ENGINEERING UTILIZATION OF MARBLE SLURRY

Transcription

1 INTERNATIONAL International Journal of Civil JOURNAL Engineering OF and Technology CIVIL ENGINEERING (IJCIET), ISSN 0976 AND 6308 (Print), ISSN (Online) TECHNOLOGY Volume 3, Issue 2, (IJCIET) July- December (2012), IAEME ISSN (Print) ISSN (Online) Volume 3, Issue 2, July- December (2012), pp IAEME: Journal Impact Factor (2011): (Calculated by GISI) IJCIET I A E M E ENGINEERING UTILIZATION OF MARBLE SLURRY Ishwar Chand Sharma 1, Prof.Naresh Chandra Saxena 2 Asso.Prof. &Head 1, Professor 2 in Department of Civil Engineering Arya College of Engineering and Research Centre kookas jaipur Rajasthan India ishwarbng@yahoo.co.in 1 ncs16140@gmail.com 2 ABSTRACT Marble slurry is a processing and polishing waste of marble mining industry. Its huge quantity of the order of 20% out of mined resources is dumped on any empty land, agricultural fields, pasture lands, river beds and road sides. The present dumping practices have been creating a number of nuisances and problems including environmental and human health. Scientific disposal systems but with more emphasis on engineering utilization have to be developed simultaneously and as fast as possible. Construction industries can be the main user of marble slurry whether in bulk or minor quantities. The utilization of marble slurry in mortar either by substitution or addition,in damp proof course(dpc)replacing sand by 50% marble slurry as leak proof material, formwork removing agent, curing and white washing mixture were investigated by field experiments and observations. Formwork removal was easily obtained with smooth surfaces. Using slurry in curing proved to be more efficient, cheap and more beneficial to the concreting process having hardening and gaining strength more than normal. White washing with slurry and lime was proved to be the best option. Keywords: Utilization, Marble slurry, Marble dust, Technical use 1. INTRODUCTION There are several possible applications of marble dust in construction industry. However, probably due to lack of systematic studies, enough data are still not available for its wide spread use in construction. The research on the use of marble dust in concrete needs to be supplemented with durability studies such as permeation properties of near surface 1

2 concrete, carbonation resistance, freeze thermal resistance and corrosion of reinforcement. Self compacting concrete requires fillers for keeping the concrete mix in cohesive state. Therefore, there is a need to investigate use of marble/stone dust as fillers in production of self compacting concrete and its effect on durability. Use of marble/stone dust in road works and bridge approaches could be more scientifically investigated as it has a potential for its huge/bulk consumption. Recent researches conducted in Portugal Almeida et al (1) concluded that there is technical viability to incorporate massive quantities of marble slurry as raw material in the production of clinker without any previous complex treatment. Use of marble slurry for soil stabilization has been undertaken at MNIT (2), Jaipur to improve the properties of soils by addition of marble dust. Improvement in engineering properties indicated that it has a potential for use in road works and bridge approaches. 2. THREE SCALES OF UTILIZATION 1. Small e.g. in mortar, concrete (ii) piecemeal/medium e.g. white washing on walls & (iii) bulk or large quantity e.g. (a) Road construction/bridge (b) cement production (mixed/ground with clinker as raw material) (c) filler in SCC (self compacting concrete) (d) soil stabilization. Marble slurry can be used as admixture (addition) and substitution (replacement partially or wholly). In bulk, bagged storage like cereals / wheat in the godowns of Food Corporation would be much better than silo type construction. Since, it is still a waste; the consideration of bag storage would gain only after its utility is confirmed by research and experiments. 3. ENVIRONMENTAL CONCERN Among solutions to deal with pollutants can be their utilization, scientific or otherwise. Rajasthan State pollution control board (3) had officially ordered: 1.To ensure utilization of marble slurry as premix for manufacture of cement, it is directed that while issuing consent to establish and consent to operate under Air & water acts to the major cement manufacturing units, a consent condition will be imposed making it compulsory to replace at least 1% of the raw material (lime stone) with marble slurry. Cement units which already hold valid consent to establish/operate, a similar consent condition will be added through a corrigendum. 2. Marble processing units will make available marble slurry to the nearest cement units free of cost. Suitable consent condition should be imposed while granting consent to all such units. Marble processing units which already hold valid consent to establish/operate, a similar consent condition will be added through a corrigendum. 2

3 This order binds the cement manufacturing units, major or minor, to replace 1% lime stone by marble slurry at the manufacturing stage 4. MORTAR Marble slurry has been very effectively used in mortar either by substitution or by addition or both. Technically mortar is a mixture of binding agent, for example, cement/lime, fine aggregate and water. The classification of mortar, particularly with reference to slurry research is : cement mortar, lime mortar, lime cement mortar ( also called composite mortar or gauged mortar) and special mortars. In DPC (damp proof course) 1:1:6 (cement+lime+sand) is a very good material and sand replacement by 50% marble slurry had added to the property of damp proofing while saving 50% sand which is a natural resource. Tests on mortars including marble slurry were done for crushing strength. Testing done on cubes of 3 side, was found to increase with 50% marble slurry replacing sand. The increase, however, depended on different w/c ratio ranging from 0.3 to 0.5.Adhesiveness was not found to increase neither it decreased as compared to control, setting tested with Vicat s apparatus was around 30 minutes (initial) and 9 hours (final). Marble slurry (80%) in mortar gave thermal insulating properties reducing temperature up to 6 to 7 0 C. The thickness of plaster was kept around 2 mm. on plastered wall surface. Marble slurry had increased the hardness of plaster coating of thickness 2 mm again by around 10%. The final hardness after due curing was obtained between 4 and 5 MhO. 5. REMOVAL OF FORMWORK Wooden formwork for beams, columns, slabs and other structures require typical actions to be removed from fully cured concrete. Burnt oil is painted between the concrete and formwork on both horizontal and vertical surfaces and yet hammering is done for removal leaving the surfaces rough. A building for academic use was chosen for experiments during construction. For beams and slabs, vertical surfaces of wooden formwork were painted with wet marble slurry before placing concrete. Similarly horizontal surfaces were spread with wet slurry around 2 mm thick and concreting done. Regular curing continued for a required period. After a maximum curing time of 7 days, formwork was removed. It was found that not much effort was required and hammering was certainly minimum. The surface of concrete obtained was not rough but quite smooth and ready for painting without plastering. Marble slurry has the property of not sticking which helps easy removal of formwork 3

