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1
Folagbade, Samuel Olufemi. "Initial Surface Absorption of Cement Combination Concrete". Civil Engineering Dimension 20, nr 2 (8.10.2018): 96. http://dx.doi.org/10.9744/ced.20.2.96-101.
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This paper investigated the initial surface absorption (ISAT) of concrete using Portland cement (PC) and some binary and ternary cement combinations containing fly ash (FA), silica fume (SF) and metakaolin (MK) as partial replacements for PC at equal water/ cement ratios and strengths. At equal water/cement ratios, the cement combination concretes have higher ISAT values than PC concrete at 28 days and the disparity reduced with increasing curing age due to improved pozzolanic reactivity of the supplementary cementitious materials. SF and MK as binary and ternary cement components performed better than FA due to their higher fineness, improved particle packing and higher pozzolanic reactivity. At equal strengths, FA binary cement concretes have the lowest ISAT values and these reduced with increasing content of FA. At total replacement levels more than 20%, all the ternary cement concretes have lower ISAT values than PC concrete and the values reduced with increasing total replacement level due to the beneficial effect of FA.
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Al-Swaidani, A. M. "Production of more durable and sustainable concretes using volcanic scoria as cement replacement". Materiales de Construcción 67, nr 326 (10.03.2017): 118. http://dx.doi.org/10.3989/mc.2017.00716.
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The objective of the study is to investigate strength and durability-related properties of volcanic scoria-based cements. Compressive and tensile strength development of mortars and concretes containing volcanic scoria with replacement levels ranging from 10 to 35% was investigated. Water permeability, chloride penetrability and porosity of concretes cured for 2, 7, 28, 90 and 180 days were also examined. Results revealed that volcanic scoria could be suitable for making blended cements. The strength of mortar/concrete containing volcanic scoria was lower than that of plain cement mortar/concrete at all ages. However, at 90 day curing, the strengths of volcanic scoria-based mortars/concretes were comparable to those of plain cement. In addition, water permeability, chloride penetrability and porosity of scoria-based concretes were much lower than those of plain concrete. Further, the results were statistically analysed and estimation equations have been developed to predict the studied properties. SEM/EDX analysis was employed, as well.
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Anwar, Faiz Habib, Hilal El-Hassan, Mohamed Hamouda, Gilbert Hinge i Kim Hung Mo. "Meta-Analysis of the Performance of Pervious Concrete with Cement and Aggregate Replacements". Buildings 12, nr 4 (8.04.2022): 461. http://dx.doi.org/10.3390/buildings12040461.
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In recent years, pervious concrete (PC) has gained much attention as one of the strategies for low-impact development (LID) in pavements due to its structural, economic, and road-user benefits. This study sought to review and evaluate changes in the mechanical, hydraulic, and durability performance of PC produced with cement and aggregate replacements. A meta-analysis was conducted to elucidate the feasible range of the replacement percentage and the number of materials that could be used to replace cement and aggregates; single or binary replacements were considered. Results indicated that cement-replacing materials, industrial wastes (IWA), and recycled aggregates (RA) met the minimum requirement for the mechanical, hydraulic, and durability properties of PC. The use of a single cement replacement material provided PC with better performance than when cement was replaced with two or more materials or when cement alone was used. Industrial waste was found to be a better replacement to aggregates than RA. The combined replacement of cement and aggregates with IWA and other cement-replacing materials was the most effective method for improving the mechanical, hydraulic, and durability performance of PC. Replacements of up to 40% was considered viable for cement replacement, while up to 50% replacement was considered practical for aggregate and combined replacement. PC incorporating different cement-replacing materials exhibited equivalent or improved mechanical properties and maintained hydraulic performance compared to cement-based PC. Nonetheless, limited studies are available on the durability performance of PC made with cement and/or replacements. Thus, the durability of PC coupled with the applicability of replacement materials acquired from different locations need to be evaluated to address the viability of producing more durable PC with the use of replacements.
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Bunyamin, Bunyamin, i Amir Mukhlis. "Utilization of Oyster Shells as a Substitute Part of Cement and Fine Aggregate in the Compressive Strength of Concrete". Aceh International Journal of Science and Technology 9, nr 3 (30.12.2020): 150–56. http://dx.doi.org/10.13170/aijst.9.3.17761.
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The compressive strength of concrete depends on the physical characteristics of the concrete forming materials. Oyster shells originating from Krueng Neng, Aceh Besar are very abundant, left unattended by fishermen, causing pollution of the surrounding environment. Oyster shell dust contains CaO, which can be used as a partial substitution of cement. Therefore, it is necessary to study oyster shell ash as cement replacement and fine aggregate in concrete production. This research aims to determine the compressive strength of concrete using shell ash as cement replacement and fine aggregate. The oyster shells were obtained from Krueng Neng, Lamjamee Village, Jaya Baru, Aceh Besar District. The oyster shells were crushed with a Los Angeles Test machine and sieved with sieve size 2.36 mm for fine aggregate and sieve #200 for cement replacement. The water-cement ratios (w/c) were 0.4, 0.5 and 0.6. The results showed that concrete's compressive strength with 5% cement replacement level was higher than the concrete with cement only. Meanwhile, for other replacement levels, the compressive strengths of concrete specimens were lower than control specimens.
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Murugesh, V., Dr N. Balasundaram i Dr T. Senthil Vadivel. "Experimental Studies on Durability Studies of Concrete with Partial Replacement of Cement by Water Hyacinth Ash". International Journal of Engineering & Technology 7, nr 3.35 (2.09.2018): 22. http://dx.doi.org/10.14419/ijet.v7i3.35.29140.
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Cement is the main constituent ingredient in concrete. Now days many investigations undergone for substitute of cement due to green houses effect and global warming .Many new products like rice husk ash, egg shell powder, baggage ash, etc are used as an effluent replacement material for cement. The new and Practical material for substitute of cement is water hyacinth ash .Water hyacinth ash (WHA), is used as an effectual replacement of partial cement, and it has been proved in several characteristics of concrete. The main important parameters in concrete are strength, durability and workability. In this paper, 10 % of cement replaced by water hyacinth ash to investigate the effects of WHA on durability and Strength in concretes. On this basis, specimens were engrossed in water and acid to study the absorption property, acid attack and compared to conventional concrete. The test results show that replacement of cement by WHA in concrete has improved the parameters of concrete.
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Qadri, Muhammad Ahmed, Huzaifah Hameed i Osama Bhutta. "Fresh and Hardened Properties of Styrene Butadiene Rubber (SBR) Modified Concrete". European Journal of Engineering Research and Science 5, nr 4 (21.04.2020): 457–61. http://dx.doi.org/10.24018/ejers.2020.5.4.1883.
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The durability of concrete has been studied ever since it was first used. Researchers have incorporated several materials to make concrete strong and durable. This research focuses on the infusion of styrene butadiene rubber polymer (SBR) as a partial replacement of cement and studies its effects on fresh and hardened properties of concrete. Samples were prepared using partial replacement of SBR in proportions of 0%, 5%, 10% and 20%. Results showed that the fresh density of concrete decreased with the addition of SBR whereas the trends of workability showed an increase with cement replacement. Compressive strength increased at lower percentage replacements however the flexural and tensile strength increased till 15% SBR addition after which it decreased. The total porosity in terms of water absorption decreased which makes SBR modified concrete feasible for concretes exposed to moist conditions and the decreased porosity would increase its durability against chloride induced corrosion.
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Qadri, Muhammad Ahmed, Huzaifah Hameed i Osama Bhutta. "Fresh and Hardened Properties of Styrene Butadiene Rubber (SBR) Modified Concrete". European Journal of Engineering and Technology Research 5, nr 4 (21.04.2020): 457–61. http://dx.doi.org/10.24018/ejeng.2020.5.4.1883.
