Effects of Blended-Cement Paste Chemical Composition Changes on Some Strength Gains of Blended-Mortars

Effects of chemical compositions changes of blended-cement pastes (BCPCCC) on some strength gains of blended cement mortars (BCMSG) were monitored in order to gain a better understanding for developments of hydration and strength of blended cements. Blended cements (BC) were prepared by blending of 5% gypsum and 6%, 20%, 21%, and 35% marble powder (MP) or 6%, 20%, 21%, and 35% brick powder (BP) for CEMI42.5N cement clinker and grinding these portions in ball mill at 30 (min). Pastes and mortars, containing the MP-BC and the BP-BC and the reference cement (RC) and tap water and standard mortar sand, were also mixed and they were cured within water until testing. Experiments included chemical compositions of pastes and compressive strengths (CS) and flexural strengths (FS) of mortars were determined at 7th-day, 28th-day, and 90th-day according to TS EN 196-2 and TS EN 196-1 present standards. Experimental results indicated that ups and downs of silica oxide (SiO2), sodium oxide (Na2O), and alkali at MP-BCPCC and continuously rising movement of silica oxide (SiO2) at BP-BCPCC positively influenced CS and FS of blended cement mortars (BCM) in comparison with reference mortars (RM) at whole cure days as MP up to 6% or BP up to 35% was blended for cement.

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Chemical Properties of Substituted and Blended Cements

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.749.477 ◽

2013 ◽

Vol 749 ◽

pp. 477-482 ◽

Cited By ~ 1

Author(s):

Mehmet Serkan Kirgiz

Keyword(s):

Experimental Study ◽

Chemical Properties ◽

Blended Cement ◽

Cement Clinker ◽

Alkali Silica Reaction ◽

Environmental Aspect ◽

Blended Cements ◽

Brick Powder

The aim of the experimental study is to determine chemical properties of substituted and blended cement contained marble and brick powders to provide efficacy for the economical and the environmental aspect. Marble and brick powders, CEM I 42.5N cement and clinker were used as materials in the study. Substituted cements were prepared with the addition of cement for marble or brick powder at the ratios of % 6, 20, 21, 35. Blended cements were mixed the addition of cement clinker for marble or brick powder at the ratios of % 6, 20, 21, 35. And CEM I 42.5N cements were also chosen as Reference cement. Results show that marble and brick powders can prevalently add as substitute or blend materials to cement to prevent it detrimental chemicals like alkali-silica reaction.

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Physical Characterization and Durability of Blended Cements Based on Brick Powder

Civil and Environmental Engineering Reports ◽

10.2478/ceer-2020-0040 ◽

2020 ◽

Vol 30 (3) ◽

pp. 201-213

Author(s):

Ghania Nigri ◽

Yacine Cherait ◽

Soraya Nigri

Keyword(s):

Mechanical Properties ◽

Sulfuric Acid ◽

Research Work ◽

Blended Cement ◽

Waste Materials ◽

Partial Substitution ◽

Blended Cements ◽

Brick Powder ◽

Crushed Brick ◽

Durability Performance

Abstract This research work discusses both the physical and durability characteristics of newly blended cement containing waste crushed brick. This waste is used as a partial substitution for clinker in cement. Thus, blended cements are obtained by grinding and homogenizing clinker, waste brick, and gypsum. Four compositions containing 0%, 10%, 20%, and 30% of waste materials were prepared and submitted to various characterization tests. The introduction of brick powder improved the physical characteristics, therefore; it improved the mechanical properties and durability performance of the new cement compared to the reference, prepared with 0% addition. More particularly, it resisted sulfuric acid (H2SO4) attack after fixation of portlandite by pozzolan.

