Waste Slag from Heating Plants as a Partial Replacement for Cement in Mortar and Concrete Production. Part I—Physical–Chemical and Physical–Mechanical Characterization of Slag

Numerous factors influence the complexity of environmental and waste management problems, and the most significant goal is the reuse of materials that have completed their “life cycle” and the reduction in the use of new resources. In order to reduce impact of waste slag on the environment, in the present study, waste slag, generated in heating plants after lignite combustion, was characterized in detail and tested for application as a replacement for cement in mortar or concrete production. For physical–chemical characterization of slag, different experimental and instrumental techniques were used such as chemical composition and determination of the content of heavy metals, investigation of morphological and textural properties, thermal analysis, X-ray, and infrared spectroscopy. Physical–mechanical characterization of slag was also performed and included determination of activity index, water requirement, setting time and soundness. A leaching test was also performed. Presented results show that waste slag may be used in mortar and concrete production as a partial cement replacement, but after additional combustion at 650 °C and partial replacement of slag with silica fume in the minimal amount of 12%. The maximal obtained cement replacement was 20% (17.8% slag and 2.2% of silica fume).

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Application of Lignite Combustion Waste Slag Generated in Heating Plants as a Partial Replacement for Cement. Part II: Physical–Mechanical and Physical–Chemical Characterization of Mortar and Concrete

Minerals ◽

10.3390/min11090925 ◽

2021 ◽

Vol 11 (9) ◽

pp. 925

Author(s):

Milan Kragović ◽

Nenad Ristić ◽

Jelena Gulicovski ◽

Andrijana Nedeljković ◽

Snežana Pašalić ◽

...

Keyword(s):

Construction Material ◽

Chemical Characterization ◽

Physical And Mechanical Properties ◽

Partial Replacement ◽

Test Results ◽

Cement Replacement ◽

Physical Chemical ◽

Standard Procedures ◽

Concrete Production

The presented study is a continuation of the research with the aim of finding a useful value of hazardous waste slag generated by the combustion of lignite in heating plants and its application in the construction industry. The different amounts of cement (10, 15, 20 and 25%) were replaced with waste slag and silica fumes in mortars and concrete production. Detailed physical–mechanical characterization was performed on the mortar and concrete samples according to standard procedures. Test results indicated that the replacement of cement with slag and silica fumes reduces the physical and mechanical properties of mortar and concrete, but cement composites retained the required structural properties. If 15–20% is considered an acceptable level of compressive strength decrease, then it can be concluded that waste slag can be implemented in practice and be used as a construction material, with cement replacement in the maximal amount of 20% (17.8% of slag and 2.2% of silica fumes). On hardened mortar samples with maximal possible cement replacement (20%), physical–chemical characterizations were performed and included X-ray and infrared spectrophotometry, scanning electron microscopy, and thermal analysis. Results showed the absence of new phases and the presence of only those which were characteristic for starting samples, predominantly portlandite, quartz, calcite and calcium silicate-oxide.

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Effect of Waste Clay Brick Powder on Physical and Mechanical Properties of Cement Paste

The Open Civil Engineering Journal ◽

10.2174/1874149502115010370 ◽

2021 ◽

Vol 15 (1) ◽

pp. 370-380

Author(s):

David Sinkhonde ◽

Richard Ocharo Onchiri ◽

Walter Odhiambo Oyawa ◽

John Nyiro Mwero

Keyword(s):

Compressive Strength ◽

Cement Paste ◽

Setting Time ◽

Partial Replacement ◽

Clay Brick ◽

X Ray ◽

Cement Replacement ◽

Clay Bricks ◽

Brick Powder ◽

Scanning Electron

Background: Investigations on the use of waste clay brick powder in concrete have been extensively conducted, but the analysis of waste clay brick powder effects on cement paste is limited. Materials and Methods: This paper discusses the effects of waste clay brick powder on cement paste. Fragmented clay bricks were grounded in the laboratory using a ball mill and incorporated into cementitious mixes as partial replacement of Ordinary Portland Cement. Workability, consistency, setting time, density and compressive strength properties of paste mixes were investigated to better understand the impact of waste clay brick powder on the cementitious paste. Four cement replacement levels of 2.5%, 5%, 7.5% and 10% were evaluated in comparison with the control paste. The chemical and mineral compositions were evaluated using X-Ray Fluorescence and X-Ray Diffractometer, respectively. The morphology of cement and waste clay brick powder was examined using a scanning electron microscope. Results: The investigation of workability exhibited a reduction of slump attributed to the significant addition of waste clay brick powder into the cementitious mixes, and it was concluded that waste clay brick powder did not significantly influence the density of the mixes. In comparison with the control paste, increased values of consistency and setting time of cement paste containing waste clay brick powder confirmed the information available in the literature. Conclusion: Although waste clay brick powder decreased the compressive strength of cement paste, 5% partial cement replacement with waste clay brick powder was established as an optimum percentage for specimens containing waste clay brick powder following curing periods of 7 and 28 days. Findings of chemical composition, mineral composition and scanning electron microscopy of waste clay brick powder demonstrated that when finely ground, fragmented clay bricks can be used in concrete as a pozzolanic material.

