Cement Stabilization Research Articles

A Microstructural Insight into the Hygrothermal Behaviour of Unstabilised and Cement Stabilised Compressed Earthen Bricks Exposed to High Temperatures

Earthen materials has received a lot of attention as a sustainable building material over the past few decades because of its eco-friendliness. As consequence of this renewed interest, numerous works have been recently developed on earthen materials, mostly with a focus on their mechanical behaviour. Conversely, there is still a significant gap in the literature on the understanding of the fire behaviour of earthen materials. Only a handful of studies has dealt with this subject and a systematic analysis on the causes of thermal instabilities in earth materials at high temperatures is still missing from the literature. The role played by the mineralogy of the earth materials on these thermal instabilities is still poorly understood and it requires further investigation. To fill these gaps, the present study presents the results from both mineralogical and hygrothermal tests performed on earth samples, which were either left unstabilised and compacted at 50 MPa or stabilised with cement and compacted at the optimum standard Proctor. Interestingly, unstabilised earthen samples exhibited thermal instabilities when exposed to high temperatures. To investigate deeper into the mineralogical causes of such thermal instabilities, samples were either equalised at the ambient temperature of about 25 °C or exposed at the high temperature of 350 °C before being subjected to thermogravimetric and differential scanning calorimetry (TG-DSC) tests, Fourier Transform Infrared (FTIR) spectroscopy tests, isothermal adsorption-desorption tests, and nitrogen gas permeability tests. Results show that cement stabilisation induced the formation of fresh the calcium-silicate-hydrate (C-S-H) and calcium-aluminate-hydrate (C-A-H) gels while reducing the water adsorption capacity. Both effects have rendered the material less prone to thermal instabilities compared to the unstabilised material. The main mineralogical and moisture-related changes influencing thermal and fire behavior might not be well captured by traditional studies. Though lacking in information to perform a thorough study, they do provide initial indications of possible internal alterations within the materials.

In silico screening and immunogenic features of putative tick cement protein PA107 from Ixodes ricinus tick.

Tick salivary proteins are crucial for efficient and successful tick feeding. Most of them are still uncharacterized, especially those involved in the formation of tick cement. Tick salivary protein PA107 is a putative cement protein, which is transcribed in salivary glands during the initial phase of tick feeding. It is a tick-unique protein, with homologs described in several tick genera. In this study, a detailed in silico analysis of its primary and tertiary structure was performed, along with the immunogenicity assessment for the PA107 protein from Ixodes ricinus species. The screening of the primary structure placed it to the glycine-rich protein family, revealing in parallel an overlapping 15mer at the C-terminus and borderline homology to non-tick proteins with antimicrobial activity. The analysis of tertiary structure revealed a high degree of intrinsic disorder for monomeric PA107, in contrast to highly ordered structures for different oligomeric states that might correlate with the putative role in the tick cement formation process. Regarding in silico PA107 immunogenicity inference, obtained results were inconclusive, which aligns with the in vitro findings showing definitely the lack of humoral response induction in experimentally infested rats and persons bitten by the I. ricinus ticks. The results represent new pieces of a huge puzzle depicting a complex tick-host relationship, but also identify PA107 as a possible compound of novel formulations to be used in biomedicine as bioadhesives, and as a target for new anti-tick strategies, by interfering with the cement cone formation and stability, i.e. tick attachment and feeding.

Strength Tests and Mechanism of Composite Stabilized Lightweight Soil Using Dredged Sludge.