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The durability of concrete has been studied ever since it was first used. Researchers have incorporated several materials to make concrete strong and durable. This research focuses on the infusion of styrene butadiene rubber polymer (SBR) as a partial replacement of cement and studies its effects on fresh and hardened properties of concrete. Samples were prepared using partial replacement of SBR in proportions of 0%, 5%, 10% and 20%. Results showed that the fresh density of concrete decreased with the addition of SBR whereas the trends of workability showed an increase with cement replacement. Compressive strength increased at lower percentage replacements however the flexural and tensile strength increased till 15% SBR addition after which it decreased. The total porosity in terms of water absorption decreased which makes SBR modified concrete feasible for concretes exposed to moist conditions and the decreased porosity would increase its durability against chloride induced corrosion.
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Noor Azline, M. N., Farah Nora Aznieta Abd Aziz i Arafa Suleiman Juma. "Effect of Ground Granulated Blast Furnace Slag on Compressive Strength of POFA Blended Concrete". Applied Mechanics and Materials 802 (październik 2015): 142–48. http://dx.doi.org/10.4028/www.scientific.net/amm.802.142.
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The article reports a laboratory experimental programme that investigated effect of ground granulated blast furnace (GGBS) on compressive strength of POFA ternary concrete. Compressive strength tests were performed at a range of cements combinations, including 100%PC, two POFA levels for binary concrete, 35% and 45%, and 15%GGBS inclusion for POFA ternary concrete. The compressive strength results were examined in comparison to PC only and equivalent POFA binary concretes for up to 28 days. Results show that the reduction in compressive strength is greater with the higher cement replacement level for all concretes particularly for POFA binary concretes. However, 15%GGBS in POFA blended concrete has a comparable compressive strength compared to PC concrete at both, 35% and 45%, cement replacement levels except for ternary concrete at 0.65 w/c. In addition, the compressive strength of ternary concrete is slightly higher compared to binary concrete for all concrete combinations. Although there is no significant noticeable influence on strength development, the presence of GGBS did not adverse the strength development of POFA blended concrete. Thus, it can be concluded that GGBS compensates the adverse effect of POFA at early strength development.
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V. Sri Ramya Lekhini and Janardhan G. "Mechanical Properties on Self - Compacting Concrete Replacement with Fly Ash, Silica Fume in Cement and Addition with Fibres". International Journal for Modern Trends in Science and Technology 7, nr 03 (10.04.2021): 26–34. http://dx.doi.org/10.46501/ijmtst0703005.
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Self-compacting concrete has high workability and flow ability than normal compacted concrete. With its segregation resistance and fluidity, it offers a solution to problems in construction field like lack of skilled labour, inadequate compaction, over compaction, segregation etc. This study includes designing a self-compacting concrete mix which is standardized using its fresh properties with respect to EFNARC (European Federation of National Associations Representing for Concrete)standards. In this study, fly ash is used as partial replacement for cement in concrete. The mix design for M30 grade self-compacting concrete is done as per EFNARC standards. Then various properties of different mixes of M30 grade with 0%, 10%, 20%, 30%, 40% & 50%and 5% of silica fume as partial replacements of cement were compared, and the optimum percentage replacement is obtained at 30% replacement (SCC 30). On determining the optimum percentage replacement of fly ash in cement for M30 grade SCC as SCC 30, various properties such as weight loss and compressive strength and flexural strength of SCC 30 with normal SCC 30 are compared and then finally basalt fibres were added to cement content to asses the performance of concrete with fly ash and fibres as partial replacements of cement. It is found that the there is loss in weight as well as compressive strength and flexural strength of specimen due to adding fly ash and basalt fibres
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Kalinowska-Wichrowska, Katarzyna, Edyta Pawluczuk, Michał Bołtryk, Jose Ramón Jimenez, Jose Maria Fernandez-Rodriguez i David Suescum Morales. "The Performance of Concrete Made with Secondary Products—Recycled Coarse Aggregates, Recycled Cement Mortar, and Fly Ash–Slag Mix". Materials 15, nr 4 (15.02.2022): 1438. http://dx.doi.org/10.3390/ma15041438.
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The properties of cement concrete using waste materials—namely, recycled cement mortar, fly ash–slag, and recycled concrete aggregate—are presented. A treatment process for waste materials is proposed. Two research experiments were conducted. In the first, concretes were made with fly ash–slag mix (FAS) and recycled cement mortar (RCM) as additions. The most favorable content of the concrete additive in the form of RCM and FAS was determined experimentally, and their influence on the physical and mechanical properties of concrete was established. For this purpose, 10 test series were carried out according to the experimental plan. In the second study, concretes containing FAS–RCM and recycled concrete aggregate (RCA) as a 30% replacement of natural aggregate (NA) were prepared. The compressive strength, frost resistance, water absorption, volume density, thermal conductivity, and microstructure were researched. The test results show that the addition of FAS–RCM and RCA can produce composites with better physical and mechanical properties compared with concrete made only of natural raw materials and cement. The detailed results show that FAS–RCM can be a valuable substitute for cement and RCA as a replacement for natural aggregates. Compared with traditional cement concretes, concretes made of FAS, RCM, and RCA are characterized by a higher compressive strength: 7% higher in the case of 30% replacement of NA by RCA with the additional use of the innovative FAS–RCM additive as 30% of the cement mass.
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Sidabutar, Ros Anita, Johan Oberlyn Simanjuntak i Josua Marganda Simangunsong. "Pengaruh Penambahan Serat Ijuk Terhadap Kuat Tekan Beton". Jurnal Visi Eksakta 3, nr 1 (29.01.2022): 51–58. http://dx.doi.org/10.51622/eksakta.v3i1.570.
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Concrete is one of the construction materials consisting of a mixture of coarse aggregate and fine aggregate as a filling material, as well as cement and water as a binder. With the addition of fiber as a partial replacement of cement to obtain a cheaper cost, for simple buildings. With partial replacement of cement with fiber in normal concrete, which aims to determine the effect of partial replacement of cement with fiber against the compressive strength of concrete. By comparing the length variation of fibers which are respectively 4 cm, 6 cm, 8 cm and fibers taken 2% of the weight of cement. Where the calculation analysis (mix desing) using SNI 7656-2012 (procedure for making normal concrete mix plan). Mix design is done in order to determine the proportion of the mixture is done with strong concrete quality planned. The test object is a cylinder with a diameter with a diameter of 15 cm and height of 30 cm. From the results obtained the replacemen of some of the cement with fibers. Where the test results of normal concrete slump of 10 cm, fiber concrete measuring 4 cm by 10 cm, fiber conrete measuring 6 cm byy 9.8 cm and fiber concrete measuring 8 cm by 9.7 cm. And the maximum compressive strength test results obtained decreased, the test value of cylindrical concrete without the addition of fiber of 27.08 MPa, where the compressive strength of concrete by using 2% fibers with a length of 4 cm of 26.70 MPa, concrete fiber 6 cm of 25.94 MPa, and for fiber 8 cm of 24.72 MPa. So that the compressive strength of concrete that occurs decreases from normal concrete without the addition of fibers.
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Oyedepo, Olugbenga Joseph, Lekan Makanju Olanitori i Sumbo Philip Akande. "Performance of coconut shell ash and palm kernel shell ash as partial replacement for cement in concrete". Journal of Building Materials and Structures 2, nr 1 (30.01.2015): 18–24. http://dx.doi.org/10.34118/jbms.v2i1.16.
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High cost of cement used as binder in the production of concrete has led to a search for alternative. Using a mix design ratio of 1:2:4 and water binder ratio of 0.63, concrete cubes were casted using varying ordinary Portland cement (OPC): palm kernel shell ash (PKSA) and ordinary Portland cement (OPC): coconut shell ash (CSA) ratios of 100:0, 90:10, 80:20, 70:30 , 60:40 and 50:50 respectively. This research reveal that partial replacement of cement with 20% PKSA and CSA in concrete gives an average optimum compressive strength of 15.4 N/mm2 and 17.26 N/mm2 respectively at 28 days. While, the optimum value of compressive strength obtained at 28 days is 20.58 N/mm2 at 10% replacement with CSA. The value obtained is suitable for both light weight and heavy weight concrete respectively. Thus, the research show that the use of PKSA and CSA as a partial replacement for cement in concrete, at lower volume of replacement, will enhance the reduction of cement usage in concretes, thereby reducing the production cost and the environmental pollution caused by the dumping of the agricultural waste.
