Cement Technology Research Articles

Application of Mirror Image 3D-Printing Technology Bone Cement in Treatment of Stage IIIb Necrosis of the Lunate Bone.

At present, conventional operations are weak for pain relief and restoring the carpal joint function in the treatment of avascular necrosis of the lunate bone. Mirror image 3-dimensional (3D)-printing technology has rarely been reported for the treatment of lunate bone necrosis, The use of mirror 3D-printed lunar bone replacement and bone cement technology in the treatment of stage IIIb lunar bone necrosis has been rarely reported in previous literature. Personalized customized 3D-printed prostheses have become an effective solution for solving many complex cases, and the flexible application of bone cement technology can also achieve satisfactory clinical results. The authors report 3 patients who underwent mirror printing of lunar bone prostheses based on healthy side lunar bone computed tomography data, 3D printing of lunar bone prostheses replacement through small incisions, and intraoperative selection of alternative bone cement technology based on actual conditions. Mirror image 3D printing relieved the pain and resulted in satisfactory functional recovery for stage IIIb lunate bone necrosis.

Patterns of Changes in the Mechanical and Filtration Properties of Semi-Rock Soils Modified by Jet Cementation

When installing underground structures in soil layers with high groundwater filtration rates, special requirements are imposed on the material of anti-filtration curtains. The conditions of application of jet cementation technology for modification of watered fractured rocky soils of low strength in order to form a composite material with the required mechanical and filtration characteristics are considered.The technological parameters of the cementation process have been experimentally and theoretically determined to ensure the necessary radius of propagation of the bonding mixture, and methods of laboratory and field control of the modified zone have been developed. The maximum permissible values of the controlled parameters have been determined.

Prediction of characteristics of soil-concrete massifs created by injection of extremely finedispersed binders (microcements)

The urgency of the problem associated with the use of injection erection technology of soil cementation in various engineering and geological conditions is substantiated. Due to the peculiarities of cementation technologies under various modes of injection impregnation and the possibility of applying certain technical injection parameters for different types of soils, it is possible to improve various deformation characteristics of the soil mass when implementing the technology. Some results of the analysis of the work of injection cementation of soils in dispersed soils are presented and general patterns are established under which it is necessary to adjust the parameters of cementation. The theoretical prerequisites are considered in relation to experimental data, the effectiveness of the application of cementing technology in the injection impregnation mode is proved and the general applicability of the application of these cementing methods with an increase in the technical indicators of the fixed soils is established.

Key durability characteristics of GGBS-cement kiln dust based concretes

With the advent of global warming, the concrete industry has the potential to drive the future of construction through sustainable cement technologies. These technologies rely on activation of industrial waste materials, such as Cement Kiln Dust (CKD) and Ground Granulated Blast Furnace Slag (GGBS) while Portland cement (PC) content is maintained at a minimum, resulting in concrete products of reduced embodied carbon footprint. This work reports on the durability of mixes made from PC, GGBS and CKD at incremental contents of 40-75% and 0-35% for GGBS and CKSD, respectively, in an attempt to identify durable formulations while maintaining blends at low embodied CO2 emissions in the Sultanate of Oman. Dimensional changes, sulfate and chloride resistance, as well as surface resistivity were determined and compared to those of a PC-based concrete formulation. The results suggest that, when GGBS and CKD were incorporated within the mix at an optimum content of 55% and 20% respectively, the concretes appeared to have exhibited promising durability characteristics which could lead towards the material’s implementation within a greater context.

