Partial Replacement of Cement with Marble Powder free essay sample

PARTIAL REPLACEMENT OF CEMENT WITH MARBLE POWDER A MINI PROJECT REPORT Submitted by; RAHUL-M JAMSHEED . P MUHAMMAD SHANIL . K. P GEO . P. JOSE JAGADEESH . K. A | | | | | | | | In partial fulfilment of the requirements for the award of degree of BACHELOR OF TECHNOLOGY IN CIVIL ENGINEERING DEPARTMENT OF CIVIL ENGINEERING AWH ENGINEERING COLLEGE KUTTIKKATOOR DEPARTMENT OF CIVIL ENGINEERING AWH ENGINEERING COLLEGE CALICUT-8 KERALA 2011 CERTIFICATE This is to certify that this report entitled â€Å"partial replacement of cement with marble powder† is a bonafide record of the mini project presented by rahul , jamsheed, shanil , geo, and jagdeesh, under our guidance towards the partial fulfilment of the requirements for the award of bachelor of technology degree in civil engineering, by the university of Calicut during the year 2011. Guide;Head of department; Miss. DIVYA RAJAN Prof. Dr. M. R. MADHAVAN NAMBIAR LECTURER HOD, civil engineering dept; Department of civil engineering AWH ENGINEERING COLLEGE AWH ENGINEERING COLLEGE ACKNOWLEDGEMENT We take this opportunity to express our sincere gratitude to Prof. We will write a custom essay sample on Partial Replacement of Cement with Marble Powder or any similar topic specifically for you Do Not WasteYour Time HIRE WRITER Only 13.90 / page Dr. M. R. MADHAVAN NAMBIAR (the Head of CIVIL engineering dept;) and Miss. DIVYA RAJAN (Our guide for the project) for their constant encouragement, valuable suggestions and inspiration, which help us to optimize this project. We are thank full to BABU . S (staff in charge of mini project) for his kind co-operation. We also wish to express our deep thanks to Miss, ANUSHA . A (lab assistant, civil department) and all the teachers of civil engineering department for their whole hearted co-operation and moral support. Finally we convey thanks to our friends for installing us the strength and power required to fulfil any work extended to us. ABSTRACT Leaving the waste materials to the environment directly can cause environmental problem. Hence the reuse of waste material has been emphasized. Waste can be used to produce new products or can be used as admixtures so that natural resources are used more efficiently and the environment is protected from waste deposits. Marble stone industry generates both solid waste and stone slurry. Whereas solid waste results from the rejects at the mine sites or at the processing units, stone slurry is a semi liquid substance consisting of particles originating from the sawing and the polishing processes and water used to cool and lubricate the sawing and polishing machines. Stone slurry generated during processing corresponds to around 40% of the final product from stone industry. This is relevant because the stone industry presents an annual output of 68 million tonnes of processed products. These industrial wastes are dumped in the nearby land and the natural fertility of the soil is spoiled. Therefore the scientific and industrial community must commit towards more sustainable practices. There are several reuse and recycling solutions for this industrial by-product, both at an experimental phase and in practical applications. Keeping the above in view, cement is partially refilled with marble powder in concrete. Concrete blocks replaced with 5%, 10%, 15% 20%. Marble powder have been prepared and compared with standard blocks of conventional cement. These blocks are then tested for properties like compressive strength and tensile strength. The results obtained are quite encouraging. Compressive strength is within the average permissible compressive strength as per IS 2185 (Part1) 1979. As per IS 456 2000 the relation between compressive strength and tensile strength of the obtained result is between the permissible limits. It opens the door for further experimentation in the field of roads and high rise buildings. CONTENTS Acknowledgement1 Abstract 2 Content List of figures and tables Chapter -1 Introduction Chapter -2 objectives and scope of investigation (2. 