Use of Algerian Natural Mineral Deposit as Supplementary Cementitious Materials

2018 ◽  
Vol 34 ◽  
pp. 48-58 ◽  
Author(s):  
Karima Arroudj ◽  
Saida Dorbani ◽  
Mohamed Nadjib Oudjit ◽  
Arezki Tagnit-Hamou
Keyword(s):  
Mechanical Strength ◽  
Calcium Hydroxide ◽  
Cement Paste ◽  
Cementitious Materials ◽  
Pozzolanic Reaction ◽  
Heat Of Hydration ◽  
Cement Industry ◽  
Supplementary Cementitious Materials ◽  
Natural Mineral ◽  
Different Ages

Much of the current research on concrete engineering has been focused on including siliceous additions as supplementary cementitious materials (SCMs). Silica reacts with Calcium hydroxide release during cement hydration, and produces more C-S-H. The latter contributes to increase compactness, mechanical strengths and sustainability of concrete. This paper explores the hydration characteristics of cement paste based on various natural mineral additions, that are very abundant in Algeria and present a high silica content (ground natural pozzolana “PZ” and ground dune sand “DS”). For this purpose, several analyses were carried out on modified cement pastes and mortars. TheseSCMswere introduced by replacement levels of 15, 20 and 25 by weight of cement. We first, studied the effect of these SCMs on the heat of hydration and mechanical strength of mortars at different ages. The evolution of hydration of modified paste was studied, by using Thermal analysis (TG/TDA) at different ages, to analyze the Calcium Hydroxide (CH) content of the modified pastes. It is shown that the CH content of the mixes including SCMs is lower than that of the plain cement paste, indicating that silica reacts with the cement paste through a pozzolanic reaction. Increased pozzolanic activity results in higher amounts of Calcium Silicate Hydrate in the paste, which in turn results in higher compressive strength for modified cement mortars. Due to its crystalline morphology, the ground DS particles present a partial pozzolanic effect, compared to PZ which is semi-crystalline. Modified mortars by 20% DS can be the optimal composition. It presents satisfactory results: good mechanical strength and low heat of hydration. It can lead to an economic and sustainable concrete. Ground DS is very abounded in Africa and free of any impurities and can be a good alternativeSCMsin cement industry.

scholarly journals Hydration–Strength–Workability–Durability of Binary, Ternary, and Quaternary Composite Pastes

Materials ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 204
Author(s):  
Yi Han ◽  
Seokhoon Oh ◽  
Xiao-Yong Wang ◽  
Run-Sheng Lin
Keyword(s):  
Compressive Strength ◽  
Cement Paste ◽  
Carbon Emissions ◽  
Cementitious Materials ◽  
Heat Of Hydration ◽  
Surface Resistivity ◽  
Cement Industry ◽  
Supplementary Cementitious Materials ◽  
Limestone Powder ◽  
Alternative Materials

At present, reducing carbon emissions is an urgent problem that needs to be solved in the cement industry. This study used three mineral admixtures materials: limestone powder (0–10%), metakaolin (0–15%), and fly ash (0–30%). Binary, ternary, and quaternary pastes were prepared, and the specimens’ workability, compressive strength, ultrasonic pulse speed, surface resistivity, and the heat of hydration were studied; X-ray diffraction and attenuated total reflection Fourier transform infrared tests were conducted. In addition, the influence of supplementary cementitious materials on the compressive strength and durability of the blended paste and the sustainable development of the quaternary-blended paste was analyzed. The experimental results are summarized as follows: (1) metakaolin can reduce the workability of cement paste; (2) the addition of alternative materials can promote cement hydration and help improve long-term compressive strength; (3) surface resistivity tests show that adding alternative materials can increase the value of surface resistivity; (4) the quaternary-blended paste can greatly reduce the accumulated heat of hydration; (5) increasing the amount of supplementary cementitious materials can effectively reduce carbon emissions compared with pure cement paste. In summary, the quaternary-blended paste has great advantages in terms of durability and sustainability and has good development prospects.

scholarly journals A Mass Balance Approach for Thermogravimetric Analysis in Pozzolanic Reactivity R3 Test and Effect of Drying Methods

