Cement Filler Research Articles

A Review on Properties of Concrete with Magnetizing Cement

The incorporation of strong magnetic powders (NdFeB) into cement mixtures has produced improved mechanical properties of cement pastes. The magnetic cement (cementitious magnet) used a simple and inexpensive cement process to form complex forms of the NdFeB magnet. Particulate NdFeB has been distributed uniformly in the cement matrix. The magnetic cement composites increased in density and compressive strength with the NdFeB concentration. Magnetization (stable up to one year) also increased with NdFeB powder but there was no improvement in coercivity. The introduction of magnetic particles into cement matrices has also been another important method in recent years to enhance the mechanical and other properties of cement-based materials. Nanoparticles (IONs) made from iron oxide (Fe2O3, Fe2O4) are among the most popular cement fillers. Cement composites mixed with IONs showed enhanced compressive strength, as well as other enhanced functions. This paper presents literature analysis of a study of magnetizing cement on concrete properties.

STUDY OF APPROACHES TO IMPROVING DENTAL HEALTH OF DONETSK REGION RESIDENTS ON THE BASIS OF SELECTIVE ANALYSIS OF ORAL CAVITY DISEASES

The need to improve the dental health of the population does not lose its relevance and remains an unresolved medical, economic and social problem, with the need to find new approaches to the provision of dental care.The aim of the study was to determine the effectiveness of preventive measures and public awareness of the course and consequences of dental pathology in order to improve dental health.To achieve this goal, the data of the annual reports of municipal dental services of Donetsk region were analyzed and a survey with additional functional (electromyography and digital analysis of occlusion) examination of the dental status of 200 people was conducted.Thus, in 2018, the number of primary visitors to therapeutic departments within the region included 718097 people. Patients who underwent primary preventive measures included: hygienic training and education, individual choice of prevention only 21.09% of the total number of people.Within the survey, 82.5 % did not understand the dependence of hygiene and carious processes, 75.5% had no information about the need for quality restoration of the anatomy of the dentition, and 21.5 % did not understand the need to replace the final defects of the dentition. It has been found some reflection of these facts in the analysis of annual reports. Thus, the percentage of filled teeth due to caries or its complications to removed teeth, for the same reasons, was 46.46 %. A similar result in 46.58 % was the number of patients who applied after the removal of teeth to the orthopedic department in order to restore the integrity of the dentition (removable, conditionally removable, non-removable structures). But in addition to the lack of full restoration of the dentition, it was found that the ratio of total filled teeth to cement fillings was 44.5 percent of all filled teeth due to both caries and its complications. 44.5 % was the restoration of lost tooth tissues using cements (zinc phosphate and SIC). Due to the impossibility of restoring quality anatomy, and as a result of the function of the tooth, such a percentage does not meet the needs of today in understanding quality dental services.Based on the results of the analysis of the study data, we concluded that patients are poorly informed about their condition, variations in their treatment and the consequences of lack of comprehensive treatment, the causes and consequences of certain dental conditions and prevention. The results of our surveys and diagnostic tests revealed the need for modern and objectively motivated approach to diagnosis and informing patients about their condition, which leads to a better understanding of the cause-and-effect relationships and the desire for full rehabilitation.In turn, this not only improves dental health at the end of treatment, but also helps to maintain it for a long time, which in turn improves the social and economic life of the patient.

Reducing Environment Pollution by Reusing of Alum Sludge Waste in Stone Mastic Asphalt Mixtures

Globally, a huge quantity of alum sludge waste is produced as a by-product material from drinking water treatment plants that utilize aluminum salts as an essential coagulate and is the most generally produced water treatment remaining sludge around the world, which causes a serious environmental problem. Direct discarding of this substance has ecological effects. Hence, it is important to reuse this alum sludge waste material in such a manner to diminish its detrimental impacts on the environment. This research investigates the possibility of reusing alum sludge waste as a partial replacement of cement filler in stone mastic asphalt (SMA) paving mixtures. For this investigation, the alum sludge was used as a filler material in SMA mixtures in two modes; dried alum sludge at 110°C and burned alum sludge at 700°C. Different percentages of alum sludge were used as a replacement by the total weight of mineral filler at 0, 20, 40, 60, 80, and 100%. The results showed that using alum sludge as a substitution of filler in SMA mixtures reduces the performance of the mixtures in terms of Marshall properties and tensile strength for both dried and burned alum sludge compared with a standard mix. However, the performance of the mixtures containing burned alum sludge gave a better performance than the mixtures containing dried alum sludge.