1) objectives (2. 2) scope of investigation Chapter – 3 study Chapter 4 testing on physical properties of material (4. 1) setting time of cement (4. 2) fineness of cement (4. 3) specific gravity (4. 3a)specific gravity of cement (4. 3b) specific gravity of coarse aggregate (4. 3c)specific gravity of fine aggregate (4. 4) sieve analysis (4. 4a)sieve analysis of fine aggregate (4. 4 b) sieve analysis of coarse aggregate Chapter -5 mix design (5. 5) determination of cement content (5. 6) Determination of fine and coarse aggregate content (5. ) Mix proportion Chapter – 6 experimental procedure (6. 1) test for compressive strength of concrete (6. 2) test for tensile strength of concrete Chapter – 7 result and discussion (7. 4) discussion Chapter – 8 comparison with IS code Chapter – 9 conclusion Chapter – 10 reference LIST OF FIGURES AND TABLES; (4. 3. 1) Specific gravit y of coarse aggregate (4. 3. 2) specific gravity of fine aggregate (4. 4. 1) sieve analysis of fine aggregate (4. 4. 2) grading limit of fine aggregate (4. 4. 3) sieve analysis of coarse aggregate (4. 4. 4) particle size distribution curve (5. 1) design stipulation (5. 2) water cement ratio curve (5. ) approximation of sand and water content (5. 6. 1) entrapped air content (5. 6. 2) mix design (6. 1) casted cube and cylinder (7. 1) compressive strength 7 days (7. 2) compressive strength 28 days (7. 1. 1) graphical representation of compressive strength (7. 3. 1) tensile strength 7days (7. 3. 2) tensile strength 28 days (7. 3. 3) graphical representation of tensile strength Chapter 1; INTRODUCTION INFLUENCE OF MARBLE DUST AS PARTIAL REPLACEMENT OF CEMENT IN CONCRETE The advancement of concrete technology can reduce the consumption of natural resources and energy sources and lessen the burden of pollutants on environment. Presently large amounts of marble dust are generated in natural stone processing plants with an important impact on environment and humans. This project describes the feasibility of using the marble sludge dust in concrete production as partial replacement of cement. In INDIA, the marble and granite stone processing is one of the most thriving industry the effects if varying marble dust contents on the physical and mechanical properties of fresh and hardened concrete have been investigated. Slump and air content of fresh concrete and absorption and compressive strength of hardened concrete were also investigated. Test results show that this industrial bi product is capable of improving hardened concrete performance up to 10%, The compressive strength of concrete was measured for 7 , and 28 days. In order to evaluate the effects of marble dust on mechanical behaviour, many different mortar mixes were tested. Chapter 2; OBJECTIVES SCOPE OF INVESTIGATION; (2. 1)OBJECTIVES In this project our main objective is to study the influence of partial replacement of cement with marble powder , and to compare it with the compressive and tensile strength of ordinary M20 concrete. We are also trying to find the percentage of marble powder replaced in concrete that makes the strength of the concrete maximum. Nowadays marble powder has become a pollutant. So , by partially replacing cement with marble powder, we are proposing a method that can be of great use in reducing pollution to a great extent. (2. 