DOI : 10.17577/IJERTV3IS071383
- Open Access
- Total Downloads : 795
- Authors : Rajath U Pole, M R Suresh
- Paper ID : IJERTV3IS071383
- Volume & Issue : Volume 03, Issue 07 (July 2014)
- Published (First Online): 01-08-2014
- ISSN (Online) : 2278-0181
- Publisher Name : IJERT
- License:
This work is licensed under a Creative Commons Attribution 4.0 International License
Development of Self Compacting Concrete by Replacing Foundry Sand and Granular Blast Furnace Slag for Sand
Rajath U Pole
PG-STUDENT
Civil engineering Dept
Dr. Ambedkarinstitute of technology Bangalore, India
M R Suresh Associate professor
Civil engineering Dept
Dr. Ambedkar institute of technology Bangalore, India
AbstractThe overuse of river sand for construction has various undesirable social and ecological consequences. As a solution for this, various alternatives such as foundry dust, wastes from demolished concrete, industrial wastes like copper slag,foundry sand, eco sand etc have been used. GBFS (Granulated Blast Furnace Slag) is a slag obtained from the manufacture of iron in steel industries. This research aims to investigate the possibility of replacing Granulated Blast Furnace Slag (GBFS) as a sand substitute in concrete.In this investigation, natural sand was replaced by GBFS and foundry sand in various percentages), with a constant water/cement ratio. Tests such as sieve analysis, specific gravity, fineness modulus, and water absorption were done for fine aggregate and GBFS sample. Different mix proportions for different percentage replacement of fine aggregate was obtained for M40 grade concrete as per IS 10262:2009. The compressive strength test, split tensile strength test, flexural strength test, were done for cube, cylinder and slab specimens of control mix and GBFS mix. It was found the strength of concrete was improved due to the addition of GBFS as fine aggregate. Different mix proportions for different percentage replacement of fine aggregate was obtained for M40 grade concrete as per IS 10262:2009. The compressive strength test, split tensile strength test, flexural strength test, were done for cube, cylinder and prism specimens of control mix and GBFS mix. It was found the strength of concrete was improved due to the addition of GBFS as fine aggregate.
Keywordsindustrial waste, river sand, granular blast furnace slag, foundry sand, self compacting concrete, workability, strength, environment.
I.INTRODUCTION
Due to the recent growth in the construction industry, demand for fine aggregate is escalating rapidly. River sand has been the most widely used fine aggregate in India and over exploitation of river sand to meet the demand has led to various harmful consequences such as increase in the depth of the river bed, lowering of the water table,and salinity intrusion into the rivers. Because of these environmental problems, there is a necessity to restrict river sand mining especially at vulnerable locations. As a remedial measure, the government imposes various restrictions on the extraction of river sand with consequent increases in prices.Excessive instream sand mining is a threat to bridges, river banks and nearby
structures. Sand mining also affects the adjoining groundwater system and the uses that local people make of the river.Rising concerns to the alarming situation, of negative environmental impact, has seen strict measures making their way in the southern states of Tamilnadu, Kerala and Karnataka. After banning mining of river sand and other minor minerals without the mandatory environment clearance, the National Green Tribunal (NGT) has recently also banned beach sand mining from the sea coasts of Tamil Nadu and Kerala. Yet, news about illegal sand mining keeps making it's way to the national and regional dailies every now and then. The figures reported to have accounted for loss of minerals through such practices have run into multi-million tones.
Quarrying is thus seen in an unfavorable light because of the environmental impact it has. This is mainly due to de- fragmented operations.
The noticeable effects on environment and the eco system caused by sand mining, together with the growing demand of aggregates to fulfill the construction requirements of the urban world has made it imperative to look for alternate solutions to the concern.
Instream sand mining results in the destruction of aquatic and riparian habitat through large changes in the channel morphology. Impacts include bed degradation, bed coarsening, lowered water tables near the streambed, and channel instability. The development of specifying a concrete according to its performance and requirements, rather than the constituents and ingredients have opened innumerable opportunities for producers of concrete and users to design concrete to suit their specific requirements. One of the most outstanding advances in the concrete technology in the last decade is self-compacting concrete (SCC). SCC consolidates itself due to its self-weight and is de-aerated almost completely while filling the formwork. As defined earlier, no additional inner or outer vibration is necessary for the compaction. In structural members even with high percentage of reinforcement, it fills all voids and gaps completely. SCC flows like honey and has nearly a horizontal concrete level after placing. With regard to its composition, self-compacting concrete consists of the same components as conventionally vibrated normal concrete,
which are cement, aggregates, water additives, water admixture and admixtures. While crushing the rock, extracting sand from private lands and mining for sand in submerged areas are being considered as alternative activities to using river sand, experts claim that Granulated Blast Furnace Slag' is the best option among all. Granulated Blast Furnace Slag is produced from the slag that forms during the production of steel. An American Foundry Society (AFS) study in Illinois investigated foundry sand as a substitute for fine aggregate in concrete. When foundry sands without fines replaced a portion of the fine aggregate, the concrete produced had compressive strengths, tensile strengths and modulus of elasticity values comparable to mixtures composed of natural sand.