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Pavlů, Tereza, Vladimír Kočí i Magdaléna Šefflová. "Study Replacement of Cement with Recycled Cement Powder and the Environmental Assessment". Solid State Phenomena 249 (kwiecień 2016): 136–41. http://dx.doi.org/10.4028/www.scientific.net/ssp.249.136.
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This investigation is focused on possibility of partial cement replacement in concrete mixture and its environmental assessment. The cement in concrete mixture is replaced by recycled cement powder from modified construction and demolition (C&D) waste. Recycled cement powder were prepared in laboratory from C&D waste of high quality road concrete. The main goal of this investigation is optimize amount of recycled cement powder used as partial replacement of cement in concrete mixture according to mechanical, deformation and physical properties of concrete and environmental impact. The properties of the fine-aggregate concrete with partial replacement of cement by recycled cement powder were tested for this verification. The life cycle analysis was calculated for this optimization. The properties and environmental assessment of the fine-aggregate concrete with partial replacement of fine aggregate by fine recycled aggregate were examined for comparison.
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Kamau, Jhon, Ash Ahmed, Paul Hirst i Joseph Kangwa. "Performance of Class F Pulverised Fuel Ash and Ground Granulated Blast Furnace Slag in Ternary Concrete Mixes". European Journal of Engineering Research and Science 2, nr 6 (20.06.2017): 36. http://dx.doi.org/10.24018/ejers.2017.2.6.363.
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Cement is the most utilised material after water, and the processes that are involved in making it are energy intensive, contributing to about 7% of the total global anthropogenic carbon dioxide (CO2). Energy efficiency can however be achieved by using Supplementary Cementitious Materials (SCMs) such as Pulverised Fuel Ash (PFA) and Ground Granulated Blast Furnace Slag (GGBS) which demand less process heating and emit fewer levels of CO2. This work examined the advantages of substituting cement using PFA and GGBS in ternary (2 SCMs) concrete at steps of 0%, 5%, 7.5%, 10%, 15%, 20%, 25%, and 30%. It was found that PFA increased the workability of GGBS, whereas GGBS improved the strength of PFA. The densities of the resultant concrete were below those of the 0% replacement as well as those of individual binary (1 SCM) concretes. The tensile strengths of the ternary concrete were lower than those of the binary concretes, whereas the gains in compressive strengths over curing time were higher at lower replacements for the ternary concrete compared with the 0% replacement and the binary concretes, but lower at higher replacements. The findings indicate that PFA and GGBS could be used together to improve the properties of concrete where each falls short.
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Kamau, Jhon, Ash Ahmed, Paul Hirst i Joseph Kangwa. "Performance of Class F Pulverised Fuel Ash and Ground Granulated Blast Furnace Slag in Ternary Concrete Mixes". European Journal of Engineering and Technology Research 2, nr 6 (20.06.2017): 36–41. http://dx.doi.org/10.24018/ejeng.2017.2.6.363.
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Cement is the most utilised material after water, and the processes that are involved in making it are energy intensive, contributing to about 7% of the total global anthropogenic carbon dioxide (CO2). Energy efficiency can however be achieved by using Supplementary Cementitious Materials (SCMs) such as Pulverised Fuel Ash (PFA) and Ground Granulated Blast Furnace Slag (GGBS) which demand less process heating and emit fewer levels of CO2. This work examined the advantages of substituting cement using PFA and GGBS in ternary (2 SCMs) concrete at steps of 0%, 5%, 7.5%, 10%, 15%, 20%, 25%, and 30%. It was found that PFA increased the workability of GGBS, whereas GGBS improved the strength of PFA. The densities of the resultant concrete were below those of the 0% replacement as well as those of individual binary (1 SCM) concretes. The tensile strengths of the ternary concrete were lower than those of the binary concretes, whereas the gains in compressive strengths over curing time were higher at lower replacements for the ternary concrete compared with the 0% replacement and the binary concretes, but lower at higher replacements. The findings indicate that PFA and GGBS could be used together to improve the properties of concrete where each falls short.
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Golewski, Grzegorz Ludwik. "Combined Effect of Coal Fly Ash (CFA) and Nanosilica (nS) on the Strength Parameters and Microstructural Properties of Eco-Friendly Concrete". Energies 16, nr 1 (31.12.2022): 452. http://dx.doi.org/10.3390/en16010452.
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Disposal of the coal fly ash (CFA) generated from thermal power plants in huge quantities is one of the major concerns for the industry, as well as the natural environment. On the other hand, CFA can be used within a certain percentage range in the cement concrete mix as a replacement for cement. Nanomaterials can also be used to improve the properties of concrete. Therefore, this study investigated the effects of nanosilica (nS) on the mechanical parameters and microstructure of CFA cement concretes. This study utilized an nS content of 5%, along with three CFA contents, i.e., of 0, 15, and 25% by volume. Mechanical property tests and a thorough overview of changes in the structure of modified concrete were carried out to study the effect of the CFA content on the analyzed parameters of concrete containing nS. This study had the goal of elucidating the reinforcing mechanisms of CFA concrete by nS and providing design guidance for the practical engineering applications of CFA-nS composites. Based on the conducted studies, it was found that the combined usage of nS and CFA has synergistic and positive effects on improving mechanical parameters and microstructure in such concretes. The combined strengthening of a cement matrix by nS and CFA can fill the pores and microcracks in concrete composites and effectively improve the mechanical properties and microstructure of such materials. In this study, the optimal improvement was achieved when the concentration of additions was 5% nS and 15% CFA. The 28-day compressive strength and splitting tensile strength were increased by 37.68 and 36.21%, respectively, in comparison to control concrete. Tailored blended cements composed of nS and CFA content (up to 30% replacement level) can significantly improve the parameters of concrete composites, as well as reduce the carbon footprint of cement-based materials—constituting a step toward the production of eco-friendly concretes.
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Chi, Mao Chieh, Jen Hao Chi i Chung Hao Wu. "Effect of GGBFS on Compressive Strength and Durability of Concrete". Advanced Materials Research 1145 (marzec 2018): 22–26. http://dx.doi.org/10.4028/www.scientific.net/amr.1145.22.
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Facing the cement and concrete development process, reducing greenhouse gases and the consumption of natural resources has become an important issue. To reduce the cement content in concrete, the increased use of concrete combining large amounts of industrial by-products is expected. Ground granulated blast furnace slag (GGBFS) has been used as a supplementary cementitious material in ordinary Portland cement (OPC) concrete. In this study, GGBFS at different cement replacement ratios of 0%, 20%, 40%, and 60% by weight were used to produce concrete. Compressive strength test, water absorption, electrical resistivity, and rapid chloride penetration test (RCPT) were performed to investigate the effect of GGBFS on compressive strength and durability of concrete. Test results show that GGBFS concrete with 40% cement replacement (G40) has the highest compressive strength. The water absorption and chloride permeability reduced with the increasing cement replacement percentage by GGBFS. Meanwhile, the electrical resistivity increased with an increasing GGBFS replacement percentage. Based on the results, GGBFS concrete with 40% cement replacement seems to be the optimum replacement in this study.
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Al-Anbori, Zena K. Abbas, i Ahmed A. Ibrahim Al-Obaidi. "Some Mechanical Properties of Concrete by using Manufactured Blended Cement with Grinded Local Rocks". Journal of Engineering 22, nr 3 (1.03.2016): 1–21. http://dx.doi.org/10.31026/j.eng.2016.03.01.
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The use of blended cement in concrete provides economic, energy savings, and ecological benefits, and also provides. Improvement in the properties of materials incorporating blended cements. The major aim of this investigation is to develop blended cement technology using grinded local rocks . The research includes information on constituent materials, manufacturing processes and performance characteristics of blended cements made with replacement (10 and 20) % of grinded local rocks (limestone, quartzite and porcelinite) from cement.
