Strength and Durability Studies on Concrete Containing Granite Cutting Waste as Partial Replacement of Sand

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1 Use of Granite Waste in Concrete and Building Products (Hollow Blocks, Bricks, Paver Blocks) Prof. Ravindra Nagar Malaviya National Institute of Technology Jaipur Strength and Durability Studies on Concrete Containing Granite Cutting Waste as Partial Replacement of Sand Graphical representation of Granite Production (in thousand tons). source: DMG Report Granite Granite Granite reserves in Rajasthan are estimated at 8479 million cubic metres and are spread over in the districts of Barmer, Jalore, Pali, Sirohi, Alwar, Jaip ur, Jhunjhunu, Tonk, Ajmer, Bhilwara, S ikar and Udaipur. Prominent cluster of granite processing and quarrying in Rajasthan is Jalore with hundreds of single/ multiblade cutters and tiling plants. The quarries in Jalore, Barmer and Jaisalmer produce a wide variety of stones of excellent quality and colours. 1

2 INTRODUCTION Rajasthan, the largest state in India in terms of area also holds the largest share in the Indian stone industry. It holds vast reserves of various stones like marble, sandstone, granite, limestone and kota stone that fuel the state s economy. The huge stone industry of Rajasthan comprising of mining and processing both accounts for at least thirty percent income of the state and is a bread provider for about a third of population residing here. 4 Granite reserves in Rajasthan are estimated at 8479 million cubic metres and are spread over in the districts of Barmer, Jalore, Pali, Sirohi, Alwar, Jaipur, Jhunjhunu, Tonk, Ajmer, Bhilwara, Sikar and Udaipur. Prominent cluster of granite processing and quarrying in Rajasthan is Jalore with hundreds of single/ multiblade cutters and tiling plants. The quarries in Jalore, Barmer and Jaisalmer produce a wide variety of stones of excellent quality and colours. In the last few years though, this industry has suffered a major setback due to repeated restrictions on mining in certain areas and the growing amount of waste without any suitable place for its disposal. As per Petition No.2150/2004 in Rajasthan High Court, it is violation of the provision of water prevention and control of pollution act

3 5 Stone industry generates a lot of waste both at the mining and the processing stage. The table below indicates a general scenario. Waste generation in stone industry (Source: DMG (Raj.) Report, 2011) 3

4 Dimensional stones production figures for Rajasthan during are as follows Stone Type Granite Limestone (Dim.) Marble & Serpentine Slate & Quartzite Sandstone Total Source: DMG, Rajasthan (Production in Thousand tones) Granite waste dumped on vacant plots near Jalore 8 SOURCE The Hindu Oct

5 स लर स बढ रह स कट 9 Source Rajasthan Patrika feb 2013, jalore Rajasthan stays sand mining till Nov SOURCE The Hindu Nov

6 Objectives Physical and Chemical characterization of Granite Powder. To study Strength and durability properties of concrete mixes containing granite powder. To study change in micro structure, porosity of concrete mixes with addition of granite powder. To study suitability of concrete paver blocks, bricks prepared using granite powder. SEM Micrographs and EDS El C norm. C Compound [wt.%] [wt.%] O Si SiO Al 6.19 Al2O K 4.20 K2O 6.76 Na 2.34 Na2O 4.21 Mg 0.37 MgO Total: (a) Granite El C norm. C Compound [wt.%] O Si SiO Al 5.64 Al2O K 2.72 K2O 3.28 Mg 0.80 MgO Total: (b) Sand 6

7 % passing Physical Properties Particle Size Distribution Material Specific Gravity Granite Sand % Passing sand % Passing granite Material Water Absorption Granite 4.36 Sand 2.9 Sieve Size Scope of Study This study will help in obtaining an optimum replacement percentage of sand by Granite slurry dust. The use of waste stone slurry powder in concrete opens new avenues to further study in the area of alternative uses for granite waste. On one hand the extensive use of waste granite slurry dust in concrete will reduce the cost of concrete as use of sand would come down 7

8 List of test and Specimen size 15 S.No Test Size of specimen No. of specimens 1 Compressive strength 15 cm x 15 cm x 15 cm 9 (Nine) 2 Flexural strength 50 cm x 10 cm x 10 cm 9 (Nine) 3 Abrasion Test 10 cm x 10 cm x 10 cm 3 (Three) 4 Carbonation 10 cm x 10 cm x 10 cm 3 (Three) 5 Sorptivity Test 10 cm x 10 cm x 10 cm 3 (Three) 6 Permeability DIN 15 cm x 15 cm x 15 cm 3 (Three) 7 Chloride Diffusion 15 cm x 15 cm x 15 cm 1 (One) 8 Sulphate Attack 10 cm x 10 cm x 10 cm 3 (Three) 9 Shrinkage 30 cm x 7.5 cm x 7.5 cm 3 (Three) 11 Corrosion Mould Size 1 (One) 12 Pull off Used Beam 13 Acid Attack 10 cm x 10 cm x 10 cm 3 (Three) Casting Beams 8

