Effect of Ground Granulated Blast Furnace Slag, Pulverized Fuel Ash, Silica Fume on Sulfuric Acid Corrosion Resistance of Cement Matrix

The use of ordinary Portland cement as the primary binder in concrete production resulted in the high carbon footprint of the concrete material which cause a great deal of environmental impacts over the years. The consumption of OPC is especially significant for high strength concrete, which require a very high cement content (more than 450 kg/m3). Hence, supplementary cementitious materials such as ground granulated blast furnace slag (GGBS) and pulverized fuel ash (PFA) were chosen as partial replacement materials of OPC for concrete production in the research due to their ease of availability from the steelmaking manufacturing sectors and coal-fired electricity power stations in the country. As the sustainability of concrete is also our main concern, the durability performance of flowable high performance concrete containing high volume of GGBS and PFA (50-80% replacement of OPC) has been studied in this research. Therefore, the durability properties of flowable high performance concrete had been assessed in term of air permeability, porosity, water absorption and capillary action. From the results of assessment, all ternary blended concrete mixes exhibited better durability performances than control OPC concrete at later ages due to formation of denser microstructure by pozzolanic reaction of GGBS and PFA. It is concluded that the mix proportion of flowable high performance concrete production with 60% replacement of OPC by GGBS and PFA has the optimum durability performances than OPC concrete.

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Effects of ground granulated blast furnace slag and pulverized fuel ash on rheology of concrete

Nigerian Journal of Technology ◽

10.4314/njt.v39i1.10 ◽

2020 ◽

Vol 39 (1) ◽

pp. 97-104

Author(s):

A.S. Bature ◽

M. Khorami ◽

A. Lawan

Keyword(s):

Blast Furnace ◽

Portland Cement ◽

Yield Stress ◽

Blast Furnace Slag ◽

Granulated Blast Furnace Slag ◽

Fuel Ash ◽

Pulverized Fuel ◽

Dynamic Yield ◽

Pulverized Fuel Ash ◽

Furnace Slag

The rheology of concrete containing Pulverized Fuel Ash (PFA) and Ground Granulated Blast Furnace Slag (GGBS) has been scarcely studied and reported, despite their increase application as Supplementary Cementitious Materials (SCM) that drives improvement of sustainability of the construction industry. This work studied the effect of these SCMs and Superplasticizer proportions on rheological properties of concrete using rate controlled concrete rheometer. Two groups of mixes containing replacement or addition on mass basis using either PFA or GGBS or their combinations were derived from the control mix. The dynamic yield stress, plastic viscosity and 28 day compressive strength of the control mix are 1258 Pa, 6 PaS, and 40.5 MPa respectively. The results of the rheology tests of the various binary mixes (PFA and Portland cement) and ternary mixes (Portland cement, PFA and GGBS) structural concrete shows wide disparity in the measured rheological parameters. The results show that the decrease in dynamic yield stress of the ternary mix containing 20% GGBS is 4.1%, whereas the decrease in dynamic stress of the ternary mix containing 20% PFA is 35.9% compared to the control ternary mix. The high volume Portland cement replaced ternary concrete can therefore be effectively characterized as a workable and pumpable concrete. Keywords: Rheology, PFA, GGBS, superplasticizer, concrete.

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Cements in radioactive waste disposal: some mineralogical considerations

Mineralogical Magazine ◽

10.1180/minmag.1985.049.351.08 ◽

1985 ◽

Vol 49 (351) ◽

pp. 211-221 ◽

Cited By ~ 16

Author(s):

C. E. McCulloch ◽

M. J. Angus ◽

R. W. Crawford ◽

A. A. Rahman ◽

F. P. Glasser

Keyword(s):

Blast Furnace ◽

Radioactive Waste ◽

Blast Furnace Slag ◽

Radioactive Waste Disposal ◽

Composite Matrix ◽

Fuel Ash ◽

Pulverized Fuel ◽

Pulverized Fuel Ash ◽

Furnace Slag

AbstractCementitious matrices are being assessed for immobilization of radioactive wastes. This paper discusses some mineralogical aspects of cement chemistry and the uses of siliceous minerals as selective sorbants to enhance immobilization potential.Studies of sorption and leaching of caesium from pulverized fuel ash (PFA), blast furnace slag, tobermorite, xonotlite, and clinoptilolite are reported. The role of incorporation of these additives in cement and the effect on the nature of the composite matrix on caesium behaviour has been investigated. Specific mechanisms of the interaction of additives with highly alkaline cement environment are described. While slags, PFA, and clinoptilolite undergo reaction at different rates, tobermorite and xonotlite appear to be stable in cement.