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The Effect of Micronized Waste Marble Powder as Partial Replacement for Cement on Resulting Mechanical Properties of Cement Pastes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1144.54 ◽

2017 ◽

Vol 1144 ◽

pp. 54-58

Author(s):

Zdeněk Prošek ◽

Karel Šeps ◽

Jaroslav Topič

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Reference Material ◽

Dynamic Modulus ◽

Blended Cement ◽

Partial Replacement ◽

Dynamic Shear Modulus ◽

Dynamic Shear ◽

Cement Pastes ◽

Marble Powder

This article was focused on the influence of the micronized waste marble powder on mechanical properties of cement pastes. Resulting blended cement was composed of Portland cement CEM I 42.5 R and micronized marble powder with different percentage amounts (0 wt. %, 5 wt. %, 10 wt. % and 15 wt. %). Testing was carried at prismatic samples of dimension 40 × 40 × 160 mm. The investigated mechanical properties were dynamic modulus of elasticity, dynamic shear modulus, flexural strength and compressive strength for the 28 days old samples. The results obtained from these materials were compared with reference material.

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Relationships Between Permeability, Porosity, Diffusion And Microstructure Of Cement Pastes, Mortar, And Concrete At Different Temperatures

MRS Proceedings ◽

10.1557/proc-137-179 ◽

1988 ◽

Vol 137 ◽

Cited By ~ 13

Author(s):

Della M. Roy

Keyword(s):

Pore Structure ◽

Elevated Temperatures ◽

Mercury Porosimetry ◽

Blended Cement ◽

Ionic Species ◽

Chloride Diffusion ◽

Concrete Durability ◽

Chloride Permeability ◽

Cement Pastes ◽

Blended Cements

AbstractPermeabilities to water and diffusion of ionic species in cementitious grouts, pastes and mortars are important keys to concrete durability. Investigations have been made of numerous materials containing portland and blended cements, and those with fine-grained filler, at room temperature and after prolonged curing at several elevated temperatures up to 90°C. These constitute part of studies of fundamental material relationships performed in order to address the question of long-term durability. In general, the permeabilities of the materials have been found to be low [many <10−8 Darcy (10−13 m·s−1)] after curing for 28 days or longer at temperatures up to 60°C. The results obtained at 90°C are somewhat more complex. In some sets of studies of blended cement pastes with w/c varying from 0.30 to 0.60 and cured at temperatures up to 90°C the more open-pore structure (at the elevated temperature and higher w/c) as evident from SEM microstructural studies as well as mercury porosimetry are generally correlated also with a higher permeability to liquid. The degree of bonding and permeability evident in paste or mortar/rock interfacial studies present somewhat more conflicting results. The bond strength (tensile mode) has been shown to be improved in some materials with increased temperature. The results of permeability studies of paste/rock couples show examples with similar low permeabilities, and some with increased permeability with temperature.Ionic diffusion studies also bring important bearing to understanding the effect of pore structure. The best interrelationships between chloride diffusion and pore structure appear to relate diffusion rate to median pore size. Similar results were found with “chloride permeability” test.

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Behaviour and Properties of Eco-Cement Pastes Elaborated with Recycled Concrete Powder from Construction and Demolition Wastes

Materials ◽

10.3390/ma14051299 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1299

Author(s):

Laura Caneda-Martínez ◽

Manuel Monasterio ◽

Jaime Moreno-Juez ◽

Sagrario Martínez-Ramírez ◽

Rosario García ◽

...

Keyword(s):

Blended Cement ◽

Recycled Concrete ◽

Environmental Benefits ◽

Construction And Demolition Waste ◽

Replacement Rate ◽

Demolition Waste ◽

Cement Pastes ◽

Blended Cements ◽

Construction And Demolition Wastes ◽

Refinement Process

This work analyses the influence of fine concrete fractions (<5 mm) of different natures —calcareous (HcG) and siliceous (HsT)—obtained from construction and demolition waste (C&DW) on the behaviour of blended cement pastes with partial replacements between 5 and 10%. The two C&DW fractions were characterised by different instrumental techniques. Subsequently, their lime-fixing capacity and the physico-mechanical properties of the blended cement pastes were analysed. Lastly, the environmental benefits of reusing these fine wastes in the manufacture of future eco-efficient cement pastes were examined. The results show that HsT and HcG exhibit weak pozzolanic activity, owing to their low reactive silica and alumina content. Despite this, the new cement pastes meet the physical and mechanical requirements of the existing regulations for common cements. It should be highlighted that the blended cement pastes initially showed a coarser pore network, but then they underwent a refinement process between 2 and 28 days, along with a gain in compressive strength, possibly due to the double pozzolanic and filler effect of the wastes. The environmental viability of the blended cements was evaluated in a Life Cycle Assessment (LCA) concluding that the overall environmental impact could be reduced in the same proportion of the replacement rate. This is in line with the Circular Economy goals and the 2030 Agenda for Sustainable Development.

