 Open Access
 Total Downloads : 7858
 Authors : Mukesh Dattaram Ghadge, Vaibhav Dhondiram Kamble
 Paper ID : IJERTV4IS080338
 Volume & Issue : Volume 04, Issue 08 (August 2015)
 DOI : http://dx.doi.org/10.17577/IJERTV4IS080338
 Published (First Online): 13082015
 ISSN (Online) : 22780181
 Publisher Name : IJERT
 License: This work is licensed under a Creative Commons Attribution 4.0 International License
Floating Concrete by using Light Weight Aggregates and Air Entraining Agent
Mukesh D. Ghadge Vaibhav D. Kamble
Civil Engineering Dept Civil Engineering Dept
Gharda Institute of Technology,lavel Gharda Institute of Technology,Lavel Maharashtra, India Maharashtra,India
Abstract This Project deals with the development of Floating type of concrete by using lightweight aggregate (Pumice stone) and Aluminium powder as an air entraining agent. There are many types of lightweight concrete which can be produced either by using lightweight aggregate or by using an air entraining agent. In this study we have worked on combination of above mentioned types. This concrete is a nonstructural concrete. In this study, comparison has be made between plain cement concrete and lightweight concrete having different proportion of Aggregate size and fix quantity of Aluminum content (i.e. 2%) by the weight of cement has been taken into account. It helps to increase volume of concrete and hence reduce the weight.
Keywords: Floating concrete, Pumice stone, Aluminium powder
,Fly ash, Density, Compressive strength.
I.INTRODUCTION
The present day world is witnessing construction of very challenging and difficult civil engineering structures. Researchers all over the world are attempting to develop low density or lightweight concrete by using different admixtures in concrete up to certain proportions. This study deals with the development of Floating concrete by using lightweight aggregate (Pumice stone) and Aluminum powder as an air entraining agent. Floating concrete is made by introducing air or gas into concrete slurry, so that when the mix sets and hardens, uniform cellular structure is formed. Thus it is a mixture of water, cement and finely crushed sand. We mix fine powder of Aluminum to the slurry and it reacts with the calcium hydroxide present in it thus producing hydrogen gas. This hydrogen gas when contained in the slurry mix gives the cellular structure and thus makes the concrete lighter than the conventional concrete. Pumice stone is a lightweight aggregate of low specific gravity. It is a highly porous material with a high water absorption percentage. In this we do not use the conventional aggregate and replace it by the pumice stone.Pumice is the specimen of highly Porous rocks having density approximately 500600 Kg/m3. Pumice is produced when superheated, highly pressurized rock is violently ejected from volcano. The unusual foamy configuration of pumice happens because of simultaneous rapid cooling & rapid depressurization. Pumice has an average porosity of 6080% and initially floats on water.

MATERIALS USED
Cement Portland Pozzolona cement Aggregate Pumice Stones 10 to 20 mm Sand – Standard
Other pumice powder Admixtures Aluminium Powder Water Tap water
Mixed Procedure Mixer mixing Compaction Table Vibration
Curing practice – Moist curing by pounding
Cube size 15cmÃ—15cmÃ—15cm
Testing of cubes Compressive test after 28 days.