2) SCOPE OF INVESTIGATION This study is confined to the utilisation of marble dust in place of cement for making concrete blocks. Properties like compressive strength and tensile strength are only studied and suitably is arrived by comparing it with specifications given in BUREAU OF INDIAN STANDARDS (B. I. S). Chapter – 3; STUDY We have referred various projects using marble powder conducted by different research institutions they are 1) In co- operation of marble sludge in industrial building Eco blocks or cement bricks formulation Producing eco blocks to be used in houses ‘building from marble sludge through maximum possible substitution of sludge for sand and other components of the mixed materials used in blocks manufacturing was investigated successfully. By, FAKHER J AUKOUR – THE HASHEMITE UNIVERSITY OF JORDAN 2) Feasibility study of manufacturing eco blocks concrete using sludge powder as raw material. The feasibility study of manufacturing eco blocks concrete using sludge powder as raw material. By , FAKHER J AUKOUR – THE HASHEMITE UNIVERSITY OF JORDAN Chapter – 4; TESTING ON PHYSICAL PROPERTIES OF MATERIALS GENERAL; Concrete blocks are being widely used nowadays. The performance of concrete depends on the quality and quantity of the ingredients such as cement, aggregates, sand, and water. Without the study of the properties of ingredients of concrete work in depth and range, the study of concrete is incomplete. Experimental investigations have been carried out to evaluate the physical and mechanical characteristics of all the aggregates to be used in the manufacture of concrete blocks. (4. 1) SETTING TIME OF CEMENT Initial setting time is the time elapsed between the moment that the water is added to cement to the time that the paste start losing plasticity. The final setting time is the time elapsed between the moment water is added to the cement, and the time When the paste has completely lost its plasticity and has attained sufficient fineness to resist certain definite pressure. Setting time is tested in vacate apparatus. Take 400 gm of cement paste with . 85P water by weight of cement. Where P is the standard consistency of cement. Start stop watch at a instant when the water is added to the cement. Fill the vicat mould with cement paste and smooth the surface of paste and lower the needle gently in contact surface test block. Repeat the process until the needle starts to pierce the block for about 5mm measure from bottom. That time between water added to cement and the needle falls to 5mm measure. IS SPECIFICATION For Portland Pozzuolana cement initial setting time should less than 30 minute and final setting time is not greater than 600 minute. INITIAL SETTING TIME = 34 minutes (4. 2) FINENESS TEST The fineness of cement has an important bearing on the rate of hydration and hence on the rate of gain of strength and also on the rate of evolution of heat. Fineness of cement offer great surface area and hence faster development of strength. Weigh accurately 100 gm of cement and place it on a IS sieve 90 micron. Break down the air set lump on the sample with fingers. Continuously sieve the sample for 15 minutes . Weigh the residue left on sieve. It is the fineness of cement IS SPECIFICATION Fineness shall not exceed 10% for ordinary cement. FINENESS MODULUS = 6% (4. 3 ) SPECIFIC GRAVITY Specific gravity is defined as the ratio between the weight of the given volume of solid to the weight of equal volume of water. (4. 3a ) SPECIFIC GRAVITY OF CEMENT (LE – CHATLIER FLASK) Specific gravity is defined as the ratio between the weight of the given volume of cement to the weight of equal volume of water. The test is done in LE- CHATLIER FLASK. The flask is filled with kerosene oil to appoint on stem between 0 and 1ml. Put 100 gm of cement in flask and note the rise of kerosene level in the flask. That is the specific gravity of cement. Weight of cement used= 60 gm Initial reading on flask = 0 ml Final reading on flask= 23 ml Specific gravity of cement= weight of cement used Weight of equal volume of water Specific gravity of cement = 2. 