Evaluation of the Fatigue Performance of Full-Depth Reclamation with Portland Cement Material Based on the Weibull Distribution Model

The full-depth reclamation with Portland cement (FDR-PC) technology embodies an environmentally friendly approach to solving the damage to old asphalt pavement. Fatigue failure emerges as the predominant mode of degradation for FDR-PC pavement. The fatigue characteristics of the full-depth reclamation with Portland cement cold recycled mixtures were evaluated through four-point bending tests. Three contents (4%, 5%, 6%) of cement and three base-to-surface ratios (10:0, 8:2, 6:4) were utilized. The fatigue equations were derived for the mixtures using a two-parameter Weibull distribution. The results indicate that all correlation coefficients of the Weibull distribution model surpass 0.88, effectively projecting the lifespan of FDR-PC. With increases in cement contents and base-to-surface ratios, the fatigue life of the mixture extends, though with an augmentation of stress sensitivity. Comparative analysis with the fatigue equation model parameters of the current Chinese specifications for the design of highway asphalt pavement reveals that mixtures with a 4% cement content and combinations of a 5% cement content with a low base-to-surface ratio meet the requirements for inorganic-binder-stabilized soil. Additionally, mixtures with a 5% cement content and a high base-to-surface ratio, along with those with a 6% cement content, fulfill the specifications for inorganic-binder-stabilized granular materials.

Foamed Cement Applications in Oil Industry Based on Field Experience: A Comprehensive Review.

Foam cement is a versatile cementing material that has found numerous applications in the oil and gas industry. As research continues to advance and improve the properties of foam cement, it is likely that we will see an increased use of this material in the years to come. This review aims to summarize the current state of the art and the latest developments in the utilization of foam cement in oil fields. The study focuses on the key benefits of foam cement, including its light weight, excellent flow properties, ability to maintain its structural integrity over time, and high compressive strength. It also examines its various applications in oil field operations, such as cementing against fragile formations, well abandonment, zonal isolation, cementing offshore wells, and well remedial cementing. Furthermore, the paper evaluates the various factors that influence the performance of foam cement, such as the mixing design, foam structure, and stability. In addition, the methods for evaluating the foamed cementing job and the integrity of the formed cement sheath are also presented. The review also highlights the current challenges and limitations of foam cement technology that should be considered when using foamed cement in oil field applications and discusses the future directions for its development and optimization. This review provides a comprehensive overview of the applications of foam cement in oil fields and will be of great interest to engineers, researchers, and practitioners in the oil and gas industry.

Alkaline Activation of Binders: A Comparative Study.

Binders formulated with activated alkali materials to replace Portland cement, which has high polluting potential due to CO2 emissions in its manufacture, have increasingly been developed. The objective of this study is to evaluate the main properties of activated alkali materials (AAM) produced by blast furnace slag, fly ash, and metakaolin. Initially, binders were characterized by their chemical, mineralogical and granulometric composition. Later, specimens were produced, with molarity variation between 4.00 and 5.50, using the binders involved in the research. In preparing the activating solution, sodium hydroxide and silicate were used. The evaluated properties of AAM were consistency, viscosity, water absorption, density, compressive strength (7 days of cure), calorimetry, mineralogical analysis by X-ray diffraction, and morphological analysis by scanning electron microscopy. The results of evaluation in the fresh state demonstrate that metakaolin has the lowest workability indices of the studied AAM. The results observed in the hardened state indicate that the metakaolin activation process is optimized with normal cure and molarity of 4.0 and 4.5 mol/L, obtaining compressive strength results after 7 days of curing of approximately 30 MPa. The fly ash activation process is the least intense among the evaluated binders. This can be seen from the absence of phases formed in the XRD in the compositions containing fly ash as binder. Unlike blast furnace slag and metakaolin, the formation of sodalite, faujasite or tobermorite is not observed. Finally, the blast furnace slag displays more intense reactivity during thermal curing, obtaining compressive strength results after 7 days of curing of around 25 MPa. This is because the material's reaction kinetics are low but can be increased in an alkaline environment, and by the effect of temperature. From these results, it is concluded that each precursor has its own activation mechanism, observed by the techniques used in this research. From the results obtained in this study, it is expected that the alkaline activation process of the types of binders evaluated herein will become a viable alternative for replacing Portland cement, thus contributing to cement technology and other cementitious materials.

