Study on Pumice Use in High Performance Lightweight Concrete

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IOP Conference Series:

Earth and

Environmental Science

PAPER • OPEN ACCESS

Study on Effects of Pumice in High Performance Light Weight Concrete by Replacing Coarse Aggregates

To cite this article: V Manoj et al 2021 IOP Conf. Ser.: Earth Environ. Sci. 822 012012

View the article online for updates and enhancements.

Study on Effects of Pumice in High Performance Light Weight Concrete by Replacing Coarse Aggregates

Manoj V¹, Sridhar R², Ajey Kumar V G³

1Department of Civil Engineering, Sri Venkateshwara College of Engineering, Bengaluru, Karnataka, India.

2Department of Civil Engineering, SJB Institute of Technology, Bengaluru, Karnataka, India.

3JRF, Department of Civil Engineering, Sri Venkateshwara College of Engineering, Bengaluru, Karnataka, India.

Email Id: [email protected], [email protected], [email protected]

Abstract. Pumice is a rock particle that was used in this experiment's concrete, and light weight aggregate is a type of aggregate that is lighter than natural aggregate. The major purpose of the suggested methodology is to use optimization techniques to frame a mathematical model. Structural lightweight concrete is used extensively in the construction sector, particularly in high-rise buildings. Only lightweight aggregates can be used to make it. Pumice is a solid component and a highly porous rock light in nature that can be used as an alternative to coarse aggregate (CA) in concrete and Nano Silica an alternative for cement. This lightweight aggregate, on the other hand, has a higher density than other natural and artificial lightweight aggregates. As a result, the density of concrete made with this lightweight aggregate is relatively high, falling into the semi-lightweight concrete category. According to the latest analysis, to further at the density of an lightweight concrete with high strength, Pumice was partially replaced with a coarse aggregate. In this study, pumice was substituted for CA in percentages of 0%, 20% and 30% by quantity and Nano Silica replaced in 1-3% for different mixes to predict three output parameters such as compressive strength (Mpa), split tensile strength (Mpa), flexural strength (Mpa). The addition of pumice to CA concrete decreases density while also lowering all mechanical properties, according to test results. This is because pumice has a smooth surface texture and has a lower density than CA. On the other hand, lightweight concrete containing more than 20% pumice changes into structural lightweight concrete with excellent strength. Several studies demonstrated an overall gain in strength as well as weight loss. As a result, light-weight concrete is equal to heavy-weight concrete in terms of strength.

Keywords: Nano Silica, Pumice Aggregate, Light Weight, High Performance Concrete

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1. Introduction

The weight of concrete is one of the most important factors to consider while creating a cost-effective structure. [1]Because it has a lower self-weight and is more efficient, lightweight concrete is more cost-effective than regular concrete. Lightweight concrete has been used since ancient times and is a fascinating research topic because of its multiple benefits, including reduced transportation costs, reinforcement, and base costs, cost-effective scaffolding and shape function, enhanced constructability, no surface bleed water, sound absorption, and superior anti-condensation properties.

[2] Internal curing improved heat insulation, fire resistance, and frost resistance by increasing hydration, reducing the tendency to buckle due to temperature gradients, lowering seismic pressures, and improving heat insulation, fire resistance, and frost resistance. Furthermore, lightweight aggregate is a widely used lightweight material. Foamed technology or lightweight aggregate can be used to make lightweight concrete[3]. Natural LWAs including diatomite, pumice, volcanic cinders, scoria, and tuff, as well as artificial LWAs such expanded clay, shale, slate, perlite, and vermiculite, were used in construction[4]. Aggregates are vital in bonding the cement paste to obtain good strength, and their gradation and distribution require special attention in order to achieve a densified micro-structure and well-packed concrete, which can minimise cracks in the concrete elements and assess high early strength. To penetrate the interfacial zone between aggregates and cement paste, the aggregate size should be limited to 50 microns to 10 millimetres as a result of the early strength.

2. Experimental Programme

This section of the paper discusses laboratory investigations on concrete mixes prepared with pumice as a partial replacement for natural coarse aggregate in M80 grade concrete.

2.1. Materials Used

Cement: Because of its excellent particle size distribution and superb crystallised shape, 53 Grade OPC produces constructions with great strength and endurance. (5) It has several advantages in applications where specific high-strength concrete is required, such as skyscrapers and bridges, because it is made of high-strength cement. Furthermore, by replacing OPC 53 for lower-grade cement, overall savings can be realised because the amount of cement required is lowered. [6] When 53 Grade OPC is utilised instead of any other grade, an 8-10% discount can be realised. OPC 53 Grade cement must meet BIS criteria IS: 12269-1987 for 28 days strength to be achieved.

Table 1. Tests on Cement

SL NO. TESTS RESULTS

1 Specific Gravity 3.16

2 Normal Consistency 31%

Aggregates: Cement and water consumption can be reduced by using coarse aggregate with the largest permissible maximum size. When coarse aggregates are utilised in excess of the specified size, they might interlock and form arches or obstacles within the concrete form. This results in a vacuum, or at the very least a void filled with finer sand and cement particles, in the area below.