The main conclusion of this study was that all types of manufactured blended cement conformed to the specification according to ASTM C595-12 (chemical and physical requirements). The percentage of the compressive strength for blended cement with 10% replacement are (20, 11 and 5) % , (2 , 12 and, 13) % and (18, 15 and 16) % for limestone , quartzite and porcelinite respectively at (7,28 and 90)days for each compare to the reference mix, while blended cement with 20% replacement are (-3, -5 and -11) ,(6, -4% and -5) and (6, 4 and 6) % for limestone , quartzite and porcelinite respectively at (7, 28 and 90)days compare to the reference mix .The other mechanical properties (flexural tensile strength and splitting tensile strength) are the same phenomena of increase and decrease in compressive strength. The results indicated that the manufacture Portland-limestone cement, Portland-quartzite cement and Portland-porcelinite cement with 10% replacement of cement with improvable mechanical properties while the manufacture Portland-porcelinite cement with 20% replacement of cement with slight improvable mechanical properties and more economical cost.
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Pavlů, Tereza, i Magdaléna Šefflová. "Non Destructive Testing of Concrete with Recycled Cement Powder". Applied Mechanics and Materials 825 (luty 2016): 45–48. http://dx.doi.org/10.4028/www.scientific.net/amm.825.45.
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This study deals with determination of the physical properties of fine-aggregate concrete with partial replacement of cement in concrete mixture. Cement was replaced by recycled cement powder originating from construction and demolition waste. The main goal of this study is evaluation of the basic physical properties of the fine-aggregate concrete with partial cement replacement by recycled concrete powder such as density, water absorption capacity and capillary water absorption. The fine recycled concrete which was used as partial replacement of cement had the same grain size as cement. The replacement rate was 0 %, 5 %, 10 % and 15 %. Physical properties were investigated by using cubic and prismatic specimens.
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Folagbade, Samuel Olufemi, i Aluko Olawale. "Permeation Resistance of Sawdust Ash Blended Cement Laterized Concrete". Civil Engineering Dimension 21, nr 2 (18.10.2019): 76–83. http://dx.doi.org/10.9744/ced.21.2.76-83.
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This paper compared the initial surface absorption of conventional concrete and laterized concrete containing Portland cement (PC) and sawdust ash (SDA). Laterized concrete was produced at laterite contents of 15 and 30% as partial replacement for sand and SDA contents of 10 and 20% as partial replacement for PC. Compressive strengths at 28 days and initial surface absorption after 10 minutes (ISA-10) at 28, 60 and 90 days were determined at the water/cement ratios of 0.35, 0.50 and 0.65 and assessed at equal 28-day strengths of 25-35 N/mm2. At equal water/cement ratios, compressive strength reduced and ISA-10 increased with increasing content of laterite and SDA. On the other hand, compressive strength and resistance to surface absorption of the blended cement laterized concretes increased with increasing curing age. At equal strengths, all the blended cement laterized concretes have better resistance to surface absorption than the conventional PC concrete.
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Alam, Jamshed. "Strength Determination of High Strength Concrete Blended with Copper Slag and Fly Ash". International Journal for Research in Applied Science and Engineering Technology 9, nr VII (15.07.2021): 1198–203. http://dx.doi.org/10.22214/ijraset.2021.36515.
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An experimental analysis was conducted to study the effects of using copper slag as a fine aggregate (FA) and the effect of fly ash as partial replacement of cement on the properties high strength concrete. In this analysis total ten concrete mixtures were prepared, out of which five mixes containing different proportions of copper slag ranging from 0% (for the control mix) to 75% were prepared and remaining five mixes containing fly ash as partial replacement of cement ranging from 6% to 30% (all mixes contains 50% copper slag as sand replacements). Concrete matrix were tested for compressive strength, tensile strength and flexural strength tests. Addition of copper slag as sand replacement up to 50% yielded comparable strength with that of the control matrix. However, further additions of copper slag, caused reduction in strength due to an increment of the free water content in the mix. Concrete mix with 75% copper slag replacement gave the lowest compressive strength value of approximately 80 MPa at 28 days curing period, which is almost 4% more than the strength of the control mix. For this concrete containing 50% copper slag, fly ash is introduced in the concrete to achieve the better compressive, split and flexural strengths. It was also observed that, introduction of the fly ash gave better results than concrete containing 50% copper slag. When concrete prepared with 18 % of fly ash, the strength has increased approximately 4%, and strength decreased with further replacements of the cement with fly ash. Hence, it is suggested that 50% of copper slag can be used as replacement of sand and 18% fly ash can be used as replacement of cement in order to obtain high strength concrete.
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Verma, Nitin, i Balwinder Singh. "Experimental analysis of basic mechanical properties of concrete upon replacement with silica fume and steel slag". IOP Conference Series: Earth and Environmental Science 889, nr 1 (1.11.2021): 012021. http://dx.doi.org/10.1088/1755-1315/889/1/012021.
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Abstract The prime aim in this paper is to find out the effect of Silica Fume and Steel Slag replacements for cement and fine aggregate respectively in the concrete matrix. The research included replacement of constant percentage of silica fume i.e. 10% with cement and varying percentages of steel slag replacements viz. 40%, 45%, 50% and 55% with fine aggregates. It was found from the experimental investigations that optimum results for strength in compression, flexure and split case for concrete were established on 10% of silica fume replacement for steel slag and 50% replacement of steel slag with sand.
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Al-Gahtani, Khalid, Ibrahim Alsulaihi, Mohamed Ali i Mohamed Marzouk. "Production of green concrete using recycled waste aggregate and byproducts". Built Environment Project and Asset Management 7, nr 4 (14.09.2017): 413–25. http://dx.doi.org/10.1108/bepam-09-2016-0047.
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Purpose The purpose of this paper is to highlight the sustainability benefits of using demolition and industrial wastes as a replacement for aggregates and cement in traditional concrete mixes. Design/methodology/approach Crushed concrete from demolition sites served as a replacement for fine and coarse aggregate in some of the mixes at various ratios. In addition, ground granulated blast furnace slag, metakaolin, silica fume, and fly ash each served as a cement replacement for cement content in the mixes tested in this research at various rates. Compression strength tests, permeability, and thermal expansion tests were performed on various mixes to compare their performance to that of traditional mixes with natural aggregate, and with no cement replacement. Findings The compressive strength results indicated the suitability of using such demolition wastes as replacements in producing green concrete (GC) without hindering its mechanical characteristics significantly. In addition, the results indicated an enhancement in the mechanical characteristics of GC when replacing cement with pozzolanic industrial wastes and byproducts. Originality/value The research assesses the utilization of sustainable GC using recycled waste aggregate and byproducts.
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Rekha, K., i R. Thenmozhi. "Evaluation of Mechanical Properties of BAGcrete". Advanced Materials Research 984-985 (lipiec 2014): 693–97. http://dx.doi.org/10.4028/www.scientific.net/amr.984-985.693.
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The usage of waste materials in making concrete gives a satisfactory solution to some of the problems related to waste management and environmental concerns. In the development of blended cements, some of the Agro wastes such as sugarcane bagasse ash, rice husk ash and wheat straw ash are used as pozzolanic materials. Few studies have been reported on the use of bagasse ash (BA) as partial cement replacement material. This research aims to study the physical and mechanical properties of hardened concrete prepared with bagasse ash as partial replacement material for cement are reported. The Portland cement was replaced with BA in the ratio of 0%, 5%, 10%, 15% and 20% of weight of cement. The compressive strength, splitting tensile strength and flexural strength of concrete at the age of 28 days were investigated. From the test results it was observed that bagasse ash is an effective mineral admixture, with 5% as optimal replacement ratio of cement.
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Oviedo, Ignacio, Mauricio Pradena, Óscar Link i José T. Balbo. "Using Natural Pozzolans to Partially Replace Cement in Pervious Concretes: A Sustainable Alternative?" Sustainability 14, nr 21 (29.10.2022): 14122. http://dx.doi.org/10.3390/su142114122.