Projected traditions? Tracing an East German-Cuban Collaboration in Loam and Soil Cement Construction in Havana-Cocosolo

This article unveils the history of constructing the "Cocosolo Experimental House" in Havana, a collaborative endeavor involving East German and Cuban participants. This singular project was designed around 1989-90, in parallel with the end of the GDR, to serve as a prototype for “self-construction technology” making use of local soil. A crucial step in the development process of this project was the search for the most suitable construction material, ultimately leading to a choice between loam (a mixture of clay, silt, sand, and aggregates such as gravel, which does not require an additional binder) and soil cement (a mixture of local soil and cement, while cement works as binder). Although several obstacles prevented the project from being completed as planned, it was finished after the East German group from Weimar left within the framework of Cuba’s specific local self-construction system. The history of the Cocosolo project unfolds as a tapestry of experimentation, adaptation, and unintended consequences. It addresses both the socialist discourse regarding material scarcity—and the actual lack of construction materials in the Cuban context. In our article, based on archival research in Cuba and Germany as well as site surveys, we unpack the expectations of the German partners experimenting with loam abroad, as well as those of the Cuban actors, focusing on the local uses of soil cement technology. Finally, to nuance the understanding of how a Cuban loam-building tradition was imposed, we analyze the clash of expectations at the construction site.

Advancements in Cement Technology: A Comprehensive Review of Additives and Their Impact on Material Properties

Advancements in Cement Technology: A Comprehensive Review of Additives and Their Impact on Material Properties

Resource and energy saving technology of specialpurpose cements

AbstractBy obtaining and studying special‐purpose building materials based on the wastes of various industrial fields it has been found that that they exhibit a complex of predefined properties, and are both hydraulic and air binding materials. Physico‐mechanical properties of such materials vary over a wide range: water‐cement ratio – 0.12 – 0.25; initial set – from 50 minutes to 1 hour 50 minutes, final set – from 2 hours 15 minutes to 3 hours 25 minutes; compressive strength after 3 days of setting – 30 – 60 MPa, compressive strength after 28 days of setting – 50 – 85 MPa. In addition, experimental materials exhibit a complex of special properties: computed mass absorption ratio 200 – 280 cm‐1, sulfate resistance ratio after 6 months of setting in aggressive medium – 1.1 – 1.2. It is possible to obtain the following materials from chemical industry wastes: sand lime bricks (silicon‐containing wastes), heavy fillers for special purpose concretes (chromium wastes), various types of ceramics (calcium‐containing wastes), and in particular ferromagnetic ceramics (barium‐containing wastes).

A low carbon cement (LC3) as a sustainable material in high strength concrete: green concrete

Limestone Calcined Clay Cement (LC3) Technology is a low carbon cement that combines limestone, calcined clay, and clinker, aiming to reduce CO2 emissions by 40%-50% during production. In this study, large-scale investigations were conducted to explore LC3 as a potential substitute for conventional cement (CC). Mechanical and durability tests were performed on LC3, comparing results with CC and Pozzolana Cement (PC) concretes. The findings revealed that LC3 concrete exhibited promising early-stage strength similar to CC concrete. However, at 90 days, LC3 showcased a 10% higher strength compared to CC concrete. Additionally, LC3 displayed a remarkable 45% increase in resistance to moisture ingress, indicating improved durability over CC concrete. These results highlight the efficacy of low carbon cement in developing ternary blended cements that offer early strength and enhanced durability, making it a viable eco-friendly alternative in the construction industry.

Research and application of anti - corrosion cement slurry in formation water corrosion environment

Corrosion of cementing cement ring causes the cement ring permeability to increase, resulting in serious casing corrosion. The casing corrosion perforation leads to an increase in water content of oil wells, low driving use of water injection wells, and imbalance of injection and production well patterns. Therefore, on the basis of conventional cementing cement, epoxy resin emulsion non-penetrating agent and corrosion inhibitor composed of rust and antibacterial materials are added to reduce the corrosion and permeability of cementing cement and reduce casing corrosion. The cement sample permeability experiment shows that adding 10% non-permeability agent and 2% corrosion inhibitor to low-density cement reduces the cement stone sample permeability from 0.075mD to 0.021mD, a decrease of 3.57 times. In the conventional density cement, adding 10% non-penetrating agent and 2% corrosion inhibitor, the permeability of the cement stone sample decreased from 0.041mD to 0.0009mD, a decrease of 4.56 times. The evaluation experiment of cement stone anti-corrosion performance shows that adding 10% non-penetrating agent and 2% corrosion inhibitor to cement can increase the corrosion resistance of cement samples by 6 times. At the same time, the thickening time and compressive strength of cement stone samples remain unchanged compared with conventional cement. Optimizing the technological measures of supporting anti-corrosion tools, and summing up a set of anti-corrosion cementing technology through the field application of anti-corrosion cement slurry, which provides strong technical support for the development of cementing technology under the corrosive environment of formation water in the oil field.