To achieve resourceful utilization of dredged sludge, lightweight treatment was performed on sludge from Xunsi River in Wuhan using fly ash, cement, and expanded polystyrene (EPS) particles. Density tests and unconfined compressive strength (UCS) tests were conducted on the composite stabilized sludge lightweight soil to determine the optimal mix ratio for high-quality roadbed fill material with low self-weight and high strength. Subsequently, microstructural tests, including X-ray diffraction (XRD) and scanning electron microscopy (SEM), were conducted. The Particle (Pore) and Crack Analysis System (PCAS) was used to analyze the SEM images, investigating the cement-fly ash composite stabilization mechanism. The experimental results showed that the optimal lightweight treatment was achieved with an EPS content of 80% (by volume ratio to dry soil), cement content of 7.5% (by mass ratio to dry soil), and fly ash content of 5% (by mass ratio to dry soil). The density of the optimized lightweight soil was 1.04 g/cm3, a reduction of 28.27% compared to the density of raw sludge soil (1.45 g/cm3). The UCS increased significantly from 110 kPa for raw sludge soil to 551 kPa. The addition of fly ash enhanced the hydration and secondary hydration reactions between cement and sludge, generating more calcium silicate hydrate (C-S-H) gel, which filled the larger pores between the EPS particles and soil particles, as well as those between the soil particles themselves, making the structure denser. Compared to single cement stabilization, composite stabilization resulted in a lower content of expansive ettringite crystals, a more uniform pore distribution, fewer pores, and a lower surface porosity ratio. These research findings can provide theoretical support and practical references for the lightweight treatment of dredged sludge in the Yangtze River Basin of Central China.

Design and Construction of Concrete Pavement On Interstate 66 in Fairfax County, Virginia Applications of New Technologies

The article details the implementation of innovative technologies in the design and construction of a 10.3-kilometer concrete pavement on Interstate 66 in Fairfax County, Virginia, as part of a $140 million reconstruction project. Key technologies employed include cement stabilization of subgrade soils, use of a stabilized open-graded drainage layer, recycling of the original concrete pavement, and the introduction of fast-track concrete paving techniques. The project faced challenges due to deteriorating conditions of the original pavement, constructed in the early 1960s, under increasing traffic volumes. A comprehensive study involving traffic analysis, soil surveys, and structural assessments informed the decision to replace the existing pavement entirely with a new structure designed for improved drainage and durability. Construction strategies prioritized minimizing traffic disruption and maximizing the use of recycled materials. The successful completion of the project on schedule, despite additional work and unforeseen conditions, illustrates the viability of rapid concrete pavement construction using advanced technologies and materials. (Abstract generated by AI tool ChatGPT 4)

Mechanical Properties of Cement-Stabilized Sandy Soils Modified with Consoil

This study investigates the mechanical enhancement of sandy soils through cement stabilization modified with Consoil, targeting improved pavement substructure performance. Unconfined compressive strength (UCS) tests were conducted on samples with varying cement contents (3%, 6%, 9%), Consoil dosages (0%, 5%, 10%, 15%, 20% by cement weight), and curing periods (3, 7, 28, 90 days). Field Emission Scanning Electron Microscopy and X-Ray Diffraction analyses complemented mechanical testing to understand strengthening mechanisms. Results demonstrated that 15% Consoil consistently optimized strength development across all cement contents, with 9% cement and 15% Consoil achieving peak 90-day UCS of 17.74 MPa, representing a 67% increase over control samples. Microstructural analysis revealed progressive matrix refinement with increasing Consoil content, while XRD indicated enhanced pozzolanic activity through calcium hydroxide consumption. The study introduces Consoil as an effective stabilization additive, establishing optimal dosage rates and demonstrating significant strength improvements through synergistic cement-Consoil interactions. The findings provide new insights into strength enhancement mechanisms in Consoil-modified cement-stabilized soils, offering practical guidelines for designing high-performance pavement substructures. The research contributes to sustainable construction practices by optimizing cement usage through Consoil incorporation. Doi: 10.28991/CEJ-2025-011-01-011 Full Text: PDF

Enhancing Compressed Earth Block Performance: Effects of Gelatinized Starch and Fiber Reinforcement on Mechanical Properties

This study investigates the impact of starch stabilization and fiber reinforcement on the mechanical properties of Compressed Earth Blocks (CEBs). Various stabilization methods were tested to enhance the mechanical performance of CEBs, with a focus on starch as a natural binder and the incorporation of hemp as natural fibers. The research findings indicate that while starch slightly reduced internal cohesion by 13%, the addition of fibers alone significantly improved compression resistance by increasing strength by a factor of 3.57. When combined with starch, the effectiveness of fibers on compression resistance slightly decreased to a factor of 3.21. Cement stabilization, though providing the highest strength with a factor of 7, poses greater environmental challenges due to its high energy consumption and carbon emissions. In contrast, starch and natural fibers offer promising, eco-friendly alternatives that enhance CEB performance while reducing environmental impact. This study highlights the potential for integrating sustainable materials into construction practices to meet both structural and environmental objectives.