-
MATERIALS AND THEIR PROPERTIES
-
Cement
In this experimental study, Ordinary Portland Cement 53 grade, conforming to IS: 8112-1989 to be used. The different laboratory tests are to be conducted on cement to determine the physical and mechanical properties of the cement used.
-
Fly Ash
Fly ash is defined as The finely divided residue that results from the combustion of powdered coal and that is transported by flue gases from the combustion zone to the practical removal system. Fly ash particles are typically spherical, finer than Portland cement and line, ranging in diameter from less than 1 to 150µm
C.Foundry Sand
The raw materials used for making sand molds for metal castings are usually recycled. After a repeated use they lose their characteristics, thereby becoming unsuitable for further use in the manufacturing process. All these materials are then discarded as a waste. They are mainly molding sand and core sand.
-
Granular slag [GBS]
Granular slag from the local steel making plant; Blast Furnace Slag is a byproduct of the steel industry. It is defined as the non-metallic product consisting essentially of calcium silicates and other bases that is developed in a molten condition simultaneously with iron in a blast furnace.
-
Coarse Aggregates
Coarse aggregate to be used is 12mm maximum nominal size. The coarse aggregates confirmed to BIS specifications.
-
Admixtures
A carboxylic-ether polymer based super plasticizer GLENIUM B233 to be used.
-
-
METHODOLOGY
The properties of Self Compacting Concrete is studied where in the river sand is completely replaced in percentages of Foundry and and GBS. The sand replacement materials was introduced in step of 20 percent (0, 20, 40, 60, 80 and 100) proportionally with foundry sand and GBS.SCC mix design of
M40 Grade was carried out by trial and error with reference to European Guidelines. The mix proportion for M40, Cement: Fine aggregate: Coarse aggregate: Fly ashwas 1: 2.18: 1.79:
0.25 with water cement ratio of 0.38. The effect of varying percentages of foundry sand and GBS is subjected to evaluation of fresh properties of SCC namely Slump flow value and V funnel time for filling ability, J ring readings and U box Readings for passing ability and L box readings for segregation resistance, The effects on Hardened Concrete for compressive, split tensile and flexure strength are also determined. Casting and testing of specimens are carried out as perIS codes. IS: 516-1959 for compressive strength for cube of size (150mmx150mmx150mm)& split tensile strength for cylinder of size (150mmx300mm), flexural strength for slab of size (500mmx500mmx75mm). Materials are weigh batched, mixed in a rotating drum mixer, casted.The specimens were stored in room temperature for 24 hours, then removed from the moulds, and cured in normal water until tested.
Figure 1- Compressive test of cube specimen
Figure 2- Split tensile test of cylinder specimen
35 33
U Box H2-H1(mm)
28
30 25 24
25 20
20 17
15
10
5
0
15
H2-H1 mm
Figure 3- Flexural strength test of Slab specimen
L Box H2/H1
1.2
CS R1 R2 R3 R4 R5 R6
Specimen
Figure 5- U Box test results
1.1
-
RESULTS AND DISCUSSION
The results of tests on fresh concrete and hardened concrete are obtained based on experimental study. Identification of specimens is as shown in table 2.
Specimen name
River Sand in %
GBS in %
Foundry Sand in %
CS
100
–
–
R1
–
100
0
R2
–
80
20
R3
–
60
40
R4
–
40
60
R5
–
20
80
R6
–
0
100
Table 1Identification of specimen
1
0.8
0.6
0.4
0.2
0
0.9
0.85 0.8 0.8 0.78
0.73
H2/H1
-
Observation on workability tests
The workability tests are conducted on fresh concrete and the results are shown in table 3 and represented through fig 4 to 8.
