Study on the Mix Proportion Design of C30 Supersulphated Phosphogysum-Slag Cement (SSC) Concrete

supersulphated phosphogysum-slag cement (SSC) is a newly developed non-burned cementitious material. It’s mixed and ground with 40%-50% phosphogypsum, 40%-50% ground granulated blast-furnace slag (GGBFS), 2% steel slag and 4% portland cement clinker. But the component of SSC differs greatly from that of Portland cement, there is few application researches about the SSC. In order to realize resourceful utilization of phosphogypsum, the mix proportion design method of SSC are studied. The mix proportion design method for C30 are systematically studied and a design optimization was carried out. According to the design regulations of mix proportion of ordinary concrete and the characteristics of SSC, the C30 high flowing concrete is prepared, and the optimum water-cement ratio is obtained based on revised Bowromi formula. According to the mix proportion optimization design, the 28d strength of SSC is up to 38.5MPa.

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Complex Shrinkage-Reducing Additives for Alkali Activated Slag Cement Fine Concrete

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.321.165 ◽

2021 ◽

Vol 321 ◽

pp. 165-170

Author(s):

Pavlо Krivenko ◽

Volodimir I. Gots ◽

Oleh Petropavlovskyi ◽

Igor Rudenko ◽

Oleksandr Konstantynovskyi

Keyword(s):

Cement Clinker ◽

Reinforcement Corrosion ◽

Sodium Gluconate ◽

Slag Cement ◽

Alkali Activated Slag ◽

Granulated Blast Furnace Slag ◽

Portland Cement Clinker ◽

Activated Slag ◽

Furnace Slag ◽

Alkali Activated

Optimization of complex shrinkage-reducing additives (further, SRA’s), consisting of ordinary portland cement clinker (further, OPC clinker), salt-electrolyte and surfactants, is provided for prevention of steel reinforcement corrosion due to shrinkage mitigation in alkali-activated slag cement (further, AASC) fine concrete. Modification of AASC by SRA included 0.3 % sodium lignosulphonate, 0.15 % sodium gluconate, 1.4 – 2.0 % NaNO3 and 6.5 - 7.7 % OPC clinker (by mass of granulated blast furnace slag) provides shrinkage reduction from 0.984 up to 0.560 – 0.605 mm/m (t=202 °С, R.H.=65 %). Unlike, SRA presented by the mentioned system with 1.50 - 1.59 % Na2SO4 and 4.0 - 4.65 % OPC clinker causes shrinkage mitigation from down to 0.625 - 0.640 mm/m. In addition, SRA with 1.80 - 2.05 % Na3PO4 and 4.0 - 4.6 % OPC clinker minimizes shrinkage to 0.713 - 0.700 mm/m. Shrinkage mitigation in modified AASC fine concrete is explained by less water, higher crystallinity of hydrated phases as well as by formation of minamiit (Na,Ca0.5)Al3(SO4)2(OH)6, calcium hydronitroaluminate ЗСаО∙А12О3∙Са (NO3)2∙10Н2О and calcium hydroxylapatite Са10(РО4)6(ОН)2 crystals versus salt-electrolyte, i.e. Na2SO4, NaNO3 and Na3PO4 agreeably. The 28 day compressive strength of modified AASC fine concrete is not less than the reference one (48.0 - 56.0 МPа).

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Influence of Steel Slag Type on Concrete Shrinkage

Sustainability ◽

10.3390/su13010214 ◽

2020 ◽

Vol 13 (1) ◽

pp. 214

Author(s):

Maria Dolores Rubio-Cintas ◽

Maria Eugenia Parron-Rubio ◽

Francisca Perez-Garcia ◽

António Bettencourt Ribeiro ◽

Miguel José Oliveira

Keyword(s):

Steel Slag ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

Cement Clinker ◽

Concrete Shrinkage ◽

Granulated Blast Furnace Slag ◽

Hydraulic Binder ◽

Portland Cement Clinker ◽

Different Characteristics ◽

Furnace Slag

Building construction and building operations have a massive direct and indirect effect on the environment. Cement-based materials will remain essential to supply the growth of our built environment. Without preventive measures, this necessary demand in cement production will imply a substantial increase in CO2 generation. Reductions in global CO2 emissions due to cement consumption may be achieved by improvements on two main areas: increased use of low CO2 supplementary cementitious materials and a more efficient use of Portland cement clinker in mortars and concretes. The use of ground granulated blast furnace slag in concrete, as cement constituent or as latent hydraulic binder, is a current practice, but information of concrete with ladle furnace slag is more limited. Specific knowledge of the behavior of mixtures with steel slag in relation to certain properties needs to be improved. This paper presents the results of the shrinkage (total and autogenous) of five concrete mixtures, produced with different percentages of two different slags in substitution of cement. The results show that shrinkage of concrete with the two different slags diverges. These different characteristics of the two materials suggest that their use in combination can be useful in optimizing the performance of concrete.

