence, which results in the deformation or waves of the surface road. The investigation was conducted at the Paya Tumpi quarry and quarry in Krueng Raya-Laweung, which are the providers of soil material used in road construction. These two quarries, due to their extensive clay soil criteria, are unsuitable for use as road subgrade material. Hence, to utilize this soil, it is necessary to stabilize it by incorporating volcanic ash. This will be accomplished by evaluating the shear strength of mixed soil, the optimum water content for compaction, and the stress-strain ratio’s behaviour as a result of the stabilization effect. To determine the cohesion and shear angles at a defined shear stress and the response of each test object to strain and stress, a series of experiments were carried out. The research findings indicated that the cohesion and shear angles of the soil samples were enhanced by the addition of volcanic ash in comparison to natural soil. The cohesion (c) of sample-1, sample-2, and sample-3 increased from 0.034-0.223 kg/cm2, 0.093-0.118 kg/cm2, and 0.008–0.037 kg/cm2, respectively. Similarly, the shear angles (ϕ) increase from 32.30o to 40.30o, 27.20o to 30.10o, and 27.90o to 36.20o, respectively. The stress-strain ratio is intermediate between local failure and punching.

Estimation of undrained shear strength of soft clay during surcharge or vacuum preloading

Preloading using either vacuum or fill surcharge is an effective method for the treatment of very soft saturated clay. The preloading will reduce the water content and increase the shear strength of soil. However, when the soil to be treated is very soft, it is difficult to take soil samples for laboratory tests or carry out in situ tests to determine the soil properties including shear strength. Therefore, there is a need to develop an analytical method to estimate the shear strength during preloading. In this paper, a simple correlation among settlement, water content and undrained shear strength using critical state theory is proposed for saturated soil under one-dimensional loading condition to allow the undrained shear strength variation of the soil to be estimated during preloading without testing. Laboratory model test and field monitoring data are used to verify the validity of this method and the proposed correlation is effective to be used as rough estimations on the undrained shear strength of soft clay.

Intelligent characterization and robustness quantification of frozen soil strength images using a multi-module fusion strategy

In frozen wall engineering, traditional detection methods are difficult to implement for real-time monitoring of strength parameters, due to their intermittent nature. This makes it difficult to provide timely warnings and effective responses to potential risks of frozen walls, highlighting the urgent need for a method that can continuously and accurately monitor the strength of frozen walls. An image data-driven intelligent identification method for frozen soil strength based on convolutional neural networks is proposed. By capturing images of cured samples from multiple angles and conducting uniaxial compressive strength tests, the collected strength data were divided into 12 categories, creating an image dataset for deep learning model training. A Resnet-34 deep learning model combined with global attention and downsampling showed excellent performance in comparison with a series of basic models, with an accuracy of 93.3 % and no overfitting. The accuracy of the deep learning model was assessed using adversarial attack and defense strategies, serving as an indicator of robustness. The improved model exhibited better robustness in comparative analyses. Using SHapley Additive exPlanations (SHAP) value analysis, the feature extraction process of the convolutional neural network in recognizing frozen soil strength was investigated and clarified, confirming the model's ability to identify and extract key features in frozen soil images, such as particle size, texture, cracks, and ice crystal distribution patterns. This technology offers a cutting-edge method for real-time tracking of frozen wall conditions and early disaster warnings, significantly enhancing the safety and success rate of construction projects under freezing conditions.

Eco-friendly stabilization of clayey soil with waste glass powder-based geopolymer

ABSTRACT This research studied the feasibility of using waste glass powder, Portland cement, and sodium chloride to stabilise and geopolymerization clayey soil. The chemical composition and microstructure of the materials were determined by X-ray fluorescence and scanning electron microscopy, respectively. Cement and waste glass powder contents were determined through previous laboratory tests and literature reviews. Unconfined compressive strength tests were performed to determine the optimal sodium chloride content, which was used in this research as an alkaline precursor in geopolymer formation. The effects of cement, waste glass powder, and geopolymer (composed of soil+(5 and 15% waste glass powder)+1% sodium chloride) were investigated through unconfined compressive strength and splitting tensile strength tests. The results revealed that the specimens stabilised with geopolymer presented higher strengths, finding strengths approximately 24 times higher than the pure soil and 1.6 times higher than the soil stabilised with 8% cement. Adding waste glass powder and geopolymer allowed some blends to become suitable for use as a subbase in pavement applications. Microstructure analyses confirmed the formation of geopolymer through a more homogeneous structure. Finally, it was concluded that stabilising with geopolymer based on waste glass powder is an ecological and effective technique for increasing soil strength.

A Comprehensive Review of Opportunities of Nanomaterials in Stabilization and Construction Industry

Nanomaterials can be defined as materials possessing, at minimum, one external dimension measuring 1-100nm. Nanomaterials can occur naturally, be created as the by-products of combustion reactions, or be produced purposefully through engineering to perform a specialized function. These materials can have different physical and chemical properties to their bulkform counterparts. Considering these particle sizes, a new approach is proposed to use the nanoparticles in the geotechnical engineering to understand the nature of soil as nanoparticles will interact with soil particles more efficiently due to the advantage of their size i.e. 1nm to 100nm. As the new construction sites has been significantly increased in the area of poorquality ground several new approaches of stabilizing the soil underneath are introduced and one of these techniques are using the nanoparticles to improve the index properties of soil as well as strength of soil so that desired stability can be achieved. Different types of nanomaterials which can be used for the purpose of stabilization of soil are SiO¬2, TiO2, Al2O3. This paper also addresses the use of nanomaterials in housing construction, comparing their influence at the technical-structural level. Materials such as titanium dioxide, carbon nanotubes, nano silica, nanocellulose, nano alumina, and nano clays were analyzed. It was obtained that these nanomaterials can improve the structural, thermal, and functional properties of construction materials. In addition, they are related to increased durability, increased mechanical strength (>20 %), reduced thermal conductivity, and self-cleaning capability. Therefore, the use of nanomaterials promises to improve the sustainability and efficiency of housing construction