Cementitious Fillers in Cement Asphalt Emulsion Mixtures: Long-Term Performance and Microstructure

Cementitious Fillers in Cement Asphalt Emulsion Mixtures: Long-Term Performance and Microstructure

Roles of Waste Glass and the Effect of Process Parameters on the Properties of Sustainable Cement and Geopolymer Concrete-A State-of-the-Art Review.

Recent research has revealed the promising potential of using waste glass (WG) as a binder or inert filler in cement and geopolymer concrete to deliver economic and environmental benefits to the construction sector. However, the outcomes obtained by different research groups are scattered and difficult to compare directly because of isolated process parameters. In this study, the roles and impacts of WG and process parameters on the performance of WG-added cement and geopolymer concrete are critically reviewed. This study reveals that the chemical and mineralogical composition, and particle size of WG, mix proportion, activation, and curing condition of concrete are the most important parameters that affect the dissolution behavior of WG and chemical reactivity between WG and other elements in concrete; consequently, these show impacts on properties of concrete and optimum WG level for various applications. These parameters are required to be optimized based on the guidelines for high pozzolanicity and less alkali–silica reactivity of WG in concrete. This review provides a critical discussion and guidelines on these parameters and the chemistry of WG in cement and geopolymer concrete for best practice and highlights the current challenges with future research directions.

Characteristics of Lapis Intermediate Mixture Using Straw Ash as a Filler Substitution Material

This study aims to determine the characteristics the mixture of intermediate layers using straw ash as a substitute for cement filler. The method in this research is to test the characteristics of the straw ash, then design the composition of the intermediate lastton mix, as well as the marshall test to obtain the characteristics of the intermediate layer of lastton using straw ash as a cement filler substitution. Where the ash content of straw used as a substitute for cement filler is 0%, 25%, 50%, 75%, and 100% of the weight of cement filler. The results showed that the stability, Flow, VIM, VMA, and VFB at 0%, 25%, 50% straw ash content met the 2018 bina marga specifications, while VMA at 75% straw ash content did not meet the 2018 bina marga specifications, and VMA, VFB at 100% straw ash content also does not meet the 2018 bina marga specifications.

The impact of different dental restorations on detection of proximal caries by cone beam computed tomography.

To evaluate the effects of different types of restorations on observer ability to detect proximal caries in CBCT images. Forty human premolars and molars with artificial proximal caries were placed proximal and distal to 5 molars having different restorations (amalgam, composite, resin-modified glass ionomer cement (RMGIC) fillings, zirconia, and lithium disilicate crowns) and a non-restored molar. CBCT scans were obtained using i-CAT®Next Generation. Images were rated twice by 2 observers. The exact depth of artificial caries was histologically established. Sensitivity, specificity, and area under the receiver operating characteristic curve (Az) values were calculated. Caries detection in teeth surfaces mesial and distal to amalgam showed compromised specificity and accuracy. Moreover, caries detection in teeth surfaces mesial to zirconia crown showed low sensitivity, specificity, and accuracy. Capability of CBCT in detection of proximal caries in teeth adjacent to composite, RMGIC, and lithium disilicate was comparable to those adjacent to non-restored molar. CBCT scans performed for tasks other than caries detection should be assessed for proximal caries in absence of any restorations as well as in presence of composite, RMGIC fillings, and lithium disilicate crowns. However, CBCT should not be used for proximal caries detection in teeth adjacent to amalgam and teeth surfaces mesial to zirconia crowns. It is important to investigate the influence of artifacts produced by various restorations on CBCT-based caries detection to optimize CBCT benefits, caries diagnosis and avoid unnecessary treatment of sound surfaces.