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Concrete is one of the most widely used construction materials all around the globe. Associated with urban expansion, concrete pavements increase the impermeable surfaces that affect the hydrological cycle and generate urban heat islands. Cement is one of the main components of concrete, and its production is one of the main sources of worldwide CO2 emissions. Pervious concrete with partial cement replacement represents a more sustainable alternative. In this paper, the use of natural pozzolans zeolite and pumicite, as partial cement replacement materials in pervious concrete mixtures, is analyzed. The mechanical and hydraulic properties of pervious concretes using different percentages of pumicite and zeolite to replace cement (0% to 20%) were evaluated by a series of tests on compressive strength, flexural strength, permeability, porosity, and a microanalysis by SEM for the samples. Additionally, experiments with a plasticizer additive were conducted. The results show that mixtures with 0.35 W/C ratio present better mechanical and hydraulic properties; pumicite shows a better performance than zeolite, with the better properties achieved at 10% cement replacement; and the addition of plasticizer increased the final strengths. It is recommended to partially replace cement by adding 10% pumicite and to consider using 0.7% of plasticizer.
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Jatoi, Masroor Ali, Ghulam Shabir Solangi, Fahad Ali Shaikh, Sarosh Khan i Shabir Ahmed. "Effect of Lakhra Fly Ash as Partial Replacement of Cement in Traditional Concrete". Mehran University Research Journal of Engineering and Technology 38, nr 4 (1.10.2019): 1045–56. http://dx.doi.org/10.22581/muet1982.1904.16.
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This study was aimed to determine the effect of LFA (Lakhra Fly Ash) as partial replacement of cement in concrete. To conduct this study, a total of 72 standard concrete cylinders were cast with 1:2:4 proportions at 0.5 water-binder ratios. Cement was partially replaced by weight with LFA and the percentage replacements of FA (Fly Ash) were kept as 0, 5, 15, 25, 40 and 50%. In addition to that, workability of each mix was determined by Slump Cone test and Compaction Factor test. Out of 72 cylinders, 36 cylinders were tested to determine the compressive strength while the remaining 36 cylinders were tested to determine the tensile strength of concrete, at 7 days curing period, by using UTM (Universal Testing Machine). The results revealed that 25% replacement of binder with LFA, determined an increase in compressive strength of concrete up to 15% as compared to normal cement concrete. Moreover, the tensile strength of concrete also increased up to 16% for the same percentage replacement. Furthermore, it also increased the workability, cohesiveness and surface finishes of concrete. This finding can help to reduce the admixture dosage or the water content of the mix. On the contrary, the compressive strength as well as the tensile strength of concrete decreased in case of 40 and 50% replacements of the cement with FA.
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Ogrodnik, Paweł, i Jacek Szulej. "Structural steel bond to concrete with waste aggregate". SHS Web of Conferences 57 (2018): 02007. http://dx.doi.org/10.1051/shsconf/20185702007.
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The article presents the results of bond tests of B500SP structural steel to concretes subjected to thermal stress. Concretes were designed purely on the basis on waste aggregate made of soft clay pottery with using two types of cements: Portland CEM 32.5R and aluminous cement Górkal 70. In the research was used the method of direct pulling the steel rod out of the concrete cover (Pullout Test). For the tests were prepared four types of concretes: two bases of aluminous cement and two on Portland cement without additions. In the remaining mixtures containing the additive in the form of clinoptilolite, the method of simple weight replacement of the selected type of cement with clinoptilolite in the amount of 10% was used. Mineral puzzolana additives are intended to modify the phase composition of hardened cement slurry towards reducing the portlandite and changing the CaO/SiO2 ratio in the C-S-H phase. The results of the tests confirmed that the bond of the selected steel type to concrete on the recycle aggregate does not differ from the results achieved with natural aggregate. It was also confirmed that addition of clinoptilolite to concrete with Portland cement has beneficial effect when it is subjected to thermal stress.
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Powar, Namrata Shankar. "Corrosion of Reinforcement in HVFA Concrete". International Journal for Research in Applied Science and Engineering Technology 10, nr 10 (31.10.2022): 1356–70. http://dx.doi.org/10.22214/ijraset.2022.47174.
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bstract: Concrete is a composite material composed of fine aggregate and coarse aggregate bonded together with cement that hardens over time. Concrete is one of the most frequently used building materials. Water cement ratio plays an important role which influences various properties such as workability, strength and durability. In concrete cement is main concrete material.The use of fly ash as an addictive material, as replacement of cement. The most important benefit is reduced permeability to water and chemicals. Properly cured concrete made with fly ash creates a denser product because the size of pores is reduced. This increases strength and reduces permeability and corrosion. For concrete mixes 43 grade of ordinary Portland cement and class F type Fly ash is concrete cubes are casted with varying percentage of fly ash and ultrafine fly ash. Three types of percentage is used as replacement of cement with fly ash. For replacement 40% ,50% and 60% fly ash is used. The size of cubes is 150mm x 150mm x150mm.Water/cement ratio 0.36 and Four types of percentage of Ultra fine fly ash is added such as 6%,8%,10% and 12%. Test is carried out after 7 days and 28 days of curing period. The tests conducted on concrete specimens are compressive strength. Results show that the addition of 6 wt.% UFFA significantly improved the early age and later age compressive strengths of HVFA concretes. The HVFA concrete containing 50% fly ash and 6% UFFA exhibited higher corrosion resistance properties. The results also indicate the effectiveness of UFFA in producing high packing density and in accelerating the pozzolanic activity to produce more C–S–H gel by consuming calcium hydroxide (CH) in HVFA concretes.
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Pavlů, Tereza, Magdaléna Šefflová i Vladimír Hujer. "The Properties of Fine-Aggregate Concrete with Recycled Cement Powder". Key Engineering Materials 677 (styczeń 2016): 292–97. http://dx.doi.org/10.4028/www.scientific.net/kem.677.292.
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The main aim of this contribution is verification of properties of concrete with partial replacement of cement by recycled cement powder originating from waste concrete. The main topic of this article is the study of influence of partial replacement of cement by recycled cement powder (RCP) to the cement paste properties, workability of fresh concrete and strength development and dynamic modulus of elasticity of fine aggregate concrete with partial replacement of cement. The workability of fresh concrete were tested by flow table test. The compressive strength, tensile strength in bending and dynamic modulus of elasticity were tested at the age 7, 14, 28 and 90 days. Partial replacement of cement was 0, 5, 10 and 15 % for all these tests. Mechanical properties were investigated by using cubic and prismatic specimens. The determination of the initial setting time of cement paste were measured by automatic Vicat apparatus for replacement rate of cement 0, 5, 10, 15 and 25 %.
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Zhao, Jun, Eskinder Desta Shumuye, Zike Wang i Gashaw Assefa Bezabih. "Performance of GGBS Cement Concrete under Natural Carbonation and Accelerated Carbonation Exposure". Journal of Engineering 2021 (27.03.2021): 1–16. http://dx.doi.org/10.1155/2021/6659768.
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One of the primary problems related to reinforced concrete structures is carbonation of concrete. In many cases, depth of carbonation on reinforced concrete structures is used to evaluate concrete service life. Factors that can substantially affect carbonation resistance of concrete are temperature, relative humidity, cement composition, concentration of external aggressive agents, quality of concrete, and depth of concrete cover. This paper investigates the effect of varying the proportions of blended Portland cement (ordinary Portland cement (OPC) and ground granulated blast-furnace slag (GGBS)) on mechanical and microstructural properties of concrete exposed to two different CO2 exposure conditions. Concrete cubes cast with OPC, and various percentages of GGBS (0%, 30%, 50%, and 70%) were subjected to natural (indoor) and accelerated carbonation exposure. The aim of this paper is to present the research findings and authenticate the literature results of carbonation by using GGBS cement in partial replacement of OPC. The concretes with OPC are compared to concretes with various percentages of GGBS, to assess the carbonation depth as well as rate of carbonation of GGBS-based concretes, under both accelerated carbonation and natural carbonation exposure conditions. Even though GGBS cement increases the carbonation depth, the results are not the same with different GGBS replacement percentages. A correlation is made between concrete samples exposed to 15 ± 2% carbon dioxide (CO2) concentration and those exposed to natural CO2 concentration. The results reveal that the products formed by carbonation are similar under both exposure conditions. The experimental tests also revealed that GGBS cement concrete has a lower carbonation resistance than OPC concrete, due to the consumption of portlandite by the pozzolanic reaction. The combination of 70% OPC and 30% GGBS behaved well enough with respect to accelerated carbonation exposure, the depth of carbonation being roughly equivalent to that of control group (100% OPC). The results also show that rate of carbonation becomes more sensitive as the percentage of GGBS replacement increases (binder ratio), rather than duration of curing. Concretes exposed to natural carbonation (indoor) achieved lower carbonation rates than those exposed to accelerated carbonation.