THE EFFECT OF QUICKLIME ON THE CBR VALUE OF SOFT SOIL STABILIZED WITH NICKEL SLAG AND ALUMUNIUM HYDROXIDE

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

Study on the Influencing Factors of Shear Strength of Carbonate Saline Soil based on Ring Shear Test

The Songnen Plain, situated in the northeastern region of China, is a typical seasonal permafrost zone with extensive carbonate saline soil. Physical parameters and environmental conditions are important factors influencing the mechanical properties of shallow carbonate saline soil. In this study, the effects of dry density (1.35g/cm3, 1.40g/cm3, 1.45g/cm3, 1.50g/cm3), salt content (0.5%, 1.0%, 1.5%), and freeze-thaw cycles (0, 1, 3, 5, 10, 15) on the shear strength of carbonate saline soil were systematically investigated through ring shear tests. The test results conclusively demonstrate that the shear strength of carbonate saline soils exhibits a positive correlation with the dry density. When the dry density increases from 1.35g/cm3 to 1.50g/cm3, the increase range of the shear strength of samples is between 5.0% and 11.3%. The impact on the shear strength of carbonate saline soils is relatively insignificant when the salt content changes in the range of 0.5% to 1.5%, with the shear strength of the soil fluctuating within the range of 1.8% to 3.2%. The freeze-thaw cycles lead to a progressive decay in the shear strength of carbonate saline soils, and the shear strength of the soils attains a relatively stable state after 5 freeze-thaw cycles. After 15 freeze-thaw cycles, the shear strength of carbonate saline soil diminishes by 15.2%. This study can provide scientific references for slope stability analysis and landslide control in regions with carbonate saline soil distribution.

Study of soil strength variation patterns under temperature changes using piezoelectric testing technology

Study of soil strength variation patterns under temperature changes using piezoelectric testing technology

The response characteristics and stability evaluation of vegetated slope under strong wind

As one of the major geological disasters in southeastern China, typhoon-induced vegetation slope instability causes significant loss of life and property each year. Despite the criticality of this issue, the response mechanism of vegetated slopes to wind loading in terms of soil deformation and stability still remains unclear. This research conducted field investigations on 330 historical landslides in Yongjia County, Zhejiang Province, analyzing their spatiotemporal distribution and developmental characteristics to establish a conceptual model. The influence of wind and vegetation conditions on slope dynamic parameters and soil strength parameters were subsequently determined through numerical simulations using FLAC3D software, model tests, and direct shear tests. The results show that: (1) The influence of wind on the dynamic response of vegetated slopes is significantly affected by wind speed. At wind forces ≤ 12 (hurricane: 32.7–36.9 m/s), vegetation plays a positive role in enhancing slope stability. At wind forces ≥ 13 (typhoon: 37.0–41.4 m/s), vegetation exerts a negative influence under the combined action of strong wind loads. (2) Based on the experimentally determined evolution of soil strength parameters, a formula c (v, w) was fitted to express the variation of cohesion with wind speed (v) and moisture content (w). (3) The optimized evaluation model demonstrates increased sensitivity compared to the traditional model, resulting in a 17.88% increase in sliding force and a 10.62–11.64% increase in anti-sliding force. This research accounts for both the direct and indirect effects of wind loading on vegetated slopes. The findings are expected to enhance the stability assessment of vegetated slopes under strong winds and facilitate the development of more accurate machine learning and statistical models in the future.

Comparison of the efficacy of carbonation and conventional curing for remediation of copper-contaminated soils by ladle slag

Soil contamination poses an increasing challenge for global sustainable development. Traditional remediation methods, such as using ordinary Portland cement (OPC) for treating contaminated soils, are limited by high CO2 emissions, significant energy consumption, and natural resource depletion. A sustainable approach utilizing steel production waste (ladle slag, LS) to efficiently remediate copper (Cu)-contaminated soils was proposed in this study. The efficacy of this remediation using carbonation and conventional curing methods was compared. Cu-contaminated soils, spiked with varying initial concentrations, were treated with 10 % LS and subjected to both conventional and carbonation curing for different durations. Leaching behavior, strength development, and chemical and mineral properties of LS-remediated Cu-contaminated soils were assessed. The results demonstrated that both CO2 and conventional curing significantly reduced Cu leaching in contaminated soils by 4–5 orders of magnitude compared to untreated soils. CO2 curing achieved these reductions in a shorter time (56–72 hours) than conventional curing (28–56 days). Additionally, CO2 curing sequestered up to 8 % CO2 in the soils. However, higher Cu concentrations hindered carbonation reactions, lowering CO2 sequestration. While CO2 curing improved soil strength, increased initial Cu concentration diminished this effect. During CO2 curing, the formation of Ca- and Mg-carbonates contributed to microstructural densification and binding, thereby improving strength. These carbonates also encapsulated Cu, preventing its leaching. In contrast, the addition of Cu enhanced hydration reactions and improved the strength development of Cu-contaminated soils subjected to conventional curing. Conventional curing produced calcium aluminum silicate hydrate, which effectively bound soil particles, filled pores, and encapsulated Cu, reducing its leaching.