A review on treatment gypsum soil by using cement and lime

Gypsum soils, known for their high solubility and weak structural integrity, pose significant challenges in construction and agricultural applications. These soils tend to exhibit excessive settlement and reduced load-bearing capacity, particularly when exposed to moisture. Lime and cement stabilization has emerged as a promising solution to mitigate these challenges. By improving the soil mechanical properties through chemical reactions, Soil stabilization improves durability and strength, making it suitable for various engineering purposes. This paper reviews recent advancements, challenges, and opportunities associated with the application of lime and cement to gypsum soils, focusing on geotechnical performance and practical implications.

IMPROVING MECHANICAL PROPERTIES OF COMPRESSED EARTH BLOCKS THROUGH WET GRANULAR CORRECTION

This study explores methods to improve the mechanical properties of compressed earth blocks (CEBs) focusing on wet granular correction. We investigated how wet and dry granular corrections influence the compressive strength of CEBs. The results were compared to those obtained through cement stabilization. The results show that wet granular correction significantly improves the compressive strength of CEBs compared to dry correction, reaching a strength equivalent to the one obtained with 4.8% cement content. This method is therefore promising for optimizing the performance of CEBs while reducing cement use, in line with a sustainable and environmentally friendly approach. Further research is recommended to evaluate the effectiveness of this method on other types of soils with alternative binders to cement.

Mechanical and physical properties of stabilized compressed earth block (CEB) reinforced with date palm wood chips

In the building sector, compressed earth blocks (CEB) are valued for their affordability, environmental friendliness, and energy efficiency. This study investigates the mechanical and physical properties of CEBs reinforced with date palm wood chips (DPWC) in variable amounts (0%, 0.1%, 0.3%, and 0.5%) and stabilized with different stabilizers (5% and 10% cement, 7% and 12% lime). The mixtures were then compacted under a static load. The mechanical properties were evaluated through compressive strength tests conducted under both wet and dry conditions at 28 days. In addition to assessing the mechanical performance of CEB over the long term, flexural and compressive strength tests were performed on CEB samples after 60 days. The findings show that adding (DPWC) improves the flexural strength in particular cement stabilization ratios, while adversely affecting the compressive strength of CEB. The study highlights the need for careful fiber content management, as excessive fibers can weaken CEB, particularly when lime is used as a stabilizer. Furthermore, Cement-stabilized CEBs continue to improve in strength over time, while lime-stabilized samples show less significant improvements.

The effectiveness of fly ash and fly ash-cement mixtures as stabilizing materials for high plasticity clay

Abstract The increasing activity of burning coal as fuel for Steam Power Plants (PLTU) will increase the amount of fly ash waste, urging the industry to maximize waste utilizations as, for instance, a stabilizing material for high plasticity clay. This research examined the effectiveness of clay + fly ash and clay + fly ash + cement stabilization in increasing the strength of road subgrade. The results showed that fly ash and fly ash + cement improved clay properties, demonstrated by the value of unsoaked CBR (5.78%) and soaked CBR (3.11%) of unstabilized clay. Clay + 20% fly ash yielded optimum CBR value (23,13%), and stabilizing clay subgrade on a 50-meter section using 20% fly ash at a cost of IDR 18,329,675. The mix of 40% fly ash + 15% cement yielded optimal CBR value (42.70%) at a cost of IDR 18,359,435.00. The evaluation of soil properties and cost analysis, shows that the most efficient mixture variation is 40% fly ash and 15% cement for clay stabilization.

Impact of Different Time Intervals on the Color Stability of Glass Ionomer Cement and Composite Materials Bonded to Silver Diamine Fluoride: An In Vitro Study.

