Journal articles: 'Portland cement with limestone'

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Tsivilis, Sotiris, and A. Asprogerakas. "A Study on the Chloride Diffusion into Portland Limestone Cement Concrete." Materials Science Forum 636-637 (January 2010): 1355–61. http://dx.doi.org/10.4028/www.scientific.net/msf.636-637.1355.

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In this paper the diffusion of chloride ions through limestone cement concrete is studied. The Portland limestone cements have many benefits and the new European Standard EN 197-1 identifies 4 types of Portland limestone cement containing 6-20% limestone (types II/A-L and II/A-LL) and 21-35% limestone (types II/B-L and II/B-LL), respectively. Portland limestone cements of different fineness and limestone content (0-35% w/w) have been produced by inter-grinding clinker, gypsum and limestone. Six concrete mixtures were prepared and the Nordtest Method (accelerated chloride penetration) was applied for the determination of penetration parameters for estimating the resistance against chloride penetration into hardened concrete. The diffusion equation of Fick’s second law was used for the determination of the effective chloride transport coefficient. It is concluded that Portland limestone cement concrete indicates competitive behavior with the Portland cement concrete. Limestone content up to 15% has a positive effect on the concrete resistance against chloride penetration.

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Kropyvnytska, Тetiana, Iryna Нeviuk, Roksolana Stekhna, Oksana Rykhlitska, and Lidiia Deschenko. "EFFECT OF LIMESTONE POWDER ON THE PROPERTIES OF BLENDED РORTLAND CEMENTS." Theory and Building Practice 2021, no. 1 (June 22, 2021): 35–41. http://dx.doi.org/10.23939/jtbp2021.01.035.

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The article shows the relation between sustainability and cement manufacture that can be obtained by the replacement of clinker with limestone additive. This decreases the use of energy resources and reduces CO2 emissions in cement production. The issue of partial Portland cement clinker substitution by finely ground limestone in the production of market-oriented types of cement type CEM II is solved on the cement plant PJSC "Ivano-Frankivsk Cement". The indexes of physical-mechanical tests of certified Portland limestone cement with high early strength CEM II/A-LL 42.5 R produced by PJSC "Ivano-Frankivsk Cement" are given. Finely dispersed limestone in Portland-composite cements with slag promotes a more complete synergic effect. It is established, that rapid-hardening blended Portland cements with limestone powder provide technological, technical, ecological, and economic effects in the production of prefabricated and monolithic reinforced concrete.

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Mrema, Alex Lyatonga. "Comparison of the Properties of Portland Cement and Portland-Limestone Cement." Tanzania Journal of Engineering and Technology 33, no. 1 (June 30, 2010): 1–8. http://dx.doi.org/10.52339/tjet.v33i1.448.

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A study was made in a cement factory in Dar es Salaam, Tanzania, where OrdinaryPortland Cement (CEM I 42.5N) and Portland-limestone cement (PLC) which has thebrand name Twiga Cement Extra (CEM II/A-L/32.5R) are produced and conforming to theTanzania Standard TZS 727 (Part1): 2002, which is equivalent to EN 197 published by thecommittee for European normalization (CEN). A comparison was made between the twotypes of cements in terms of physical, chemical and mechanical properties. It was foundout that they all complied with the standards, that there was no significant difference intheir setting times and that the Portland cement had higher strengths than the PLC. It was also observed that there was a slightly lower water demand for the same consistency when compared to OPC and hence there is an improvement of the cohesiveness of a concrete mix when PLC is used. It was concluded, however, that the two cements are different and that using the two cements interchangeably as is done in Tanzania is wrong because they donot have equivalent strengths and therefore equivalent performance since the PLC is not ptimized. Portland-limestone cement (PLC) is known to offer significant energy savings and green house gas (GHG) reduction (up to 10% GHG savings) over conventional Portland cement while at the same time providing comparable performance if optimized.

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Thomas, Michael, Laurent Barcelo, Bruce Blair, Kevin Cail, Anik Delagrave, and Ken Kazanis. "Lowering the Carbon Footprint of Concrete by Reducing Clinker Content of Cement." Transportation Research Record: Journal of the Transportation Research Board 2290, no. 1 (January 2012): 99–104. http://dx.doi.org/10.3141/2290-13.

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Significant efforts have been made to reduce carbon dioxide (CO2) emissions associated with the manufacture of portland cement, primarily by making the process more energy efficient and increasing the use of alternative fuels. Further reductions in CO2 can be achieved by lowering the clinker component of the cement because the pyroprocessing used to manufacture clinker produces approximately 1 tonne of CO2 for every tonne of clinker. Traditionally reductions in the clinker content of cement have been achieved by producing blended cement consisting of portland cement combined with a supplementary cementing material (SCM). In Canada, it is now permitted to intergrind up to 15% limestone with cement clinker to produce portland limestone cement or blended portland limestone cement. Recent trials were conducted at the Brookfield cement plant in Nova Scotia to evaluate the performance of a blended cement containing 15% ground, granulated blast furnace slag (an SCM) with that of a blended portland limestone cement containing the same amount of slag plus 12% interground limestone. Performance was evaluated by the construction of a section of concrete pavement using concrete mixtures produced with the two cements and various amounts of fly ash (another SCM). A wide range of laboratory tests were performed on the concrete specimens cast on site during the placement of the concrete pavement. The results indicated that the cements were of equivalent performance.

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Sotiriadis, K., E. Nikolopoulou, and Sotiris Tsivilis. "The Effect of Chlorides on the Thaumasite Form of Sulfate Attack in Limestone Cement Concrete." Materials Science Forum 636-637 (January 2010): 1349–54. http://dx.doi.org/10.4028/www.scientific.net/msf.636-637.1349.

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In this paper the effect of chlorides on the thaumasite form of sulfate attack in limestone cement concrete is studied. Concrete specimens made from ordinary Portland cement and two Portland limestone cements (limestone content 15% and 35% respectively) were prepared. After 28 days of curing the specimens were immersed in six solutions of various sulfate and chloride content and stored at 5oC. Visual assessment of the specimens, mass measurements and compressive strength tests took place for a period of 24 months. XRD method was used to identify thaumasite in the deteriorated parts of the specimens. All measurements showed that Portland cement concrete exhibits a lower degree of deterioration than Portland limestone cement concrete. Specimen disintegration was more severe, the higher the limestone contents of the cements and the higher the sulfate content of the corrosive storage solutions. Chlorides play an inhibitory role, delaying the deterioration of the concrete specimens. XRD analysis showed the presence of thaumasite at the deteriorated parts of the specimens after nine months of curing.

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Bassioni, Ghada. "GLOBAL WARMING AND CONSTRUCTION ASPECTS." Environment. Technology. Resources. Proceedings of the International Scientific and Practical Conference 2 (August 3, 2015): 78. http://dx.doi.org/10.17770/etr2009vol2.1013.

