scholarly journals Experimental verification of shrinkage due to drying in concrete under varying humidity conditions in accordance with the Eurocode2 standard

2018 ◽  
Vol 49 ◽  
pp. 00084 ◽  
Author(s):  
Wioletta Raczkiewicz ◽  
Magdalena Bacharz
Keyword(s):  
Blast Furnace ◽  
Relative Humidity ◽  
Experimental Verification ◽  
Blast Furnace Slag ◽  
Experimental Results ◽  
Computational Results ◽  
Concrete Shrinkage ◽  
Eurocode 2 ◽  
The Impact ◽  
Furnace Slag

The concrete shrinkage depends on many factors. There are the concrete mixture, dimensions of the element and environment conditions, mainly humidity. All these factors can be imposed under laboratory conditions and controlled. In field conditions, however, a constant humidity is not possible to keep. The paper presents the impact of relative humidity changes on the values of shrinkage strains. The experimental results obtained on the specimens (with size 150x150x600 mm) were compared with the values calculated in accordance with the Eurocode 2 standard. The specimens were made with basalt aggregate without admixtures or additives. Two kinds of cement were used in preparing the specimens: Portland and blast-furnace slag cement. All specimens were treated in water for 10 days in the first days after demoulding and then subjected to testing. During the 56 days the temperature was 22 ± 2°C, while the humidity decreased proportionally from 91% to 47%. Strains were measured and the specimens were weighed to determine the mass loss. The experimental results were compared to the computational results. It should be concluded that they were not coherent in the case of ambient humidity exceeding 80% although it was accordance with the Eurocode 2 standard.

scholarly journals Application areas of phosphogypsum in production of mineral binders and composites based on them: a review of research results

2018 ◽  
Vol 149 ◽  
pp. 01012 ◽  
Author(s):  
Leonid Dvorkin ◽  
Nataliya Lushnikova ◽  
Mohammed Sonebi
Keyword(s):  
Mechanical Properties ◽  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Setting Time ◽  
Industrial Wastes ◽  
Cement Clinker ◽  
Complete Replacement ◽  
Slaked Lime ◽  
The Impact ◽  
Furnace Slag

The increase of the consumption of gypsum products in construction industry with a limited amount of natural gypsum deposits requires alternative sources of gypsum-containing raw materials. In some countries which have fertilizers industry plants, the problem can be solved using industrial wastes, e.g. phosphorgypsum – a byproduct of fertilizers’ production. Kept in dumps over decades, phosphorgypsum is subjected to the chemical changes due to washing out impurities with rain and other natural factors. However, there are observed deviations of harmful impurities in dumped PG depending on its age., Phosphorgypsum of any age requires chemical treatment to neutralize remains of phosphorus and sulfuric acids, fluorine compounds. According to our researches one of the most simple and effective method of neutralization the impurities is using lime-containing admixtures. The paper presents results of laboratory tests of phosphorgypsum as a component of clinker and non-clinker binders. There were investigated the impact of phosphorgypsum as admixture for clinker binders to substitute natural gypsum. Neutralized phosphorgypsum can be applied as mineralizing admixture in calcination of Portland cement clinker. Adding 2 to 2.5% of phosphorgypsum as setting time regulator resulted in a similar physical and mechanical properties compared to mix made with natural gypsum. Another important area of phosphorgypsum application is sulphate activatoion of low-clinker blast-furnace slag cement (clinker content is less than 19%). According to results, the incorporation of phosphorgypsum as sulphate activator in cement has the better effect as natural gypsum. Other development has been carried out to modify the phosphorgypsum binder properties. Complex additive consisted of polycarboxylate-based superplasticizer and slaked lime permitted an increase mechanical properties of hardened phosphorgypsum binder due to significant a reduction of water consumption. Such modified binder can be used as partial or complete replacement of gypsum binder for filling cements and finishing plasters. It can substitute gypsum in non-clinker binders like supersulphated cements. There were also developed compositions of supersulphated cements based on low-alumina blast furnace slag and phosphorgypsum. Supersulphated cements were tested in normal-weight and light-weight concrete.

Effects of blast furnace slag and steel fiber on the impact resistance of railway prestressed concrete sleepers

2019 ◽  
Vol 99 ◽  
pp. 151-164
Author(s):  
Doo-Yeol Yoo ◽  
Jin-Young Lee ◽  
Hyun-Oh Shin ◽  
Jun-Mo Yang ◽  
Young-Soo Yoon
Keyword(s):  
Blast Furnace ◽  
Prestressed Concrete ◽  
Blast Furnace Slag ◽  
Steel Fiber ◽  
Impact Resistance ◽  
The Impact ◽  
Furnace Slag

scholarly journals Potential of Industrial By-Products as Liming Materials and Digestate as Organic Fertilizer and Their Effect on Soil Properties and Yield of Alfalfa (Medicago sativa L.)