9 Casting Cubes Slump 9

10 COMPREESIVE Strength 7 Days Strength 28 Days Strength FLEXURE Strength 7 Days Strength 28 Days Strength 10

11 Permeability Abrasion Resistance 11

12 Water Absorption Carbonation 12

13 SEM (0.4 w/c) 0% GCW 40% GCW 70% GCW XRD 13

14 XRD XRD 14

15 Corrosion Rate (mm/year) Macrocell current (µa) Half Cell Potential (mv) Corrosion (0.4 w/c) Exposure Period (months) Macrocell Current v/s Exposure period 0% GCW 10% GCW 25% GCW 40% GCW 55% GCW 70% GCW Exposure Period (Months) % GCW 10% GCW 25% GCW 40% GCW 55% GCW 70% GCW. Half cell Potential v/s Exposure period Corosion Rate of steel bars w/c Ratio 0.35 w/c Ratio 0.30 w/c Ratio GCW (%) Broken corrosion specimen for visual examination 15

16 Weight loss in % age Loss in Compressive Strength (% age) Acid Attack (0.4 w/c) % GCW % GCW 25% GCW 40% GCW 55% GCW days 56 days 84 days 4 70% GCW Immersion Period in days GCW (%) Weight loss Strength loss C0nclusion The key finding of the investigation is that for the type of GCW utilized in the study 25-40% river sand can be substituted with a favourable influence on strength and durability parameters of concrete. The following points can be concluded from the present study: Incorporation of GCW in concrete results in slight loss of workability, which can be effectively mitigated by use of new generation superplasticizers. Substitution of 25% river sand by GCW results in increased compressive strength at 0.30 w/c. Nevertheless upto 40% GCW can be incorporated in concrete as a partial replacement of sand with improved strength at 0.35 and 0.40 w/c over the control concrete. Inclusion of GCW in concrete does not affect the flexural strength of concrete (at 70%) replacement level. The replacement of 40% river sand by GCW results in enhanced flexural strength. Inclusion of 40% GCW in concrete led to comparable or better abrasive resistance than control. When 55% river sand is replaced by GCW in concrete, water permeation and water absorption of concrete reduces. Use of 25% GCW in concrete did not affected the carbonation resistance at 0.30 w/c. Similarly, carbonation resistance of concrete enhanced or remained unaffected by the use of 40% GCW in concrete at 0.35 and 0.40 w/c. Use of 25% GCW at 0.30 w/c and 40% GCW at 0.35 and 0.40 w/c reduced the micro-cracking at interfaces between aggregate and mortar paste. Similarly, hydration mechanism of concrete in aforesaid range remained unaffected. The use of GCW upto 25-40% as partial replacement for natural sand led to similar or better resistance to corrosion as compared to the control concrete. The corrosion rate was observed to be higher at higher w/c. 16

17 Conclusion The minimum weight loss for the GCW substituted concrete specimens on exposure to 3% H 2 SO 4 solution was observed at optimum percentage GCW replacement of 25%. For both the w/c ratios suggesting the potential of such concrete to behave optimally in an acidic environment % GCW can be used as partial replacement of river sand in concrete depending upon the type of construction and w/c involved. The use of GCW as a building material will invarialbely lead to the conservation of river beds. Its use in concrete will contribute to sustainable development & cleaner construction by significantly eliminating the landfills & heaps of such waste from stone processing industrial areas. GCW SUBSTITUTED HOLLOW CONCRETE BLOCKS AS AN INNOVATIVE TURNKEY SOLUTION FOR SUSTAINABLE CONSTRUCTION 17

18 Conclusion 1. The compressive strength and flexural strength results showed that granite slurry can be can successfully replace crushed rock fines (CRF) in the production of concrete hollow blocks. The study was confined to replacement up to 30%, but gradual increase in strength results indicates that further replacement may also be successful. 2.The water absorption of blocks with granite fines increased but it was within the permissible limits and the results indicated that further increase in granite fines may lead to crossing that limit. 3. Thermal conductivity results saw a sharp increase in values as the percentage of granite fines was increased. Although blocks with less thermal conductivity are beneficial for buildings but the values these blocks with granite fines were also within limits. 4. The ultrasonic pulse velocity test results showed that the blocks with more percentage of granite fines have better quality. 5. The block density of concrete hollow blocks with granite fines was decreased. This indicated that the blocks became lighter in weights which have great applications in earthquake resisting structures. 6. The use of waste granite slurry in place of crushed rock fines considerably decreased cost of production concrete hollow blocks. This is economical as well as eco-friendly to environment. 18

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20 Publications Feasibility as a Potential Substitute for Natural Sand: A Comparative study between Granite Cutting Waste and Marble Slurry. 5th ISWMAW IISC Banglore (Excellent Paper Award) Utilization of granite cutting waste in concrete as partial replacement of sand, UKIERI Concrete Congress Sustainable Utilization of Granite Cutting Waste in High Strength Concrete (SCI), Journal of Cleaner Production (Elsevier Journal) Performance of Sustainable Concrete Containing Granite Cutting Waste (SCI), Journal of Cleaner Production (Elsevier Journal) Pull off Strength Test 20

21 Shrinkage 21

22 Carbonation Water Absorption 22

23 Permeability Corrosion 23

24 Sulphate Attack Acid Attack Thanks 24