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The manufacture of cements with several main constituents is of particular importance with regard to reducing climatically relevant CO2 emissions in the cement industry. This ecological aspect is not the only argument in favor of Portland composite cements. They are also viable alternatives to Portland cement from the technical point of view. Substitution of ordinary Portland cement (CEM I) by Portland composite cements (CEM II) and (CEM III), which clearly possess different chemical and mineralogical compositions, results in changes of their reaction behavior with additives like superplasticizers. A common admixture to CEM I in that sense is limestone (industrial CaCO3). Its interaction with polycarboxylates is ignored and its inertness is taken for granted. This study provides a systematic approach in order to better understand the interaction of these polymeric superplasticizers with CaCO3 by adsorption and zeta potential measurements. The results give some fundamental understanding in how far the cement industry can reduce the production of cement clinker by replacing it with limestone as admixture and consequently the CO2-emission is reduced, which is of high political and environmental interest.

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Sanytsky, Myroslav, Tetiana Kropyvnytska, Taras Kruts, Oleksander Horpynko, and Iryna Geviuk. "Design of Rapid Hardening Quaternary Zeolite-Containing Portland-Composite Cements." Key Engineering Materials 761 (January 2018): 193–96. http://dx.doi.org/10.4028/www.scientific.net/kem.761.193.

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The strength development of a quaternary Portland cement composite system containing blast-furnace slag, zeolitic tuff and limestone powder is presented. The composition and particle size distribution of the constituents are optimized by the incremental coefficient of the surface activity of the zeolite-containing Portland composite cements. Zeolitic tuff and limestone powder of high specific surface area lead to the increase of the surface activity of the entire system and a corresponding improvement in the performance of the cement.

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Bassioni, Ghada. "LIMESTONE - AN INERT MODEL SYSTEM OF CEMENT?" Environment. Technology. Resources. Proceedings of the International Scientific and Practical Conference 1 (June 23, 2007): 108. http://dx.doi.org/10.17770/etr2007vol1.1713.

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The adsorption of small organic anions like those of benzoate, tartrate, citrate and glutamate on Portland composite cements СЕМ II and CEM III can be influenced by the present limestone (industrial СаСОз). Therefore, the replacement of ordinary Portland cement СЕМ I is not a trivial matter, although using these materials reduces the cement production and hence the C02 emission providing the solution of an up-to date environmental problem. A systematic study is shown here by zeta potential determination on the CaC03 suspension containing the organic anions. The effect of increasing pH leas' further considered and correlated to the adsorption on CaC03 surface. The study gives an insight on the compatibility between cement and organic additives in presence of limestone that has very similar surface properties to cement.

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Ghorab, Hanaa Y., Hossam E. H. Ahmed, Ali S. Shanour, and Hamdy M. A. Wahdan. "The Behavior of Portland Limestone-Calcined Clays Cement at 5°C." Key Engineering Materials 761 (January 2018): 135–43. http://dx.doi.org/10.4028/www.scientific.net/kem.761.135.

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The effect of calcined clays of the swelling type, on the strength and expansion behavior of Portland limestone cement is studied at 5°C. Local clays were thermally activated by burning one hour at 900 °C and were ground to a Blaine of 2842 (cm2/g). The pozzolanic reactivity of the activated clays was defined chemically and according to ASTM C311/C311M-13. Portland limestone cement was prepared by replacing 30% CEM I 42.5 N by limestone powder. Pozzolanic cements were prepared by replacing 10 and 20% of the limestone powder by calcined clays, the mixes were used to replace 30% of CEM I. Mortars specimens pre-cured for 28-day long as well as for a short period of one day, were immersed in sulfate solutions at 5°C for time up to 90 days. The compressive strength and length change were measured for the samples.The results show that replacement of limestone with calcined clays improves the compressive strength and the expansion of Portland limestone cement mortars in water and sulfate solutions. Ettringite was detected in the expanded mortars and no thaumasite formed. The results are interpreted in terms of the mechanism of thaumasite formation.

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FS, Hashem, Eisa E. Hekal, and Abdel M Wahab. "Effect propylene glycol as a quality improvers for Portland and Portland-limestone cements." International Journal of Petrochemical Science & Engineering 4, no. 1 (January 25, 2019): 1–7. http://dx.doi.org/10.15406/ipcse.2019.04.00096.

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The performance of propylene glycol (PG) on the grindability, setting and hardening of Portland (OPC) and Portland-Limestone cements (PLC) was studied. Propylene glycol was added to OPC clinker with percentage ratios; 0, 0.03, 0.04 and 0.05 wt.% of the OPC clinker. PLC was made by replacing 5 and 10 wt. % of OPC with limestone. PG offers better grinding aid performance with higher Blaine areas. Besides, presence of PG shows higher water of consistency and lower initial and final setting times. The mechanical properties of mortar specimens made from OPC and PLC admixed with PG were improved especially in the first 7 days. This explained due to increase in the cement fineness which leads to an increase in the degree of cement hydration, as well as to improvement in the interfacial transition zone between the cement paste and sand particles, thus resulting in an enhancement in the strength. DTA and SEM results confirmed the improved properties achieved due to admixing OPC or PLC with PG.

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FS, Hashem, Eisa E. Hekal, and Abdel M Wahab. "Effect propylene glycol as a quality improvers for Portland and Portland-limestone cements." International Journal of Petrochemical Science & Engineering 4, no. 1 (January 25, 2019): 1–7. http://dx.doi.org/10.15406/ipcse.2019.04.00096.

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The performance of propylene glycol (PG) on the grindability, setting and hardening of Portland (OPC) and Portland-Limestone cements (PLC) was studied. Propylene glycol was added to OPC clinker with percentage ratios; 0, 0.03, 0.04 and 0.05 wt.% of the OPC clinker. PLC was made by replacing 5 and 10 wt. % of OPC with limestone. PG offers better grinding aid performance with higher Blaine areas. Besides, presence of PG shows higher water of consistency and lower initial and final setting times. The mechanical properties of mortar specimens made from OPC and PLC admixed with PG were improved especially in the first 7 days. This explained due to increase in the cement fineness which leads to an increase in the degree of cement hydration, as well as to improvement in the interfacial transition zone between the cement paste and sand particles, thus resulting in an enhancement in the strength. DTA and SEM results confirmed the improved properties achieved due to admixing OPC or PLC with PG.

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12

Shao, Yixin, Vahid Rostami, Zhen He, and Andrew J. Boyd. "Accelerated Carbonation of Portland Limestone Cement." Journal of Materials in Civil Engineering 26, no. 1 (January 2014): 117–24. http://dx.doi.org/10.1061/(asce)mt.1943-5533.0000773.

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McDonald, Lewis, Fredrik Glasser, and Mohammed Imbabi. "A New, Carbon-Negative Precipitated Calcium Carbonate Admixture (PCC-A) for Low Carbon Portland Cements." Materials 12, no. 4 (February 13, 2019): 554. http://dx.doi.org/10.3390/ma12040554.

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The production of Portland cement accounts for approximately 7% of global anthropogenic CO2 emissions. Carbon CAPture and CONversion (CAPCON) technology under development by the authors allows for new methods to be developed to offset these emissions. Carbon-negative Precipitated Calcium Carbonate (PCC), produced from CO2 emissions, can be used as a means of offsetting the carbon footprint of cement production while potentially providing benefits to cement hydration, workability, durability and strength. In this paper, we present preliminary test results obtained for the mechanical and chemical properties of a new class of PCC blended Portland cements. These initial findings have shown that these cements behave differently from commonly used Portland cement and Portland limestone cement, which have been well documented to improve workability and the rate of hydration. The strength of blended Portland cements incorporating carbon-negative PCC Admixture (PCC-A) has been found to exceed that of the reference baseline—Ordinary Portland Cement (OPC). The reduction of the cement clinker factor, when using carbon-negative PCC-A, and the observed increase in compressive strength and the associated reduction in member size can reduce the carbon footprint of blended Portland cements by more than 25%.