Study on Bionic Self-healing Cement Slurry System

Aiming at the technical problem of gas channing in annulus caused by long-term sealing performance failure of cementing cement ring, based on the technical idea of “prevent before plugging” and from the perspective of chemical bionics, a kind of bionic self-healing cement slurry system of dissolving viscosity was developed. The indoor evaluation results show that the cement stone has excellent physical properties. When the compressive strength is reduced by 15%, the elastic modulus of the cement stone is reduced by 41%, showing good toughness and playing the role of “first prevention”. When the damaged cement stone is excited by hydrocarbon, a kind of soluble gel ester can be formed, and the cement stone skeleton can be re-bonded. Under the condition of methane curing, the recovery rate of compressive strength is 99%, the recovery rate of flexure strength is 58.2%, the recovery rate of gas permeability is 96.4%, and the recovery rate of liquid permeability is 100%, playing the role of “post-plugging”. Therefore, it is concluded that the adhesive dissolving bionic self-healing cement technology can effectively realize the late integrity and realize the long-term sealing integrity after the cement ring is broken through self-healing, which provides a powerful technical support for preventing the abnormal annulus pressure, a hidden danger of oil and gas well production safety.

СПОСОБЫ СИНТЕЗА СИЛИКАТСОДЕРЖАЩЕГО КЛИНКЕРА СТОМАТОЛОГИЧЕСКОГО ЦЕМЕНТА

The article provides an overview of modern cements used in dentistry with an emphasis on silicate cements such as mineral trioxide aggregate (MTA). The basic requirements for dental cements are given, including their safety, adhesion to tooth tissues, resistance to various influences and thermal properties. 
 The article analyzes in detail the composition and properties of industrial white Portland cement used in construction, in comparison with the characteristics of dental silicate cements. The general issues of the synthesis of high-base calcium silicates used in dentistry are considered from the standpoint of the chemical technology of Portland cement. The mineralogical composition and hydration processes of various cement components, their effect on tooth color and other properties are discussed. 
 The methods of reducing the temperature and increasing the rate of formation of calcium silicates, common in the technology of dental cements and in the production of Portland cement, are indicated. It is assumed that it is possible to accelerate solid-phase synthesis in the range of 1250-1350 °C with a special method of introducing mineralizers proposed at the V.G. Shukhov BSTU for the synthesis of white Portland cement, provided it is adapted for dental formulations.

Enhancing the Fresh and Early Age Performances of Portland Cement Pastes via Sol-Gel Silica Coating of Metal Oxides (Bi2O3 and Gd2O3)

Incorporating metal oxide nanoparticles into cement-based composites delays the hydration process and strength gain of cementitious composites. This study presents an approach toward improving the performance of bismuth oxide (Bi2O3) and gadolinium oxide (Gd2O3) particles in cementitious systems by synthesizing core–shell structures via a sol-gel process. Two types of silica coatings on cementitious pastes with 5% and 10% substitution levels were proposed. The rheology, hydration, and mechanical properties of the pastes were analyzed to determine the relationship between the coating type and nanoparticle concentration. The results indicate that despite the significant disparities in the performance of the resulting material, both methods are appropriate for cement technology applications. Bi2O3’s silica coatings accelerate the hydration process, leading to early strength development in the cement paste. However, due to the coarse particle size of Gd2O3, silica coatings exhibited negligible effects on the early age characteristics of cement pastes.