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5859
Author(s):  
Kira Weise ◽  
Neven Ukrainczyk ◽  
Eduardus Koenders
Keyword(s):  
Thermogravimetric Analysis ◽  
Mass Balance ◽  
Calcium Hydroxide ◽  
Cementitious Materials ◽  
Pozzolanic Reaction ◽  
Supplementary Cementitious Materials ◽  
Drying Methods ◽  
Calorimetric Measurement ◽  
Balance Approach ◽  
Mass Balance Approach

The reactivity of supplementary cementitious materials (SCMs) is a key issue in the sustainability of cement-based materials. In this study, the effect of drying with isopropanol and acetone as well as the interpretation of thermogravimetric data on the results of an R3 test for evaluation of the SCM pozzolanic reaction were investigated. R3 samples consisting of calcium hydroxide, potassium hydroxide, potassium sulphate, water, and SCM were prepared. Besides silica fume, three different types of calcined clays were investigated as SCMs. These were a relatively pure metakaolin, a quartz-rich metakaolin, and a mixed calcined clay, where the amount of other types of clays was two times higher than the kaolinite content. Thermogravimetric analysis (TGA) was carried out on seven-day-old samples dried with isopropanol and acetone to stop the reaction processes. Additional calorimetric measurement of the R3 samples was carried out for evaluation of the reaction kinetics. Results show that drying with isopropanol is more suitable for analysis of R3 samples compared to acetone. The use of acetone results in increased carbonation and TGA mass losses until 40 (isothermal drying for 30 min) and 105 °C (ramp heating), indicating that parts of the acetone remain in the sample, causing problems in the interpretation of TGA data. A mass balance approach was proposed to calculate calcium hydroxide consumption from TGA data, while also considering the amount of carbonates in the sample and TGA data corrections of original SCMs. With this approach, an improvement of the linear correlation of TGA results and heat release from calorimetric measurement was achieved.

scholarly journals Influence of quartz powder and silica fume on the performance of Portland cement

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Ludmila Rodrigues Costa Tavares ◽  
Joaquim Francisco Tavares Junior ◽  
Leonardo Martins Costa ◽  
Augusto Cesar da Silva Bezerra ◽  
Paulo Roberto Cetlin ◽  
...  
Keyword(s):  
Portland Cement ◽  
Silica Fume ◽  
Electrical Resistance ◽  
Cementitious Materials ◽  
Pozzolanic Reaction ◽  
Heat Of Hydration ◽  
Supplementary Cementitious Materials ◽  
Cementitious Composites ◽  
Quartz Powder ◽  
Hydration Properties

AbstractSupplementary cementitious materials interact chemically and physically with cement, influencing the formation of hydrate compounds. Many authors have analyzed the filler and pozzolanic effect. However, few studies have explored the influence of these effects on hydration, properties in the fresh and hardened states, and durability parameters of cementitious composites separately. This study investigates the influence of the replacement of 20% of Portland cement for silica fume (SF) or a 20-µm medium diameter quartz powder (QP) on the properties of cementitious composites from the first hours of hydration to a few months of curing. The results indicate that SF is pozzolanic and that QP has no pozzolanic activity. The use of SF and QP reduces the released energy at early times to the control paste, indicating that these materials reduce the heat of hydration. The microstructure with fewer pores of SF compounds indicates that the pozzolanic reaction reduced pore size and binding capability, resulting in equivalent mechanical properties, reduced permeability and increased electrical resistance of the composites. SF and QP increase the carbonation depth of the composites. SF and QP composites are efficient in the inhibition of the alkali-aggregate reaction. The results indicate that, unlike the filler effect, the occurrence of pozzolanic reaction strongly influences electrical resistance, reducing the risk of corrosion of the reinforcement inserted in the concrete.

scholarly journals Effects after 1500 Hardening Days on the Microstructure and Durability-Related Parameters of Mortars Produced by the Incorporation of Waste Glass Powder as a Clinker Replacement

2021 ◽  
Vol 13 (7) ◽  
pp. 3979
Author(s):  
Rosa María Tremiño ◽  
Teresa Real-Herraiz ◽  
Viviana Letelier ◽  
Fernando G. Branco ◽  
José Marcos Ortega
Keyword(s):  
Diffusion Coefficient ◽  
Water Absorption ◽  
Glass Powder ◽  
Cementitious Materials ◽  
Cement Industry ◽  
Waste Glass ◽  
Supplementary Cementitious Materials ◽  
Chloride Diffusion ◽  
Chloride Diffusion Coefficient ◽  
Waste Glass Powder