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Wang, Yu Li, Wei Dong Wang, Yu Jie Zhao, and Su Xia Liu. "Influence of Limestone Powder on Immobilization of Chlorine Ion of Portland Cement." Advanced Materials Research 295-297 (July 2011): 1263–66. http://dx.doi.org/10.4028/www.scientific.net/amr.295-297.1263.

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The effect of limestone powder on immobilization of chlorine ion of Portland cement was studied by the method of the chemical analysis. The immobilization of chlorine ion of Portland cement, which was hardened by cement clinker or cement clinker and gypsum mixed limestone powder with different proportions, was tested at 28d. The results show that the amount of immobilization of chlorine ion of Portland cement increases more than doubled, and the free chlorine ion content decreases 41% without gypsum, when the limestone powder content increases from 0% to 12%; the immobilization content of chlorine ion increases first, and then decreases, the free chlorine ion content decreases a little with gypsum, when the limestone powder content increases from 0% to 8% .

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P, Sumardi, I. B. Agra, I. M. Bendiyasa, and Wahyudi B. S. "Kinetic Consideration of Clinker Formation in Portland Cement Production Using Demolition Rubbles (Concrete,mortar and plaster) Part I : Burning Ability of Raw Mixes." ASEAN Journal of Chemical Engineering 5, no. 2 (December 1, 2005): 169. http://dx.doi.org/10.22146/ajche.50186.

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Wahyudi B.S.Wahyudi B.S.In general, the main raw materials in Portland cement production are limestone, clay, and corrective materials such as iron sand and silica sand. These raw material come from natural deposits, which are very hard to find in some countries. In this research, Portland cement was made by utilizing the demolition rubble of office and housing buildings. The rubble consists of concrete wastes (mixtures of hydrated Portland cement minerals and some aggregates) and some building bricks as well as mortar/plaster of Portland cement. To meet the cement modulus, which is generally used in Portland cement industries, corrective materials such as limestone (source of CaO) and disposed building bricks are used. The term burning ability is used for Portland cement to measure the CaO free content in the cement clinker produced from specified raw material mixes at a specific operating 'condition of clinkering. The cement modulus used is Ume Saturation Factor (LSF) and Silica Modulus (SM). The minimum Cao free content was found by using LSF: 0.86, SM: 2.14, and clinkering temperature 14000C for 30 minutes. The cement modulus was made from concrete waste, limestone, and disposed red brick with a weight ratio of 1: 3.489: 0.677. Keywords: Burning ability,demolition rubble of buildings, Portland cement, and raw mixes.

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Sotiriadis, Konstantinos, Sotirios Tsivilis, and Vít Petranek. "Chloride Diffusion in Limestone Cement Concrete Exposed to Combined Chloride and Sulfate Solutions at Low Temperature." Advanced Materials Research 897 (February 2014): 171–75. http://dx.doi.org/10.4028/www.scientific.net/amr.897.171.

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The chloride diffusion in limestone cement concrete exposed to combined chloride and sulfate solutions at low temperature was studied. For this purpose, a normal Portland cement and two Portland limestone cements (15% and 35% w/w limestone content) were used for concrete preparation. The specimens were immersed in two combined chloride-sulfate solutions of different sulfate content, and stored at 5°C. The total and free chloride contents, as well as the chloride diffusion coefficients were determined for each concrete composition. The results show that the total chloride content and free to total chloride ratio are increased with time. The sulfate content of the corrosive solutions has not a clear effect on total chloride content and chloride diffusion coefficient. It seems that the lower sulfate content results, in general, in higher free to total chloride ratio values. The use of limestone in cement results in higher chloride concentrations in concrete and free to total chloride ratio values. In general, these phenomena are intensified for higher limestone content.

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Zhang, Feng Chen, Yun Zhao, and Fu Wan Zhu. "Erosion Phases in Two Types of Cement Pastes Containing Limestone Exposed to Sulfate Attack." Applied Mechanics and Materials 584-586 (July 2014): 1182–87. http://dx.doi.org/10.4028/www.scientific.net/amm.584-586.1182.

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Limestone filler and aggregates are used widely in cement production and concrete mixing nowadays, which could be connected with thaumasite formation, and lead to a lack of durability further. This work deals with the sulfate minerals including of thaumasite, ettringite and gypsum in two types of cement pastes containing 35% w/w limestone powder immersed in MgSO4 solution at 5°C±2°C for 15 weeks by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD). Two types of cements were used: (i) ordinary Portland cement (P·O), (ii) typeII Portland cement (P·II). Test results show that thaumasite is present in two types of cement pastes, amount of thaumasite as well as amount of portlandite reacted with external SO42- in P·II cement paste are more than those in P·O cement paste. It indicates that P·II cement is more susceptible to thaumasite formation than P·O cement containing the same amount of limestone powder, and more gypsum formation could contribute to thaumasite formation possibly during the external MgSO4 attack at low temperature.

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Chen, Chun Tao, Jiang Jhy Chang, Wei Chung Yeih, and Shun Ting Chang. "Sustainable Performance of Limestone Cement." Advanced Materials Research 476-478 (February 2012): 1692–96. http://dx.doi.org/10.4028/www.scientific.net/amr.476-478.1692.

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This study explores the effects of the limestone addition on the mechanical properties and durability of the cement. Portions of the Portland cements were replaced by the limestone powders. Results showed that the compressive strengths of the mortar were reduced by the limestone addition. In general, the addition of limestone helps to reduce the shrinkage and improve the sulfate attack resistance. The lowest sulfate-expansion occurred at the specimens with a limestone addition of 10%. Moreover, with additions of 10% or less, the reductions in strength were likely recovered by the addition of fly ash.

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Thongsanitgarn, Pailyn, Watcharapong Wongkeo, Sakprayut Sinthupinyo, and Arnon Chaipanich. "Effect of Limestone Powders on Compressive Strength and Setting Time of Portland-Limestone Cement Pastes." Advanced Materials Research 343-344 (September 2011): 322–26. http://dx.doi.org/10.4028/www.scientific.net/amr.343-344.322.

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In this study limestone powders with different particle sizes of 5, 10 and 20 μm were used to replace a part of Portland cement in different replacement levels to produce Portland-limestone cement pastes. The percentages of limestone replacement are 0, 5, 7.5, 10, 12.5, 15 and 20% by weight. The effect of fineness and the amount of limestone powders on compressive strength and setting time are investigated. It has been established that limestone replacement causes reduce the compressive strength due to the dilution effect, but it can reduce energy consumption and CO2 emission in cement manufacturing. The fineness of limestone powder used has influence on the observed compressive strength values. From the standard consistency results, it seems that limestone has no effect on water requirement compared to Portland cement. Moreover, the increase in level of fine particles would require much water. Both initial and final setting times were decreased with an increase in the amount of limestone. Furthermore, at the same level replacement, the cement pastes using 5 μm of limestone show lower setting time than those using 10 and 20 μm, respectively.