4 6 CURING AID A concrete surface 3m X 5m, recently laid and mechanically compacted by vibrator was under experimentation. For curing by ponding method, the boundaries were made by clay so that water could be retained. Before pouring on surface, slurry was mixed with water such that around 30mm thick slurry could be deposited on wet concrete. For such activity around 0.5 slurry was used in 2 water. The mixture of slurry and water itself had retarded evaporation much more than ordinary water without slurry. After almost one day, slurry had started settling and the settlement had completed after two days. Therefore, it was noted that for around 8 days slurry had still been wet for curing to continue. Moisture was held for a long time and evaporation prevented for the required period of curing. Marble slurry, therefore, could be seen as a good curing agent. 7. WASHABLE WALL SKIN The use of marble slurry with lime for white washing purposes was experimented. Six prime vertical surfaces, 1m X 2m each were selected for white washing. Materials used were 100% lime (0% slurry) as control, mixtures of, 20% slurry + 80% lime, 30% slurry +70% lime, 40% slurry+ 60% lime, 50-50% slurry & lime, & 100% slurry (as control). These materials were painted on 6 prime surfaces including three replications of each. Durability of these white washed surfaces was observed for one year and the results tabulated. Blue chemical was added as whitener. Table (1): Effect of marble slurry on durability % marble slurry mixture Durability in Remarks months 0 % slurry + 100% lime 12 No fading but quite white 20 % slurry + 80% lime 6 Slight fading + less white 30 % slurry + 70% lime 7 Fading + white 40 % slurry + 60% lime 10 Not much fading + white 50 % slurry + 50% lime 12 No fading + quite white 100 % slurry + 0% lime halfmonth Completely removed & original surface recovered Without lime, slurry did not white wash and failed. As the % of slurry increased, durability increased, slurry and lime was as good as 100% lime and was quite white and long lasting. 4

5 8. COMPARISION OF CONSTRUCTION MATERIAL Different properties of clay, sand and marble slurry of the local areas were compared in table 2. Some of them were from inspection and the others inferred from experimental experiences. The utilization of slurry requires the properties of these materials so that a mixture in proper proportions gives optimum results. Table (2) Comparison of clay, sand and marble slurry S.NO. Properties Clay Sand Marble slurry 1. Particle size 0.002mm not < o.075 mm Partially visible by visible by naked eye visible by naked eye naked eye 2. Texture Fine Coarse Fine 3. Uniformity Less uniform Uniform Uniform 4. Void ratio High Low High 5. Permeability Low High Low 6. Shrinkage upon drying Very high Negligible High 7. Compression when the load is applied to the surfaces Slowly on the application of load Immediately Slowly on the application of load 8. Cohesion Marked Negligible Marked 9. Swelling Considerable No considerable 10. Elasticity High Low Medium 11. Specific surface Large Small Medium 12. Capillary Very high Not High appreciable 13. Particle shape Scaly Angular Scaly 14. Surface tension Immense surface Low Surface tension tension forces forces exist 15. Size of pores Very minute Large Minute 16. Expansion Most Practically More none 17. Compressibility Very compressible Slight Compressible 18. Volume of voids High (98%) Small (50%) Medium (70%) 19. Capillary pressure Great Low Medium 9. CONCLUSIONS 1. Marble slurry is wholly insoluble in water. It takes time to settle i.e24 hrs 2. Engineering utilization rather than dumping is the best policy to deal with marble slurry. 5

6 3. For DPC (damp proof course) 1:1:6 (cement +lime+sand) where 50 %sand is replaced by marble slurry gives the best constructions material. 4. Using marble slurry in removal of form work for beams, column and slab is easy and efficient and renders smooth surfaces. 5. Marble slurry is a good curing aid because it avoids quick evaporation of water and hydration of cement continues for a required period. 6. For white washing, slurry and lime have proved the desired quality with durability. REFERENCES 1. Almeida, N, Branco, F. &Santo, J.R. (2007, Recycling of stone slurry in industrial activities: Application to concrete mixture. Building and environment, 42(2007) pp Portugal (IST) 2. MNIT (Jaipur) Research communication on use of marble slurry for soil stabilization. 3. Rajasthan State Pollution Control Board, Jaipur (2010) office order by the member secretary, p14 (27) policy/rpce/pig/ dated 4 th March Personal discussion with authorities concerned with marble slurry. 5. Inspection of slurry dumping grounds 6. Consultation with marble processing gangsaw units in Rajasthan. 6