Building materials, Basic civil engineering ,unit-1

basic civil engineering chapter 1 as per CSVTU,BHILAI SYLLABUS

1. BASIC CIVIL ENGINEERING & MECHANICS ( AS PER SYLLABUS OF CSVTU BHILAI , JAN-JUNE, 2020 ) BUILDING THE FUTURE / RESPONSIBLE FOR BETTER BUILDING / YOU DREAM IT , WE BUILD IT PARIMAL JHA ( H.O.D ) CIVIL ENGG. DEPT. CHATTISGARH ENGINEERING COLLEGE , DURG

2. SYLLABUS & SCHEME COURSE : B.TECH SUBJECT : BASIC CIVIL ENGINEERING & MECHANICS COURSE CODE : A000215(020) TOTAL MARKS IN E.S.E : 100 TOTAL DURATION IN ESE : (3:00 HOURS)

3. COURSE OBJECTIVES( UNIT WISE ) ( UNIT-1 ) BUILDING MATERIALS C.O-TO INTRODUCE ABOUT THE PROPERTIES OF COMMON BUILDING MATERIALS. ( UNIT-2 ) BUILDING CONSTRUCTION C.O-TO INTRODUCE THE BASIC CONCEPTS OF CONCRETE AND FOUNDATION. ( UNIT-3 ) SURVEYING & LEVELLING C.O-TO INTRODUCE THE BASIC CONCEPTS OF SURVEYING AND LEVELLING. ( UNIT-4 ) GENERAL SYSTEM OF FORCES C.O-TO INTRODUCE THE BASIC CONCEPTS OF GENERAL SYSTEM OF FORCES . ( UNIT-5 ) ANALYSIS OF PLANE TRUSS C.O-TO INTRODUCE THE SIMPLE METHODS OF ANALYZING TRUSS .

4. UNIT-1 BUILDING MATERIALS BRICK : A BRICK IS AN ARTIFICIAL RECTANGULAR BLOCK USED FOR BUILDING WALLS,PAVEMENTS AND OTHER MASONRY STRUCTURE. THERE ARE 2 TYPES OF BRICKS: (a) MODULAR (b) TRADITIONAL (a) Modular/Standard Bricks - Modular  bricks conform to the size laid down by Bureau of Indian Standard Institution, India . Any brick which is of the same uniform size as laid down by BIS is known as the modular brick . The actual size of the brick is 19cm x 9cm x9cm . Modular   bricks  are economical to manufacture, require less area for drying, and staking and requires less brick work for the same surface area of the wall in comparison to conventional  bricks . The masonry with modular  bricks  workout to be cheaper. MODULAR BRICK PAVEMENT (road)- pave means cover so pavement means material by which we can cover. A road surface or pavement is the durable surface material laid down on an area intended to sustain vehicular or foot traffic, such as a road or walkway MASONRY -The art and craft of building and fabricating in stone, clay, brick, or concrete block. Construction of poured concrete, reinforced or unreinforced, is often also considered  MASONRY

5. TRADITIONAL BRICK - Traditional bricks are those which have not been standardized in size. The dimensions of traditional bricks may vary from place to place. The length varies from 20 to 25 cm, width varies from 10 to 13 cm, Thickness varies from 5 to 7.5 cm. the commonly adopted nominal size of traditional size of brick is ( 23 cm x 11.4 cm x 7.6 cm ) TRADITIONAL /CONVENTIONAL BRICK (IN INCHES) 1”= 2.54 cm

6. FROG - A Depression of about 10 to 20 mm in depth placed on raw brick during moulding . Purpose : This depression acts as a key for mortar when bricks are laid thus increasing the bond . Provides space for the manufacturer to print his LOGO/Trademark

7. QUALITIES OF GOOD BRICK Bricks should be uniform in color, size and shape. Standard size of brick should be maintained . with sharp and square edges . The brick should have deep red or cherish colour as a measure of uniform chemical composition. They should be free from cracks and other flaws such as air bubbles, stone nodules etc. Bricks should not absorb more than  1 ⁄ 5  of their own weight of water when immersed in water for 24 hours (15% to 20% of dry weight). The compressive strength of bricks should be in range of 2000 to 5000 psi (15 to 35 MPa ). Compressive Strength  of  Bricks ( i )  Compressive Strength  of first class  brick  is 105 kg/cm 2 . ( ii)  Compressive Strength  of 2nd class  brick  is 70 kg/cm 2 . (iii) Compressive Strength  of common building  brick  is 35 kg/cm 2 . Red mud brick Fly ash brick A.A.C block Water Absorption test Crushing strength test

8. Salt attack hampers the durability of brick. The presence of excess soluble salts in brick also causes efflorescence. The percentage of soluble salts (sulphates of calcium, magnesium, sodium and potassium) should not exceed 2.5% in brunt bricks. Brick should not change in volume when wetted. Bricks should neither over burnt nor under-brunt. Generally,  the standard  weight  of a  brick  is 3.2 – 3.5 kg approximately . and the unit weight should be less than 1,100 kg/m3. Bricks should be non-inflammable and incombustible. Bricks should be free from lime pitting . When two bricks struck together metallic sound should be produced The brick should be so hard that when scratched by finger nail no impression is made efflorescence Under burnt bricks Over burnt bricks