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Król, Anna, Zbigniew Giergiczny, and Justyna Kuterasińska-Warwas. "Properties of Concrete Made with Low-Emission Cements CEM II/C-M and CEM VI." Materials 13, no. 10 (May 14, 2020): 2257. http://dx.doi.org/10.3390/ma13102257.

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The paper presents the composition and properties of low-emission ternary cements: Portland multicomponent cement CEM II/C-M and multicomponent cement CEM VI. In the ternary cements, Portland clinker was replaced at the levels of 40% and 55% with a mixture of the main components such as limestone (LL), granulated blast furnace slag (S) and siliceous fly ash (V). Portland multicomponent cements CEM II/C-M and CEM VI are low-emission binders with CO2 emissions ranging from 340 (CEM VI) kg to 453 (CEM II/C-M) kg per Mg of cement. The results obtained indicate the possibility of a wider use of ground limestone (LL) in cement composition. This is important in the case of limited market availability of fly ash and granulated blast furnace slag. The tests conducted on concrete have shown that the necessary condition for obtaining a high strength class and durability of concrete from CEM II/C-M and CEM VI ternary cements is low water–cement ratio. Durability characteristics of concrete (carbonation susceptibility, chloride ion permeation, frost resistance) made of CEM II/C-M and CEM VI cements were determined after 90 days of hardening. This period of curing reflects the performance properties of the concrete in a more effective way.

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Guemmadi, Z’hor, Musa Resheidat, Hacéne Houari, and Belkacem Toumi. "OPTIMAL CRITERIA OF ALGERIAN BLENDED CEMENT USING LIMESTONE FINES/ALŽYRIETIŠKAS MIŠRUSIS CEMENTAS SU MALTU KALKAKMENIU." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 14, no. 4 (December 31, 2008): 269–75. http://dx.doi.org/10.3846/1392-3730.2008.14.26.

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The effect of substitution of Portland cement by limestone up to 40% as well as its fineness on the physico‐mechanical properties of fresh and hardened cement pastes is studied. The binder was prepared by substitution of cement by limestone filler. Fillers were chosen of various particle sizes and with percentages from 5 to 40. Test results revealed that the replacement of Portland cement by the finest filler of limestone slightly decreases the consistency and the setting times (initial and final). The total porosity decreases and accordingly the compressive strength is improved with the content and fines of limestone. Although limestone has a little accelerating effect on the hydration process of Portland cement, but acts only as a filler reducing the porosity due to its compact structure, in which the compressive strength of the hardened cement paste is enhanced. The XRD and DTA analyses of samples cured up to 28 days showed that this amelioration is due to formation of new hydrated compounds. It is concluded that an addition of finely ground limestone filler only up to 15% gives a better strength. Santrauka Tirtos šviežios ir sukietėjusios cementinės tešlos, kurioje iki 40 % cemento pakeista įvairaus smulkumo maltu kalkakmeniu, savybės. Rišiklis buvo paruoštas dalį cemento pakeitus maltu kalkakmenio užpildu. Užpildo dalelės buvo įvairaus dydžio, o jų kiekis buvo keičiamas nuo 5 % iki 40 %. Tyrimai parodė, kad priedas leidžia sumažinti vandens kiekį, reikalingą tos pačios konsistencijos mišiniui gauti, taip pat cemento rišimosi pradžiai ir pabaigai paankstinti. Sumažėja cementinio akmens suminis poringumas ir atitinkamai padidėja stipris gniuždant cementinio akmens, kuriame yra kalkakmenio priedų. Nors kalkakmenio priedas nedaug pagreitina portlandcemenčio hidratacijos procesą, tačiau veikia kaip užpildas, sutankinantis struktūrą, dėl to labai padidėja sukietėjusio cementinio akmens stipris gniuždant. Bandinių, išlaikytų 28 dienas, rentgenostruktūrinė ir diferencinė terminė analizė parodė, kad pagerėjimas yra dėl susidariusių naujadarų. Apibendrinant galima teigti, kad 15 % malto kalkakmenio priedas turi didžiausią įtaką stiprumo rezultatams.

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Sotiriadis, Konstantinos, Sotirios Tsivilis, Jana Kosíková, and Vít Petranek. "Long Term Behaviour of Portland Limestone Cement Concrete Exposed to Combined Chloride and Sulfate Environment. The Effect of Limestone Content and Mineral Admixtures." Advanced Materials Research 688 (May 2013): 185–92. http://dx.doi.org/10.4028/www.scientific.net/amr.688.185.

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The long term behaviour of limestone cement concrete, stored in combined chloride and sulfate environment, was studied, taking into consideration the effect of both the limestone content of the cement used and the mineral admixtures addition. Concrete specimens of seven different compositions were prepared. Three of them were made from ordinary Portland cement and from two Portland limestone cements (limestone content: 15% and 35% w/w). The rest four compositions were prepared by substituting a certain amount of the limestone cement (15% w/w limestone content) with natural pozzolana, fly ash, blastfurnace slag or metakaolin. The specimens were immersed in four solutions of various sulfate and chloride contents and stored at 5oC. Visual assessment of the specimens and mass measurements took place up to 55 months. XRD analytical technique was used to identify thaumasite in the deteriorated parts of the specimens. Higher contents of limestone in cement and of sulfates in the storage solutions resulted in more intensive concrete damage. The use of mineral admixtures improved the behaviour of limestone cement concrete. After 24 months of exposure, chlorides delay the deterioration of limestone cement concretes caused by sulfates. After 55 months, the presence of chlorides led to a greater mass loss for them. The specimens containing mineral admixtures showed more intensive deterioration at 24 months when chlorides were present along with sulfates. Their mass seems to not be affected by chlorides. Fly ash was proved as the most efficient material to improve limestone cement concrete's performance, while concrete containing metakaolin suffered from significant damage after 55 months. XRD analysis showed that the damage observed was due to the formation of thaumasite.

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Purnawan, Irfan, and Andi Prabowo. "Pengaruh Penambahan Limestone terhadap Kuat Tekan Semen Portland Komposit." Jurnal Rekayasa Proses 11, no. 2 (January 23, 2018): 86. http://dx.doi.org/10.22146/jrekpros.31136.