Utilization of Styrofoam Waste as Additive to AC-BC Mixture Using Bittuang River

This study was intended to determine the characteristics of the mixture of intermediate layers of concrete with the addition of styrofoam waste in the mixture of intermediate layers of concrete. The composition of the mixture of intermediate lasts and Marshall test to get the characteristics of the mixture of intermediate layers of concrete with the addition of straw ash Styrofoam waste as a cement filler substitution. The results of testing the characteristics of the Asphalt Concrete – Binder Course (AC-BC) mixture using Styrofoam waste added material through the Conventional Marshall test, namely if the Styrofoam waste content is 1%, then the VIM, VMA, and Flow values decrease at each Styrofoam waste level, while for Stability and VFB values always increase at each level of Styrofoam waste. The Marshall Immersion test results obtained a Stability value of the mixture that could withstand Immersion for 24 hours.

Retrospective physical dosimetry in the Czech Republic: an overview of already established methods and recent research

Purpose The threat of serious radiation exposures to members of the public from radiological incidents and nuclear events has led to intensive study of a number of emergency dosimetry techniques for purposes of triage. As such, a national laboratory of retrospective dosimetry was established in our institute. The purpose of this work is to provide a summary of the well-established and already implemented retrospective physical dosimetry techniques based on thermoluminescence (TL), optically stimulated luminescence (OSL) and neutron activation including their specifics. Moreover, we present some new results of the experimental work, in which we compared dosimetry potential of various dental repair materials and human teeth. Materials and methods At first, an overview of already established retrospective physical retrospective methods including their main features was compiled. As regards recent research, an experimental comparative study was performed under defined conditions. The materials used were aliquots prepared from both pure and repaired teeth and aliquots of unused dental ceramics of known type. Following irradiation, we compared TL and OSL curves of the materials. We also compared dosimetry characteristics of OSL signal as reproducibility, dose dependence and fading. Results After irradiation, the teeth aliquots of dental enamel and dentin exhibited very low OSL and TL signals compared with aliquots containing some dental repair materials or aliquots of pure dental ceramics. With a few exceptions, the OSL signal of dental enamel and dentin aliquots irradiated to 2 Gy was hardly distinguishable from OSL signal corresponding to unirradiated aliquots. In contrast, aliquots of teeth containing some dental repair material and aliquots of pure dental ceramics provided a well reproducible OSL signal exhibiting linear dose response. All the materials tested exhibited a significant fading of the OSL signal. The loss of OSL signal during the first 24 hours after irradiation was from 20 to 99% of its original value obtained immediately after the irradiation. Conclusions The already established physical methods of retrospective dosimetry use a spectrum of verified materials and techniques for dose assessment in the aftermath of serious radiological incidents and nuclear events. In the comparative study, we found that the dosimetry potential of teeth in natural state is much worse compared to teeth repaired with dental ceramics or dental cement fillings. Teeth restored with dental repair materials exhibited relatively favorable dosimetry characteristics. However, they can be usable for a dose reconstruction only on condition that the main practical problems connected with fading and optical bleaching were solved.

Petrography, geochemistry and industrial quality of the Etono limestone in Ugep Southwest, Southeastern Nigeria

Petrographic and geochemical analyses were carried out on limestones occurring in Etono, Southwest Ugep, Southeastern Nigeria to determine their chemical composition, industrial uses and classification. Samples of limestone in the area were subjected to petrographic study and analyzed geochemically using Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) and X-Ray Fluorescence (XRF) techniques. The petrographic analysis reveals that the Etono limestone contains high percentage of carbonate materials with scanty organic remains and patches of iron. The bulk- rock composition of the limestone shows that the average SiO2 = 9.02%, Al2O3 = 1.95%, Fe2O3 = 2.08%, MgO = 0.39%, K2O = 0.47%, Na2O = 0.00%, CaO = 47.92%, SO2 = 0.24% and LOl = 37.37%. The limestone is classified based on their moderately high CaO, SiO2 and LOl and very low MgO. The mean CaO (47.92%) of Etono Limestone is high relative to the mean CaO of Agoi Ibami Limestone (43.83%) but low relative to the Mfamosing Limestone (55.30%) and the mean SiO2 values of 9.02% is high relative to Mfamosing Limestone (0.38%) but low relative to Agoi Ibami Limestone (13.93%). Results of the geochemical investigation reveal a shallow marine environment of deposition (EOD) for Etono Limestone. The higher values of CaO and LOl and lower values of SiO2 of the limestone suggest that it can be used for cement production, building stone, filler and agricultural purposes.