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PROPERTIES OF FRESH POLYPROPYLENE FIBRE REINFORCED CONCRETE UNDER THE INFLUENCE OF POZZOLANS

Journal of Civil Engineering and Management ◽

10.3846/13923730.2003.10531339 ◽

2003 ◽

Vol 9 (4) ◽

pp. 271-279 ◽

Cited By ~ 2

Author(s):

Hau-yan Leung ◽

Ramapillai V. Balendran

Keyword(s):

Reinforced Concrete ◽

Fly Ash ◽

Silica Fume ◽

Setting Time ◽

Polypropylene Fibre ◽

Partial Replacement ◽

Fibre Reinforced Concrete ◽

Polypropylene Fibres ◽

Fibre Concrete ◽

Time Substitution

This paper summarises experimental results of some fresh concrete tests. Polypropylene fibres were added to the concrete mix to produce fibre reinforced concrete. Pozzolanic materials, including pulverised fly ash and silica fume, were used as partial replacement of cement, and their effects on the fresh fibre concrete were reported. Test results showed that the polypropylene fibre reduced the concrete workability significantly by thixotropic effect and decreased the setting time. Substitution of pozzolans also greatly affected the properties. The presence of fly ash increased the workability and setting time but in the presence of silica fume a reverse trend was observed. Empirical equations were proposed.

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Erratum to “Determination of ɑ/β phase boundaries and mechanical characterization of Mg-Sc binary alloys” [Mater. Sci. Eng. A 670 (2016) 335–341]

Materials Science and Engineering A ◽

10.1016/j.msea.2016.08.016 ◽

2016 ◽

Vol 674 ◽

pp. 713

Author(s):

Yukiko Ogawa ◽

Daisuke Ando ◽

Yuji Sutou ◽

Kyosuke Yoshimi ◽

Junichi Koike

Keyword(s):

Mechanical Characterization ◽

Binary Alloys ◽

Phase Boundaries ◽

Β Phase

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Mechanical, Electrical and Thermal Characterization of Commercially Available LTCC Dielectric Tapes

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.543.212 ◽

2013 ◽

Vol 543 ◽

pp. 212-215

Author(s):

Goran Radosavljević ◽

Nelu Blaž ◽

Andrea Marić ◽

W. Smetana ◽

Ljiljana Živanov

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Electrical Properties ◽

Material Characterization ◽

Mechanical Characterization ◽

Thermal Characterization ◽

Material Parameters ◽

Mechanical And Electrical Properties

Presented paper deals with mechanical and electrical properties of several commercially available LTCC (Low Temperature Co-fired Technology) tapes, as well as their thermal characterization. Three commercially available dielectric tape materials provided by Heraeus (CT700, CT707 and CT800) are investigated. The samples for determination of significant material parameters are prepared using the standard LTCC fabrication process. Results of the material characterization (chemical analysis, surface roughness electrical and mechanical properties) are presented. In addition thermo-electrical and-mechanical characterization of investigated tapes analysis is performed.

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Physical, chemical and mechanical characterization of Acrocarpus fraxinifolius cultivated in Sao Paulo

Maderas Ciencia y tecnología ◽

10.4067/s0718-221x2022000100409 ◽

2021 ◽

Vol 24 ◽

Author(s):

Karina A. de Oliveira ◽

Carolina A. Barros Oliveira ◽

Julio C. Molina

Keyword(s):

Mechanical Characterization ◽

Sao Paulo ◽

São Paulo ◽

Physical Chemical

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Environmental benefits of incorporating palm oil fuel ash in cement concrete and cement mortar

E3S Web of Conferences ◽

10.1051/e3sconf/202015803005 ◽

2020 ◽

Vol 158 ◽

pp. 03005 ◽

Cited By ~ 1

Author(s):

G.A. Jokhio ◽

H.M. Hamada ◽

A.M. Humada ◽

Y Gul ◽

Abid Abu-Tair

Keyword(s):