One of the ways of lessening the CO2 emissions of cement industry consists of replacing clinkers with supplementary cementitious materials. The required service life of real construction elements is long, so it is useful to characterize the performance of these materials in the very long term. Here, the influence of incorporating waste glass powder as a supplementary cementitious material, regarding the microstructure and durability of mortars after 1500 hardening days (approximately 4 years), compared with reference mortars without additions, was studied. The percentages of clinker replacement by glass powder were 10% and 20%. The microstructure was studied using impedance spectroscopy and mercury intrusion porosimetry. Differential thermal and X-ray diffraction analyses were performed for assessing the pozzolanic activity of glass powder at the end of the time period studied. Water absorption after immersion, the steady-state diffusion coefficient, and length change were also determined. In view of the results obtained, the microstructure of mortars that incorporated waste glass powder was more refined compared with the reference specimens. The global solid fraction and pores volume were very similar for all of the studied series. The addition of waste glass powder reduced the chloride diffusion coefficient of the mortars, without worsening their behaviour regarding water absorption after immersion.

Pulse Velocity Measurements in Fly Ash Blended Cementitious Systems Containing 43 Grade Cement

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
V. M. Sounthararajan ◽  
A. Sivakumar
Keyword(s):  
Fly Ash ◽  
Cost Savings ◽  
Ultrasonic Pulse Velocity ◽  
Cementitious Materials ◽  
Ultrasonic Pulse ◽  
Pozzolanic Reaction ◽  
Pulse Velocity ◽  
Supplementary Cementitious Materials ◽  
Pozzolanic Material ◽  
Cementitious Systems

Investigations on the different supplementary cementitious materials based on the hardening properties and the optimized dosage in cementitious systems find the right choice of pozzolanic material. It is essential to combine various additive/admixtures in concrete in proper proportions to maximize the benefits resulting in cost savings in construction. In the recent years, production technology and composition of hydraulic cements affect the setting and early age behavior of cementitious material. The addition of fly ash in cement is one viable technology to derive maximum benefits in terms of the economy and improved pozzolanic reaction. Ultrasonic pulse velocity testing is a feasible method for evaluating the hardening properties of cementitious materials. In this study, an attempt was made to derive the engineering basis for understanding the development of hardness during hydration of fly ash (FA) based cementitious systems. The tests conducted using pulse velocity technique proved to be an effective method for characterizing the early strength gain properties of different cementitious systems.

Hydration Characteristics of Cement Paste Containing Supplementary Cementitious Materials

2012 ◽  
Vol 37 (3) ◽  
pp. 535-544 ◽  
Author(s):  
A. Elahi ◽  
Q. U. Z. Khan ◽  
S. A. Barbhuiya ◽  
P. A. M. Basheer ◽  
M. I. Russell
Keyword(s):  
Cement Paste ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Hydration Characteristics

scholarly journals The Relationship between Cementitious Composition and Properties of Ultrahigh Strength Concrete

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Dehui Wang ◽  
Zhiwen Zhang
Keyword(s):  
Fly Ash ◽  
Calcium Hydroxide ◽  
Silica Fume ◽  
Design Method ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Strength Concrete ◽  
Ultrahigh Strength ◽  
Acceleration Period ◽  
The Relationship

It is well known that supplementary cementitious materials (SCMs) have obvious effects on the properties of concrete. In order to understand the relationship between cementitious materials and properties of ultrahigh strength concrete (UHSC), the cementitious compositions of UHSC were designed by the simple-centroid design method. The effects of cementitious compositions on the properties of UHSC were investigated. It was found that the incorporation of silica fume (SF) improved the flowability and strength of UHSC, but it decreased the time of acceleration period, calcium hydroxide (CH) content, and porosity of UHSC at a certain content. The incorporation of fly ash (FA) increased the flowability, time of acceleration period, and porosity of UHSC, but it decreased the strength and CH content of UHSC. The relationships between cement, silica fume, and fly ash and the properties of UHSC were calculated based on the simple-centroid design method.