Effect of lime and cement fillers on moisture susceptibility of cold mix asphalt

Cold mix asphalt (CMA) has many economic and environmental benefits but its higher moisture susceptibility reduce its use to minor construction and repairing work. To increase the field implementation of CMA, it is very necessary to reduce its moisture susceptibility. So present study examines the effect of lime and cement filler on the moisture susceptibility of CMA. In the study, lime and cement fillers were used in varying proportions i.e. 1% to 5%. Based on volumetric properties and minimum emulsion content criteria, 2% was found to be optimum content for both lime and cement fillers. From Marshall stability, retained Marshall stability, Indirect tensile strength, and Tensile strength ratio values it was found that both fillers considerably improve moisture susceptibility of cold mixes. Energy consumption and cost comparison further concluded that as compared to HMA, incorporation of cement and lime fillers in cold mixes results in economic and environment-friendly mixes.

Thermally Treated Waste Silt as Filler in Geopolymer Cement.

This study aims to investigate the feasibility of including silt, a by-product of limestone aggregate production, as a filler in geopolymer cement. Two separate phases were planned: The first phase aimed to determine the optimum calcination conditions of the waste silt obtained from Società Azionaria Prodotti Asfaltico Bituminosi Affini (S.A.P.A.B.A. s.r.l.). A Design of Experiment (DOE) was produced, and raw silt was calcined accordingly. Geopolymer cement mixtures were made with sodium or potassium alkali solutions and were tested for compressive strength and leaching. Higher calcination temperatures showed better compressive strength, regardless of liquid type. By considering the compressive strength, leaching, and X-ray diffraction (XRD) analysis, the optimum calcination temperature and time was selected as 750 °C for 2 h. The second phase focused on determining the optimum amount of silt (%) that could be used in a geopolymer cement mixture. The results suggested that the addition of about 55% of silt (total solid weight) as filler can improve the compressive strength of geopolymers made with Na or K liquid activators. Based on the leaching test, the cumulative concentrations of the released trace elements from the geopolymer specimens into the leachant were lower than the thresholds for European standards.

Influence of ternary blended cementitious fillers in a cold mix asphalt mixture

The manufacture of conventional hot mix asphalt (HMA) for paving has a substantial environmental footprint, and the production of clean asphalt mixture with good engineering performance is critically important. The introduction of cementitious filler is a promising approach to achieve outstanding mechanical properties for cold mix asphalt (CMA) as a clean paving material. This study aims to develop a novel CMA formulation through the combination of ordinary Portland cement (OPC) with two industrial by-products: fly ash (FA) and ground-granulated blast furnace slag (GGBS), which could make CMA even cleaner. To achieve this objective, the effects of ternary blended cementitious fillers on the early-age strength, engineering performance, and microstructural properties of CMA are characterized through comprehensive laboratory tests. The experimental results indicated that the indirect tensile strength of CMA-B containing 2% OPC, 1% FA, and 1% GGBS is approximately 20% higher than that of the mixture with 2% OPC (CMA-2% OPC). The residual Marshall stability ratio of CMA-B was increased to about 95% and its dynamic stability was approximately 10 times that of CMA-2% OPC. Employing blended cementitious fillers in CMA facilitates the formation of hydration products with excellent stiffness, reduces the air voids, and enhances interface bonding between aggregate and asphalt matrix, and thus suitable for applications in road pavements subjected to harsh service conditions in terms of moisture and temperature.

Ceramic composite with gentamicin decreases persistent infection and increases bone formation in a rat model of debrided osteomyelitis.