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Olutoge, F. A., H. A. Quadri i O. S. Olafusi. "Investigation of the Strength Properties of Palm Kernel Shell Ash Concrete". Engineering, Technology & Applied Science Research 2, nr 6 (4.12.2012): 315–19. http://dx.doi.org/10.48084/etasr.238.
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Many researchers have studied the use of agro-waste ashes as constituents in concrete. These agro-waste ashes are siliceous or aluminosiliceous materials that, in finely divided form and in the presence of moisture, chemically react with the calcium hydroxide released by the hydration of Portland cement to form calcium silicate hydrate and other cementitious compounds. Palm kernel shell ash (PKSA) is a by-product in palm oil mills. This ash has pozzolanic properties that enables it as a partial replacement for cement but also plays an important role in the strength and durability of concrete. The use of palm kernel shell ash (PKSA) as a partial replacement for cement in concrete is investigated. The objective of this paper is to alleviate the increasing challenges of scarcity and high cost of construction materials used by the construction industry in Nigeria and Africa in general, by reducing the volume of cement usage in concrete works. Collected PKSA was dried and sieved through a 45um sieve. The fineness of the PKSA was checked by sieving through 45um sieve. The chemical properties of the ash are examined whereas physical and mechanical properties of varying percentage of PKSA cement concrete and 100% cement concrete of mix 1:2:4 and 0.5 water-cement ratios are examined and compared. A total of 72 concrete cubes of size 150 × 150 × 150 mm³ with different volume percentages of PKSA to Portland cement in the order 0:100, 10:90 and 30:70 and mix ratio of 1:2:4 were cast and their physical and mechanical properties were tested at 7, 14, 21 and 28 days time. Although the compressive strength of PKSA concrete did not exceed that of OPC, compressive strength tests showed that 10% of the PKSA in replacement for cement was 22.8 N/mm2 at 28 days; which was quite satisfactory with no compromise in compressive strength requirements for concrete mix ratios 1:2:4. This research showed that the use of PKSA as a partial replacement for cement in concrete, at lower volume of replacement, will enhance the reduction of cement usage in concretes, thereby reducing the production cost. This research was carried out at the University of Ibadan, Ibadan, Nigeria.
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Abebaw, Gashaw, Bahiru Bewket i Shumet Getahun. "Experimental Investigation on Effect of Partial Replacement of Cement with Bamboo Leaf Ash on Concrete Property". Advances in Civil Engineering 2021 (28.12.2021): 1–9. http://dx.doi.org/10.1155/2021/6468444.
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Ethiopia’s construction industry is aggressively expanding than ever before. Cement is the most essential and expensive material in this regard. Cement takes 10%–15% by volume of concrete. Nowadays, the construction industry is challenged by the scarcity of cement and price escalation of the cement market. However, scholars try to replace cement with pozzolanic material. Besides this, they investigated that bamboo leaf ash possesses pozzolanic properties. Ethiopia has about 850,000 hectares of lowland bamboo, so it is good to utilize bamboo leaf ash as a replacement material for cement. In this study, the capability of lowland Ethiopian bamboo leaf ash as a partial substitute for cement in C-25 concrete production with 0%, 5%, 10%, 15%, and 20% replacement of OPC by BLA with 0.49 percent water-to-cement ratio was investigated. This study examines the chemical properties of BLA, physical properties of cement paste, workability, compressive strength, water absorption, density, and sulfate attack of concrete. The chemical composition of bamboo leaf ash was examined, the summation of SiO2, AlO3, and FeO3 is 76.35%, and the ash was classified class N pozzolan. The normal consistency percentage of water increases as the BLA replacement amount increases, and both initial and final setting time ranges increase as the BLA replacement amount increases. The compressive strength of concrete for 5% and 10% BLA achieves the target mean strength (33.5 MPa) on the 28th day, and on the 56th day, 5% and 10% replacements increase the concrete strength by 1.84% and 0.12%, respectively. The water absorption and sulfate attack have significant improvement of the BLA-blended concrete on 5% and 10% BLA content. According to the findings, bamboo leaf ash potentially substitutes cement up to 10%. The outcome of the study will balance the cement price escalation and increase housing affordability without compromise in quality.
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Topič, Jaroslav, Josef Fládr i Zdeněk Prošek. "Flexural and Compressive Strength of the Cement Paste with Recycled Concrete Powder". Advanced Materials Research 1144 (marzec 2017): 65–69. http://dx.doi.org/10.4028/www.scientific.net/amr.1144.65.
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In previous work focused on using recycled concrete powder as cement replacement the basic dependency of the mechanical properties on the amount of recycled concrete powder was defined. Influence of the amount of recycled concrete powder on the flexural and compressive strength was shown on 0, 33, 67 and 100 wt. % cement replacement. Based on the previous data the strength properties of the cement paste with recycled concrete powder below 33 wt. % was almost constant and strength properties were comparable with reference sample made of cement only. After the recycled concrete powder in cement paste exceeded amount of 33 wt. % the flexural and compressive strength decrease rapidly. In case of 67 wt. % amount of recycled concrete powder the compressive strength decrease about 65 %. The aim of this article is define critical amount of recycled concrete powder in cement paste when strength properties start decrease rapidly and cement replacement is no longer beneficial. This critical amount will be located somewhere between 30 and 50 wt. % of recycled concrete powder. Replacement below critical amount could lead to cost reduction of cement composites and also the negative impact of the cement production and concrete disposal on environmental could be reduced.
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Rahul, R., Dr R. Chithra i Dr R. Thenmozhi. "Experimental Investigation on Reactive Powder Concrete by Partial Replacement of Cement with Different Pozzolanic Materials". International Journal for Research in Applied Science and Engineering Technology 11, nr 6 (30.06.2023): 2292–98. http://dx.doi.org/10.22214/ijraset.2023.54041.
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Abstract: Reactive powder concrete (RPC) is one of the ultra-high performance concrete (UHPC). In RPC the coarse aggregate is eliminated and the micro particles like silica fume, quartz powder and sand are utilized in the production process. The high cement content and low water to binder ratio in RPC lead to shrinkage problems. Hence in this study, an attempt is made to produce eco-friendly RPC by replacing cement with 3 different pozzolanic materials from industrial wastes such as Fly ash, GGBS and Granite powder. To assess the viability of partial replacement of cement by pozzolanic materials, nine mixes have been arrived with 10%, 20% and 30% replacements. The fresh concrete property such as slump and the compressive strength are determined for all the mixes. By comparing the strength property the suitable alternate replacement material and replacement percentage for cement in RPC is found out
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Santos, Humberto Mycael Mota, Lidiane Fernanda Jochem, Paulo Ricardo de Matos, Cézar Augusto Casagrande, Érika Pinto Marinho, Maciej Szeląg i Ana Cecília Vieira de Nóbrega. "Porcelain Tile Polishing Residue in Concrete as an Additive or Replacement for Portland Cement". Applied Sciences 13, nr 5 (22.02.2023): 2824. http://dx.doi.org/10.3390/app13052824.
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In this study, 10–50% of porcelain tile polishing residue (PPR) was used as an additive or as partial replacement of cement in concrete. The cement consumption was kept constant by correcting the amount of sand for each mixture. Concrete workability (slump) was reduced by up to 88.72% when PPR replaced the cement by up to 30%, while it was reduced by only 4.10% when PPR was added to the concrete at the same levels. Compressive strength at 28 days increased up to 92.22% with 50% PPR as additive, reducing the equivalent emission of CO2 per m³ of concrete up to 38.18%. PPR incorporation reduced the water permeability of concrete by up to 30.70% and 17.54% when used in addition and in cement replacement, respectively. Overall, PPR as an additive up to 50% and in cement with substitution levels up to 10–40% presented themselves as viable solutions for developing more resistant and durable concretes than the reference mixture (without incorporation of PPR).
