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Procedures for Additions of Wastes to Cementitious Composites – A Review
Published in R.A. Ilyas, S.M. Sapuan, Emin Bayraktar, Recycling of Plastics, Metals, and Their Composites, 2021
M.A. de B. Martins, F.B. Pinto, D. Werdine, L. Ramon, C.V. Santos, P.C. Gonçalves, M.L.M. Melo, R.M. Barros
Portland cement is a hydraulic binder in which its hardening occurs through chemical reactions when in contact with water (Neville & Brooks, 2010). The fineness of the cement is of great importance because the larger the specific area, the greater the viscosity of the mixture. Pure cement with low tricalcium aluminate (C3A) content is the most indicated for SCC (Chen & Yang, 2015) because the high content of C3A hinders the rheological control and retards the concrete’s stiffness (Tutikian & Dal Molin, 2011). Siddique and Khan (2011) reported that the use of cementitious materials such as granulated blast furnace slag, microsilica ashes, metakaulim, limestone filler, rice husk ashes, among others, is becoming more and more commonplace. The use of such materials can be advantageous not only in reducing costs and environmental impacts, but also because it can greatly increase the final material performance of structures, such as compressive strength. In addition, some materials can help control segregation and loss of workability caused by overdosing of superplasticizers.
The development and use of non-staining cements in American masonry
Published in João Mascarenhas-Mateus, Ana Paula Pires, Manuel Marques Caiado, Ivo Veiga, History of Construction Cultures, 2021
Portland cement is an artificial cement manufactured by burning limestone, clay, shale, and/or other natural additives together to produce a desired composition. Since their inception, Portland cements have had a gray color due to their use of iron-bearing clays that produce a ferrite phase in the cement clinker. However, steps were taken at the turn of the 20th century to produce separate white Portland cements with lower iron contents to be used in non-staining applications. These are the most common non-staining cements used in American masonry mortars today and have arguably been so ever since the 1920s.
Portland Cements
Published in M. Rashad Islam, Civil Engineering Materials, 2020
Portland cement is the most widely used cement in civil engineering. This chapter deals with the manufacture of Portland cement, and its structure and properties, both when not hydrated and in a hardened state. The name, Portland cement, was given originally due to the resemblance in color to the hardened cement to Portland stone. Portland stone is a limestone quarried on the Isle of Portland, Dorset, England. The term Portland cement is used all over the world to describe a cement obtained by intimately mixing together calcareous and argillaceous (or other alumina, silica, and iron oxide-bearing) materials, burning them at a clinkering temperature, and grinding the resulting clinker. With the improvement of technology, other materials may also be added or blended to attain special properties of the cement.
Influence of firing temperature on selected mechanical properties of alluvial clay blended with a limestone and kaolin mixture
Published in Geosystem Engineering, 2023
Paulette Cathy Mengue, Michel Mbessa, Özgür Cengiz, Rodrigue Cyriaque Kaze, Thamer Salman Alomayri, Chrispin Pettang
The cement production sector is facing several significant challenges. First, limestone (CAL) deposits are finite and may be depleted, leading to an imbalance in cement production. Second, there are many issues surrounding the use of Portland cement, namely its considerable consumption due to the population boom, its high cost compared to the income of some populations, the high quantities of energy required for its production (1400 °C) and the large quantities of greenhouse gases released into the atmosphere during its production (Shi et al., 2011). This means that cement production has a negative impact on the environment (Billong, Melo, Njopwouo, et al., 2009; Singh & Middendorf, 2020). Hence, there is an urgency to develop new techniques for the production of building materials that have lower energy costs and less impact on the environment; in other words, that contribute to sustainable development.
Parametric investigation on the post-fire flexural behaviour of novel ferrocement panels with geopolymer mortar
Published in European Journal of Environmental and Civil Engineering, 2023
Therefore, the use of fire protection materials to enhance temperature enduring capacity of structural members is important and necessary. Many types of fire protection materials have been developed to protect structural members. The main classes of materials used for fire protection are cementitious, intumescent, fibrous and composite materials. Ferrocement is one of the cementitious composite materials, which is formed using hydraulic cement mortar reinforced with close spaced layers of continuous and relatively small sized wire mesh. Depending on the type of mesh used in the ferrocement, the strength gets variedly influenced. Of the meshes tested, welded wire mesh proves to provide the largest increase in strength. Portland cement is the primary cementitious material that is used in the construction industry worldwide. But the Portland cement mortar and conventional concrete are not resilient enough to withstand fire and easily undergo degradation on exposure to elevated temperatures (Gu et al., 2022). The cement industry accounts for 5–8% of worldwide CO2 emissions and cement industry is the largest producer of the greenhouse gases. It is estimated that manufacture of 1 ton Portland cement involves emission of 1 ton CO2 to the atmosphere (Davidovits, 1991). For the above reasons, recent research works are focusing on the feasibility of replacing cement with different types of waste products. Fly ash has gained prominence as the most commonly used waste material for partially replacing cement (Cao et al., 2017).
Effects of Shrinkage Reducing Admixture and Polypropylene Fiber Utilization on Some Fresh State, Mechanical and Durability Properties of Khorasan Mortar
Published in International Journal of Architectural Heritage, 2022
Tuğçe İsafça-Kaya, Kemal Karakuzu, Süleyman Özen, Ali Mardani, Adem Doğangün
The material to be used in restoration works should be chemically, physically and mechanically compatible with the original material of the building. In the 20th century, when the superiority of Portland cement was understood, these mortars were often preferred for repair purposes. However, Portland cement can cause various damages due to its high strength, low water vapor permeability and salt formation due to its chemical structure. Therefore, the problem of incompatibility with the old material may arise in repairs using Portland cement. For this reason, the use of lime-based materials as repair mortar has become widespread in recent years (Ersen, Gürdal, and Güleç et al. 2016; Izaguirre, Lanas, and Alvarez 2011; Lanas and Alvarez-Galindo 2003; Malinowski 1981; Pusat 2002).