Effect of micro silica and ground granulated blast furnace slag on performance of rubberized mortar

Aerated concrete (AC), such as cellular concrete, autoclaved aerated concrete (AAC), and non-autoclaved aerated concrete (NAAC), having excellent insulation properties, is commonly used in buildings located in cold regions, such as Nur-Sultan in Kazakhstan, the second coldest capital city in the world, because it can contribute to a large energy saving. However, when the AC is directly exposed to the repeated freeze and thaw (F-T) cycles, its F-T resistance can be critical because of lower density and scaling resistance of the AC. Moreover, the evaluation of the F-T resistance of the AC based on the durability factor (DF) calculated by using the relative dynamic modulus of elasticity may overestimate the frost resistance of the AC due to the millions of evenly distributed air voids in spite of its weak scaling resistance. In the present study, the F-T resistance of NAAC mixtures with various binary or ternary combinations of ground granulated blast-furnace slag (GGBFS) and micro-silica was assessed mainly using the ASTM C 1262/C1262M-16 Standard Test Method for Evaluating the Freeze-Thaw Durability of Dry-Cast Segmental Retaining Wall Units and Related Concrete Units. Critical parameters to affect the F-T resistance performance of the NAAC mixture such as compressive strength, density, water absorption, air–void ratio (VR), moisture uptake, durability factor (DF), weight loss (Wloss), the degree of saturation (Sd), and residual strength (Sres) were determined. Based on the determined parameter values, frost resistance number (FRN) has been developed to evaluate the F-T resistance of the NAAC mixture. Test results showed that all NAAC mixtures had good F-T resistance when they were evaluated with DF. Binary NAAC mixtures generally showed higher Sd and Wloss and lower DF and Sres than those of ternary NAAC mixtures. It was determined that the Sd was a key factor for the F-T resistance of NAAC mixtures. Finally, the developed FRN could be an appropriate tool to evaluate the F-T resistance of the NAAC mixture.

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Research in the Effect of Water-Cement Ratio on Strength of Fine Concretes with a Filler of Granulated Blast Furnace Slag

Stroitel nye Materialy ◽

10.31659/0585-430x-2018-760-6-20-23 ◽

2018 ◽

Vol 760 (6) ◽

pp. 20-23

Author(s):

N.V. KUZNETSOVA ◽

◽

А.I. DUBROVIN ◽

V.A. EZERSKIY ◽

◽

...

Keyword(s):

Blast Furnace ◽

Blast Furnace Slag ◽

Cement Ratio ◽

Water Cement Ratio ◽

Effect Of Water ◽

Granulated Blast Furnace Slag ◽

Furnace Slag

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The Influence of the Properties of the Material Used for Obtaining Geopolymers on Their Structure and Compressive Strength

Revista de Chimie ◽

10.37358/rc.17.6.5638 ◽

2017 ◽

Vol 68 (6) ◽

pp. 1182-1187

Author(s):

Ilenuta Severin ◽

Maria Vlad

Keyword(s):

Compressive Strength ◽

Blast Furnace ◽

Wheat Straw ◽

Red Mud ◽

Blast Furnace Slag ◽

Complex Structure ◽

Point Of View ◽

Granulated Blast Furnace Slag ◽

Furnace Slag ◽

Straw Ash

This article presents the influence of the properties of the materials in the geopolymeric mixture, ground granulated blast furnace slag (GGBFS) + wheat straw ash (WSA) + uncalcined red mud (RMu), and ground granulated blast furnace slag + wheat straw ash + calcined red mud (RMc), over the microstructure and mechanical properties of the synthesised geopolymers. The activation solutions used were a NaOH solution with 8M concentration, and a solution realised from 50%wt NaOH and 50%wt Na2SiO3. The samples were analysed: from the microstructural point of view through SEM microscopy; the chemical composition was determined through EDX analysis; and the compressive strength tests was done for samples tested at 7 and 28 days, respectively. The SEM micrographies of the geopolymers have highlighted a complex structure and an variable compressive strength. Compressive strength varied from 24 MPa in the case of the same recipe obtained from 70% of GGBFS + 25% WSA +5% RMu, alkaline activated with NaOH 8M (7 days testing) to 85 MPa in the case of the recipe but replacing RMu with RMc with calcined red mud, alkaline activated with the 50%wt NaOH and 50%wt Na2SiO3 solution (28 days testing). This variation in the sense of the rise in compressive strength can be attributed to the difference in reactivity of the materials used in the recipes, the curing period, the geopolymers structure, and the presence of a lower or higher rate of pores, as well as the alkalinity and the nature of the activation solutions used.