Meeting industrial decarbonization goals: a case study of and roadmap to a net-zero emissions cement industry in California

Recent decarbonization policies are expected to significantly impact high greenhouse gas (GHG) emitting industries, as they will be forced to find ways to operate with a lower environmental footprint. Due to the energy required for the kilns and the unavoidable chemical-derived emissions during manufacturing, in addition to its high global consumption levels, the cement industry is anticipated to be among the early industries affected. California State Bill (SB 596) is one of the first rigorous legislative measures that sets GHG emissions from cement production to net-zero by 2045. As such, a case study on California cement production is evaluated here. While several groups have developed cement technology roadmaps with GHG mitigation strategies, these roadmaps do not consider concomitant environmental impacts, such as those that can influence local populations, thus limiting potential implementation from a policy perspective. Here, we examine several GHG emissions mitigation strategies for cement production and show the greatest reduction from an individual measure is from implementing carbon capture storage for cement kiln flue gas (87%), use of alternative clinkers (78%), or use of alkali-activated materials (88%). Yet even if GHG emissions are reduced, use of high-polluting energy sources could increase risks to human health impacts. Further, the efficacy of these decarbonization measures is lowered if multiple measures are implemented simultaneously. Finally, we examine the potential to meet net-zero emissions, focusing on California production due to recent legislation, and find a pathway to 96% GHG emissions reduction. Notably, these reductions do not reach goals to hit zero emissions, suggesting direct air capture mechanisms will need to be implemented.

H2S-responsive zwitterionic hydrogel as a self–healing agent for plugging microcracks in oil-well cement

During cementing construction, H2S gas leak from micro-cracks of cement ring or cementing interface, seriously damaging wellbore integrity and shortening the life of wells. Therefore, microcrack self-healing cement technology is of great significance for oil wells to maintain the durability of cement rings and adapt to complex underground environments. Herein, acrylamide (AM), acrylonitrile (AN) and N-vinylformamide (NVF) were used as functional monomers, and laponite was added to prepare Laponite-poly(acrylamide-acrylonitrile-n-vinylformamide) nanocomposite hydrogel (L-PMAN) with excellent mechanical strength as micro-crack repair agent for gas-triggered cementing cement sheath. Considering the difference of chemical environment in the process of wellbore cement slurry sealing and subsequent micro-fracture plugging, different structural units were selected to design amphoteric structure. The construction of zwitterionic structure makes it exhibit excellent swelling behavior in salt solution while maintaining 80% of the original mechanical strength. More importantly, after adding L-PMAN powder,cement stone (C1) can achieve good repair of microcracks under the trigger of H2S within 3 days, and the maximum gas breakthrough pressure can reach 2.5 MPa, indicating the great potentials of the L-PMAN for plugging microcracks in cement sheath.

Новые данные о технологии изготовления кузнечной продукции сельских поселений Золотой Орды по результатам металлографических анализов изделий с селищ Багаевское и Широкий Буерак

The article introduces into scientific circulation the results of metallographic studies of the technology of blacksmithing products originating from excavations and casual finds from Bagaevka and Shiroky Buerak, the Golden Horde settlements of the Lower Volga region. In historiography, there is a shortage of studies of iron processing technology of the Golden Horde population from the Lower and Middle Volga regions. This article is intended to partially fill the existing research gap based on the results of archaeo-metallographic studies conducted in the archaeological laboratory of the Ulyanovsk State Pedagogical University. In the study, the authors use the archaeo-metallography method, developed by B.A. Kolchin, and currently widely applied in Russian archaeological science. As a result, it was established that simple bloom iron, raw irregularly carburized steel and specially prepared high-carbon steel were the main raw materials for blacksmithing products of the Bagaevka and Shiroky Buerak settlements. In the arsenal of forging products of the Bagaevka settlement, 86.8% of technological operations belong to group I (simple technologies without the use of a structural joint by forging welding of bloom iron and high-carbon steel, without copper soldering) and 13.2% belong to group II (wares with a structural joint by forging welding of bloom iron and steel with copper soldering). 58% of the metallographically studied wares were made of bloom iron and raw irregularly carburized steel. 29% of the items were forged technologically in order to obtain high-quality products. 15.8% of the products were made of all-steel work pieces, 10.5% produced from package work pieces. Cementation technology was recorded in 2.6% of the items. End welding and forging from two-lane iron-steel work pieces, which amounted to 5.3% each, were identified in the technological schemes related to the technological group II. In general, the revealed technological features of the blacksmith products of the Bagaevka collection are characteristic of the iron processing in the Middle Volga region in the Golden Horde period.