Table 2. Material properties of Coarse Aggregates

2 Water absorption 0.8%

3 Fineness Modulus 7.27

4 Impact Test 7.29%

[7] In the building and construction industry, the term sand refers to fine aggregate, which is defined as material with a particle size of less than 5mm. Coarse sand is characterised as a substance with

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particles smaller than 5mm and finer than 0.15mm in less than 10% of the total. Fine sand is defined as material with a grain size of less than 1.0mm.

Table 3. Properties of Manufactured sand

2 Sieve Analysis Zone II

3 Bulk Density 1880 Kg/m³

Pumice: Pumice rocks and sand fraction were chosen as aggregates for the laboratory work. [8]

Formalized paraphrase Coarse and fine aggregates must be used in all blends. The coarse aggregate is crushed pumice with a size range of 2 to 6 mm. The particle form, surface texture, pores, and grading of pumice aggregates can affect the workability, aggregate/cement ratio, and water requirement of a concrete mix.

Table 4. Tests on Pumice

2 Water absorption 26%

3 Fineness Modulus 7.16

4 Impact Test 38%

Water: For both the preparation and curing of the concrete, potable water conforming to IS: 456 was used.

Chemical Admixture: It's a naphthalene-based new generation hyper plasticizer that's specifically engineered for self-compacting concrete and can minimise water by up to 15-20% at low dosages, making it perfect for the precast concrete industry and high-performance concrete manufacturing.

Fibre: Synthetic macro polypropylene (HPP) fibres in incorporated in to the concrete mix to enhance the tensile strength properties.

2.2. Concrete Mix Proportioning

The mix proportion is prepared for M20 grade concrete according to IS: 10262-2009 and IS 456-2000 guidelines, with a target strength of 26.6 MPa at 28 days. All of the mix proportions use the same amount of cement, water, and fine aggregate. To investigate the effects of recycled plastic waste aggregates in concrete, a total of ten concrete mixtures were made. Table 5 shows the proportions of materials used in the process.

Table 5. Mix proportions

Sl

No % of

Pumice % of Nano

Silica (%) Cement

(Kg/Cub.m) Fine aggregates (Kg/Cub.m)

Coarse aggregates (Kg/Cub.m)

Pumice

(Kg/Cub.m) Nano Silica

(Kg/Cub.m) Water (Kg/Cub.

m) 1

20%

0 522 549 996.8 249.2 0 207

2 1 516.78 549 996.8 249.2 5.22 207

3 2 511.56 549 996.8 249.2 10.44 207

4

30%

0 522 549 880 299 0 207

5 1 516.78 549 880 299 5.22 207

6 2 511.56 549 880 299 10.44 207

3. Results and Discussions 3.1. Fresh Properties of Concrete

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Slump values were measured in freshly prepared concrete mixes to determine their workability. IS:

1199 was used to examine the initial slump of all of the concrete mixes under investigation. Concrete subsistence from the top of the slump cone was used to calculate the slump values. Additionally Vee- bee consistometer and Compaction factor test is conducted to determine fresh properties of concrete.

Table 6. Workability Test Results

Sl. No. Test conducted Result obtained IS code Book

1 Slump cone test 100 mm

IS 1199: 1959

2 Vee-bee test 6 sec.

3 Compaction factor test 0.92

The test results are satisfied with the IS codal provisions in fresh state and no segreagtion or bleeding has been noticed.

3.2. Hardened properties of concrete

At 3,7,14 & 28 days of curing, the compressive strength, flexural, and split tensile strengths were determined according to IS: 516 and IS: 5816.

Table 7. Strength Test Results at 20% replacement of Pumice Nano-silica

content

No. of days Compressive strength test, Mpa

Split tensile strength test, Mpa

Flexure tensile strength test, Mpa

0% 3

7 14 28

25.74 29.48 57.40 82.30

7.50 7.31 6.50 6.21

11.20 10.50 9.80 8.90

1% 3

7 14 28

27.67 35.40 58.56 84.30

7.20 6.94 6.37 5.94

10.50 9.80 9.10 8.65

2% 3

7 14 28

28.89 37.56 60.30 87.36

8.16 7.46 7.05 6.92

13.23 12.80 12.10 11.80

It is noticed that the use of nano silica for 2% in volume of concrete has achieved maximum strength parameters in replacment of pumice to coarse aggregate for 20%.

Table 8. Strength Test Results at 30% replacement of Pumice Nano-silica

content

No. of days

Compressive strength test, Mpa

Split tensile strength test, Mpa

Flexure tensile strength test, Mpa

0% 3

7 14 28

23.65 28.63 55.27 79.85

7.23 6.93 6.28 6.02

10.76 10.36 9.75 8.70

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1% 3

7 14 28

25.23 31.32 58.90 81.50

7.85 7.56 6.75 6.26

10.95 10.50 10.15 9.68

2% 3

7 14 28

28.20 31.30 60.30 85.65

8.68 8.05 7.46 6.78

12.96 12.56 11.95 11.69

By addition of 2% nano silica with 30% replacement of pumice with coarse aggregate has given good results compared to other percentage of nano silica in concrete.