Introduction: Current methods of managing osteomyelitic voids after debridement are inadequate and result in significant morbidity to patients. Synthetic ceramic void fillers are appropriate for non-infected bone defects but serve as a nidus of re-infection in osteomyelitis after debridement. CERAMENT G (CG) is an injectable ceramic bone void filler which contains gentamicin and is currently being evaluated for use in osteomyelitic environments after debridement due to its theoretical ability to serve as a scaffold for healing while eliminating residual bacteria after debridement through the elution of antibiotics. The goal of this study was to evaluate (1) the rate of persistent infection and (2) new bone growth of a debrided osteomyelitic defect in a rat model which has been treated with either gentamicin-impregnated ceramic cement (CERAMENT G) or the same void filler without antibiotics (CERAMENT, CBVF). Methods: Osteomyelitis was generated in the proximal tibia of Sprague Dawley rats, subsequently debrided, and the defect filled with either (1) CG (), (2) CBVF (), or (3) nothing (). Each group was euthanized after 6 weeks. Infection was detected through bacterial culture and histology. Bone growth was quantified using microCT. Results: Infection was not detected in defects treated with CG as compared with 35 % of defects () treated with CBVF and 50 % () of empty defects (). Bone volume in the defect of CG-treated rats was greater than the CBVF (0.21 vs. 0.17, ) and empty groups (0.21 vs. 0.11, ) at 6 weeks after implantation. Conclusions: Ceramic void filler with gentamicin (CERAMENT G) decreased the rate of persistent infection and increased new bone growth as compared to the same void filler without antibiotics (CERAMENT) and an empty defect in a rat model of debrided osteomyelitis.

РОЛЬ ГРАНУЛОМЕТРИИ СМЕШАННЫХ ВЯЖУЩИХ В ФОРМИРОВАНИИ ИХ МИКРОСТРУКТУРЫ И ПРОЧНОСТИ

A complex system is formed when grinding Portland cement and various mineral fillers. It consists of grains of various sizes with a predominance of a highly dispersed phase. The work investigates the effect of mixed binders prepared on the basis of Portland cement and volcanic ash at various dosages. The analysis of volcanic ash particles is carried out. It is found that the presence of the smallest fractions in the range from 0.3 to 0.07 microns predicts active interaction in the system and the filling of the pore space with hydration products. It has been established that mixed binders obtained by mechanical mixing (without grinding) with a content of 10% volcanic ash have a strength 13% higher than no addition cement. Mixed binders activated by milling in a vibration mill with a volcanic ash content of 10% are characterized by an increase in compressive strength by 22%, which saves Portland cement by up to 10%. Mixed binders with a volcanic ash content of 20% correspond to the strength of cement free. The results obtained indicate the effectiveness and feasibility of using volcanic ash as a mineral component of mixed binders. The microstructure of a cement stone sample from an activated mixed binder is highly homogeneous, dense intergrown plates of a secondary hydrosilicate structure are clearly visible in the sample cleavage, and crystalline products of pozzolanic reactions between ash particles and cement hydration products are formed on the surfaces of secondary hydrosilicate structures. The purpose of this article is to study the role of granulometry of mixed binders in the formation of their microstructure and strength.

Refractory Concrete Based on High-Alumina Cement and Clinker Filler

Refractory Concrete Based on High-Alumina Cement and Clinker Filler

A PSO-ANN Intelligent Hybrid Model to Predict the Compressive Strength of Limestone Fillers Roller Compacted Concrete (RCC) to Build Dams

The compressive strength of the roller-compacted concrete (RCC) is an essential indicator of quality when designing dams. RCC is optimized in most cases through experimental studies conducted vigorously. This study aims at developing a smart system to predict the compressive strength of the limestone fillers RCC that is used to build dams. The prediction is made base on the following parameters: the maximum diameter of the aggregates, the compactness of the granular mixture, the rates of both cement and limestone fillers, water/cement ratio and the RCC age. The cement strength is taken in to consideration using a corrective equation. Two metaheuristic systems are developed: artificial neural networks (ANN), and a hybrid system consisting of an ANN optimized by a particle swarm optimization (PSO) algorithm. An experimental database is built containing 500 vectors taken from RCC formulations given by lab activity reports about 04 dam projects. The best results were achieved through the PSO-ANN hybrid system. This prediction system is validated by an experimental study conducted on 20 RCC formulations, and a comparison was made with the Laboratoire Central des Ponts et Chaussees (LCPC) method. The prediction resulting from the PSO-ANN system is of a good accuracy level with a correlation factor R2 = 0.85 and a low root mean squared error of 1.45. Finally, a user interface based on the model developed is created.