Palm Oil ◽

Cement Mortar ◽

Environmental Benefits ◽

Partial Replacement ◽

Cement Concrete ◽

Palm Oil Fuel Ash ◽

Cement Replacement ◽

Concrete Production ◽

Fuel Ash ◽

Oil Fuel

Palm oil fuel ash (POFA) is a by-product waste material from palm oil with many economic and environmental benefits. A lack of enough information on the advantages of POFA in the concrete production in various proportions was the main cause to carry out this work. This paper shows advantages of POFA as a partial replacement of cement in concrete production, especially cement mortar. The data collection has been done from the literature review related to the use of POFA as partial cement replacement in the production of cement concrete and mortar. Therefore, this paper can potentially become a guide for researchers and manufacturers to use POFA in various proportions to replace the ordinary Portland cement (OPC) in cement concrete and mortar. The positive and negative impact resulting from this material has been discussed carefully. This study recommends that researchers and academics should perform more experimental works in order to illustrate the desired benefits from POFA as cement replacement, thus mitigate the adverse environmental impacts of cement.

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A step towards sustainable glass fiber reinforced concrete utilizing silica fume and waste coconut shell aggregate

Scientific Reports ◽

10.1038/s41598-021-92228-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Osama Zaid ◽

Jawad Ahmad ◽

Muhammad Shahid Siddique ◽

Fahid Aslam ◽

Hisham Alabduljabbar ◽

...

Keyword(s):

Glass Fiber ◽

Silica Fume ◽

Glass Fibers ◽

Fiber Reinforced Concrete ◽

Coconut Shell ◽

Waste Materials ◽

Partial Replacement ◽

Sustainable Concrete ◽

Concrete Production ◽

The Impact

AbstractToday, it’s getting harder to find natural resources for concrete production. Utilization of the waste materials not just helps in getting them used in concrete, cement, and other construction materials, but also has various secondary advantages, for example, saving in energy, decrease in landfill cost, and protecting climate from pollution. Considering this in the development of modern structural design, utilizing waste materials instead of natural aggregate is a good option to make concrete that is sustainable and eco-friendly. The present research aims to find the impact of adding glass fiber into sustainable concrete made with silica fume, as a partial replacement of cement, and coconut shell added with different ratios as a replacement of coarse aggregate, on concrete mechanical and durability aspects. Various blends were made, with coconut shell as a substitution of coarse aggregates with different ratios. Portland cement was substituted with silica fume at 5%, 10%, 15%, and 20% by cement weight in all concrete blends. The volume ratios of glass fibers utilized in this study were 0.5%, 1.0%, 1.5% and 2.0%. Adding glass fibers increases concrete density to some extent and then marginally reduces the density of coconut shell concrete. When the percentage of glass fibers increases, the compressive, flexural and split tensile strength of coconut shell concrete also increases. From the lab results and SEM images of the present research display that glass fibers might be utilized in coconut shell concrete to enhance its mechanical and durability attributes, to accomplish sustainable concrete with acceptable strength with ease.

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Agricultural Solid Waste as Source of Supplementary Cementitious Materials in Developing Countries

Materials ◽

10.3390/ma12071112 ◽

2019 ◽

Vol 12 (7) ◽

pp. 1112 ◽

Cited By ~ 14

Author(s):

Suvash Chandra Paul ◽

Peter Mbewe ◽

Sih Kong ◽

Branko Šavija

Keyword(s):

Developing Countries ◽

Cementitious Materials ◽

Agricultural Wastes ◽

Cement Industry ◽

Supplementary Cementitious Materials ◽

Engineering Properties ◽

Partial Replacement ◽

Cement Production ◽

Cement Replacement ◽

Concrete Production

Concrete production utilizes cement as its major ingredient. Cement production is an important consumer of natural resources and energy. Furthermore, the cement industry is a significant CO2 producer. To reduce the environmental impact of concrete production, supplementary cementitious materials such as fly ash, blast furnace slag, and silica fume are commonly used as (partial) cement replacement materials. However, these materials are industrial by-products and their availability is expected to decrease in the future due to, e.g., closing of coal power plants. In addition, these materials are not available everywhere, for example, in developing countries. In these countries, industrial and agricultural wastes with pozzolanic behavior offer opportunities for use in concrete production. This paper summarizes the engineering properties of concrete produced using widespread agricultural wastes such as palm oil fuel ash, rice husk ash, sugarcane bagasse ash, and bamboo leaf ash. Research on cement replacement containing agricultural wastes has shown that there is great potential for their utilization as partial replacement for cement and aggregates in concrete production. When properly designed, concretes containing these wastes have similar or slightly better mechanical and durability properties compared to ordinary Portland cement (OPC) concrete. Thus, successful use of these wastes in concrete offers novel sustainable materials and contributes to greener construction as it reduces the amount of waste, while also minimizing the use of virgin raw materials for cement production. This paper will help the concrete industry choose relevant waste products and their optimum content for concrete production. Furthermore, this study identifies research gaps which may help researchers in further studying concrete based on agricultural waste materials.

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