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Semen merupakan bahan dasar utama konstruksi bangunan, sehingga menjadikan semen sebagai komoditi yang strategis. Semen PCC (Portland Composite Cement) merupakan jenis semen varian baru yang mempunyai karakteristik mirip dengan semen Portland, tetapi semen jenis ini mempunyai kualitas yang lebih baik, ramah lingkungan dan mempunyai harga yang lebih ekonomis. Penambahan limestone sebagai aditif berfungsi meningkatkan kuat tekan pada semen. Tujuan penelitian ini adalah mengetahui pengaruh penambahan limestone dengan berbagai variasi terhadap kuat tekan dan menentukan massa limestone yang dapat memberikan kuat tekan maksimum pada semen Portland komposit. Pembuatan semen Portland komposit dilakukan dengan penambahan limestone sebagai aditif. Variasi limestone yang ditambakan adalah 0, 5, 10, 15, 20 dan 25%. Pengaruh penambahan limestone dapat diketahui dari hasil uji kehalusan, uji residu, uji komposisi kimia semen dan uji kuat tekan semen. Hasil penelitian menunjukan bahwa semakin besar persentase pemakaian limestone di dalam blended cement maka nilai residu dan nilai kehalusan akan semakin besar namun nilai kuat tekan akan semakin rendah. Kuat tekan semen yang tertinggi yaitu nilai kuat tekan pada umur 2 hari. Komposisi terbaik aditif limestone di dalam blended cement adalah 77% klinker, 15% lime stone, 3% gypsum dan 5% blast furnace slag

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Grilo, Maria J., João Pereira, and Carla Costa. "Waste Marble Dust Blended Cement." Materials Science Forum 730-732 (November 2012): 671–76. http://dx.doi.org/10.4028/www.scientific.net/msf.730-732.671.

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Marble processing activities generates a significant amount of waste in dust form. This waste, which is nowadays one of the environmental problems worldwide, presents great potential of being used as mineral addition in blended cements production. This paper shows preliminary results of an ongoing project which ultimate goal is to investigate the viability of using waste marble dust (WMD), produced by marble Portuguese industry, as cement replacement material. In order to evaluate the effects of the WMD on mechanical behaviour, different mortar blended cement mixtures were tested. These mixtures were prepared with different partial substitution level of cement with WMD. Strength results of WMD blended cements were compared to control cements with same level of incorporation of natural limestone used to produce commercial Portland-limestone cements. The results obtained show that WMD blended cements perform better than limestone blended cements for same replacement level up to 20% w/w. Therefore, WMD reveals promising attributes for blended cements production.

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Tsivilis, S., J. Tsantilas, G. Kakali, E. Chaniotakis, and A. Sakellariou. "The permeability of Portland limestone cement concrete." Cement and Concrete Research 33, no. 9 (September 2003): 1465–71. http://dx.doi.org/10.1016/s0008-8846(03)00092-9.

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Hartshorn, S. A., J. H. Sharp, and R. N. Swamy. "Thaumasite formation in Portland-limestone cement pastes." Cement and Concrete Research 29, no. 8 (August 1999): 1331–40. http://dx.doi.org/10.1016/s0008-8846(99)00100-3.

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Hájková, Iveta, Karel Dvořák, Dominik Gazdič, and Marcela Fridrichová. "Technological Properties Testing of Blended Portland Cements with Fluidized Filter Ash." Materials Science Forum 865 (August 2016): 27–31. http://dx.doi.org/10.4028/www.scientific.net/msf.865.27.

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The work aims to study the behaviour of blended cement with fluidized filter ash (FFA) considering to formation of the increased proportion of ettringite and its eventual transformation into thaumasite. In part of an experiment there were prepared three cements, two of them served as a reference one-component and the reference blended cement with limestone, a third one was tested blended cement with a FFA. All three cements were put to determination of basic technological properties and next they were observed during hydration process.

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Domanskaya, I. K., and Ekaterina S. Gerasimova. "Portland Cement with Mineral Fillers and Polymer Additives." Solid State Phenomena 284 (October 2018): 1063–68. http://dx.doi.org/10.4028/www.scientific.net/ssp.284.1063.

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This paper is devoted to the study of the hardening process and the mechanical properties of composite cements. There were three mineral additions and two polymer ones, namely fly ash, limestone meal and marble powder, polymer dispersion and redispersible polymer powder used. The principal possibility of combining mineral fillers in the design of composite cements is shown. It has been established that the samples of cement stone based on binders modified with redispersible polymer powder have higher compressive and flexural strength, regardless of the type of filler.

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Al-Mulla, Ikram F. Ahmed, Ammar S. Al-Rihimy, and Mushriq F. Al-Shamaa. "Compressive Strength and Shrinkage Behavior of Concrete Produced from Portland Limestone Cement with Water Absorption Polymer Balls." Key Engineering Materials 857 (August 2020): 83–88. http://dx.doi.org/10.4028/www.scientific.net/kem.857.83.

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From the sustainability point of view a combination of using water absorption polymer balls in concrete mix produce from Portland limestone cement (IL) is worth to be perceived. Compressive strength and drying shrinkage behavior for the mixes of concrete prepared by Ordinary Portland Cement (O.P.C) and Portland limestone cement (IL) were investigated in this research. Water absorbent polymer balls (WAPB) are innovative module in producing building materials due to the internal curing which eliminates autogenous shrinkage, enhances the strength at early age, improve the durability, give higher compressive strength at early age, and reduce the effect of insufficient external curing. Polymer balls (WAPB) had been used in the mixes of this research to provide good progress in compressive strength with time. Water absorption polymer balls have the ability to absorb water and after usage in concrete it will spill it out and shrink leaving voids of their own diameter before shrinking that lead to provide internal curing. The required quantity of water for the mixes were reduced due to the addition of water from the absorption polymers. Mixes produced from Portland limestone cement in this research show drying shrinkage results and compressive strength results lower than mixes made from ordinary Portland cement.

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Hameed, Rizwan, Joonho Seo, Solmoi Park, Issam T. Amr, and H. K. Lee. "CO2 Uptake and Physicochemical Properties of Carbonation-Cured Ternary Blend Portland Cement–Metakaolin–Limestone Pastes." Materials 13, no. 20 (October 19, 2020): 4656. http://dx.doi.org/10.3390/ma13204656.

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The feasibility of carbonation curing of ternary blend Portland cement–metakaolin–limestone was investigated. Portland cement was substituted by the combination of metakaolin and limestone at levels of 15%, 30%, and 45% by the mass. The ternary blends were cured with four different combinations of ambient and carbonation curing. The mechanical property, CO2 uptake, and mineralogical variations of the ternary blend pastes were investigated by means of compressive strength test, thermogravimetric analysis, and X-ray diffractometry. In addition, volume of permeable voids and sorptivity of the ternary blends were also presented to provide a fundamental idea of the pore characteristics of the blends. The test results showed that the increasing amount of metakaolin and limestone enhanced the CO2 uptake, reaching 20.7% for the sample with a 45% cement replacement level at 27 d of carbonation. Meanwhile, the compressive strength of the samples was reduced up to 65% upon excessive incorporation of metakaolin and limestone. The samples with a replacement level of 15% exhibited a comparable strength and volume of permeable voids to those of the sample without substitution, proving that the ternary blend Portland cement–metakaolin–limestone can be a viable option toward the development of eco-friendly binders.

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Magrla, Radek, Karel Kulísek, Karel Dvořák, and Dominik Gazdič. "Substitution of Limestone in Raw Mixture for Burning Portland Cement by FBC Ash." Advanced Materials Research 1124 (September 2015): 31–36. http://dx.doi.org/10.4028/www.scientific.net/amr.1124.31.

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This paper describes effort to reduce amount of gypsum in raw mixture for burning of Portland cement. Substitution of this material was realized by FBC ash. From these modified raw mixtures the clinkers were burnt, which were milled into cement then. These cements were subjected to basic technological tests.