The Influence of Partial Substitution of Raw Materials with Heavy Ash on the Main Properties of Portland Cements

2018 ◽  
Vol 69 (4) ◽  
pp. 860-863 ◽  
Author(s):  
Carmen Oproiu ◽  
Georgeta Voicu ◽  
Adrian Ionut Nicoara ◽  
Alina Ioana Badanoiu
Keyword(s):  
Raw Materials ◽  
Bottom Ash ◽  
Cementitious Materials ◽  
Cement Industry ◽  
Raw Material ◽  
Supplementary Cementitious Materials ◽  
Partial Substitution ◽  
X Ray Diffraction ◽  
Binder Ratio ◽  
Water To Binder Ratio

The use of wastes in cement industry have impact both from economic and environmental point of views. Wastes can be used in clinker manufacture (to substitute raw materials or as alternative fuel) as well as supplementary cementitious materials in cement. This paper presents results regarding the use of heavy ash (bottom ash) as component of raw mix used for the clinker manufacture. Two types of cements were obtained by the milling of clinker produced with/without heavy ash (HA) as component of raw mix and gypsum (2%). The compressive strengths of these cements was assessed on plastic mortars (water:binder = 1:2 ratio and binder:aggregate = 1:3 ratio), cast in prismatic moulds (14x14x160 mm3), hardened different periods of time comprised between 1 to 28 days. The hydration and hardening processes which occur in the cementitious systems with/without waste content were assessed on pastes with water to binder ratio of 0.5, hardened for 1 up to 90 days. X-ray diffraction (XRD) and complex thermal analysis (DTA-TG) were used for pastes� characterization. The composition of clinker was assessed by XRD and microstructure by scanning electron microscopy (SEM). The results obtained in the framework of this research do not show any important difference between the clinkers� characteristics produced with alternative raw material (heavy ash) as compared with the ones produced with natural raw materials. Also, the properties of cements produced of these clinkers are similar.

Effects of Various Amounts of Natural Pozzolans from Volcanic Scoria on Performance of Portland Cement Mortars

2017 ◽  
Vol 32 ◽  
pp. 36-52 ◽  
Author(s):  
Willy Hermann Juimo Tchamdjou ◽  
Sophie Grigoletto ◽  
Frédéric Michel ◽  
Luc Courard ◽  
Toufik Cherradi ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Portland Cement ◽  
Mechanical Strength ◽  
Calcium Hydroxide ◽  
Supplementary Cementitious Materials ◽  
Strength Development ◽  
Natural Pozzolan ◽  
X Ray ◽  
Natural Pozzolans ◽  
Cement Mortars

The aim of this paper is to assess the possibility of using natural pozzolans (NPs) from Cameroonian volcanic scoria as supplementary cementitious materials (SCMs) in the production of Portland cement mortars. Four natural pozzolans (Black Natural Pozzolan: BNP, Dark-Red Natural Pozzolan: DRNP, Red Natural Pozzolan: RNP and Yellow Natural Pozzolan: YNP) with 3600, 4500, 4700 and 5200 cm2/g Blaine fineness respectively were produced from different colors (Black, Dark red, Red and Yellow) volcanic scoria in a laboratory mill. Natural pozzolans were characterized with regard to particle size distribution, particle shape, electrical conductivity, X-ray fluorescence (XRF) and X-ray diffraction (XRD). The calcium hydroxide consumption by NPs was assessed firstly by electrical conductivity measurements of calcium hydroxide/NPs suspensions with calcium hydroxide excess. Evidence of pozzolanic reactivity of NPs is revealed in hydrated lime pastes, and low reactivity was observed in aqueous suspensions. The effects of 15, 25, and 35 wt.% of NPs as cement substitution on the properties of Portland cement mortars were investigated. Different properties were studied such as setting time, consistency, mechanical strength, pozzolanic activity, absorption by capillarity and resistance to carbonation. The reactivity of NPs was also assessed by means of the mechanical strength development of mortars. The results obtained show that pozzolanic and hydraulic reactions take place in OPC systems. The correlation between mechanical strengths and physical properties of NPs has been established. The study concludes that using DRNP and RNP at 15 wt. % cement replacement can ameliorate globally the performance of mortar. Using all NPs at 35 wt. % has negative effect on the fundamental properties of cementitious mortars.

Sign in / Sign up

Export Citation Format

Share Document