scholarly journals Durability of Alkali-Activated Blast Furnace Slag Concrete: Chloride Ions Diffusion

2015 ◽  
Vol 30 (4) ◽  
pp. 120-127 ◽  
Author(s):  
Hong Ki Nam ◽  
Park Jae Kyu ◽  
Jung Kyu San ◽  
Han Sang Hun ◽  
Kim Jae Hyun
Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2817
Author(s):  
Gui-Yu Zhang ◽  
Yong-Han Ahn ◽  
Run-Sheng Lin ◽  
Xiao-Yong Wang

Every year, ceramic tile factories and the iron smelting industry produce huge amounts of waste ceramic tiles and blast furnace slag (BFS), respectively. In the field of construction materials, this waste can be used as a raw material for binders, thus reducing landfill waste and mitigating environmental pollution. The purpose of this study was to mix waste ceramic powder (WCP) into BFS paste and mortar activated by sodium silicate and sodium hydroxide to study its effect on performance. BFS was partially replaced by WCP at the rate of 10–30% by weight. Some experimental studies were conducted on, for example, the fluidity, heat of hydration, compressive strength testing, ultrasonic pulse velocity (UPV), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), electrical resistivity, sulfuric acid attack, and chloride ion diffusion coefficient. Based on the results of these experiments, the conclusions are: (1) increasing the amount of waste ceramic powder in the mixture can improve the fluidity of the alkali-activated paste; (2) adding waste ceramic powder to the alkali-activated mortar can improve the resistance of the mortar to sulfuric acid; (3) adding waste ceramic powder to the alkali-activated mortar can increase the diffusion coefficient of chloride ions; (4) the early strength of alkali-activated mortar is affected by the Ca/Si ratio, while the later strength is affected by the change in the Si/Al ratio.


2021 ◽  
Vol 325 ◽  
pp. 131-136
Author(s):  
Iveta Plšková ◽  
Petr Hrubý ◽  
Libor Topolář ◽  
Michal Matysík

The paper summarizes partial results of a study of degradation of materials based on alkali-activated blast-furnace slag (AAS) and comparative on cement CEM III/A 32.5 R after exposure to aggressive environments. It further specifies the possibilities for utilising destructive and non-destructive techniques to determine the progress of degradation and characterizes the degree of their correlation. After 28 days of ageing in a water environment, the produced test specimens (40×40×160 mm beams) were placed in aggressive media (ammonium nitrate solutions; sodium sulfate, rotating water) and after subsequent 28, 56 and 84 days of degradation were subjected to testing. Testing comprised both a destructive form (determination of compressive strength and flexural strength) and a selected non-destructive technique (Impact-echo method). The partial outputs were supplemented by the results acquired from monitoring weight changes. In addition, the development of Ultrasonic Pulse Velocity in relation to the progress of the degradation processes was also monitored. While the exposure of both test specimens to water and sodium sulfate did not result in any significant changes, the exposure to the ammonium nitrate solution exhibited rapid signs of degradation associated with a significant reduction in functional characteristics.


2013 ◽  
Vol 44 ◽  
pp. 607-614 ◽  
Author(s):  
O. Burciaga-Díaz ◽  
M.R. Díaz-Guillén ◽  
A.F. Fuentes ◽  
J.I. Escalante-Garcia

2021 ◽  
Vol 13 (20) ◽  
pp. 11298
Author(s):  
Alessio Occhicone ◽  
Mira Vukčević ◽  
Ivana Bosković ◽  
Claudio Ferone

The aluminum Bayer production process is widespread all over the world. One of the waste products of the Bayer process is a basic aluminosilicate bauxite residue called red mud. The aluminosilicate nature of red mud makes it suitable as a precursor for alkali-activated materials. In this work, red mud was mixed with different percentages of blast furnace slag and then activated by sodium silicate solution at different SiO2/Na2O ratios. Obtained samples were characterized by chemical–physical analyses and compressive strength determination. Very high values of compressive strength, up to 50 MPa, even for high percentage of red mud in the raw mixture (70 wt.% of RM in powder mixture), were obtained. In particular, the higher compressive strength was measured for cubic samples containing 50 wt.% of RM, which showed a value above 70 MPa. The obtained mixtures were characterized by no or scarce environmental impact and could be used in the construction industry as an alternative to cementitious and ceramic materials.


2016 ◽  
Vol 116 ◽  
pp. 63-71 ◽  
Author(s):  
J.L. Vilaplana ◽  
F.J. Baeza ◽  
O. Galao ◽  
E.G. Alcocel ◽  
E. Zornoza ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document