EXPERIMENTAL PROGRAM TESTING OF MATERIALS
Cement
Standard Consistency Test
Result of Standard Consistency Test is the percentage by weight with respect to cement to produce standard consistency is 34%
Fineness Test Data:
Weight of cement taken (A) =100 gm.
Weight of cement retained on 90Âµ I.S. Sieve (B) = 05 gm. Calculation:
Fineness = (B/A) Ã— 100
= 05%
I.S. requirement for fineness = less than 10% Fineness = 05%
Fineness value is less than 10%. Hence it could be be used in our study.
Setting Time
Weight of cement = 300 gm.
Water content = 0.85 P. Where P = Standard Consistency
= 0.85 Ã— 34%
= 28.9% of cement
= (28.9Ã·100) Ã—300 gm.
= 86.7 gm.
= 86.7 ml
Initial Setting time:
I.S. requirement = more than 30 minutes (as per I.S 4031 1968)
Initial setting time = 40 minutes Final Setting time:
When the test block has attend such hardness that the needle does not pierce through the block more than 0.5 mm, that time is known as final setting time.
I.S. requirement = less than 600 minutes (as per I.S. 4031 1968)
Final setting time = 262 minutes Aluminium Powder:
The test is carried out for checking of how many percentage of volume of concrete is increased by using aluminium powder. We have casted one specimen of size 15 cmÃ—15cmÃ—10cm. It has been observed that after 24 hours height of specimen increased by 2.5 cm.
Therefore increased in volume = (15 Ã—15Ã—12.5) (15
Ã—15Ã—10)= 562.50 cm3
% Volume increased = (562.50Ã· 2250) Ã—100 = 25.0 %
Tests on a light weight aggregates by using pumice stone as a light weight aggregate:
For this study, we got pumice stone as big as 50 mm size. So we crushed it to the size of 20 mm & less. The mix design for the first sample is decided based on the studies, and then further samples were made by changing some proportions in previous ones.
Sample1: 3 cubes
Cement: 19.15 kg
Crushed sand: 24.32 kg
Pumice stone (< 20 mm): 9 kg Water: 10.53 kg
Admixture: Aluminum powder 2%
RESULTS: After 28 days of cube testing
Sp.
No.
Wt. (kg)
Densit
y (kg/m3)
Avg
Density (kg/m3)
Load (KN)
Strength (N/mm2)
Avg.
compSt rength(
N/mm2)
1
5.86
1736
287
12.76
2
5.80
1719
1724.66
267
11.86
11.60
3
5.80
1719
246
10.19
Sample 2: 3 cubes
Cement: 9 kg
Pumice powder: 1.8 kg Crushed sand: 3 kg
Pumice stone: M1 (10 to 20 mm): 9.6 kg
M2 (4.75 to 10 mm): 2.4 kg
Water: 5.4 kg
Admixture: Aluminum powder 2%
RESULTS: After 28 days of cube testing
Sp.No.
Wt. (kg)
Density (kg/m3)
Avg Density (kg/m3)
Load (KN)
Strength (N/mm2)
Avg. Strength (N/mm2)
1
4.84
1434
262
11.64
2
4.90
1452
1438
284
9.20
10.29
3
4.82
1428
228
10.13
Sample 3: 3 cubes
Cement: 7.5 kg Pumice powder: 3.5 kg Crushed sand: 3 kg
Pumice stone: M1 (10 to 20 mm): 7.5 kg
M2 (4.75 to 10 mm): 3 kg
Water: 6.2 kg.
Admixture: Aluminum powder 2%
RESULTS: After 28 days of cube testing
Sp.
No.
Wt. (kg)
Density (kg/m3)
Avg Density (kg/m3)
Load (KN)
Strength (N/mm2
)
Avg. comp Strength
(N/mm2)
1
4.14
1227
167
7.42
2
4.26
1262
1232.6
6
197
8.76
8.15
3
4.08
1209
186
8.27
Sample 4: 3 cubes
Cement: 6 kg Pumice powder: 3 kg
Pumice stone: M1 (10 to 20 mm): 6 kg
M2 (4.75 to 10 mm): 4 kg
Water: 5.8 kg.
Admixture: Aluminium powder 2%
RESULTS: 28 days cube testing
Sp.No.
Wt. (kg)
Density (kg/m3)
Avg Density (kg/m3)
Load (KN)
Strength (N/mm2)
Avg. comp
Strength
(N/mm2)
1
3.82
1132
111
4.93
2
3.94
1167
1141.66
155
6.89
5.52
3
3.80
1126
107
4.76
Sample 5: 3 cubes
Cement: 6 kg Pumice powder: 3 kg
Pumice stone: M1 (10 to 20 mm): 6 kg
M2 (4.75 to 10 mm): 4 kg
Water: 5.8 kg.
Admixture: Aluminum powder 2%
Sp.
No.
Wt. (kg)
Density (kg/m3)
Avg Density (kg/m3)
Load (KN)
Strength (N/mm2)
Avg. Strength
(N/mm2)
1
4
895
65
2.89
2
2.98
883
902.66
68
3.02
3.21
3
3.14
930
84
3.73
RESULTS: 28 days cube testing
Sample 6: 3 cubes
Cement: 6 kg Pumice powder: 3 kg
Pumice stone: M1 (10 to 20 mm): 6 kg
Pumice stone: M1 (10 to 20 mm): 6 kg
M2 (4.75 to 10 mm): 4 kg
Water: 5.8 kg.
Admixture: Aluminum powder 2%
RESULTS: 28 days cube testing
Sp.N
o.
Wt. (kg)
Density (kg/m3)
Avg Density (kg/m3)
Load (KN)
Strength (N/mm2)
Avg. Strength
(N/mm2)
1
3.84
1137
202
8.97
2
3.65
1081
1102.66
196
8.71
8.61
3
3.68
1090
184
8.17