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Chemical Composition and Physical Characteristics of Rice Husk Ash Blended Cement

International Journal of Engineering Research in Africa ◽

10.4028/www.scientific.net/jera.32.25 ◽

2017 ◽

Vol 32 ◽

pp. 25-35 ◽

Cited By ~ 7

Author(s):

Akeem Ayinde Raheem ◽

Mutiu A. Kareem

Keyword(s):

Compressive Strength ◽

Rice Husk ◽

Rice Husk Ash ◽

Blended Cement ◽

Physical Characteristics ◽

Chemical Compositions ◽

Minimum Requirement ◽

Suitable Material ◽

Blended Cements ◽

Renewable Material

Applications of agricultural by-product as substitute for non-renewable material in cement production are desirable in stimulating socio-economic development. In this study, Rice Husk Ash (RHA) blended cement was produced by replacing 5%, 7%, 11.25%, 15%, 20.25% and 25% by weight of Ordinary Portland Cement (OPC) clinker with RHA. The cement without RHA serves as the control. The chemical compositions of RHA, OPC-clinker and the blended cements were determined using X-ray fluorescence analyzer. The physical characteristics of RHA blended cements that were considered are fineness, soundness, consistency, initial and final setting times and compressive strength at 2, 7, 28, 56 and 90 curing ages. The results showed that RHA is a suitable material for use as a pozzolan as it satisfied the minimum requirement by having the sum of SiO2, Al2O3 and Fe2O3 of more than 70%. Incorporation of RHA led to an increase in the composition of SiO2 and reduction in that of CaO. An increase in RHA content showed a decrease in compressive strength at early ages and slightly increase at a later age (90 days). The blended cement produced with lower levels of RHA replacement conforms to standard specifications specified in BS EN 197-1:2000, NIS 439:2000 and ASTM C 150-02. The minimum Strength Activated Index (SAI) of 75% at the age of 28 days of curing as specified by ASTM C 618 was satisfied by RHA replacement of up to 15%. It was concluded that blended cement with the maximum of 15% RHA content is suitable for use for structural purposes.

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Behavior of blended cement pastes at elevated temperature

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq0602133k ◽

2006 ◽

Vol 12 (2) ◽

pp. 133-136

Author(s):

G. Kakali ◽

R. Leventi ◽

V. Benekis ◽

S. Tsivilis

Keyword(s):

Portland Cement ◽

Fire Resistance ◽

Elevated Temperatures ◽

Blended Cement ◽

Ultrasonic Pulse Velocity ◽

Ultrasonic Pulse ◽

Pulse Velocity ◽

Building Structures ◽

Cement Pastes ◽

Blended Cements

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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The effects of seawater and nanosilica on the performance of blended cements and composites

Applied Nanoscience ◽

10.1007/s13204-020-01328-8 ◽

2020 ◽

Vol 10 (12) ◽

pp. 5009-5026 ◽

Cited By ~ 6

Author(s):

Pawel Sikora ◽

Didier Lootens ◽

Maxime Liard ◽

Dietmar Stephan

Keyword(s):