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Time Depndence of pH in a Cementitious Repository

MRS Proceedings ◽

10.1557/proc-127-439 ◽

1988 ◽

Vol 127 ◽

Cited By ~ 8

Author(s):

Alan Atkinson ◽

Nicoia M. Everitt ◽

Richard M. Guppy

Keyword(s):

Blast Furnace ◽

Blast Furnace Slag ◽

Soluble Ions ◽

Fuel Ash ◽

Pulverized Fuel ◽

Waste Repository ◽

Pulverized Fuel Ash ◽

Furnace Slag ◽

Cement Compounds

ABSTRACTThe pH of a cementitious radioactive waste repository is expected to decrease with time as water leaches out soluble ions or as a result of reactions between repository constituents. These processes have been simulated in the laboratory and the results compared with behaviour anticipated from the known chemistry of cement compounds.The studies indicate that the pH in Portland cements and Blast Furnace Slag cements (BFS) is likely to remain above 10.5 for very long periods of time, of the order of several hundred thousand years for a typical repository. They also show that extensive use of Pulverized Fuel Ash (PFA) leads to uncertainty in long term pH which could be as low as 9 to 10 in some cases.

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Influence of Molarity and Chemical Composition on the Development of Compressive Strength in POFA Based Geopolymer Mortar

Advances in Materials Science and Engineering ◽

10.1155/2015/647071 ◽

2015 ◽

Vol 2015 ◽

pp. 1-15 ◽

Cited By ~ 19

Author(s):

S. M. Alamgir Kabir ◽

U. Johnson Alengaram ◽

Mohd Zamin Jumaat ◽

Afia Sharmin ◽

Azizul Islam

Keyword(s):

Compressive Strength ◽

Blast Furnace Slag ◽

Palm Oil Fuel Ash ◽

Manufactured Sand ◽

Granulated Blast Furnace Slag ◽

Mix Proportion ◽

Geopolymer Matrix ◽

Fuel Ash ◽

Oil Fuel ◽

Furnace Slag

The investigation concerns the use of the optimum mix proportion of two locally available pozzolanic waste materials, namely, ground granulated blast furnace slag (GGBS) and palm oil fuel ash (POFA), together with metakaolin (MK) as binders. In addition, another local waste material, manufactured sand (M-sand), was used as a replacement for conventional sand in the development of green geopolymer mortar. Twenty-four mortar mixtures were designed with varying binder contents and alkaline activators. The oven dry curing was also kept consistent for all the mix proportions at a temperature of 65°C for 24 hours. The highest 28-day compressive strength of about 48 MPa was obtained for the mortar containing 20% of MK, 35% of GGBS, and 45% of POFA. The increment of MK beyond 20% leads to reduction of the compressive strength. The GGBS replacement beyond 35% also reduced the compressive strength. The entire specimen achieved average 80% of the 28-day strength at the age of 3 days. The density decreased with the increase of POFA percentage. The finding of this research by using the combination of MK, GGBS, and POFA as binders to wholly replace conventional ordinary Portland cement would lead to alternate eco-friendly geopolymer matrix.

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Durability Performance of Cement Composites Containing Ground Granulated Blast Furnace Slag

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1105.26 ◽

2015 ◽

Vol 1105 ◽

pp. 26-30

Author(s):

Martina Kovalcikova ◽

Adriana Eštoková ◽

Alena Luptáková

Keyword(s):

Blast Furnace ◽

Blast Furnace Slag ◽

Calcium Release ◽

Experimental Studies ◽

Concrete Mixture ◽

Cement Matrix ◽

Acidithiobacillus Thiooxidans ◽

Granulated Blast Furnace Slag ◽

Calcium Compounds ◽

Furnace Slag

The hydraulic properties of granulated blast-furnace slags have been studied for nearly 200 years, and use of slag in mortars and concretes dates back more than a hundred years. The use of ground blast furnace slag, added as a replacement for a portion of the portland cement, has gained increasing acceptance in recent years. The effects of sulphur-oxidizing bacteria Acidithiobacillusthiooxidans on concrete mixture with addition of ground granulated blast furnace slag compared to mixture without any additives were investigated in laboratory over a period of 91 days. A laboratory study was conducted to comparison the performance of concrete samples in terms of a concrete deterioration influenced by the leaching of calcium compounds from the cement matrix. The changes in the elemental concentrations of calcium ions in leachates were measured by using X – ray fluorescence method. Experimental studies confirmed: bacteria Acidithiobacillus thiooxidans caused much intensive calcium release from the concrete matrices into the solution; the higher resistance of concrete mixture with 65 % wt. slag addition was not confirmed.

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