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Macijauskas, Mindaugas, and Albinas Gailius. "INFLUENCE OF CEMENT TYPE AND ADMIXTURES ON RHEOLOGICAL PROPERTIES OF CEMENT PASTE / CHEMINIŲ ĮMAIŠŲ POVEIKIS REOLOGINĖMS CEMENTO TEŠLOS SAVYBĖMS." Engineering Structures and Technologies 5, no. 4 (May 8, 2014): 175–81. http://dx.doi.org/10.3846/2029882x.2014.912431.

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The article aims to research the influence of the chemical admixtures on the rheological properties of Portland cement paste and determine their impact on the effectiveness of hydration induction period. Materials used in the study: Portland cement CEM I 42.5 (N and R early strength), limestone Portland cement CEM II/A-LL 42.5 N, plasticizer Centrament N3, the latest generation superplasticizer MC-PowerFlow 3140 and water. Investigations focused on effects of Plasticizer and superplasticizer on water and cement (W/C) ratio and Portland cement paste flow characteristics. Portland cement pastes with the same watercement ratio with and without chemical admixtures were tested. Investigations were carried out using a Suttard viscometer and rotation viscometer Rheotest NH 4.1 with coaxial cylinders. It was observed that viscosity of Portland cement paste can be controlled by chemical admixtures during the hydration induction period. Investigations of effectiveness of the chemical admixtures on the rheological properties of the Portland cement pastes, comparing it with a control composition of the Portland cement paste were provided in the article. Diagrams show changes of the viscosity of the Portland cement pastes depending on the type and amount of the used chemical admixtures. Obtained results were compared with the same consistence without admixtures. After making the regressive analysis of research results of Portland cement paste with and without chemical admixtures, empirical equations were produced. Santrauka Šio darbo tikslas – ištirti cheminių įmaišų poveikį reologinėms portlandcemenčio tešlų savybėms ir nustatyti jų poveikio veiksmingumą indukcinio hidratacijos periodo metu. Tyrimams naudotos šios medžiagos: AB „Akmenės cementas“ gamyklos portlandcementis CEM I 42,5 (N ir R ankstyvojo stiprumo), klinties portlandcementis CEM II/A-LL 42,5 N, plastiklis Centrament N3, naujausios kartos superplastiklis MC-PowerFlow 3140 ir vanduo. Ištirtas plastiklio ir superplastiklio poveikis vandens ir cemento (V/C) santykio pokyčiams ir portlandcemenčio tešlų sklidumui naudojant Sutardo viskozimetrą. Buvo tiriamos vienodo vandens ir cemento santykio portlandcemenčio tešlos su cheminėmis įmaišomis ir be jų. Tyrimai atlikti naudojant rotacinį viskozimetrą Rheotest NH 4.1 su bendraašiais cilindrais. Nustatytas cheminių įmaišų portlandcemenčio tešlose veiksmingumas. Pastebėta, kad portlandcemenčio tešlų dinaminė klampa gali būti reguliuojama cheminėmis įmaišomis viso indukcinio hidratacijos periodo metu. Atlikus portlandcemenčio tešlų su cheminėmis įmaišomis ir be jų tyrimų rezultatų regresinę analizę, gautos empirinės lygtys.

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Bodnárová, Lenka, Tomáš Jarolím, Jaroslav Válek, Jiří Brožovský, and Rudolf Hela. "Selected Properties of Cementitous Composites with Portland Cements and Blended Portland Cements in Extreme Conditions." Applied Mechanics and Materials 507 (January 2014): 443–48. http://dx.doi.org/10.4028/www.scientific.net/amm.507.443.

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The paper is focused on research of physico-mechanical properties of concretes with Portland-limestone cement, Blastfurnace cement and Portland-composite cement in comparisom with concrete with Portland Cement CEM I. Following physico-mechanical properties of concretes exposed to extreme conditions were tested: compressive strength, flexural strength, tensille splitting strength, velocity of propagation of ultrasonic pulse, dynamic elasticity modulus and density of hardened concrete. Following environments were used in tests: sulphates, magnesic ions, nitrates, gaseous CO2, high temperatures.

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Ahmad, Muhammad, Muhammad Sajjad, Irfan Khan, Amina Durrani, Ali Durrani, Saeed Gul, and Asmat Ullah. "Sustainable production of blended cement in Pakistan through addition of natural pozzolana." Chemical Industry and Chemical Engineering Quarterly 22, no. 1 (2016): 41–45. http://dx.doi.org/10.2298/ciceq141012017a.

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In this work pozzolana deposits of district Swabi, Pakistan were investigated for partial substitution of Portland cement along with limestone filler. The cement samples were mixed in different proportions and tested for compressive strength at 7 and 28 days. The strength activity index (SAI) for 10 % pozzolana, and 5% limestone blend at 7 and 28 days was 75.5% and 85.0% satisfying the minimum SAI limit of ASTM C618. Twenty two percents natural pozzolana and five percents limestone were interground with clinker and gypsum in a laboratory ball mill to compare the power consumption with ordinary Portland cement (OPC) (95% clinker and 5% gypsum). The ternary blended cement took less time to reach to the same fineness level as OPC due to soft pozzolana and high grade lime stone indicating that intergrinding may reduce overall power consumption. Blended cement production using natural pozzolana and limestone may reduce the energy consumption and green house gas emissions.

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Zhou, Jie, Guang Ye, and Klaas van Breugel. "Early-Age Heat Evolution and Pore Structure of Portland Cement Blended with Blast Furnace Slag, Fly Ash or Limestone Powder." Key Engineering Materials 405-406 (January 2009): 242–46. http://dx.doi.org/10.4028/www.scientific.net/kem.405-406.242.

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Recently, blast furnace slag, fly ash and limestone powder are increasingly used as blending materials in producing concrete. The use of these materials not only has economical and environmental advantages, but also improves the mechanical properties, durability and workability of concrete. In this paper, the results of experimental investigations on the evolution of hydration heat and the development of microstructure of Portland cement blended with blast furnace slag, fly ash or limestone powder are presented. These results show that three blending materials accelerate the hydration of Portland cement, but result in less heat release during the first 72 hours. The Portland cement with blast furnace slag has a denser pore structure than the others.

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Fridrichová, Marcela, Radek Magrla, Dominik Gazdič, and Jana Stachová. "FBC-Ash as a Substitute of Part Material Raw during Production of Portland Cement." Advanced Materials Research 1100 (April 2015): 11–14. http://dx.doi.org/10.4028/www.scientific.net/amr.1100.11.

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In the last years we have to think about the question of emission reduction. One of the biggest producer of these emission is industry, where the cement industry comes under it. The effort of cement-workers and other manufacturers of building materials is the reduction of harmful oxides in our air, including CO2, which is one of a group of unfavourable oxides.This paper deals with the study possibility of partial compensation limestone by FBC-ash. The expected effect is the reduction of CO2 emissions and saving limestone. Following the previous stage of the research a recipes were designed for Portland clinker burning limestone-based and FBC ash, it was carried out laboratory burning and on produced cements were made basic technological tests.

