Review Article
Jan 01, 2022
Traditional concrete is a mixture of Portland cement, aggregates, water and admixtures. The principal binder in concrete is Portland cement, the production of which consumes high energy, costly, depletes natural resources and is a major contributor to green-house gases (GHG) emission that is implicated in global warming and climate change. Every ton of Portland cement production releases about 1 ton of CO2 into the atmosphere. If the world produces 3.5 billion tons of cement per year, it emits approximately the same amount of CO2 in the atmosphere every year, just from one industry. Moreover, concrete consumes more than 8 billion tons of aggregates every year, which also depletes the natural resources, thus causing additional problems to ecology and environment. On the other hand, millions of tons of agriculture, industrial and natural waste materials (fly ash, etc.,) are abundantly available in the world and are wasted every year. Most of them may contain one or more of hazardous and toxic chemicals from trace amount to several percentages. The majority of these unused wastes are dumped in landfills, quarries, rivers and oceans, exacerbating environmental concerns like air pollution, leaching into soil and water. Studies have shown that some of these waste materials have been and are being used successfully in all kinds of existing and future concrete structures by replacing cement, sometimes up to 70%. They reduce not only ecology, environmental pollution and energy but also produce stable, more durable and economical sustainable construction materials. This paper discussed the issues and solutions related to the reduction in ecology, environment, economy and energy in concrete industry using waste materials.
Research Article
Nov 08, 2021
The objective of this work is to characterize two materials in order to synthesize anticorrosive coating. These materials are an oolitic iron oxide pigment containing phosphorus and a by-product of steel making that should be recycled. The characterization of these two components took place in the URASM / CRTIAnnaba laboratories. Chemical analysis showed that the pigment contains 53.18% iron and a siliceous gangue. The scale contains 73.83% iron as iron oxides (FeO, Fe3O4 and Fe2O3). Grinding tests have shown that the scale is much more suitable for grinding than pigment. A volume distribution of particles ranging in size from 0.7 to 32 microns for the scale and from 0.6 to 40 microns for the pigment; their specific areas are between 1.6 and 1.5 m2/g. TGA and DSC analyzes have shown that the pigment loses weight with phase dissolution by consuming energy as the temperature increases. The scale is gaining weight by forming a new phase with heat. At SEM, the iron pigment is in the form of an aggregate of grains surrounded by gangue. Scale showed a homogeneous structure composed of iron oxide grains of sizes and shapes ranging from 1 μm to 10 μm. X-ray diffraction analysis showed that the iron in the pigment was in the form of hematite and goethite. A tiny portion is combined with silica as Fe2SiO4. Iron in Scale is in the form of three oxides (FeO, Fe2O3 and Fe3O4). The different coating formulations used have shown that a mixture of 71.43% pigments and 28.57% scale has the best corrosion resistance, resulting in low current and low corrosion rate.
Research Article
Mar 09, 2021
Not applicable
Research Article
Nov 02, 2020
The manufacture of steel and Portland cement (PC) consumes enormous raw material resources. The manufacturing processes involved are associated with high-energy consumption, unsightly excavations, especially when left without attention to landscaping, and most negatively exacerbate atmospheric pollution. PC forms the main binder material in concrete and represents the costliest constituent in concrete and masonry. Therefore, the environmental and economic impact of PC is huge. It is responsible for about 10% of the global human derived carbon dioxide emissions. For these reasons, the possibility of replacing, or minimizing usage, of the traditional building and construction materials with low-cost greener materials from nature, industry or agriculture will yield significant benefits, and numerous researches have been undertaken on different waste materials. Research so far in this direction is incomplete and more coverage is required. Pending issues relate to durability, versatility as a building material, so as to resolve issues related with domestic fixtures (shelves etc.), jointing, demolition and/or re-use among others. Most of the major waste and by-product streams have been explored, leaving only marginal and waste materials. This paper explores these issues, with the aim of enhancing the uptake of earth-based raw materials from nature, industry or from agricultural sources.
Research Article
Mar 03, 2020
In this research, the unsaturated polyester resin (polylite 420-852) ise used in combination with bidirectional jute fiber to generate composites materials by a contact molding technique. The parameter which was carried out on the prepared samples was impact test to plot the S-N curve, which is based on Wöhler Equation. Two-parameter Weibull probability was used for analysis statistically the fatigue life results of composite jute/polyester samples. Weibull graphic was plotted for each loading level using fatigue data. Then, S–N curves were drawn for different reliability levels (Ps = 99%, Ps =90%, Ps =50%, Ps = 36.8% and Ps = 10%) using Weibull data. These S-N curves were introduced to the identification of the first failure time as reliability and safety limits of the material.
Research Article
Mar 02, 2020
Water exists in nature with three forms as; aboveground water resources such as river, lake, and sea, underground water resources and water vapour in atmosphere. Ceramic-structured construction materials such as concrete, stone, brick are intrinsically porous materials. Porous systems, which exist in construction materials, are decreased or construction systems are insulated against water by using waterproofing materials to protect construction systems from water impact. Within essential construction materials, some additives with cement are used in concrete production in order to reduce the amount of porosity, improve qualities, increase durability and ensuring affordability of concrete in a particular way. In this study, the effect of wheat straw ash, which is one of the pozzolanic materials, investigated with the aim of reducing the amount of porosity and size of concrete, preventing continuity of capillary pores, minimizing their permeability and improving concrete strength qualities.
Research Article
Jan 07, 2020
Aim of this study is to evaluate the upcycling of oil shale ash (OSA) for highway concrete compacted with roller known as roller compacted concrete (RCC). The RCC specimens were prepared replacing 0%, 10%, 20%, 30%, and 40% OSA with cement to measure unit volume mass, compressive strength, flexural strength, and loss on unit volume mass and compressive strength after freezing and thawing cycles. The results showed that the upcycling of OSA done in current study has effective method on the properties of the RCC tested. The RCC specimens containing 10% OSA reached the compressive strength, greater than 35 (MPa) at 28d. Based on the experimental results, it is possible to use the OSA in manufacturing of highway concrete compacted with roller. Additionally, the work as upcycling example would help to reduce the quantity of OSA and to improve the properties of cement-based material and to reduce the cost of construction and to protect the environment from harmful effect of manufacturing of oil and cement.
Research Article
Jan 07, 2019
Aim of the work is at presenting the specifications effected in durability of varying construction materials used in construction technology, e.g indoor finishing application, pavement application, and masonry brick working application. These tested construction materials are the wall brick, the interlocking concrete block, the wood foamboard panel, and the construction granite. As the service life of construction material is affected by water movement, the tested water durability specifications are the capillarity and water permeability in the current study. All tests demonstrated that the construction materials were suitable to use in the construction technology effectively.