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Effect of Flue Gas Desulfurization Gypsum on the Properties of Calcium Sulfoaluminate Cement Blended with Ground Granulated Blast Furnace Slag

Materials ◽

10.3390/ma14020382 ◽

2021 ◽

Vol 14 (2) ◽

pp. 382 ◽

Cited By ~ 1

Author(s):

Danying Gao ◽

Zhenqing Zhang ◽

Yang Meng ◽

Jiyu Tang ◽

Lin Yang

Keyword(s):

Blast Furnace ◽

Mechanical Strength ◽

Flue Gas ◽

Blast Furnace Slag ◽

Setting Time ◽

Flue Gas Desulfurization ◽

Calcium Sulfoaluminate Cement ◽

Calcium Sulfoaluminate ◽

Granulated Blast Furnace Slag ◽

Furnace Slag

This work aims to investigate the effect of additional flue gas desulfurization gypsum (FGDG) on the properties of calcium sulfoaluminate cement (CSAC) blended with ground granulated blast furnace slag (GGBFS). The hydration rate, setting time, mechanical strength, pore structure and hydration products of the CSAC-GGBFS mixture containing FGDG were investigated systematically. The results show that the addition of FGDG promotes the hydration of the CSAC-GGBFS mixture and improves its mechanical strength; however, the FGDG content should not exceed 6%.

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Effect of Mineral Admixtures on the Performance of Low-Quality Recycled Aggregate Concrete

Crystals ◽

10.3390/cryst11060596 ◽

2021 ◽

Vol 11 (6) ◽

pp. 596

Author(s):

Yasuhiro Dosho

Keyword(s):

Blast Furnace ◽

Fly Ash ◽

Blast Furnace Slag ◽

Recycled Aggregate Concrete ◽

Recycled Aggregate ◽

Mineral Admixtures ◽

Structural Concrete ◽

Aggregate Concrete ◽

Granulated Blast Furnace Slag ◽

Furnace Slag

To improve the application of low-quality aggregates in structural concrete, this study investigated the effect of multi-purpose mineral admixtures, such as fly ash and ground granulated blast-furnace slag, on the performance of concrete. Accordingly, the primary performance of low-quality recycled aggregate concrete could be improved by varying the replacement ratio of the recycled aggregate and using appropriate mineral admixtures such as fly ash and ground granulated blast-furnace slag. The results show the potential for the use of low-quality aggregate in structural concrete.

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Control of the setting reaction and strength development of slag-blended volcanic ash-based phosphate geopolymer with the addition of boric acid

Journal of the Australian Ceramic Society ◽

10.1007/s41779-021-00610-4 ◽

2021 ◽

Author(s):

Jean Noël Yankwa Djobo ◽

Dietmar Stephan

Keyword(s):

Blast Furnace ◽

Boric Acid ◽

Blast Furnace Slag ◽

Volcanic Ash ◽

Strength Development ◽

Main Process ◽

Reaction Products ◽

Setting Times ◽

Granulated Blast Furnace Slag ◽

Furnace Slag

AbstractThis work aimed to evaluate the role of the addition of blast furnace slag for the formation of reaction products and the strength development of volcanic ash-based phosphate geopolymer. Volcanic ash was replaced by 4 and 6 wt% of ground granulated blast furnace slag to accelerate the reaction kinetics. Then, the influence of boric acid for controlling the setting and kinetics reactions was also evaluated. The results demonstrated that the competition between the dissolution of boric acid and volcanic ash-slag particles is the main process controlling the setting and kinetics reaction. The addition of slag has significantly accelerated the initial and final setting times, whereas the addition of boric acid was beneficial for delaying the setting times. Consequently, it also enhanced the flowability of the paste. The compressive strength increased significantly with the addition of slag, and the optimum replaced rate was 4 wt% which resulted in 28 d strength of 27 MPa. Beyond that percentage, the strength was reduced because of the flash setting of the binder which does not allow a subsequent dissolution of the particles and their precipitation. The binders formed with the addition of slag and/or boric acid are beneficial for the improvement of the water stability of the volcanic ash-based phosphate geopolymer.

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