Palaeozoic stromatoporoid diagenesis: a synthesis

Palaeozoic stromatoporoids, throughout their 100-million + year history (Middle Ordovician to Late Devonian and rare Carboniferous), are better preserved than originally aragonite molluscs, but less well-preserved than low magnesium-calcite brachiopods, bryozoans, trilobites and corals. However, the original mineralogy of stromatoporoids remains unresolved, and details of their diagenesis are patchy. This study of approximately 2000 stromatoporoids and the literature recognises three diagenetic stages, applicable throughout their geological history. Timing of processes may vary in and between stages; some components are not always present. Stage 1, on or just below sediment surface, comprises the following: micrite filling of upper gallery space after death, then filling of any remaining space by non-ferroan then ferroan calcite in decreasing oxygen of pore-waters; partial lithification of associated sediment from which stromatoporoids may be exhumed and redeposited, evidence of general early lithification of middle Palaeozoic shallow-marine carbonates; microdolomite formation, with the Mg interpreted to have been derived from original high-Mg calcite (HMC) mineralogy (likely overlaps Stage 2). Stage 2, short distance below sediment surface, comprising the following: fabric-retentive recrystallisation (FRR) of stromatoporoid skeletons forming fabric-retentive irregular calcite (FRIC), mostly orientated normal to growth layers, best seen in cross-polarised light. FRIC stops at stromatoporoid margins in contact with sediment and bioclasts. FRIC geometry varies, indicating some taxonomic control. Evidence that FRIC formed early in diagenetic history includes syntaxial continuation of FRIC into some sub-stromatoporoid cavities (Type 1 cement), although others were pre-occupied by early cement fills (Type 2 cement) formed before FRR, preventing syntaxial continuation of FRIC into cavities. Likely contemporaneous with FRIC formation, stromatoporoids in argillaceous micrites drew carbonate from adjacent sediment during reorganisation of argillaceous micrite into limestone–marl rhythms that are also early diagenetic. Stage 3, largely shallow burial, comprises the following: dissolution and silicification, but these may have occurred earlier in stromatoporoid diagenetic histories (more data required); burial pressure dissolution forming stylolites.

The Filler Effect on Compressive Strength of Sulfur Concrete

The sulfur concrete samples were prepared by the optimized process, which were mixed with cement, fly ash and slag, respectively. The influence of the type and content of filler on the compressive strength of sulfur concrete was studied. The phase and micromorphology of filler and sulfur mixture were characterized by X-ray diffraction and scanning electron microscope, and the bonding mode was studied. The results show: the cement filler has the best effect on the compressive performance of sulfur concrete,and the compressive strength is 87.2 MPa by adding cement filler with the same quality as sulfur; there is no chemical reaction between filler and sulfur, and the filler is physically bonded to sulfur matrix.

Texture Depth and Cost Analysis of Slurry Seal Cationic Rapid Setting Cold Asphalt Mixture

Slurry seal is a mixture of asphalt emulsion, fine aggregate, mineral filler, water, and other added ingredients are mixed evenly without heating and is spread over the surface of the pavement with a maximum thickness of 10 mm. This study was conducted to determine the relationship of the depth texture and skid resistance resulting from the modification of the aggregate and filler slurry seal based texture depth test of sand patches. Slurry seal is made using basalt stone aggregate filler Ordinary Protland Cement (OPC), limestone filler aggregate OPC and aggregate rock with filler standard OPC composition: High Calcium Fly Ash 50%: 50%. Increasing the texture depth will add road surface roughness. Slurry seal with basalt stone aggregate having the largest texture depth is 1.837 mm so as to provide the greatest improvement of skid resistance. Texture depth slurry seal with limestone aggregate is 1,767 mm that mean increasing skid resistance. Slurry seal standard aggregate has a depth of 1,673 mm texture which represents an increase skid resistance smallest slurry seal between basalt stone aggregate and limestone. Slurry seal with cheapest price is limestone slurry seal aggregate Rp. 44,817.00 / m2 compared basalt aggregate Rp. 45,085.00 / m2 and a standard stone mixture of cement and fly ash filler Rp. 44,914.00 / m2.