3.2.1 Compressive Strength

In accordance with IS: 516, the compressive strength parameters of cubical concrete specimens measuring 150 mm x 150 mm x 150 mm were calculated in the laboratory. The findings are shown in Figures 1 and 2.

Figure 1. Compressive strength test results 20% replacement of Pumice

Figure 2. Compressive strength test results 30% replacement of Pumice

0 10 20 30 40 50 60 70 80 90

0% nano silica 1% nano silica 2% nano silica

20% PUMICE Replacement

3 days 7 days 14 days 28 days

0 10 20 30 40 50 60 70 80 90

30% PUMICE Replacement

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3.2.2 Flexural Strength Test

All mixes created with conventional and waste recycled plastic aggregates had their flexural strength evaluated using firm concrete specimens with dimensions of 700 X 150 X 150 mm, as stated in IS:

516 figure 3 and 4.

Figure 3. Flexural strength test results 20% replacement of Pumice

Figure 4. Flexural strength test results 30% replacement of Pumice

3.2.3 Split Tensile Strength Test

The splitting tensile strength of all the mixes was tested utilising destructive testing of cylindrical hardened concrete specimens measuring 100 mm dia x 200 mm in accordance with IS 516 after 28 days of moist curing. Figures 5 and 6 show the impacts of various mix combinations.

0 2 4 6 8 10 12 14

20% PUMICE Replacement

0 2 4 6 8 10 12 14

30% PUMICE Replacement

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Figure 5. Tensile strength test results 20% replacement of Pumice

Figure 6. Compressive strength test results 30% replacement of Pumice 4. Conclusion

The compressive strength of more than 80 MPa was achieved by optimizing the volume fraction of alternative materials in this study on replacing pumice for coarse aggregates. The following conclusions were drawn based on the experimental investigations, from the above results, partial replacement of pumice stone with coarse aggregates for 20% & 30% in which 20% replacement has given better compressive strength (87.36MPa) for 2% nano silica replacement for cement content with better workability performance. For 20% replacement of pumice the flexural strength of 11.80MPa and split tensile strength of 6.92MPa has been achieved. Replacing cement with Nano silica up to 2%

provides the best optimal performance in strength parameters and can play vital role in Co2 emission control. The pumice can be said as best alternative materials which reduces the dead weight of high performance light weight concrete.

0 1 2 3 4 5 6 7 8 9

20% PUMICE Replacement

0 1 2 3 4 5 6 7 8 9 10

30% PUMICE Replacement

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5. Future Scope

 The other light weight alternative materials for coarse aggregate replacement can be used and strength parameters to be studied, so further the best light weight aggregate will be determined to produce high performance concrete.

 Other cementitious materials can be used to study the strength parameters to find the best alternative material to replace cement in producing high performance concrete

References

[1] Collins C. Investigation on the properties of lightweight concrete consisting of expanded glass aggregate pulse velocity method [Master Project]. GA, USA: Georgia Southern University; 2019.

[2] ASTM C-1761. (2012). “Standard Specification for Lightweight Aggregate for Internal Curing of Concrete,” Annual Book of ASTM Standards 4(2), West Conshohocken, PA:

ASTM International.

[3] Fengjuan Liu, Jialai Wang*, XinQian, Joseph Hollingsworth,”Internal curing of high performance concrete using cenospheres”, Cement and Concrete Research, Cement and Concrete Research 95, 39–46, (2017).

[4] A. M. Mustafa Al Bakri, G. Che Mohd Ruzaidi, M. N Norazian, H. Kamarudin and S.Mohammad Tarmizi. 2011. Effects of HDPE Plastic Waste Aggregate on the Properties of Concrete. Journal of Asian Scientific Research. 1(7), pp. 340-345.

[5] N.Sivakumar,S. Muthukumar,” Experimental studies on high strength concrete by using recycled coarse aggregate” vol.4,PP 27-36 .

[6] J. O. Ukpata, M. E. Ephraim, and G. A. Akeke, “Compressive strength of concrete using lateritic sand and quarry dust as fine aggregate,” Journal of Engineering and Applied Sciences, vol. 7, no. 1, pp. 81–92, 2012.

[7] P. Ramadoss, “Modeling for the evaluation of strength and toughness of high-performance fibre reinforced concrete,” Journal of Engineering Science and Technology, vol. 7, no. 3, pp.

280–291, 2012.

[8] K. Hossain, S. Ahmed, M. Lachemi, Lightweight concrete incorporating pumice basedblended cement and aggregate: mechanical and durability characteristics Constr. Build.

Mater. 25 (3) (2011) 1186–1195.