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Investigation of Mechanical Properties, Durability and Microstructure of Low-Clinker High-Performance Concretes Incorporating Ground Granulated Blast Furnace Slag, Siliceous Fly Ash and Silica Fume

Applied Sciences ◽

10.3390/app11020830 ◽

2021 ◽

Vol 11 (2) ◽

pp. 830

Author(s):

Katarzyna Konieczna ◽

Karol Chilmon ◽

Wioletta Jackiewicz-Rek

Keyword(s):

Compressive Strength ◽

Blast Furnace ◽

Fly Ash ◽

Blast Furnace Slag ◽

High Performance ◽

Cement Clinker ◽

Water Penetration ◽

Granulated Blast Furnace Slag ◽

Portland Cement Clinker ◽

Furnace Slag

The main assumption of eco-efficient High-Performance Concrete (HPC) design is the reduction of Portland cement clinker content without negatively affecting the composite’s mechanical and durability properties. In this paper, three low-clinker HPC mixtures incorporating slag cement (CEM III/B as per EN 197-1) and Supplementary Cementitious Materials (SCMs)—Ground Granulated Blast Furnace Slag (GGBFS), Siliceous Fly Ash (SFA) and Silica Fume (SF)—were designed. The maximum amount of Portland cement clinker from CEM III/B varied from 64 to 116 kg in 1 m3 of concrete mix. The compressive strength of HPC at 2, 7, 14, 28, 56, 90 days, and 2 years after casting, as well as the modulus of elasticity on 2-year-old specimens, was tested. The depth of water penetration under pressure and internal frost resistance in freeze–thaw tests were evaluated after 56 days of curing. Additionally, the concrete pH value tests were performed. The microstructure of 2-year-old HPC specimens was analyzed using Scanning Electron Microscopy (SEM). The research proved that it is possible to obtain low-clinker High-Performance Concretes that reach compressive strength of 76–92 MPa after 28 days of curing, show high values of modulus of elasticity (49–52 GPa) as well as increased resistance to frost and water penetration under pressure.

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Improving the Efficiency of Slag Portland Cement by Reducing Shrinkage Deformations

Materials Science Forum ◽

10.4028/www.scientific.net/msf.992.104 ◽

2020 ◽

Vol 992 ◽

pp. 104-110

Author(s):

Svetlana V. Samchenko ◽

D.A. Zorin

Keyword(s):

Portland Cement ◽

Compression Strength ◽

Cement Hydration ◽

Early Stage ◽

Cement Clinker ◽

Cement Stone ◽

Slag Cement ◽

Portland Cement Clinker ◽

Granulated Slag ◽

Portland Slag Cement

The influence of the artificial additive introduced at the joint grinding of granulated slag, Portland cement clinker and gypsum on the Portland slag cement hydration, its compression strength at an early stage and shrinkage deformation is investigated. It was found that in the presence of sulfoferrite clinker there is an amorphization of cement stone structure with formation of stone with high density and strength in early setting. The open porosity of the hardened paste is reduced by 13 – 15 % in comparison with plain Portland slag cement. The samples strength increases by 1.55 - 1.78 times at grade stage, by 15.5 - 19.4 % in bending and by 6.4 - 11.2 % in compression.

