scholarly journals SELECTION OF A RATIONAL RECIPE OF LIGHTWEIGHT CONCRETE ON A MIXTURE OF CERAMSITE GRAVEL, NATURAL CRUSHED STONE AND GRANULAR SLAG

Author(s):  
A. Chernil'nik ◽  
D. El'shaeva ◽  
Y. Zherebtsov ◽  
N. Dotsenko ◽  
M. Samofalova

In conditions of dense urban development and a variety of engineering and geological conditions, the use of concretes with a combined aggregate of a rationally selected composition will solve the existing problem of reducing the mass of reinforced concrete structures of buildings and structures and maintaining the required strength and deformability. In this paper, studies have been carried out on the choice of a rational formulation of lightweight concrete based on expanded clay gravel, natural crushed stone and granulated blast furnace slag by varying the volume content of porous coarse aggregate and the volume content of fine aggregate in relation to the mixture. In total, 9 series of prototypes and 1 series of control samples are manufactured and tested. One series of samples includes three cubes with dimensions of 10x10x10 cm. All samples are tested in terms of density and compressive strength, the coefficient of constructive quality is determined. The results of the study shows that the introduction of expanded clay gravel into the composition of heavy concrete instead of part of the dense coarse aggregate and the replacement of the fine dense aggregate with granular blast furnace slag leads to an increase in the structural quality factor, that is, a decrease in the compressive strength of concrete is compensated for by an even more significant decrease in the density of the material, and means weight reduction. The increase in the coefficient of constructive quality of concrete based on expanded clay gravel, natural crushed stone and granulated blast-furnace slag in comparison with the control composition is 15.6 %.

2021 ◽  
Vol 2124 (1) ◽  
pp. 012017
Author(s):  
L R Mailyan ◽  
S A Stel’makh ◽  
E M Shcherban’ ◽  
D A Stroev

Abstract In the difficult conditions of modern construction, the use of concretes with a combined aggregate, if the composition is rational and the formulation and technological factors act rationally, will allow solving many existing problems. In this paper, studies were carried out on the choice of a rational formulation of lightened concrete based on foamed slag, natural crushed stone and granulated blast furnace slag by varying the volume content of a porous coarse aggregate and a fine aggregate in relation to the volume of the mixture. In total, 9 series of prototypes and 1 series of control samples were manufactured and tested. One series of samples includes three cubes with dimensions of 10x10x10 cm. All samples are tested for density, compressive strength and the coefficient of constructional quality. According to the results of the study, it was concluded that the introduction of foamed slag into the composition of heavy concrete instead of a part of a dense coarse aggregate and the replacement of a fine dense aggregate with granulated blast furnace slag leads to an increase in the coefficient of constructional quality, that is, the decrease in compressive strength of concrete is compensated by an even more significant decrease in the density of the material, and therefore a decrease in mass. The increase in the coefficient of constructional quality of concrete based on foamed slag, natural crushed stone and granulated blast furnace slag in comparison with the control composition was 14%.


2014 ◽  
Vol 600 ◽  
pp. 227-239
Author(s):  
Hanan A. El Nouhy

This research investigates the influence of high temperature on the properties of bricks containing non-ground granulated blast-furnace slag (GBFS) as fine aggregate replacement. Replacement percentages were 0%, 25% and 50% by dry weight of fine aggregates. The manufactured bricks were exposed to 200°С, 400°С, 600°С, and 800°С for a constant duration of two hours after 28 days of curing. Tests were conducted according to both Egyptian Standard Specifications (ESS) and American Society for Testing and Materials (ASTM) in order to determine compressive strength, absorption percentage, oven-dry weight, and ultrasound pulse velocity. Also, loss in weight was performed. Compressive strength limit regarding load-bearing units was met by mix 1 at all tested temperatures. Mixes 2 and 3, resulted in compressive strength that satisfied the requirement for load-bearing units at temperatures ranging from room temperature to 600°С.Compressive strength obtained regarding mixes 2 and 3 met the requirements of non-load bearing units at 800°С. The control mix resulted in normal weight bricks when tested at the various temperatures till 600°С. At 800°С, mixes 2 and 3 yielded light weight and medium weight bricks, respectively. There was a significant reduction in mass when comparing the mass at 800°С with the corresponding mass at room temperature concerning the three mixes. Results showed that it is feasible to partially replace fine aggregate with GBFS even when bricks are subjected to elevated temperature.