Transport Properties ◽

Reaction Rate ◽

Mechanical Performance ◽

Setting Time ◽

Blended Cement ◽

Heat Of Hydration ◽

Strength Development ◽

Cement Pastes ◽

Blended Cements ◽

Setting Times

AbstractThis study investigates the effects of seawater and nanosilica (3% by weight of cement), on the fresh and hardened properties of cement pastes and mortars produced with two types of low heat cements: Portland pozzolana cement (CEM II) and blast furnace cement (CEM III). The heat of hydration, initial and final setting times, rheological properties, strength development, sorptivity and water accessible porosity of the cement pastes and mortars were determined. The data reveal that cement type has a significant effect on the reaction rate of cement with seawater and nanosilica (NS). Specimens produced with slag-blended cement exhibited a higher cement reaction rate and the composite produced exhibited better mechanical performance, as a result of the additional reaction of alumina rich phases in slag, with seawater. Replacement of freshwater with seawater contributes mostly to a significant improvement of early strength. However, in the case of slag-blended cement, 28 day strength also improved. The incorporation of NS results in additional acceleration of hydration processes, as well as to a decrease in cement setting time. In contrast, the addition of NS results in a noticeable increment in the yield-stress of pastes, with this effect being pronounced when NS is mixed along with seawater. Moreover, the use of seawater and NS has a beneficial effect on microstructure refinement, thus improving the transport properties of cement mortars. Overall, the study has showed that both seawater and NS can be successfully used to accelerate the hydration process of low heat blended cements and to improve the mechanical and transport properties of cement-based composites.

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Characteristic Properties of Marble and Brick Powders

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.749.483 ◽

2013 ◽

Vol 749 ◽

pp. 483-490 ◽

Cited By ~ 2

Author(s):

Mehmet Serkan Kirgiz

Keyword(s):

Cement Clinker ◽

Brick Powder ◽

Marble Powder ◽

Pozzolanic Properties ◽

Marble Waste

The paper was incisive about marble and brick wastes problem. In Turkey, annual approximately 2 592 000 t marble waste and 3 800 000 t brick waste are turn out while marble and brick manufactures. These wastes are stored agrarian land so they are contaminated environment and terrain. Chemical, physical, and pozzolanic properties of the marble and brick powders described characteristic properties were helped whether to use them as mineralogical substitute or blend in cement or not. The aim of this study is to establish characteristic properties of marble and brick powders. Tekmar Marble Factory's marble powder and Kaman Brick Factory's brick powder were used as materials. Characteristic properties of the marble and brick powders were lie down via standard experiment methods known literature. Results show that the powders are compatible to add cement clinker or to substitute for cement to improve their properties.

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The Effect of SCMs in Blended Cements on Sorption Characteristics of Superabsorbent Polymers

Materials ◽

10.3390/ma14071609 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1609

Author(s):

Rohollah Rostami ◽

Agnieszka J. Klemm ◽

Fernando C. R. Almeida

Keyword(s):

Portland Cement ◽

Chemical Properties ◽

Blended Cement ◽

Cementitious Materials ◽

Absorption Capacity ◽

Supplementary Cementitious Materials ◽

Partial Replacement ◽

Chemical Compositions ◽

Superabsorbent Polymers ◽

Blended Cements

Supplementary cementitious materials (SCMs), such as fly ash (FA) and ground granulated blast-furnace slag (GGBS), are often used as a partial replacement of cements to improve the sustainability of Portland cement-based materials and reduce their environmental impact. Superabsorbent polymers (SAPs) can be successfully used as internal curing agents in ultra-high performance cementitious materials by facilitating the hydration process and controlling the water supply in both fresh and hardened states. This paper intends to characterise the physical and chemical properties of SAPs and their sorption properties in different blended cement environments. The swelling capacity and kinetics of absorption of three superabsorbent polymers with different chemical compositions and grading were tested in different cement environments. Experimental results of their sorption performance in distinct solutions, including deionised water (DI), Portland cement (PC), and blended cements (PC-FA and PC-GGBS) and changes in pH of different solutions over time were investigated. The results showed that PC-FA solution had the lowest pH followed by PC-GGBS solution. Moreover, SAPs samples displayed the highest absorption capacities in PC-FA solutions, and the lowest swelling capacities were found in PC-GGBS solutions. Furthermore, SAP with smaller particle sizes had the greatest absorption capacity values in all solutions.

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