Specimen
Slump
U Box H2-H1
mm
L Box H2/H1
V
funnel
Sec
J ring
mm
mm
sec
CS
700
3.00
17
0.90
10.00
5
R1
660
3.00
33
1.10
13.00
10
R2
645
3.50
28
0.85
12.00
11
R3
600
4.00
25
0.80
12.50
11.5
R4
590
4.00
24
0.80
12.50
12
R5
565
4.50
20
0.78
12.80
12
R6
540
5.00
15
0.73
13.00
13
Table 2Workability test results
CS R1 R2 R3 R4 R5 R6
Specimen
Seconds
6
4
2
0
CS R1 R2 R3 R4 R5 R6
Specimen
13 12 12.5 12.5 12.8 13
10
14
12
10
8
VFunnel(seconds)
Figure 6- L box test results
Figure 7- V funnel test results
10
11
11.5
12 12
13
5
Slump Value (mm)
800
600
700 660 645
600 590 565 540
mm
J Ring(mm)
400
200
0
CS R1 R2 R3 R4 R5 R6
Specimen
14
12
10
8
6
4
2
0
mm
CS R1 R2 R3 R4 R5 R6
Specimen
Figure 8- J ring test results
Figure 4- Slump flow
From fig 4 to fig 8, it is observed thatin the fresh state of SCC, the concrete is not as workable as in river sand. However, the workability requirement is mostly satisfied with full replacement of GBS and gets tougher to get workability with the addition of foundry sand.
-
Observation on compressive strengthtest
The cube specimens are subjected to compressive test as shown in fig 1. Table
4 shows the results of compressive test at 7 and 28 days. Fig 9 and 10 represents the bar and line graph of compressive strength for different specimens.
41.22 40.89
50
Compressive Strength in
N/mm2
Table 3Compressive strength test results
Specimen name
Compressive strength
@ 7 Days in N/mm2
Compressive strength
@ 28 Days in N/mm2
CS
28.77
41.22
R1
28.64
40.89
R2
26.34
37.68
R3
23.79
34.03
R4
21.44
30.75
R5
20.14
29.74
R6
18.67
27.61
20
10
0
27.61
18.67
34.03 30.75 29.74
23.79 21.44 20.14
28.77 28.64 26.34
30
40
37.68
41.22 40.89
50
CS R1 R2 R3 R4 R5 R6
Specimen
7 Days 28 Days
20
10
0
18.67
30.75 29.74 27.61
23.79 21.44 20.14
28.77 28.64 26.34
30
37.68
34.03
40
Compressive Strength in
N/mm2
Figure 9- Bar chart representing compressive strength
CS R1 R2 R3 R4 R5 R6
Specimen
7 Days 28 Days
Figure 10- Line chart representing compressive strength
From Table 3, Fig 9 and 10. It can be noticed that concrete acquires almost same compressive strength at 100% GBS as
sand replacement. The percentage of variation in strength with respect to control specimen is -0.80 percent which is negligible.
-
Observation on split tensilestrength test
The cylinder specimens are subjected to split tensile test as shown in fig 2. Table 5 shows the results of split tensile strength test at 7 and 28 days. Fig 11 and 12 represents the bar and line graph of split tensile strength for different specimens.
It can be noticed that concrete acquires almost sametensile strength of SCC with Sand replacement.Compared to SCC having River sand, the variation of strength is -3%.
2.34
2.43
3
2.5
2
1.5
1
0.5
0
Tensile Strength in N/mm2
Table 4Tensile strength test results
Specimen name
Tensile strength @ 7 Days in N/mm2
Tensile strength @ 28 Days in N/mm2
CS
1.48
2.43
R1
1.41
2.34
R2
1.29
2.15
R3
1.22
2.05
R4
1.24
2.09
R5
1.15
1.92
R6
1.13
1.84
1.13
1.15
1.22 1.24
1.29
1.41
1.48
2
1.5
1
0.5
0
1.84
1.92
2.09
2.05
2.15
2.34
2.43
3
2.5
CS R1 R2 R3 R4 R5 R6
Specimen
7 Days 28 Days
1.13
1.15
1.24
1.22
1.29
1.41
1.48
1.84
1.92
2.09
2.05
2.15
Tensile Strength in N/mm2
Figure 11- Bar chart representing tensile strength
CS R1 R2 R3 R4 R5 R6
Specimen
7 Days 28 Days
Figure 12- Line chart representing tensile strength
-
Observation on Flexural Test
The flexure test is performed in the universal testing machine by applying single point load at the central distance
of effective length of slab specimen as shown in fig 3.Minimum reinforcement is provided. 6mm bars with yield strength of 250N/mm2 are provided at a spacing of 150m c/c.The load is applied at equal increments of 2.5KN till the ultimate load carrying capacity.