2012 ◽  
Vol 575 ◽  
pp. 100-103 ◽  
Author(s):  
Dong Sheng Shi ◽  
Ping Han ◽  
Zheng Ma ◽  
Jing Bo Wang

In this paper, the experiment about compressive strength of concrete using granulated blast furnace slag as fine aggregate was introduced. In this experiment, granulated blast furnace slag fine aggregates that were produced by two different steel factory and natural river sands that came from two different producing area were been used, and compressive strength of concrete for testing were four levels from ordinary strength level to high strength level. As results, the compressive strength of concrete that used granulated blast furnace slag as fine aggregate increase with increasing of concrete age as good as the concrete used nature river sand. At the early age of 3 days and 7days, whether water-cement ratio, the compressive strength of concrete using slag fine aggregate is always lower than concrete using river sand. At the long age of 91 days, the compressive strength of concrete using slag fine aggregate exceed the concrete using river sand when water-cement ratio was greater than 30%. The compressive strength of concrete using granulated blast furnace slag as fine aggregate can exceed 80N/mm2, the granulated blast furnace slag can be used in high-strength concrete.


2021 ◽  
Vol 2070 (1) ◽  
pp. 012173
Author(s):  
Ganesh Naidu Gopu ◽  
Sri Durga Vara Prasad M ◽  
Swaroop Babu Mylavarpu ◽  
S Ankarao

Abstract Most superior cements delivered today contain materials notwithstanding Portland cement to help accomplish the compressive strength or solidness execution. These materials include fly ash, silica fume and ground-granulated blast furnace slag used discretely or in coalescence. Concurrently, chemical admixtures such as high-range di-hydrogen monoxide-reducers are needed to ascertain that the concrete is facile to convey, place and culminate. For high-strength cements, a blend of mineral and compound admixtures is almost consistently fundamental to guarantee accomplishment of the necessary strength. The Primer investigations have been done on concrete, Fine aggregate and coarse aggregate. The Blend Extent for M200 grade concrete is determined 1: 0.313: 1.463 by following the plan methodology given by ACI Strategy. By keeping up the w/c proportion as 0.25, the multi day Compressive strength, Flexural strength and Split elasticity of cement at 3% of silica fume and 1.5% of conplast have been accomplished as 163.33 N/mm2, 8.4 N/mm2& 9.5 N/mm2 separately. The variety of solidarity of cement with the variety of silica fume is appeared in bar outline. The strength of the concrete might be as yet expanded by decreasing the w/c proportion and expanding the level of silica fume


2017 ◽  
Vol 68 (6) ◽  
pp. 1182-1187
Author(s):  
Ilenuta Severin ◽  
Maria Vlad

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.


This paper aims to investigate the influence of alkaline activators solution i.e, Na2SiO3 / NaOH on compressive strength of geopolymer concrete mixed with Ground Granulated Blast furnace slag (GGBS) for constant molarity 8 M. The ratio of alkali to binder ratio is taken as 0.5 and the ratio of Na2SiO3 / NaOH is 2.5. The geopolymer mix is based on pervious sutdies. As per Indian standard size moulds for the cube, cylinder and prism are cast, cured and tested.The specimens were tested for fresh concrete properties such as slump cone test and hardened properties such as compressive strength for cubes, split tensile strength for cylinders and flexural strength for prism different days of curing under ambient temperature. Also, a microstructural study is done by using Scanning electron microscopy (SEM), Energy dispersive X-ray (EDX) for the tested sample. It is found from the test results that, with the aid of alumino-silicate solution, early strength is achieved by geopolymer concrete within 7 days under ambient condition due to the presence of ground granulated slag.


2015 ◽  
Vol 16 (SE) ◽  
pp. 509-517
Author(s):  
Fatemeh Sayyahi ◽  
Hamid Shirzadi

 In this study, the properties of concrete with different amounts of Ground Granulated Blast-Furnace Slag (GGBFS) has been studied. In another part, the test deals to assess the properties of concrete containing GGBFS with micro-SiO2. The results show that the slag has pozzolan properties and its use up to 20% in the concrete, has no harmful effect on concrete properties. The simultaneous use of micro-SiO2 with blast furnace slag have little effect, as well as micro-SiO2 covers the defects caused by the use of slag. The results indicate that the use of micro-SiO2 and slag has good effects on the strength of concrete up to a certain age, so that its compressive strength is increased. Water-cement ratio was 0.42 and 12.5 mm for maximum size of aggregate and cement content in concrete was 425 kg per cubic meter. Compressive strength of concrete samples was measured at ages 7, 28, 56 and 90-day and flexural and tensile strength and water absorption after 28-day and 90 days also was measured.


Sign in / Sign up

Export Citation Format

Share Document