2021 ◽  
Vol 13 (19) ◽  
pp. 11016
Author(s):  
Vladimir Ivezić ◽  
Vladimir Zebec ◽  
Brigita Popović ◽  
Meri Engler ◽  
Tihana Teklić ◽  
...  
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Organic Fertilizer ◽  
Acid Soils ◽  
Nutrient Status ◽  
Field Trials ◽  
Wood Ash ◽  
The Impact ◽  
Furnace Slag ◽  
By Products

Acid soils with pH values below 5.5 have a negative effect on agricultural production. For this reason, liming is applied as a measure to raise the soil pH to the optimum (pH = 6–7). The aim of our research was to evaluate and compare the effectiveness of four liming materials (wood ash from biomass powerplant, filter dust from cement factory, blast furnace slag from iron factory, and carbocalk (limestone, a by-product from a sugar factory)) in combination with and without solid digestate (a by-product from biogas plant) as organic fertilizer. Two field trials were set up to determine the effect of the studied materials to neutralize the acidity, and the impact on soil fertility and nutrient status in the soil. The results showed that all four liming materials raised the pH of the soil. Out of these four, wood ash showed to be the best while blast furnace slag was the worst. The yield of alfalfa increased with the application of all four lime materials. Application of liming materials with solid digestate increased soil organic matter and had slightly higher yields compared to liming materials without solid digestate. The highest yields were achieved with the application of wood ash, probably due to somewhat higher concentrations of potassium and phosphorus in wood ash. Further research on the financial aspects of investigated by-products application is necessary to exploit their potential as a liming material.

scholarly journals Effect of Ground Granulated Blast Furnace Slag Replacement Ratio on Structural Performance of Precast Concrete Beams

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7159
Author(s):  
Yong-Jun Lee ◽  
Hyeong-Gook Kim ◽  
Kil-Hee Kim
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Concrete Beams ◽  
Precast Concrete ◽  
Experimental Results ◽  
Structural Performance ◽  
Replacement Ratio ◽  
Granulated Blast Furnace Slag ◽  
The Mean ◽  
Furnace Slag

This study was conducted to investigate the effect of ground granulated blast furnace slag on the structural performance of precast concrete beams, evaluating the flexural, shear and bonding performance by using the replacement ratio of the ground granulated blast furnace slag as a variable. The design strength of the concrete was set at 45 MPa in consideration of the characteristics of precast concrete products, and the replacement ratio of the ground granulated blast furnace slag to replace cement was 30 to 70%. The experimental results showed that all specimens had similar behavioral characteristics regardless of the replacement ratio of the ground granulated blast furnace slag. Comparison of the prediction results obtained by ACI 318-19 and EC 2 showed that the mean flexural strength and shear strength were higher than 1.19 and 1.43, respectively, and the mean bond strength was 1.57, satisfying the required performance. Therefore, the experimental results showed that in using the ground granulated blast furnace slag as an admixture for precast concrete, the cement replacement ratio may be increased up to 70% without causing any problems in securing the structural performance. Summarizing the results of the present study, a ground granulated blast furnace slag replacement ratio of 50% or lower may be reasonably applied.

Optimization Chemical Composition of the Blast Furnace Slag with Uniform Design

2013 ◽  
Vol 743-744 ◽  
pp. 210-215 ◽  
Author(s):  
Hui Wang ◽  
Su Ping Cui ◽  
Xiao Long Shang
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Raw Materials ◽  
Design Method ◽  
Uniform Design ◽  
Significance Test ◽  
Glass Content ◽  
Granulated Blast Furnace Slag ◽  
The Impact ◽  
Furnace Slag

Using the industrial limestone, fly ash and pure chemical reagents as raw materials, the blast furnace slag was prepared in the simulation condition of the actual slag-making process. Using uniform design method, the influence of blast furnace slag composition factors such as quaternary alkalinity, ratio of CaO/MgO and ratio of SiO2/Al2O3 on the glass content of blast furnace slag were studied in the present in investigation, the relationship between glass content and the various factors has been obtained through regression analysis, and the main influence factors and the optimum blast furnace slag compositions been found out. The results showed that, the impact of various factors on the glass content of granulated blast furnace slag was quaternary alkalinity > ratio of SiO2/Al2O3 > ratio of CaO/MgO. According to the significance test of the regression equation and the verification experiment, it was concluded that the optimum compositions of granulated blast furnace slag were: the quaternary alkalinity was 0.85, the ratios of CaO/MgO and SiO2/Al2O3 were 11.5 and 6.5 respectively, and in this condition, the glass content of granulated blast furnace slag reached to 98.47%.