608 (4. 3 b) SPECIFIC GRAVITY OF COARSE AGGREGATE;- Specific gravity of coarse aggregate is found out by pyconometer method. Take the empty weight of pycnometerM1 , Add coarse aggregate into it about half of the bottle and note the weight M2. Then add water full above the coarse aggregate and note the weight M3. Empty the pycnometer bottle and fill it with water and weigh, that is M4. Using these observation find out specific gravity of coarse aggregate TABLE(4. 3. 1) SPECIFIC GRAVITY OF COARSE AGGREGATE SL NO | DETERMINATION| Gm| Gm| 1| Pycnometer (M1)| 458| 463| 2| Pycnometer + aggregate(M2)| 706| 666| 3| Pycnometer+ aggregate +water(M3)| 1405| 1385| 4| Pycnometer+ water (M4)| 1258| 1253| CALCULATIONS;- Specific gravity =(M2-M1) (M2-M1)-(M3-M4) (a) (706-458) = 2. 45 (706-458)-(1405-1258) (b) (666-463) = 2. 859 (666-463)-(1385-1253) Mean of these = 2. 66 Therefore, specific gravity of coarse aggregate = 2. 66 (4. 3 c) SPECIFIC GRAVITY OF FINE AGGREGATE;- Specific gravity of fine aggregate is found out by pyconometer method. Take the empty weight of pycnometerM1 , Add sand into it about half of the bottle and note the weight M2. Then add water full above the sand and note the weight M3. Then the pycnometer bottle is cleaned and take full of water and weight it ie M4. Using these observation find out specific gravity of fine aggregate TABLE( 4. 3. 2) SPECIFIC GRAVITY OF FINE AGGREGATE;- SL NO| Determination | Gm| Gm| 1| Pycnometer (M1)| 458. 10| 451| 2| Pycnometer + sand (half of bottle)(M2) | 676| 697| 3| Pycnometer+ sand + full of water (M3)| 1390| 1405| 4| Pycnometer + full of water (M4)| 1253| 1258| CALCULATIONS;- Specific gravity = (M2-M1) (M2-M1)-(M3-M4) a). (676-458. 10) = 2. 693 (676-458. 10)-(1390-1253) b) (697-451) = 2. 49 (697-451)-(1405-1258) Therefore, specific gravity of fine aggregate = 2. 59 (4. 4)SIEVE ANALYSIS;- The sieve analysis is conducted to determine the particle size distribution of sample aggregate which called gradation. The better grade, voids ratio is less and high workability of concrete. (4. 4 a)SIEVE ANALYSIS OF FINE AGGREGATE ;- IS sieve size 4. 75mm, 2. 36 mm, 1. 18mm, 600 micron, 300 micron , 150 micron, and 90 micron were taken, and placed in such a way that large sieve on the top. Take 100 gm of fine aggregate and put it in the top sieve then sieve about 5 minute and collect weight of sample retained in each sieve. From these observation find fineness modulus of fine aggregate. Quantity of sand = 1 Kg Time of sieving = 15 minutes TABLE (4. 4. 1) SIEVE ANALYSIS OF FINE AGGREGATE SL NO| SIEVE SIZE| WEIGHT RETAINED| %OF WEIGHT RETAINED| CUMULATIVE % RETAINED| CUMULATIVE % PASSING| 1| 40mm| 0| 0| 0| 100| 2| 20mm| 0| 0| 0| 100| 3| 10mm| 0| 0| 0| 100| 4| 4. 75| 0| 0| 0| 100| 5| 2. 36| 98| 9. 8| 9. 8| 90. 2| 6| 1. 18| 60| 6| 15. 8| 84. 2| 7| 600micron| 188| 18. 8| 34. 6| 65. 4| 8| 300micron| 397| 39. 7| 74. 3| 25. 7| 9| 150micron| 221| 22. 1| 96. 4| 3. 6| 10| 90micron| 21. 5| 2. 15| 98. 5| 1. 45| 11| L. P| 19. 5| 1. 95| 100| 0| Fineness modulus = 329. 4 100 = 3. 29% TABLE(4. 4. 2) GRADING LIMITS OF FINE AGGREGATE IS 383 1970 | Percentage passing by weight for| | GradingZone1| GradingZone2| Grading zone 3 | Grading zone 4| 10 mm| 100| 100| 100| 100| 4. 75mm| 90-100| 90-100| 90-100| 95-100| 2. 36mm| 60-95| 75-100| 85-100| 95-100| 1. 18mm| 30-70| 55-90| 75-100| 90-100| 600 micron| 15-34| 35-59| 60-79| 80-100| 300 micron| 5-20| 8-30| 12-40| 15-50| 150 micron| 0-10| 0-10| 0-10| 0-15| According to IS383 1970 the given fine aggregate belongs to zone 3 (4. 4. b)SIEVE ANALYSIS COARSE AGGREGATE;- For sieve analysis of coarse aggregate IS sieve NO; 40 mm, 20mm, 10mm, 4. 