Objective This in vitro study evaluated the impact of different time intervals on the color stability of glass ionomer cement (GIC) and composite materials bonded to teeth treated with silver diamine fluoride (SDF). Specifically, the study sought to determine if immediate or delayed application of these restorative materials affects the degree of staining caused by SDF. Materials and methods Twenty-eight extracted primary molars with cavitated lesions were randomly divided into four groups, each comprising seven samples. SDF was applied to all samples, followed by either immediate or delayed restoration using GIC or composite materials. Group I received immediate composite restorations, Group II received immediate GIC restorations, Group III received composite restorations after a two-week delay, and Group IV received GIC restorations after a two-week delay. Color measurements were taken at various time points using a digital spectrophotometer, and the color difference (ΔE value) was calculated using the CIELAB color space system. Results Composite restorations exhibited better color stability than GIC. Immediate restorations had higher discoloration (ΔE: composite 4.25, GIC 26.95). Delaying restorations by two weeks reduced discoloration (composite 1.66, GIC 10.66), with composites showing minimal color change. Conclusion Composite restorations exhibited superior color stability compared to GIC, and delayed restoration reduced SDF-induced staining more effectively than immediate restoration.

COMPARISON OF THE EFFECTS OF STANDARD NOZZLES AND EXTENSION TUBES ON THE EROSION OF PMMA USING PULSATING WATER JET TECHNOLOGY

The study of bone cement disintegration is important for advancing orthopedic and trauma surgery outcomes. Bone cement, commonly used in joint replacement procedures, plays a vital role in fixation implants. However, the long-term stability and integrity of bone cement are critical for the success of these procedures. This study focuses on the use of ultrasonic pulsating water jet technology for the selective removal of bone cement, aiming to provide a precise and efficient method for revision surgeries. The disintegration efficiency is measured in terms of depth, width and volume of the disintegrated bone cement as a result of variations in the nozzle geometry, supply pressure and traverse speed. Two different nozzle types, the standard nozzle insert and nozzle with an extension tube of 100 mm having a diameter of 0.3 mm, are used. Two supply pressure levels were taken as 10 and 20 MPa with five levels of traverse speeds as 0.5, 1, 1.5, 2 and 2.5 mm/s. The results showed an increased disintegration efficiency for all experimental conditions using an extension tube nozzle as compared to a standard nozzle (20 – 25% in terms of disintegration volume). Also, the disintegration efficiency increased with higher pressure level values (8.2 mm3 and 4.85 mm3 for p = 20 and 10 MPa, respectively) and lower traverse speed values. The results showed a promising direction in terms of the utilization of an ultrasonic pulsating jet with a modified nozzle type for higher bone cement disintegration efficiency.

Study on the Factors Influencing the Adsorption Mechanism of CSH Gel for Chloride Ions.

Calcium silicate hydrate (CSH) gel is an important hydration product of cement, significantly influencing the coagulation and hardening processes, as well as the mechanical properties, volume stability, and durability of cement. Moreover, it plays a crucial role in the adsorption of harmful ions. In this study, CSH gel was synthesized through the precipitation of calcium acetate and sodium silicate and was subsequently used to adsorb chloride ions. The results indicated that when the calcium-to-silicon ratio was 1.2, the CSH gel exhibited excellent adsorption performance for chloride ions introduced via CaCl2 and NaCl, with adsorption capacities of 17.45 mg·g-1 and 8.06 mg·g-1, respectively. The adsorption of chloride ions in CSH gel primarily occurs due to the physical adsorption of chloride ions on the surface and within the internal pores of the CSH gel, accompanied by a displacement reaction between hydroxide ion and chloride ions.

A biomechanical investigation comparing a novel bone cement bridging screw system with conventional treatment methods for Kummell’s disease