Investigation of Drilling Fluids Containing Blast Furnace Slag for Their Potential Impact on Formation Damage—A Laboratory Study

1999 ◽  
Vol 121 (3) ◽  
pp. 149-153 ◽  
Author(s):  
U. A. Tare ◽  
N. E. Takach ◽  
S. Z. Miska ◽  
F. B. Growcock ◽  
N. Davis
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Filter Cake ◽  
Drilling Fluid ◽  
Rapid Development ◽  
Formation Damage ◽  
Drilling Fluids ◽  
Filter Cakes ◽  
The Impact ◽  
Furnace Slag

This work discusses the effect of incorporating blast furnace slag (BFS) as an additive in water-based drilling fluids. The intent of this treatment is rapid development of a thin, impervious, and easily removable filter cake, thereby minimizing detrimental impact of the drilling fluid on formation productivity as opposed to previous applications of BFS in universal fluids. To evaluate the impact of BFS on filter cake properties, permeability plugging apparatus (PPA) tests and dynamic formation damage (DFD) studies were conducted. Drill-in fluids and dispersed muds were tested using varying quantities of BFS. Once a steady rate of dynamic filter cake deposition was achieved, the BFS in the filter cakes was chemically activated. The results obtained from these activation studies were compared with those obtained with no BFS and with unactivated BFS. The nature of the filter cakes was examined with an environmental scanning electron microscope (ESEM). Results obtained from the PPA tests indicate substantial decreases in initial spurt loss and filtrate volume with increasing concentration of BFS. The DFD studies substantiate the aforementioned observations and show enhancement of return permeabilities with BFS activation. ESEM studies demonstrate that BFS can consolidate filter cakes.

Characterization of Carbonatation Rate of Alkali-Activated Blast Furnace Slag in Various Environments

2021 ◽  
Vol 325 ◽  
pp. 40-46
Author(s):  
Richard Dvořák ◽  
Petr Hrubý ◽  
Libor Topolář
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Destructive Testing ◽  
Time Intervals ◽  
Impact Echo ◽  
The Impact ◽  
Non Destructive ◽  
Furnace Slag ◽  
Alkali Activated

Carbonatation represents one of the potential degradation processes whose can negatively affect the service life of constructions based on the inorganic binders. The carbonatation depth of the constructions when exposed to various environments is significantly dependent on the existing conditions. The most crucial parameters are the partial pressure of carbon dioxide and humidity. There were selected four environments for the deposition of samples made of the alkali-activated blast furnace slag mortars (exterior, interior, water and CO2 chamber) in this study. These types of environments guarantee the variation of desired parameters influencing the carbonatation rate. The progress of carbonatation was evaluated with a selected technique in time intervals of 28; 56 and 84 days of the sample's exposition to the selected environments. The characterization was done using the destructive techniques (compressive and flexural strength, phenolphthalein method) as well as the non-destructive one like the Impact-Echo or the Ultrasound time passage measurement. The combination of these techniques allows to determine and evaluate the progress of carbonation without the destructive testing of the samples which is necessary for the real applications of these materials.

Numerical Simulation of Internal Flow Field in Blast Furnace Slag Dry Granulating Device

2019 ◽  
Vol 944 ◽  
pp. 1199-1207
Author(s):  
Rui Yun Wang ◽  
Jin Yu Yin ◽  
Su Ping Cui
Keyword(s):  
Numerical Simulation ◽  
Blast Furnace ◽  
Flow Field ◽  
Blast Furnace Slag ◽  
Internal Flow ◽  
Simulation Method ◽  
Cooling Effectiveness ◽  
Field Uniformity ◽  
The Impact ◽  
Furnace Slag

In this paper, CFD numerical simulation method was adopted to study the internal flow field of experimental dry granulating device of blast furnace slag and to research the impact of equipment structure and wind speed on cooling effectiveness. Main content included the internal flow field uniformity under different blade type and number of inlets. The results showed that the internal flow field in strip-blades device was more uniform than fan-shaped blades device. With the increase of air inlets quantity, the internal flow field in device became more uniform and stable, especially when there were 8 air inlets in the equipment.

The Impact of In Situ-Formed Spinel on the Porosity of No-Cement Refractory Castables

2017 ◽  
Vol 908 ◽  
pp. 139-144
Author(s):  
Lenka Nevřivová
Keyword(s):  
Corrosion Resistance ◽  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Corrosion Test ◽  
Corundum Refractory ◽  
Refractory Castables ◽  
The Impact ◽  
Furnace Slag

The paper focuses on the determination of how in-situ formed magnesia-alumina spinel (MA spinel) content in corundum refractory castables influences the final properties and pore size distribution of no-cement refractory castables. The motivation for this research was the continued pressure on increasing the utility properties of refractory castables, namely their corrosion resistance to blast-furnace slag. The influence of MA spinel content was observed in vibration-compacted refractory castables (three mixtures). The corrosion test was performed to determine the dependence of the size of the slag-penetrated area on MA spinel content in the specimen. The pore structure of a slag-penetrated NCC and an unaffected castable was described.

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