5mm, are used , and these sieves are arranged in such a way that large sieve is on the top. Take 4000gm of coarse aggregate and placed it on the top of the sieve . and sieved for 10 minutes using mechanical sieve. Then find out weight of retained on each sieve. Using these observation find out fineness modulus of coarse aggregate. Quantity of materials = 4 kg Time of sieving= 10 minutes TA BLE(4. 4. 3) SIEVE ANALYSIS COARSE AGGREGATE;- SL NO| Sieve size| Weight retained(gm)| %weight retained| Cumulative % weight retained| Cumulative %weight passing| 1| 40mm| 0| 0| 0| 100| 2| 20mm| 585. 0| 14. 625| 14. 5| 85. 375| 3| 10mm| 3260| 81. 5| 96. 12| 3. 88| 4| 4. 75mm| 155| 3. 875| 100| 0| 5| 2. 40mm| 0| 0| 100| 0| 6| 1. 18mm| 0| 0| 100| 0| 7| 600m| 0| 0| 100| 0| 8| 300m| 0| 0| 100| 0| 9| 150m| 0| 0| 100| 0| | | | | 710. 77| | Fineness modulus = 710. 77 100 = 7. 10% PARTICLE SIZE DISTRIBUTION CURVE FOR FINE AND COARSE AGGREGATE FIGURE (4. 4) From the graph the grading of fine and coarse aggregate is analysed Chapter 5 MIX DESIGN: Mix design for concrete was made using the properties of constituents of concrete. Grade of concrete was taken as M20 and the mix design was done as per IS:10262-1982 and IS:456-2000. The water cement ratio was taken as 0. 5 which should be the maximum for M20 grade under mild exposure condition . MIX DESIGN OF M 20 TABLE(5. 1) DESIGN STIPULATIONS SL NO| DESIGN STIPULATIONS| QUANTITY| 1| Characteristic compressive strength required in the field at 28 days| 20N/mm2| 2| Maximum size of aggregates| 20mm(angular)| 3| Degree of workability| 0. 90 (compacting factor)| 4| Degree of quality of control | Good | 5| Type of exposure| Mild| TABLE(5. 2) TEST DATA FOR MATERIAL SL NO| TEST DATA FOR MATERIAL| QUANTITY| 1| Cement used| Portland slag cement| 2| Specific gravity of cement| 2. 08| 3| Specific gravity of fine aggregate| 2. 59| 4| Specific gravity of coarse aggregate| 2. 66| 5| Water absorption of fine aggregate| Nil| | Water absorption of coarse aggregate| Nil| 7| Free moisture of fine aggregate| Nil| 8| Free moisture of coarse aggregate| Nil| 9| Sieve analysis of fine aggregate| Grade 3| TARGET MEAN STRENGTH FOR MIX DESIGN fck =fck +1. 65s fck =20+1. 654. 6 = 27. 59N /mm2 As per IS;10262-1982, FIG (5. 2) WATER CEMENT RATIO CURVE From the figure water cement ratio is . 5 TABLE (5. )APPROXIMATE SAND AND WATER CONTENT PER CUBIC METER OF CONCRETE FOR GRADES UPTO M35 Nominal maximumSize of aggregate(mm)| Water content perCubic meter of concrete(kg)| Sand as percent ofTotal aggregate byAbsolute volume| 10| 208| 40| 20| 186| 35| 40| 165| 30| From table 5. 3; Water content = 186 kg/m3 Sand content = 35% For change in value of water cement ratio, compacting factor and sand belonging to Zone 3 ,the following adjustment is required TABLE(5. 4) ADJUSTMENTS IN WATER CONTENT AND SAND CONTENT Therefore, required sand content as percentage of total aggregate by absolute volume = 35 3. 5 = 31. 5 % Required water content =186 + (186x 3) / 100 = 186 + 5. 58 =191. 6 litre /m3. (5. 5)DETERMINATION OF CEMENT CONTENT;- Water cement ratio = 0. 50 Water = 191. 61 Cement = 191. 6/0. 50 = 383 kg/m3 This cement content is adequate for mild exposure condition, according to Appendix A of IS ; 456-1978 . (5. 6)DETERMINATION OF COARSE AND FINE AGGREGATE CONTENT APPROXIMATE AIR CONTENT TABLE (5. 6. 1 )ENTRAPPED AIR NOMINAL MAXIMUM SIZEOF AGGREGATE| ENTRAPPED AIR AS PERCENTAGEOF VOLUME OF CONCRETE| 10| 3. 0| 20| 2. 0| 40| 1. 0| From table 5. 6 for the specified maximum size of 20mm , the amount of entrapped air in the wet concrete is 2%. Taking this into account and applying equations from 3. 5. 