Based on the characteristics of Kummell’s disease (KD) and related anatomical structures of the thoracolumbar spine, a novel bone cement screw system has been designed to effectively avoid the cement loosening and displacement. This experiment aimed to assess the biological effects of the novel bone cement screw system in KD on fresh cadaveric thoracolumbar spine specimens, thereby discussing its potential application value and providing a foundation for clinical implementation. This study employed a total of 50 fresh female adult cadaver specimens. Each specimen underwent extraction of the T12 to L2 segment followed by the creation of an artificial KD model at the L1 segment and subsequent establishment of five distinct types of bone cement repair models. Model A represents the percutaneous vertebroplasty (PVP) model, Model B combines PVP with unilateral percutaneous pediculoplasty (PPP), Model C combines PVP with bilateral PPP, Model D introduces the novel bone cement screw combined with unilateral PVP, and Model E combines the novel screw with bilateral PVP, each group consists of 10 specimens. Subsequently, the six-axis spine robot was employed to execute cement three-dimensional biomechanical strength tests in six directions, including anterior flexion and posterior extension, left and right lateral bending, as well as left and right rotation. The novel bone cement screw, whether used unilaterally or bilaterally in combination with the PVP model, exhibits significantly reduced bone cement mobility and superior biomechanical stability during anterior flexion, posterior extension, left lateral bending, and right lateral bending (P<0.05).No significant differences were observed among the five models under both left and right rotation (P > 0.05).When comparing the novel bone cement screw combined with PVP unilaterally and bilaterally, no statistically significant difference was observed in the stability of bone cement across all six directions of motion (P>0.05). To conclude, this novel bone cement bridging screw system exhibits superior biomechanical stability compared to commonly used treatments. Furthermore, both unilateral and bilateral implementations of the novel bone cement screw system yield without significant differences observed. These findings present a reliable and innovative approach for clinical management of KD.

Radiation stability and durability of magnesium phosphate cement for radioactive reactive metals encapsulation

The encapsulation of Radioactive Reactive Metallic Waste (RRMW) in ordinary Portland cement poses significant challenges due to its incompatibility with the alkaline environment of the matrix. To address this issue, magnesium phosphate cements (MPC) emerge as potential solutions for the safe and effective immobilisation of RRMWs. The radiation stability and durability of an optimised formulation have been examined for samples irradiated up to 1000 kGy, in particular concerning the leaching behaviour of the three main constituents of the cement hydration products, and on four artificially added elements used to simulate radionuclides commonly found in radioactive waste (caesium, strontium, europium, and cobalt). The mortars exhibited excellent leaching behaviour and a high mechanical resistance, even after irradiation, freeze-thaw cycles, and water immersion. No significant radiation-induced effects were observed in the mineralogical and microstructural properties of the mortars, thus supporting their stability at the examined doses. Having verified the compliance with the main Italian waste acceptance criteria, the results of this research represent an encouraging step for the future implementation of MPCs for RRMWs conditioning.

Influence of acid systems on bottomhole zone decolmatization and set cement stability

Influence of acid systems on bottomhole zone decolmatization and set cement stability

Innovations in recycled construction materials: paving the way towards sustainable road infrastructure

The expansive development of infrastructure has led to increased consumption of virgin aggregates in road construction, resulting in significant environmental impacts. To address this issue, there is a pressing need for sustainable alternatives that utilize recycled materials in pavement applications. This paper presents a comprehensive review of a decade-long research program focused on the development and evaluation of sustainable pavement materials, such as recycled and waste aggregates, industrial by-products, and natural fibers. The research encompassed a wide range of innovative materials and technologies, such as geopolymer-stabilized recycled aggregates, cement-stabilized waste materials, natural additive-modified cement stabilization, and recycled aggregate-geogrid reinforcement systems. The experimental framework employed a combination of mechanical testing, durability assessment, microstructural analysis, and environmental safety evaluation to assess the performance and sustainability of these materials. The key findings demonstrated the superior mechanical properties, improved durability, and environmental suitability of the recycled materials compared to conventional virgin aggregates. The successful implementation of these sustainable solutions in real-world projects highlights their potential to reduce the environmental footprint of road infrastructure development. Furthermore, the paper discussed the practical implications of the research outcomes for pavement design and construction, as well as future research directions to further advance the field of sustainable pavement engineering. The findings of this research report can be used as guidance for researchers, practitioners, and policymakers seeking to upcycle the widespread adoption of recycled materials in road application and contribute to the development of a more sustainable and resilient transportation infrastructure.