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Ta Ngoc, Dung, Canh Nguyen Hoang, and Mai Pham Thanh. "EVALUATION OF EFFECT OF BLEND OF LIMESTONE AND GYPSUM ON THE COMPRESSIVE STRENGTH OF PORTLAND BLENDED CEMENT." Vietnam Journal of Science and Technology 57, no. 3A (October 28, 2019): 128. http://dx.doi.org/10.15625/2525-2518/57/3a/13933.

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The substitution of 5% cement clinker by 5% gypsum or 5% limestone additive as well as the fineness of limestone was studied about its effects on the strength of cement. The study show that the gypsum additive of 5% increase the strength of cement at the time of 1, 3, 7, 28 days (R= 55.1 MPa of cement with 5% substituted additive comparable to R= 45.3 MPa of cement with 100% clinker at the time of 28 days). The limestone additive of 5% increase the strength of cement at the early time of 1, 3, 7 days (R= 46.0 MPa of cement with 5% limestone additive comparable to R= 31.6 MPa of cement with 100% clinker at the time of 7 days). As well as, the strength of cement increase when the fineness of limestone increase.

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Boubekeur, Toufik, Bensaid Boulekbache, Mohamed Salhi, Karim Ezziane, and EL Hadj Kadri. "Beneficial Effect of Incorporation of Slag on the Hydration Heat, Mechanical Properties and Durability of Cement Containing Limestone Powder." MATEC Web of Conferences 330 (2020): 01047. http://dx.doi.org/10.1051/matecconf/202033001047.

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This paper presents the experimental results of a wide research program, tending to determine the hydration mechanism, mechanical properties and the durability performance of ternary cement containing limestone powder and slag. The limestone powder increase the hydration at early ages inducing a high strength at, but it can reduce the later strength due to the dilution effect. On the other hands, Slag (S) contributes to increase the compressive strength at later ages. Hence, at medium blended cement (OPC-LP-S) with better performance could be produced. Results show at later age the Slag is very effective in producing ternary blended cements with similar on higher compressive strength than the ordinary Portland cement at 28 and 90 days. For durability, the incorporation of the slag into the cement containing limestone powder improves remarkably resistance to attack by acids and sulfates and it has been found that the durability of the cements never depends on the mechanical strength.

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Chen, Guang Li, Xing Hua Fu, and Wen Hong Tao. "Preparation of Low-Heat Portland Cement Clinker with Coal Gangue." Advanced Materials Research 306-307 (August 2011): 861–64. http://dx.doi.org/10.4028/www.scientific.net/amr.306-307.861.

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A kind of low-heat Portland cement clinker was prepared with coal gangue, limestone and gypsum through optimizing the mix proportion of raw materials, and its properties and hydration characteristics were studied. The results showed that the cement clinker meeting the demands of mid (low)-heat Portland cement standard could be prepared with 35% (by weight, the same below) coal gangue, 57-60% limestone and 6-8% gypsum. The raw materials were burned at 1380°C for 40 minutes. The main hydrates were calcium silicate hydrate (C-S-H) gel, ettringite (AFt), monosulfate (AFm) and Ca(OH)2.

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Tang, Jin, Su Hua Ma, Wei Feng Li, Hui Yang, and Xiao Dong Shen. "Research Progress on the Hydration of Portland Cement with Calcined Clay and Limestone." Materials Science Forum 1036 (June 29, 2021): 240–46. http://dx.doi.org/10.4028/www.scientific.net/msf.1036.240.

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The use of calcined clay and limestone as supplementary cementitious materials, can have a certain influence on the hydration of Portland cement. This paper reviewed the influence of limestone and calcined clay and the mixture of limestone and calcined clay on the hydration of cement. Both limestone and calcined clay accelerate the hydration reaction in the early hydration age and enhance the properties of cement. Limestone reacts with C3A to form carboaluminate, which indirectly stabilized the presence of ettringite, while calcined clay consumed portlandite to form C-(A)-S-H gel, additional hydration products promote the densification of pore structure and increase the mechanical properties. The synergistic effect of calcined clay and limestone stabilize the existence of ettringite and stimulate the further formation of carboaluminate, as well as the C-(A)-S-H gel, contributed to a dense microstructure.

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Parvan, Marius-George, Georgeta Voicu, Alina-Ioana Badanoiu, Adrian-Ionut Nicoara, and Eugeniu Vasile. "CO2 Sequestration in the Production of Portland Cement Mortars with Calcium Carbonate Additions." Nanomaterials 11, no. 4 (March 30, 2021): 875. http://dx.doi.org/10.3390/nano11040875.

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The paper presents the obtention and characterization of Portland cement mortars with limestone filler and nano-calcite additions. The nano-calcite was obtained by the injection of CO2 in a nano-Ca(OH)2 suspension. The resulted nano-CaCO3 presents different morphologies, i.e., polyhedral and needle like crystals, depending on the initial Ca(OH)2 concentration of the suspension. The formation of calcium carbonate in suspensions was confirmed by X-ray diffraction (XRD), complex thermal analysis (DTA-TG), scanning electron microscopy (SEM) and transmission electron microscopy (TEM and HRTEM). This demonstrates the viability of this method to successfully sequestrate CO2 in cement-based materials. The use of this type of nano-CaCO3 in mortar formulations based on PC does not adversely modify the initial and final setting time of cements; for all studied pastes, the setting time decreases with increase of calcium carbonate content (irrespective of the particle size). Specific hydrated phases formed by Portland cement hydration were observed in all mortars, with limestone filler additions or nano-CaCO3, irrespective of curing time. The hardened mortars with calcium carbonate additions (in adequate amounts) can reach the same mechanical strengths as reference (Portland cement mortar). The addition of nano-CaCO3 in the raw mix increases the mechanical strengths, especially at shorter hardening periods (3 days).

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Samchenko, Svetlana V., Olga V. Alexandrova, and Anton Yu Gurkin. "Properties of cement composites based on limestone depending on their granulometric composition." Vestnik MGSU, no. 7 (July 2020): 999–1006. http://dx.doi.org/10.22227/1997-0935.2020.7.999-1006.

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Introduction. The use of limestone in cement compositions as an additional cementing agent solves both environmental and economic problems, namely, reduction of construction costs. In this regard, the study of the properties of the granulometric composition and volumetric content of cement composites, containing limestone, becomes increasingly important. The mission of this research is to optimize the properties of composite materials containing Portland cement and limestone by changing the granulometric composition of flour limestone. Materials and methods. Limestone, having three different Blaine milling fineness values of 250, 300 and 450 m2/kg, was used; its content reached 10, 15, 25 and 35 %. Cement and sand mortars were applied for testing purposes. The influence of the granulometric composition of limestone on the workability and compressive strength of composite cement was determined. Results. The effect of limestone on the limit shear stress becomes more pronounced when the amount of limestone increases to 25 and 35 %. This is most noticeable for limestone with a high content of fine fractions of 5–20 µm. The use of finely milled limestone increases the initial strength of the composite material. By adding 10 and 15 % of such limestone we can increase the strength by 16–20 %, and supplementary 25–35 % of limestone increases strength by 5–8 %. Strength enhancement is due to the reactivity of limestone and formation of calcium hydrocarbon aluminate 3CaO∙Al2O3∙СаСО3∙12H2O, which promotes formation of the crystal framework of the cement matrix. Additional formation of crystalline hydrates in the initial coagulation structure deteriorates the mortar workability, but increases its strength. Conclusions. The use of coarse-grained limestone significantly improves mortar workability, while the use of fine-grained limestone increases its content without reducing its strength. The granulometric composition of ground limestone shall be as close as possible to the granulometric composition of cement for the properties of composite materials containing Portland cement and limestone to be optimized.

