Calculation of Cement Composition Using a New Model Compared to the Bogue Model

The major cement composition ratios of alite, belite, aluminate, and ferrite have been calculated with the Bogue models until now. However, a recent comprehensive analysis based on various experimental data has revealed that the chemical composition of alite, belite, aluminate, and ferrite implemented by the Bogue models are slightly different than the experimental data, where small amounts of Al2O3 and Fe2O3 existing in alite and belite can change the prediction of cement composition. Since the amounts of cement compound are very important factors in determining the properties of concrete, improvement in the calculation would give more precise prediction for application usages such as climate change adaptable cement and high durable concrete manufacturing. For this purpose, 20 new models are proposed by modifying chemical compositions of the cement compounds and verified with the 50 experimental data sets. From the verification, the most accurate models are identified. The calculation using new models exhibit an accuracy improvement of approximately 5% compared to the Bogue models. Their applicable range is also presented. The study results are discussed in detail in the paper.

A Review on Using ANOVA and RSM Modelling in The Glass Powder Replacement of The Concrete Ingredients

The flat glass powder usage instead of sand is convenient in structurally serviceable and environmentally compatible concrete. The deposits of glass powder in fibres cement compounds manufacture may add significant technical, economic and environmental necessities. The cement material and cement replacement by glass powder is chosen as parameters of the concrete. When the waste glass is fined to very fine dust, it demonstrates a cementitious characteristic due to silica content. Statistical methods and techniques are heavily used in glass powder replacement. In this paper, fifteen papers are reviewed and investigated to check the availability of using the statistical and modelling system in discussing the glass powder replacement with some other ingredients results between 2012-2021. We found that most of the papers depended on the ANOVA test to perform their work. Moreover, central composite face-centred (CFC) and Response Surface Methodology (RSM) took a part in the studies. From the numerous replicas, a quadratic prototypical was supplied with waste glass powder in the numbers of the studies that the glass waste powder is the best with its characteristics.

Influence of soda-lime waste glass microparticles on workability and thermal properties of portland cement compounds

Numerous studies have investigated the use of waste glass as a partial substitution in Portland cement. Nonetheless, it seems there is no consensus about the influence of particle size and color on the behavior of the compounds. This work investigates the influence of soda-lime glass microparticles on the properties of cement and mortar in both fresh and hardened states. The effects of partial substitution (10 and 20%) of the cement by colorless and amber glass particles with dimensions of approximately 9.5 mm were investigated. The results revealed that the substitutions did not significantly affect the setting times, nor the mechanical properties of mortar at longer curing times. The influence of glass content and chemical composition on workability and hydration heat was also observed. The waste glass samples showed lower thermal diffusivity than the control sample. Thermal emissivity was not influenced by the presence of glass microparticles.

UTILISATION OF SLAG POWDER FOR CEMENT SUBSTITUTION BASED ON THE COMPRESSIVE STRENGTH AND PENETRATION OF CHLORIDE IONS

UTILIZATION OF SLAG POWDER FOR CEMENT SUBSTITUTION BASED ON THE COMPRESSIVE STRENGTH AND PENETRATION OF CHLORIDE IONS. The availability of waste from nickel ore smelting in the form of slag has increased, this is due to the high nickel production to meet the increasing needs for development and for compound- ing materials for construction materials. This research aims to make a paste from the mixture of Nickel Pig Iron (NPI) slag from PT Indoferro which is used as a substitute for making cement paste. The materials used in this study are cement, nickel slag, water, and zeolite. The cement paste is made with a dimension of 10 cm x 5 cm with each slag used as an amplifier on the paste with a volume variation of 15%, 30%, 45%, and 60%. Each material is weighed according to mix design then mixing the materials, after they are homogeneous, they are put into the mold and then let stand for 24 hours until the paste solidifies and hardens, after 24 hours, the paste sample is removed from the mold and treated at room temperature, after the life is qualified, the paste sample is tested. Results of the compression test show that variations of slag addition to the paste mixture giving maximum compressive strength is the 15% variant for NPI slag. The increase in compressive strength of the slag mixture paste may occur because slag contains cement compounds which can chemically react with Calcium Hydroxide (CH) com- pounds as a result of the hydration reaction of cement with water to form a Calcium Silicate Hydrate (CSH) compound from the hydration result between water and cement to increase adhesion and compressive strength on cement paste.

USE OF ZEOLITE IS ACTIVATED AS SUBSTITUTION OF CEMENT FOR PRICE AND COST

The number of economic needs is one of the fundamental aspects to support the survival of every individual in an area. If seen in general, the cost of building the building and residential community still use building materials and installation costs are relatively higher. With the advancement of technology has found a lightweight brick that has better strength, lighter, faster installation and environmentally friendly, so many people began to switch to using lightweight bricks. For now the price of lightweight brick is still expensive, but this deficiency is covered with the speed of mounting and light weight so overall lightweight brick usage on certain patterns is very profitable. The use of cement on lightweight bricks leads to high production costs. With the above problems we have a breakthrough to replace the cement by using zeozolites containing silica compounds that resemble one of the cement compounds. In this research, cement replacement with Zeolite is 20%, 40% and 60%. Before use Zeolite was first activated using Fly Ash ratio of 65% Zeolite: 35% Fly Ash and 50% Zeolite: 50% Fly Ash, also activated using Ca (OH) 2 ratio 65% Zeolite: 35% Ca (OH) 2 And 50% Zeolite: 50% Ca (OH) 2. Thus, there are 15 compositions including the control composition, each composition will be made up of 10 specimens. Hypothesis testing using two way anova, tested is the effect of cement change treatment with Zeolite and comparison of Zeolite composition with Fly Ash and Ca (OH) 2 to compressive strength, absorption and cost. Keywords: Zeolite, Cement, compressive strength, Cost

Propiedades mecánicas de morteros de cemento con adiciones de fibras de carbono, nanotubos de carbono y grafeno = Mechanical properties of cement mortars with additions of carbon fibres, carbon nanotubes and graphene

El carbono es uno de los elementos más abundantes de la naturaleza. Su particular estructura hace que pueda tener hasta cinco tipos distintos de alótropos. Durante los últimos años se han producido grandes avances en el estudio de estos materiales de carbono. Las fibras de carbono (CF), los nanotubos de carbono (CNTs) y el grafeno y óxido de grafeno (GO), en función de su estructura y su escala, presentan unas propiedades notablemente diferenciadas. Este estudio pretende comparar y determinar los efectos de estas características en matrices de cemento. Las características de estos materiales son difíciles de transmitir de forma exacta a los compuestos de cemento y hormigones, principalmente por las dificultades que presentan los nanomateriales en su dispersión. Por ello, los datos obtenidos en distintos estudios muestran resultados muy variables. Sin embargo, se ha demostrado que, para mejoras medias, los nanomateriales resultan ser más eficientes.AbstractCarbon is one of the most abundant elements of nature. Its particular structure has to have up to five different types of allotropes. During the last years there have been great advances in the study of these carbon materials. Carbon fibers (CF), carbon nanotubes (CNT) and graphene and graphene oxide (GO), depending on their structure and scale, have remarkably different properties. This study aims to compare and determine the effects of these characteristics on cement matrices. The characteristics of these materials are difficult to transmit accurately to concrete and cement compounds, mainly due to the difficulties presented by nanomaterials in their dispersion. Therefore, the data obtained in different studies, results, very variable. However, it has been shown that, for average improvements, nanomaterials are more efficient.