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Silva, M. G., M. R. M. Saade i V. Gomes. "Influence of service life, strength and cement type on life cycle environmental performance of concrete". Revista IBRACON de Estruturas e Materiais 6, nr 6 (grudzień 2013): 844–53. http://dx.doi.org/10.1590/s1983-41952013000600002.
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This paper assesses environmental loads of concretes made with Portland blended cements containing different proportions of ground granulated blast furnace slag (ggbs) as clinker replacement and with characteristic compressive strength ranging from 25 to 60 MPa. Impact assessment method CML 2001 v. 2.04 and Life Cycle Assessment platform SimaPro 7.3 respectively supported calculations in terms of environmental impact categories and of a set of life cycle indicators. Service life, estimated via Life 365 v.2.1 software, is tested as a functional unit normalizer for environmental assessment of concrete elements through application to the embodied CO2 indicator. Increased fractions of ggbs in Portland cement reduce concretes' life cycle environmental loads as indicated by all metrics but blue water footprint. Effects of clinker replacement on the indicators are discussed. Service life consideration proved to add coherence to concrete's environmental, functional and technical quality interpretation.
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Pavlů, Tereza, i Magdaléna Šefflová. "The Development of the Fine-Aggregate Concrete Strength with Recycled Cement Powder". Applied Mechanics and Materials 827 (luty 2016): 255–58. http://dx.doi.org/10.4028/www.scientific.net/amm.827.255.
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This investigation was focused on possibility of use recycled cement powder originating from the construction and demolition concrete waste as partial replacement of cement in concrete mixture. The main goal of this paper is the study of the mechanical properties development of the fine-aggregate concrete with partial cement replacement at the age 7, 14 and 28 days. The compressive strength and dynamic modulus of elasticity were tested in time. The recycled cement powder from fine recycled concrete, which was used as partial replacement of cement, had the same grain size as cement. The concrete mixtures contained 95 %, 90 % and 85 % of cement and residue has been replaced by recycled cement powder. Mechanical properties were tested on cubic and prismatic specimens.
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PASHTOON, Muhammad Israr, Shafi Ullah MİAKHİL i Mohammad Mukhlis BEHSOODİ. "Waste Glass “An Alternative of Cement and Fine Aggregate in Concreteˮ". International Journal of Engineering Technologies IJET 8, nr 2 (13.07.2023): 70–76. http://dx.doi.org/10.19072/ijet.1143637.
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The major aim of this study is to use Waste Glass Powder (WGP) which is obtained from grinding glass waste using an abrasion apparatus, as cement and a fine aggregate substitute in concrete. The physical and mechanical characteristics, workability, and compressive strength of concrete were studied by using WGP as cement and fine aggregate replacement simultaneously. In order to perform correctly, the glass has to be sieved to particle sizes of less than 150 µm sieve for cement replacement and 4.75 mm for fine aggregate replacement. WGP was used to replace the cement and fine aggregate in concrete, yielding products with respective cement contents of 10.0% and 15% and fine aggregate contents of 15.0% and 20%, and the properties of this concrete have been compared with reference specimens with zero replacement. Cube specimens were cast, cured, and tested for compressive strength and workability at 7, 14, 28, and 56 days of age, and the results were then compared to those of traditional concrete. The use of WGP as a cement and fine aggregate substitute resulted in a reduction in concrete's compressive strength and workability. However, the findings revealed that WGP could be used as a partial substitute for cement and fine aggregates, with 10 to 15% of cement and fine aggregate substitution by WGP being the optimum in terms of strength and economy. As a result, we can utilize it in structures that are moderately heavy.
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Chandra Paul, Suvash, Peter Mbewe, Sih Kong i Branko Šavija. "Agricultural Solid Waste as Source of Supplementary Cementitious Materials in Developing Countries". Materials 12, nr 7 (3.04.2019): 1112. http://dx.doi.org/10.3390/ma12071112.
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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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Butler, Liam, Jeffrey S. West i Susan L. Tighe. "Effect of Recycled Concrete Aggregate Properties on Mixture Proportions of Structural Concrete". Transportation Research Record: Journal of the Transportation Research Board 2290, nr 1 (styczeń 2012): 105–14. http://dx.doi.org/10.3141/2290-14.
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This study focuses on characterizing several recycled concrete aggregate (RCA) sources, developing concrete mixture proportions that incorporate RCA as coarse aggregate, and investigating the effect of coarse aggregate properties on the main mixture proportion parameters [i.e., cement content, water demand, and water–cement (w/c) ratio]. Four aggregate types were investigated: one control virgin aggregate source and three RCAs produced from the crushing of hardened concrete. Numerous aggregate tests, including density, absorption, abrasion resistance, adhered mortar content, and crushing value, were performed. Fourteen mixture proportions were developed with the use of three mixture proportion scenarios (control, direct replacement, and strength based) and two compressive strength levels (40 and 60 MPa). The effect of RCA on compressive strength and workability was evaluated by replacement of natural coarse aggregate with RCA. Contrary to numerous studies, one of the RCA concretes (RCA-1) had compressive strengths up to 12% higher than the equivalent control mixture. Mixture proportions (water, cement, and w/c ratio) were later adjusted to ensure that the RCA concretes had compressive strength and slump values similar to the control concretes. Variations in water demand, cement content, and w/c ratio could then be directly attributed to the properties of the RCA source. RCA-1 concrete required less cement (and a higher w/c ratio) to achieve strengths and slumps similar to the control concrete. The findings and recommendations of this research will assist concrete producers, engineers, and field technicians involved in the selection of RCA sources in developing mixture proportions for structural-grade RCA concrete.
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Vimalanathan, M. "Partial Replacement of Cement by Baryte". International Journal for Research in Applied Science and Engineering Technology 10, nr 6 (30.06.2022): 4527–30. http://dx.doi.org/10.22214/ijraset.2022.44817.
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Abstract: The use of high volume baryte concrete fits in very well with sustainable development. High performance concrete is being widely used all over the world. High volume baryte concrete mixtures contain lower quantities of cement and higher volume of baryte (up to 40%). The use of baryte concrete at proportions ranging from 0 to 40% of total cementations binder has been studied extensively over the last twenty years and the properties of blended concrete are well documented. The replacement of baryte as a cement component in concrete depends upon the design strength, water demand and relative cost of ash compared to cement. The specific gravity and chemical properties of baryte cement, coarse and fine aggregate were determined. Cubes and the cylinder cubes werecured for 7 and 28 days respectively. The cubes and cylinder cubes were subjected to compressive strength tests after densitydetermination at 7 and 28 days respectively. The slump of different baryte percentage are compared
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Soultana, Athanasia, Michael Galetakis, Anthoula Vasiliou, Konstantinos Komnitsas i Despina Vamvuka. "Utilization of Upgraded Recycled Concrete Aggregates and Recycled Concrete Fines in Cement Mortars". Recent Progress in Materials 03, nr 03 (11.02.2021): 1. http://dx.doi.org/10.21926/rpm.2103035.
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Waste concrete is the most predominant constituent material among construction and demolition waste. Current waste concrete recycling is limited to the use of recycled concrete aggregates as a road-base material and less as aggregates in new concrete mixes. Further, the production of recycled concrete aggregates results in the generation of a high amount of fines, consisting mainly of cement paste particles. Hence, this study aims to produce the cement mortars using the upgraded recycled concrete aggregates (sand granulometry) for the total replacement of natural aggregates and recycled concrete fines activated through a thermal treatment method as a partial cement substitution material. Cement mortar specimens were tested for their compressive and flexural strength, density and water absorption performance. The results showed that the combined usage of upgraded recycled concrete sand for total replacement of primary crushed sand and recycled concrete fines as partial cement replacement material is a promising option to produce cement mortars.
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Kumar, Sudhir, i Manish Chaudhary. "Utilization of Waste Glass as Cement Replacement in PPC Concrete". International Journal of Trend in Scientific Research and Development Volume-2, Issue-3 (30.04.2018): 295–300. http://dx.doi.org/10.31142/ijtsrd10844.