1 of IS ; 10262 -1982 Calculation of aggregate contentWith the quantities of water and cement per unit volume of concentric and the ratio of fine to total aggregate already determined, the total aggregate content per unit volume of concrete may be calculated from the following equations;V = [W + C/Sc + 1/ p . a/Sta ] x [1/1000], and V = [W + C/Sc + 1/(1-p) . Ca / Sca ] x [1/1000]Where,V= absolute volume of fresh concrete, which is equal to gross volume (m3) minus the volume of entrapped air. W= mass of water (kg) per m3 of concrete,Sc= specific gravity of cement,P= ratio of fine aggregate to total aggregate by absolute volume,fa ,Ca= total mass of the fine aggregate and coarse aggregate (kg) per m3 of co ncrete respectively, and Sfa , Sca = specific gravities of saturated surface dry fine aggregate and coarse aggregate respectively. Therefore, For fine aggregate ;- 0. 98 = [191. 58 + (383. 16/2. 608)+(1/0. 315) x (f a / 2. 59) ] x (1/1000) f a = 525. 82 For coarse aggregate ;- 0. 98 = [ 191. 58 + (383. 16/2. 608) + (1/(1-0. 315) x (Ca / 2. 83)] x (1/1000) Ca = 1139. 43 kg/m3 The mix proportions then becomes; TABLE (5. 6. 2) MIX DESIGN VOLUMES Volume of cube= 15 x 15 x 15 =3375cm3 Volume of cylinder= ? x 7. 52 x 30 =5301. 44cm3 Total volume= 8676. 44cm3 Add 10% extra volume = 9544. 084 Volume of concrete = (1 / 2. 602) + (1. 372 / 2. 59) + (2. 97 / 2. 6) + (0. 5 / 1) = 2. 529 Weight of cement = (1 / V) x volume = (1 / 2. 529) x 9544. 084) = 3. 77kg Weight of fine aggregate = 1. 372 x 3773. 85 = 5. 177 kg Weight of coarse aggregate = 2. 97 x 3773. 85 = 11. 208 kg Required amount of water = 0. 5 x 3773. 85 = 1886. 92 litre FOR TWO SPECIMEN Weight of cement = 7. 547 kg Weight of fine a ggregate = 10. 355 kg Weight of coarse aggregate= 22. 41 kg Required water= 3-77 litre (5. 7)MIX PROPORTIONS: Five concrete mixes with stone dust were produced, replacing 0%(reference mixture ), 5%,10%,15%,and 20%,Cement, in terms of weight. The concrete mix proportion for M20 grade was designed in accordance with I. S. code. QUANTITY OF MARBLE POWDER; 5% of cement replaced by marble powder = 377. 38gm 10% of marble powder = 754. 7 gm 15% of marble powder = 1. 13 kg 20 %of marble powder = 1. 5094 kg Chapter – 6; Experimental procedure: Compressive strength of concrete was undertaken on 15 x15x15cm specimens. at 7 days and 28 days of age. Regarding splitting tensile strength, cylinders with 30 cm of height and 15 cm of diameter were casted and tested at 28 days of age. All specimens were removed 48 hours after casting, and then transferred to regular conditions (interior of the laboratory ) till testing. (6. 1) TEST FOR COMPRESSIVE STRENGTH OF CONCRETE PROCEDURE 1. Cast the cube of size 150*150*150mm3 and specimen from the mould is placed in water tank at a temperature of 27+2 degree Celsius till the date of test. 2. Place the concrete cube on the testing machine in between the 2 plunger of the compressive testing machine. . Apply uniform continuous load at that rate of 14N/mm2. 4. Increase the load until the specimen splitter records maximum load required to split the cube. 5. Remove the load and take off the broken cube between the plunger. (6. 2) TEST FOR TENSILE STRENGTH OF CONCRETE PROCEDURE 1. Cast the cylinder of size150*300mm2 from the mix and cure for 28 days. 2. Test the specimen immediately after removing f rom water. 3. Diameter and length of the specimen shall be cantered along the centre of the plate. 4. Place the specimen on plywood strip aligned at the centre. 5. Place the second plywood strip length wise at the top of the cylinder. 6. Apply the load without shock and increase the load continuously at the rate of 1. 4 N/mm2 2. 1N/mm2. Figure (6. 1) CASTED CUBE AND CYLINDER Chapter – 7 RESULTS AND DISCUSSIONS; COMPRESSIVE STRENGTH Table (7. 1. 1)COMPRESSIVE STRENGTH 7 DAYS | 1| 2| Average| Compressive strength ( MPa)| 0%| 380| 340| 360| 16| 5%| 355| 405| 380| 16. 88| 10%| 390| 430| 410| 18. 22| 15%| 275| 325| 300| 13. 33| 20%| 290| 270| 280| 12. 44| Table (7. 1. 2)COMPRESSIVE STRENGTH 28 DAYS %| 1| 2| average| Compressive strength(MPa)| %| 535| 565| 550| 24. 40| 5%| 580| 620| 600| 26. 67| 10 %| 675| 645| 660| 29. 33| 15%| 470| 435| 452. 5| 20. 