Table 5Flexural strength test results
60
40
35
30
tle 25
Ti 20
Axis 15
10
5
0
0 2 4 6 8 10
Axis Title Deflection mm
50
Load (KN)
40
30
20
10
0
0 2 4 6 8
Deflection mm Deflection mm
Specimen
Percentage of fine aggregate
Maximum deformation
in mm
Ultimate load in KN
CS
River sand 100
6.4
56.40
R1
GBS100
Foundry Sand 0
6.9
58.86
R2
GBS 75
Foundry dust 25
5.5
49.05
R3
GBS 50
Foundry dust 50
6.56
51.50
R4
GBS 25
Foundry dust 75
8.3
46.60
R5
GBS 0
Foundry dust 100
9.1
36.78
Figure 16- Load deflection curve of Specimen R3
60
50
Load (KN)
40
30
20
10
0
0 2 4 6 8
Deflection mm Deflection mm
50
Load (KN)
40
30
20
10
0
0 2 4 6 8 10
Deflection mm Deflection mm
Figure 17- Load deflection curve of specimen R4
Figure 13- Load Deflection curve of Control Slab
70
60
tle 50
Ti 40
30
Axis 20
10
0
0 2 4 6 8
Axis Title
70
60 40
Load (KN)
50 35
Load(KN)
40 30
30 25
20 20
10 15
0 10
0 2 4 6 8 5
Deflection mm Deflection mm 0
Figure 14- Load deflection curve of Specimen R1
0 2 4 6 8 10
Deflection mm Deflection mm
60
50
Load (KN)
40
30
20
10
0
0 2 4 6
Deflection mm Deflection mm
Figure 18- Load deflection curve of specimen R5
The slab specimens with replacement of river sand showed higher deflections compared to control specimen. The Slab specimen with 100 percent of GBS showed similar deflection and highest ultimate load carrying capacity as of river
Figure 15- Load deflection curve of Specimen R2
sand.The ultimate load carrying capacity of Slab is increased by 4.36 percent in comparison with control Slab.
highest ultimate load carrying capacity.The ultimate load carrying capacity of Slab is increased by 4.36 percent in comparison with control Slab.
70 56.4 58.86
60
Load (KN)
50
40
30
20
10
0
51.5
7) With GBS alone, it is difficult to obtain proper compaction due to voids. Thus foundry sand upto strength requirement can be utilised. GBS upto 80 percent can also be used along with river sand to get optimum results thus saving ecology and also being economical.
49.05 49.6
36.78
50
45
40
CB R1 R2 R3 R4 K4
Specimen
Figure 19- Comparison of ultimate loads
-
-
CONCLUSIONS
In the present study following conclusions are derived
-
Granular Slag &Foundry dust can be a very good replacement for river sand with respect to economy, strength and the considerations of availability of resources. The combination of Foundry dust and Granular Slag in place of River sand & along with fly ash shall be very economical and can also help in the utility of Industrial wastes and in maintaining the ecological balance thus reducing the consumption of cement and river sand.
-
The fresh state of SCC, with the presence of 100% GBS, it caused lower flow ability, passing ability and resistance to segregation of SCC mix. These workability properties gradually decreased with additional percentages of foundry sand. The concrete mixes can still meet the requirement of flow ability, resistance to segregation and passing ability of SCC .
.
-
By experimental investigations it is indicated that the strength parameters such as compressive strength, split tensile strength and flexure strength is similar when compared to the normal SCC.
-
Concrete acquires similar strength in compressive strength at 100% GBS as sand replacement. There is a percentage decrease in strength with additon of foundry sand but economical to use.
-
Split tensile strength have similar strength with Sand replacement compared to SCC having River sand. There was 3 percent decrease in strength compared to river sand
-
The Slab specimens with replacement of river sand showed higher deflections compared to control specimen.The specimen with 100 percent of GBS higher deflection and
35
Load(KN)
30
25
20
15
10
5
0
0 2 4 6 8
Deflection(mm)
REFERENCES
-
Properties of Concrete, by Neville. A. M. Longman, Pearson Education Asia pvt Ltd, Fourth Edition, and First Indian reprint 2000.
-
Design of Concrete Mixes, by N. Krishna Raju, CBS Publishers & Distributors, Delhi, 1993
-
EFNARC Specification and guidelines for self-compacting concrete, European Federation of Producers and Applicators of Specialist Products for Structures, May 2005
-
Okamura Hajime and Ouchi Masahiro. Self Compacting Concrete. Journal of advanced concrete technology, 2003, Vol.1, No.1, pp. 5 15.
-
Japan iron and steel federation, The slag sector in the steel industry
July 2006
-
Mineral Commodity Summaries 1993. Bureau of Mines, U.S. Department of the Interior, Washington, DC, 1993.
-
ASTM, Standard Specification for Ground Granulated Blast-Furnace Slag for Use in Concrete and Mortars, ASTM C 989-99, American Society for Testing and Materials.
-
Concrete Technology theory and practice, by M S Shetty, S. Chand Company Ltd, Delhi, First multi-colour illustrative revised edition, reprint 2008.
-
Naik, T.R. (1987). "Foundry Industry By-Products Utilization." Center for By-Products Utilization, UW-Milwaukee