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Babu, Repati Mohan, G. V. V. Satyanarayana i Vivek Kumar C. "Structural behaviour of triple blended high-performance concrete". E3S Web of Conferences 391 (2023): 01193. http://dx.doi.org/10.1051/e3sconf/202339101193.
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After water, concrete was the material for construction that is used on the largest scale on the planet, and as an outcome of technological development, concrete's qualities have evolved over time. A study was carried out to investigate the potential use of mineral admixture as a partial replacement in high performance concrete. Since they can significantly improve concrete strength and durability properties when compared to regular Portland cement supplemental cementations materials (SCM) like Alccofine (AF) and ground granulated blast furnace slag (GGBFS) have all been used as cement replacements on a large scale over the past three decades. As a result, HPC can be produced using lower water to powder ratios by including other cementitious materials as admixtures. In this project phase, ground granulated blast furnace slag (GGBFS) and Alccofine (AF) have been employed in varied weight ratios to substitute cement to produce high strength M40 grade concrete for 7, 14, and 28 days of compressive strength (CS) as well as split tensile strength (STS) the percentages of replacement of AF of 5%, 7.5% & 10% also GGBFS percentages are 10%, 12.5 % and 15% respectively used in this project work.
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Ge, Zhi, Ren Juan Sun i Li Zheng. "Mechanical Properties of Concrete with Recycled Clay-Brick-Powder". Advanced Materials Research 250-253 (maj 2011): 360–64. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.360.
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This paper studied the mechanical properties of concrete with cement partially replaced by recycled clay-brick-powder. Four variables (water/cement ratio, sand ratio, replacement level and average particle size of clay-brick-powder) were considered. Each variable had four levels. By using the orthogonal experimental design method, total 17 mixes, including one normal cement concrete as reference, were tested. Experiment results showed that recycled clay-brick-powder could be used as partial replacement of cement in concrete without reducing its properties. The strength was not significantly reduced with cement replacement level up to 25%. The elastic modulus was lower compared with cement concrete.
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Pavlů, Tereza, i Magdaléna Šefflová. "Carbonation Resistance of Fine Aggregate Concrete with Partial Replacement of Cement". Key Engineering Materials 722 (grudzień 2016): 201–6. http://dx.doi.org/10.4028/www.scientific.net/kem.722.201.
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The main aim of this contribution is verification of durability properties of concrete with partial replacement of cement by recycled cement powder (RCP) sourced from pure waste concrete. The main topic of this article is the study of influence of partial replacement of cement by RCP to the carbonation resistance of fine aggregate concrete with partial replacement of cement. The compressive strength, tensile strength in bending and depth of carbonation were tested after 56 days of CO2 curing. Partial replacement of cement was 0, 5, 10 and 15 % for all these tests. The properties were investigated by using prismatic specimens.
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Ketkukah, T. S., S. I. Anowai i F. G. Mije. "Performance of olive seed ash as partial replacement of cement in concrete". Nigerian Journal of Technology 41, nr 5 (9.11.2022): 827–33. http://dx.doi.org/10.4314/njt.v41i5.2.
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The need for partial replacement of cement in concrete production has become inevitable because of adverse environmental impact of cement production, increasing cost of cement and financial benefits of utilization of waste products. This paper presents laboratory investigation of the properties of Olive Seed Ash (OSA) as partial replacement of cement in concrete. Concrete mix of 1:2:4 (Binder: Fine aggregate: Coarse Aggregate) and water-cement ratio of 0.44 were adopted in this study. Olive seed ash was used to replace cement at various levels of 0%, 5%, 10% and 15% by mass. Partial replacement of cement with OSA resulted in decrease in initial and final setting times of concrete but the values are still within acceptable limits. The results show that compressive strength, flexural strength and split tensile strength of the concrete decreased as the percentage of OSA increases. However, at 10% replacement level, the 28 days compressive strength achieved was 28N/mm2 and this value surpasses the minimum compressive strength of 25N/mm2 recognized by BS EN 1992-1-1 (2004) for reinforced concrete design. The results also showed that the water absorption decreased with increase in percentage replacement of cement with OSA portraying that replacement with olive seed ash has higher durability potentials. It is recommended that cement can be replaced with at least 10% OSA in concrete. This will reduce the cost of construction in addition to environmental advantage.
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Ahiwale, Dhiraj, i Rushikesh Khartode. "Study of Fly Ash, Rice Husk Ash and Marble Powder as Partial Replacement to Cement in Concrete". International Journal of ChemTech Research 13, nr 3 (2020): 315–21. http://dx.doi.org/10.20902/ijctr.2019.130328.
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Now days, the waste rice husk from rice mill, marble powder from tile industry and fly ash from steam power plant are necessary to utilize as partial replacement of cement for concrete production. Large scale production of cement required consumption of raw materials and energy as well as emissions to air which posse’s environmental threat in various areas of country. Apart from the environmental threat, there still exists the problem of shortage in many areas. Therefore, substitute material for concrete needs to be considered. The paper aims to analyze the compressive strength of concrete cubes and flexural strength of concrete beams made from partially replaced cement, sand, and coarse aggregate. This research study adopted in laboratory on 48 total specimens of grade M25 concrete cubes of size 150x150x150mm and concrte beams of size 100x100x500mm were casted. Out of the 48 concrete specimens cast, 6 each were made out 10%, 20%, and 30 % replacement of fly ash, rice husk ash and marble powder to cement in concrete. It was found that the compressive strength and flexural strength of concrete made from the mixture of 20 % partially replaced cement, sand and coarse aggregate was similar than the concrete made from without replaced cement , sand and coarse aggregate.
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Jia, Fu Ping, Yong Cheng, Yi Bing Sun, Yin Yu Wang i Hao Sun. "Study on Residual Splitting Tensile Strength of HFCC after High Temperature". Advanced Materials Research 243-249 (maj 2011): 5067–70. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.5067.
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This paper presents the results of the splitting tensile strength of high fly ash content concrete (HFCC) after high temperature and analysis the degraded rules of the residual splitting strength subjected to high temperature and the replacements of cement by fly ash. The specimens were prepared with three different replacements of cement by fly ash 30%, 40% and 50% by mass and were tested after exposure to high temperature 250, 450, 550 and 650°C and room temperature respectively, compared with ordinary Portland cement concrete. The results showed that the splitting tensile strength sensitively decreased with the high temperature increased. Furthermore, the presence of fly ash was effective for improvement of the relative strength. The relative residual splitting strength of fly ash concrete was higher than those of ordinary Portland cement concrete except 30% fly ash replacement. Based on the experiments results, the alternating simulation formula to determine the relationship among relative residual strength, high temperature and fly ash replacement is developed by using regression of results, which provides the theoretical basis for the evaluation and repair of HFCC after high temperature.
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Kagadgar, Sarfaraz Ahmed, Suman Saha i C. Rajasekaran. "Mechanical and Durability Properties of Fly Ash Based Concrete Exposed to Marine Environment". Selected Scientific Papers - Journal of Civil Engineering 12, nr 1 (27.06.2017): 7–18. http://dx.doi.org/10.1515/sspjce-2017-0001.
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Abstract Efforts over the past few years for improving the performance of concrete suggest that cement replacement with mineral admixtures can enhance the strength and durability of concrete. Feasibility of producing good quality concrete by using alccofine and fly ash replacements is investigated and also the potential benefits from their incorporation were looked into. In this study, an attempt has been made to assess the performance of concrete in severe marine conditions exposed upto a period of 150 days. This work investigates the influence of alccofine and fly ash as partial replacement of cement in various percentages (Alccofine - 5% replacement to cement content) and (fly ash - 0%, 15%, 30%, 50% & 60% to total cementitious content) on mechanical and durability properties (Permit ion permeability test and corrosion current density) of concrete. Usage of alccofine and high quantity of fly ash as additional cementitious materials in concrete has resulted in higher workability of concrete. Inclusion of alccofine shows an early strength gaining property whereas fly ash results in gaining strength at later stage. Concrete mixes containing 5% alccofine with 15% fly ash replacement reported greater compressive strength than the other concrete mixes cured in both curing conditions. Durability test conducted at 56 and 150 days indicated that concrete containing higher percentages of fly ash resulted in lower permeability as well lesser corrosion density.