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Gerasimova, Ekaterina S., and Kamila Masharipova. "Regulation of the Properties of Construction Composites Depending on the Material Composition." Materials Science Forum 989 (May 2020): 306–11. http://dx.doi.org/10.4028/www.scientific.net/msf.989.306.

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This paper is devoted to research of directional regulation possibility of the properties of a composite based on the Portland cement by using limestone waste. It is shown that the introduction of limestone waste contributes to changing the nature of crystallization and structure formation of cement stone. With the introduction of limestone waste, in the amount of 15 % by weight of cement, it is possible to obtain the compositions of the class not less than B25-B35.

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Odewale, Stephen A., Atilade A. Oladunni, and Babatunde O. Oyewale. "Chemical Characterization of Nine Locally Made Cement Products for Quality Assurance in Nigeria Cement Industry." European Journal of Engineering Research and Science 5, no. 12 (December 30, 2020): 126–29. http://dx.doi.org/10.24018/ejers.2020.5.12.2008.

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Chemical characterization of Portland limestone cement products collected across the nine existing cement manufacturing plants in Nigeria was conducted using Energy Dispersive X-ray Fluorescence Spectrometer (EDXRF) with the aim of determining conformity with global and local standards and investigating likely variation in quality resulting from differences in the sources of major raw materials, especially limestone used in production. The cement samples are composed essentially of CaO, SiO2, Al2O3, Fe2O3, MgO, Na2O, K2O and SO3 while P2O5, MnO and TiO2 were present in trace amount. In addition to oxide compositions, the mineralogical components: Alite (C3S), Belite (C2S), Celite (C3A), and Ferrite (C4AF), and other cement quality control variables such as Lime Saturation Factor, Silica Modulus and Alumina Modulus of all the nine cement samples analyzed in this study are in agreement with the specifications for Portland limestone cement published by the Standard Organisation of Nigeria (SON), the American Society for Testing and Materials (ASTM), and the British Standards Institution (BSI). The nine cement products also have their compositions in close proportion indicating none of the products is superior in quality irrespective of manufacturer or production site, a common misconception in the Nigerian cement market.

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Nadelman, Elizabeth I., and Kimberly E. Kurtis. "Application of Powers’ model to modern portland and portland limestone cement pastes." Journal of the American Ceramic Society 100, no. 9 (May 8, 2017): 4219–31. http://dx.doi.org/10.1111/jace.14913.

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Kakali, G., R. Leventi, V. Benekis, and S. Tsivilis. "Behavior of blended cement pastes at elevated temperature." Chemical Industry and Chemical Engineering Quarterly 12, no. 2 (2006): 133–36. http://dx.doi.org/10.2298/ciceq0602133k.

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Fire can cause severe damage to building structures. This fact has increased the importance of the fire resistance of concrete. The consideration of the fire resistance of concrete requires the complete knowledge of the behaviour of each concrete component under elevated temperatures. The resistance of blended cement pastes upon heating was studied in the present paper. Natural pozzolana, fly ash, ground granulated blast-furnace slag, metakaolin and limestone were used as the main cement constituents. Blended cements were prepared by replacing a part of Portland Cement (PC) with the minerals mentioned above (10% w/w in the case of metakaolin, 20% w/w in the case of the rest materials). The specimens were water-cured for 3 months and then they were thermally treated at 200, 400, 600 800 and 1000?C for 1h. Visual inspection, mass measurements and ultrasonic pulse velocity measurements were carried out after each thermal treatment. It was concluded that the cohesion of the pastes was strongly affected by the kind of the main constituent, added to the Portland cement. The use of pozzolanic materials and especially metakaolin improved the fire resistance of the pastes, while the samples with limestone show the worst behavior.

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SOUZA, D. J. DE, M. H. F. MEDEIROS, and J. HOPPE FILHO. "Evaluation of external sulfate attack (Na2SO4 and MgSO4): Portland cement mortars containing fillers." Revista IBRACON de Estruturas e Materiais 13, no. 3 (June 2020): 644–55. http://dx.doi.org/10.1590/s1983-41952020000300013.

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Abstract Sulfate attack is a term used to describe a series of chemical reactions between sulfate ions and hydrated compounds of the hardened cement paste. The present study aims to evaluate the physical (linear expansion, flexural and compressive strength) and mineralogical properties (X-ray diffraction) of three different mortar compositions (Portland Cement CPV-ARI with limestone filler and, with a quartz filler, in both cases with 10% replacement of the cement by weight) against sodium and magnesium sulfate attack (concentration of SO4 2- equal to 0.7 molar). The data collected indicate that the replacing the cement by the two fillers generate different results, the quartz filler presented a mitigating behaviour towards the sulfate, and the limestone filler was harmful to Portland cement mortars, in both physical and chemical characteristics.

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Tiburzi, Nicolas B., Jose Garcia, Thano Drimalas, and Kevin J. Folliard. "Sulfate resistance of portland-limestone cement systems containing greater than 15% limestone." Cement and Concrete Composites 100 (July 2019): 60–73. http://dx.doi.org/10.1016/j.cemconcomp.2019.03.024.

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Bediako, Mark, and Eric Opoku Amankwah. "Analysis of Chemical Composition of Portland Cement in Ghana: A Key to Understand the Behavior of Cement." Advances in Materials Science and Engineering 2015 (2015): 1–5. http://dx.doi.org/10.1155/2015/349401.

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The performance of Portland cement in concrete or mortar formation is very well influenced by chemical compositions among other factors. Many engineers usually have little information on the chemical compositions of cement in making decisions for the choice of commercially available Portland cement in Ghana. This work analyzed five different brands of Portland cement in Ghana, namely, Ghacem ordinary Portland cement (OPC) and Portland limestone cement (PLC), CSIR-BRRI Pozzomix, Dangote OPC, and Diamond PLC. The chemical compositions were analyzed with X-Ray Fluorescence (XRF) spectrometer. Student’st-test was used to test the significance of the variation in chemical composition between standard literature values and each of the commercial cement brands. Analysis of variance (ANOVA) was also used to establish the extent of variations between chemical compositions and brand name of the all commercial Portland cement brands. Student’st-test results showed that there were no significant differences between standard chemical composition values and that of commercial Portland cement. The ANOVA results also indicated that each brand of commercial Portland cement varies in terms of chemical composition; however, the specific brands of cement had no significant differences. The study recommended that using any brand of cement in Ghana was good for any construction works be it concrete or mortar formation.

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Bazne, Mohammed O. A., Isaac L. Howard, and Farshid Vahedifard. "Stabilized Very High–Moisture Dredged Soil: Relative Behavior of Portland-Limestone Cement and Ordinary Portland Cement." Journal of Materials in Civil Engineering 29, no. 9 (September 2017): 04017110. http://dx.doi.org/10.1061/(asce)mt.1943-5533.0001970.

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Journal articles on the topic 'Portland cement with limestone'

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