RESULTS AND DISCUSSION
sample1 gives average compressive strength 11.60 N/mm2, which is good for lightweight concrete. Also it gives average density 1724.66 kg/m3, but we have to reduce the density of concrete to nearly equals to density of water, so it is to be required that reduce the quantity of crush sand and thats why we reduced the quantity of crushed sand and also replaced it with pumice sand passing through IS sieve of size 4.75 mm. in next sample. Also we used two fractions of Aggregate i.e. M1 (10mm to 20 mm) and M2 (4.75 mm to 10 mm).
sample 2 gives the improved results having average density 1438 kg/m3 and average compressive strength 10.29 N/mm2, but average density of concrete is not nearly equals to the density of water. Also the quantity of cement is high, so we discussed this situation with our guide. He told us that if you reduce the quantity of cement it will help us to reduce the density as well as to achieve economy. Therefore in next sample we reduced the cement quantity and increased the pumice sand.
sample 3 gives the improved results having average density 1232.66 kg/m3 and average compressive strength 8.15 N/mm2. We reduced the quantity of cement in this sample, but average density of concrete is still not nearly equals to the density of water. Therefore in next sample we again reduced the cement quantity and increased the pumice sand. Sample 4 gives lightweight concrete having average compressive strength 5.52 N/mm2and average density 1141.66 kg/m3, which is nearly equal to the density of water hence the concrete may be float on the water. It was light as
desired but its finishing was not good. It happens because of the large sized aggregate. So we have decided to eliminate large size aggregate completely from concrete & also replace 30% cement by fly ash to achieve economy.
Sample 5 gives lightweight concrete having average compressive strength 3.21 N/mm2and average density
902.66 kg/m3. Which is less than the density of water hence the concrete cube floating on the water. Figure 3 shows the cube floating on water. It was light as desired but its finishing was not good. It happens because of the large sized aggregate. So we have decided to eliminate large size aggregate completely from concrete & also replace 30% cement by fly ash to achieve economy.
Fig.1: Cube showing rough surface
Sample 6 gives lightweight concrete having surface flat & smooth and showing a good finish. Its average density 1102.66 kg/m3 and average compressive strength 8.61 N/mm2. From the above results it seems that the compressive strength is increased even if the density is nearly same as the previous sample. So this sample is perfect for the mix proportion.
Fig.2: Cube showing smooth surface
Density
600
400
200
0
Density
2000
1800
1600
1400
1200
1000
800
Fig.3: Cube floating on water
Compressive Strength
14
12
10
8
6
4
2
0
Graph 1: Average Compressive Strength of Different
Samples
Graph 2: Average density of Different Samples

CONCLUSION
In this study, the influences of aggregate types and the amount on the compressive strength of concrete were investigated. Using different aggregate proportions (pumice) and five different lightweight concrete mixtures were produced with a satisfied strength. The result of the investigation showed that aggregate size and proportion influenced the unit weight and compressive strength of concrete. Moreover, the result showed that it is possible to produce a Floating and satisfied strength concrete by using pumice as aggregate. It was also seen that, using light weight aggregate in the concrete mixture can reduce the dead load but decreases the concrete strength. However for the sample 6 it is Reverse, because this proportion gives compressive strength 8.61 N/mm2, which is good for the light weight concrete having density 1102.66 kg/m3. From cost analysis it is proved that the cost of our project is less than that of brick masonry. The study showed that using pumice aggregate as a commixture enable to produce different strength grade lightweight concrete with different unit weight. These concrete does not satisfies the strength requirements for load bearing structural elements. In this study only strength and unit weight were considered, other properties including carbonation and drying shrinkage, thermal conductivity and sound insulation properties can be investigated as a further study.

REFERENCES

Dhawal Desai, Development of Light Weight Concrete, Civil Engineering Portal, 2014.

T. Parhizkar, M. Najimi and A.R. Pourkhorshidi, (Application of pumice aggregate in structural lightweight concrete, Asian journal of civil engineering (building and housing) VOL. 13, NO. 1 (2012) PAGES 4354.

N. Sivalinga Rao, Y.Radha Ratna Kumari, V. Bhaskar Desai, B.L.P. Swami, Fibre Reinforced Light Weight Aggregate (Natural PumiceStone) Concrete,International Journal of Scientific & Engineering Research Volume 4, Issue 5, May2013 ISSN 2229 5518.

Lakshm Kumar Minapu1, M K M V Ratnam2, Dr. U Rangaraju, (Experimental Study on Light Weight AggregateConcrete with Pumice Stone, Silica Fume and Fly Ash as a Partial Replacement of Coarse Aggregate), International Journal of Innovative Research in Science, Engineering and Technology Vol. 3, Issue 12.

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