11| 20%| 420| 440| 420| 18. 67| Figure (7. 1. 1) GRAPHICAL REPRESENTATION OF COMPRESSIVE STRENGTH; From this graph compressive strength of concrete increases up to 10% replacement of cement with marble powder. There after compressive strength decreases. (7. 3)TENSILE STRENGTH; Table (7. 3. 1)TE NSILE STRENGTH7 DAYS % marble powder| Specimen 1 tensile load| Specimen 2 tensile load| Mean| Tensile strength (MPa)| 0%| 111| 129| 120| 1. 69| %| 130| 136| 133| 1. 88| 10%| 125| 151| 138| 1. 95| 15%| 100| 128| 114| 1. 61| 20%| 108| 84| 96| 1. 35| Table (7. 3. 2)TENSILE STRENGTH28 DAYS % marble powder | Specimen 1, tensile load| Specimen 2, tensile load| Mean| Tensile strength (MPa)| 0%| 170| 178| 174| 2. 461| 5%| 182| 185| 183. 5| 2. 59| 10%| 197| 201| 199| 2. 84| 15%| 165| 170| 167. 5| 2. 36| 20%| 141| 162| 151. 5| 2. 14| Figure (7. 3. 3)GRAPHICAL REPRESENTATION OF TENSILE STRENGTH; From the graph tensile strength of concrete increases up to 10% replacement of cement with marble powder. There after tensile strength decreases. (7. 4) DISCUSSION: Compression Test: Mechanical behaviour of concrete cubes prepared without chemical admixtures was studied by compressive tests (Grade M20and curing time of 7 days and 28 days. It can be noticed that 5% replacement of cement with marble dust in mild condition and 10% replacement of cement with marble dust in mild condition, are showing increase in compressive strength. Tensile Strength test; Mechanical behaviour of cylindrical specimens prepared without chemical admixtures was studied by tensile strength test. Grade M20),curing times of 7 days and 28 days and the results obtained are reported. It is noticed that 5% replacement of cement with marble dust in mild condition and 10% replacement of cement with marble dust in severe conditions, are showing increase in tensile strength. Chapter – 8; COMPARISON WITH IS CODE Table (8. 1)Physical requirements as per IS 2185 ( part 1) – 1979 TYPE| GRADE| DENSITY OF BLOCK(Kg / m3)| MINIMUM AVERAGE COMPRESSIVE STRENGTH OF UNITS (N / mm2)| MINIMUM STRENGTH OF INDIVIDUAL UNITS(N / mm2)| HOLLOW (OPEN AND CLOSED CAVITY) LOAD BEARING UNITS| A(3. )| NOT LESS THAN 1500| 3. 5| 2. 8| | A(4. 5)| | 4. 5| 3. 6| | A(5. 5)| | 5. 5| 4. 4| | A(1. 0)| | 7. 0| 5. 6| | B(2. 0)| LESS THAN 1500 BUT NOT LESS THAN 1000| 2. 0| 1. 6| | B(3. 0)| | 3. 0| 2. 4| | B(5. 0)| | 5. 0| 1. 0| HOLLOW (OPEN AND CLOSED CAVITY) NON LOAD BEARING UNITS| C(1. 5)| LESS THAN 1500 BUT NOT LESS THAN 1000| 1. 5| 1. 2| SOLID LOAD BEARING UNIT| D(5. 0)| NOT LESS THAN 1800| 5. 0| 4. 0| | D(4. 0)| | 4. 0| 3. 2| The average compressive strength obtained in this test is greater than the average compressive strength as per IS 2185 (part 1) – 1979. Hence the partial replacement of cement with marble powder is very effective in solid load bearing unit. Chapter 9 CONCLUSIONS: From our experiment it is proved that marble dust is very effective in assuring very good cohesiveness of mortar and concrete. it is concluded that the marble dust can be used as a replacement material for cement ; and 10% replacement of marble dust gives an excellent result in strength aspect and quality aspect and it is better than the conventional concrete. The results showed that the substitution of 10% of the cement content by marble stone dust induced higher compressive strength, higher splitting tensile strength, and improvement of properties related to durability. Test results show that this industrial waste is capable of improving hardened concrete performance up to 10%, enhancing fresh concrete behaviour and can be used in plain concrete. Chapter 10 REFERENCES: BOOKS 1) M. S. SHETTY – CONCRETE TECHNOLOGY 2) N. KRISHNA RAJU DESIGN OF CONCRETE MIXES IS CODES 1) IS 456 2000 2) IS 456 1978 3) IS 2185 (PART1) 1979 SITES 1) http://www. engineeringcivil. com 2) http://www. elsevier. com