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Granulated Blast-Furnace Slag and Coal Fly Ash Ternary Portland Cements Optimization

Sustainability ◽

10.3390/su12145783 ◽

2020 ◽

Vol 12 (14) ◽

pp. 5783 ◽

Cited By ~ 2

Author(s):

Rosa Abnelia Rivera ◽

Miguel Ángel Sanjuán ◽

Domingo Alfonso Martín

Keyword(s):

Compressive Strength ◽

Blast Furnace ◽

Fly Ash ◽

Portland Cement ◽

Blast Furnace Slag ◽

Coal Fly Ash ◽

Cement Clinker ◽

Portland Cements ◽

Granulated Blast Furnace Slag ◽

Furnace Slag

Granulated blast-furnace slag (GBFS) and coal fly ash (CFA) are two well-known constituents in Portland cements. Ternary Portland cements (GBFS-CFA-K) provide environmental advantages by reducing Portland cement clinker (K) production and, therefore, promote lower CO2 emissions. Nevertheless, both of them cause a delay in the compressive strength gain. Given that, the early compressive strength for both constituents is low, but they improve the compressive strength at medium and later ages as consequence of the pozzolanic reaction. In this paper, a full factorial design with two levels was developed for the mortar compressive strength estimation at 2, 7 and 28 days. Mortar prisms made with 25% and 40% of granulated blast-furnace slag (GBFS) and/or coal fly ash (CFA) were tested. The effects of the interaction between GBFS and CFA on the compressive strength development of ternary Portland cement mortars were reported. Results show that the contribution of both cement constituents to the ternary mortar mix reduces the compressive strength for all the tested ages. Nevertheless, the finer the GBFS, the better ternary cement performance was achieved, showing that the synergistic effect is more effective when the finer GBFS is used, probably due to a more adequate particle size distribution. Finally, a relationship between compressive strength, fineness, GBFS content and CFA content was found for each age.

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Preparation of Low-Heat Portland Cement Clinker with Coal Gangue

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.306-307.861 ◽

2011 ◽

Vol 306-307 ◽

pp. 861-864

Author(s):

Guang Li Chen ◽

Xing Hua Fu ◽

Wen Hong Tao

Keyword(s):

Portland Cement ◽

Calcium Silicate ◽

Calcium Silicate Hydrate ◽

Raw Materials ◽

Coal Gangue ◽

Cement Clinker ◽

Mix Proportion ◽

Portland Cement Clinker ◽

Hydration Characteristics

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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Utilization of steel slag for Portland cement clinker production

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2007.07.093 ◽

2008 ◽

Vol 152 (2) ◽

pp. 805-811 ◽

Cited By ~ 278

Author(s):

P.E. Tsakiridis ◽

G.D. Papadimitriou ◽

S. Tsivilis ◽

C. Koroneos

Keyword(s):

Portland Cement ◽

Steel Slag ◽

Cement Clinker ◽

Portland Cement Clinker ◽

Clinker Production

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Calorimetric Studies of Alkali-Activated Blast-Furnace Slag Cements at Early Hydration Processes in the Temperature Range of 20–80 °С

Materials ◽

10.3390/ma14195872 ◽

2021 ◽

Vol 14 (19) ◽

pp. 5872

Author(s):

Aleksandr Usherov-Marshak ◽

Danutė Vaičiukynienė ◽

Pavel Krivenko ◽

Girts Bumanis

Keyword(s):

Blast Furnace ◽

Portland Cement ◽

Heat Release ◽

Structure Formation ◽

Blast Furnace Slag ◽

Cement Clinker ◽

Formation Stage ◽

Portland Cement Clinker ◽

Furnace Slag ◽

Alkali Activated

In the hydration process of inorganic cements, the analysis of calorimetric measurements is one of the possible ways to better understand hydration processes and to keep these processes under control. This study contains data from the study of thermokinetic processes in alkali-activated blast-furnace slag cements compared to ordinary Portland cement (OPC). The obtained results show that, in contrast to ОРС, the heat release values cannot be considered as a characteristic of the activity of alkali-activated blast-furnace slag cements. In addition, it is concluded that in the case of OPC cements, cumulative heat release is a criterion for the selection of effective curing parameters, while in the case of alkali-activated blast-furnace slag cements, a higher heat rate (which increases sharply with increasing temperature from 20 to 40 °С) is a criterion. From the point of views of thermokinetics, the rate of heat release at temperatures up to 40 °С can be a qualitative criterion that allows to choose the parameters of heat curing of alkali-activated cement concretes. By introducing a crystallo-chemical hardening accelerator, such as Portland cement clinker, into the composition of alkali-activated blast-furnace slag cements, it is possible to accelerate the processes not only in the condensation-crystallization structure formation stage, but also in the dispersion-coagulation structure formation stage. Portland cement clinker increased the efficiency of thermal curing at relatively non-high temperatures.

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