Compressive Strength Characteristics of Compressed Stabilized Earth Block (CSEB) Units and Walls

This paper is mainly focused on compressive strength behavior of Compressed Stabilized Earth Block (CSEB) units and CSEB walls. Compressed Stabilized Earth Block (CSEB) is a rectangular block used in wall construction. The ingredients of CSEB are soil, cement, fine aggregate, crusher dust, and a small amount of water. These blocks have less energy consumption and carbon emission, and they provide improved thermal insulation. In addition, they use local resources and disseminate appealing aesthetics with elegant profile and uniform size. Due to these advantages CSEB can be used as a green construction material. This research aims to study the strength characteristics of CSEB wall in compression and evaluate the suitability of CSEB walls as load bearing walls in structures. This research studies physical and mechanical characteristics of CSEB units made from red residual soil of Lele (Lalitpur) with 8% cement for stabilization. This paper discusses the compressive strength behavior of walls constructed of size 0.660m x 1.100m x 0.220m using CSEB units in cement sand mortar and stabilized mud mortar separately which were tested after 28 days. The experimental values after laboratory testing of CSEB masonry wall with height to thickness ratio 5:1 for cement sand mortar (1:6) and stabilized mud mortar (stabilized with 8% cement and 16% extra sand) separately are compared with relevant values from different codes. Results obtained from compressive strength tests of masonry walls constructed in the laboratory and those values from different codes concerning the strength of masonry unit and mortar are compared and found to be in agreement. The comparison of laboratory results with codal provisions of design of masonry walls illustrate that CSEB masonry walls can be designed in the similar way as brick masonry walls.

The Effects of Metakaolin on the Properties of Magnesium Sulphoaluminate Cement.

Magnesium sulphoaluminate (MSA) cement has good bonding properties and is suitable as an inorganic adhesive for repairing materials in civil engineering. However, there are still some problems with its use, such as its insufficient 1 day (d) strength and poor volumetric stability. This paper aims to investigate the influences of metakaolin (MK) on the physical and mechanical properties of magnesium sulphoaluminate (MSA) cement. The hydration products and microstructures of typical MSA cement samples were also analysed using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). The results showed that the addition of metakaolin reduces the fluidity and shortens the setting time of the MSA cement. The initial setting time and final setting time shortened maximally by 15-27 min and 25-48 min, respectively, with the addition of 10-30% metakaolin. Moreover, the compressive strength and flexural strength of the MSA cement improved significantly with the addition of 10-30% metakaolin at a curing age of 1 d. Compared with the compressive and flexural strengths of the control sample at 1 d, the compressive strengths of the modified samples showed obvious increases of 98%, 101%, and 109%, and the flexural strengths increased by 39%, 31%, and 26%, respectively, although they decreased slightly when the curing ages were 7 d, 14 d, and 28 d. The addition of 10% metakaolin improved the water resistance of the MSA cement immersed in water for 7 d and resulted in even higher water resistance at 28 d. The addition of 10-30% metakaolin improved the volumetric stability of the MSA cement with increasing dosages before 28 d of ageing. XRD and SEM-EDS analyses showed that the metakaolin accelerated the early hydration reaction and optimised the phase composition of the MSA cement. The results indicate that the addition of 10-20% metakaolin improved the strength after 1 d of ageing, water resistance, and volumetric stability of the MSA cement, providing theoretical support for the application of MAS cement as an inorganic bonding agent for repairing materials.

Investigation of the thermomechanical characteristics of compressed earth bricks reinforced with cement and corn straw waste fibers

The earthen construction sector attracts worldwide attention, and earthen bricks are widely used. The construction industry has also progressed in its use of natural green resources such as plant fibers to design building materials that are both economically and ecologically sustainable. However, the valorization of plant waste in construction represents a crucial environmental challenge. The present study focuses on the development and characterization of a new, low-cost earth-based building material stabilized with cement and corn straw fibers in southeastern Morocco. Different earth bricks stabilized with different cement contents and corn straw fibers were developed. The physico-chemical characterization of the soils used in the design of the bricks was carried out, using physico-chemical, mineralogical and geotechnical characterization, including X-ray diffractometer (XRD) analysis, Fourier transform infrared (FTIR) spectra and energy dispersive X-ray (EDX) analysis. The first results reveal that the predominant minerals in oasis soils include ferrous clinochlore, muscovite, calcite and quartz, which are mainly composed of silt and sand. Then, the eligibility of these soils for compressed earth brick (CEB) construction was assessed, adhering to established guidelines for the identification of suitable soil types. In addition, the thermal properties of the bricks were determined, finding that the use of corn straw fibers improves the thermal performance of the bricks, and cement stabilization leads to an improvement in the bricks' mechanical properties.