Effect of Bamboo Leaf Ash on The Properties of Geopolymer Concrete at Ambient Curing Temperature

As a result of the growing environmental concerns in the cement industry and the rising cost of building materials, alternative cement technologies have become an area of increasing interest. In this study, geopolymer concrete containing fly ash class F and bamboo leaf ash was chosen as a cement substitute in concrete manufacturing. This research was an experimental study evaluating the effect of bamboo leaf ash (BLA) on geopolymer concrete by addition as a partial replacement of fly ash. The test samples were 100 x 100 x 100 mm cubes and 300 x 150 mm cylinders at the ambient curing temperature. The design mix of C25 was used for this study. This research aimed to explore the suitability of the use of bamboo leaf ash as a mixing material in geopolymer concrete in more environmentally friendly industries. The properties that were investigated in this study are the basic aggregate tests, XRF analyses of BLA and fly ash, and workability tests by evaluating slump and compaction factor tests. In addition, compressive strength and splitting tensile strength of 28, 56, and 90 days. Therefore, in this study, various levels of bamboo leaf ash were utilized, including 0%, 5%, 10%, 15%, and 20% BLA. The alkaline liquid-to-binder ratio for all mixes was constant at 0.6, while the Na2SiO3 to NaOH ratio was 2.5. The test results of the workability show that the increased amount of bamboo leaf ash gradually reduces the alkaline liquid. The result of compressive and splitting tensile showed that fly ash substitutes that contained 5% and 10% of the bamboo leaf had higher strengths of about 38.7 MPa, 40.8 MPa, 4 MPa, and 4.22 MPa, respectively than other mixtures. Therefore, bamboo leaf ash can be one of the constituent materials used to improve the mechanical properties of geopolymer concrete

Solidification/Stabilization Technology for Radioactive Wastes Using Cement: An Appraisal.

Across the world, any activity associated with the nuclear fuel cycle such as nuclear facility operation and decommissioning that produces radioactive materials generates ultramodern civilian radioactive waste, which is quite hazardous to human health and the ecosystem. Therefore, the development of effectual and commanding management is the need of the hour to make certain the sustainability of the nuclear industries. During the management process of waste, its immobilization is one of the key activities conducted with a view to producing a durable waste form which can perform with sustainability for longer time frames. The cementation of radioactive waste is a widespread move towards its encapsulation, solidification, and finally disposal. Conventionally, Portland cement (PC) is expansively employed as an encapsulant material for storage, transportation and, more significantly, as a radiation safeguard to vigorous several radioactive waste streams. Cement solidification/stabilization (S/S) is the most widely employed treatment technique for radioactive wastes due to its superb structural strength and shielding effects. On the other hand, the eye-catching pros of cement such as the higher mechanical strength of the resulting solidified waste form, trouble-free operation and cost-effectiveness have attracted researchers to employ it most commonly for the immobilization of radionuclides. In the interest to boost the solidified waste performances, such as their mechanical properties, durability, and reduction in the leaching of radionuclides, vast attempts have been made in the past to enhance the cementation technology. Additionally, special types of cement were developed based on Portland cement to solidify these perilous radioactive wastes. The present paper reviews not only the solidification/stabilization technology of radioactive wastes using cement but also addresses the challenges that stand in the path of the design of durable cementitious waste forms for these problematical functioning wastes. In addition, the manuscript presents a review of modern cement technologies for the S/S of radioactive waste, taking into consideration the engineering attributes and chemistry of pure cement, cement incorporated with SCM, calcium sulpho-aluminate-based cement, magnesium-based cement, along with their applications in the S/S of hazardous radioactive wastes.