9. TESTS ON BRICKS COMPESSIVE STRENGTH WATER ABSORPTION EFFLORESCENCE HARDNESS SOUNDNESS STRUCTURE DIMENSIONAL TOLERENCE

10. Dimension tolerance of bricks

11. WATER ABSORPTION OF BRICKS Dry the specimen in a ventilated oven at a tem­perature of 105 °C to I15°C till it attains sub­stantially constant mass. Cool the specimen to room temperature and obtain its weight ( M 1 ). Immerse completely dried specimen in clean water at a temperature of 27 ± 2°C for 24 hours. Remove the specimen and wipe out any traces of water with a damp cloth and weigh the specimen ( M 2 ) . Complete the weighing 3 minutes after the speci­men has been removed from water Water absorption, percent by mass, after 24-hour immersion in cold water is given by the following formula:

12. COMPRESSIVE STRENGTH OF BRICKS To determine the crushing strength of the brick : Two faces of the brick are made smooth and flat. They are kept under water for 24 hour and then taken out. Excess water is wiped out with cloth. Frog of the brick is finished with cement mortar and kept under damp jute bag for 24 hour. These bricks are allowed to dry for about 2 to 3 days. These bricks are now placed in UTM between the pressure plates and loaded gradually at the rate of 14 N/mm 2 till its failure. Compressive strength UNIVERSAL TESTING MACHINE

13. Ingredients of Portland cement and their functions COMPOSITION Approximate composition of raw materials used for manufacturing ordinary Portland cement

14. TYPES OF CEMENT

15. PORTLAND CEMENT ORDINARY POZZOLANIC ORDINARY PORTLAND CEMENT CLINKER + GYPSUM (3%) POZZOLANE PORTLAND CEMENT CLINKER + GYPSUM (3%) + FLYASH (35%) PORTLAND SLAG CEMENT CLINKER + GYPSUM (3%) + Slag (35%)

16. Grades of Cement. Grade is the 28 days strength when tested as per Indian Standards under standard conditions. If it is 33-grade cement then it has strength equivalent to 33 MPa (330 kg/cm2). Similarly 43 & 53 grades can be defined. Ordinary Portland Cement (OPC) is classified into 3 grades, viz. 33, 43 & 53 grades Composition: OPC is produced by inter-grinding clinker with gypsum (approx. 3 to 4%); BIS permits addition of only up to 1% additive in OPC Grade of Cement Details 33 Grade Ordinary Portland Cement(IS: 269 -1989) The compressive strength after 28 days is 33 N/mm2 Used for general construction works in normal environmental conditions. Cannot be used where higher grade of concrete above M-20 is required. The use of this cement has progressively decreased and virtually phased out. 43 Grade Ordinary Portland Cement (IS: 8112 - 1989) Most widely used cement for general construction work. Minimum 28 days Compressive Strength -43 N/mm2. Used for construction of residential, commercial and industrial buildings, roads, bridges, flyovers, irrigation projects and other general civil construction works. Suitable for all types of applications - RCC, Plastering, Masonry5. Rajashree is the premium OPC 43 brand in the market giving strength of around 65 MPa at 28 days. 53 Grade Ordinary Portland Cement IS: 12269 - 1987 Introduced in 1991 by Grasim - Birla Super. Minimum 28 days Compressive strength - 53 N/mm2 Gives 10-15% saving in cement consumption & 5-8% saving in steel consumption provided higher grades of concrete say M30 and above are used. Useful for high rise buildings bridges, flyovers, chimneys and pre-stressed structures where high grade concrete is required. Gives better durability characteristics to concrete -high grade concrete can be made with lower water cement ratio

17. Fineness Fineness of cement is property of cement that indicate particle size of cement and specific surface area. and indirectly effect heat of hydration. IMPORTANCE/EFFECT OF FINENESS OF CEMENT: Fineness of cement affects hydration rate hence the rate of strength gain. Fineness is a measure of how even each granules are, leading to a greater surface area & greater the surface area more the adhesion . Bleeding can be reduced by increasing fineness.

18. As per IS: 4031 (Part 1) – 1996. The cement of good quality should have less than 10% of wt of cement particles larger than 90 µm. (micron) To determine the number of cement particles larger than 90 µm. or Fineness test of cement. The following apparatus is used.

19. Procedure for finding Fineness test of cement : Take a sample of cement and rub the cement with your hands. The test sample should be free of lumps. Now Take 100g of cement and note it as W1. Pour 100g of cement in 90 µm sieve and close it with the lid. Now place the sieve in Sieve shaking machine for two minutes. You can also shake the sieve with your hands by Agitating the sieve in planetary and linear movements for 15 minutes. Neatly, weight the residue retained on the 90 µm sieve as W2. Then calculate the percentage of Weight of cement-retained on Sieve. Repeat the above experiment with three different samples of cement and average the values for accurate results. A good cement should retain 10% wt of cement when it is sieved with the 90µm sieve.

20. Tests on Cement Consistency Limits Determination of Initial Setting Time Determination of Final Setting Time Needle Plunger This test is performed to estimate the quantity of water to be mixed with cement to form a paste of normal consistency. Take 300 g of cement and add about 25% of water to it and mix properly. Paste is filled into the mould of the Vicat’s apparatus. Time of gauging should be 4± 0.25 minute. Plunger is lowered gently on to the paste in the mould and the settlement of the plunger is noted. If the settlement is between 5 and 7 mm from the bottom of the mould, the amount of water added to the cement is considered to be correct. If this condition is not satisfied, the test is repeated.

21. Tests on Cement Consistency Limits Determination of Initial Setting Time Determination of Final Setting Time Needle Plunger Initial setting time is the time taken during operation as the water is added to the cement and when the paste starts closing its plasticity. Take 300 g of cement and add with % of water as determined in consistency test. Paste is filled into the mould of the Vicat’s apparatus. Square needle of 1 mm X 1 mm cross section is attached to the movable rod of Vicat apparatus so that the needle touches the surface of the paste. In the beginning, the needle will completely pierce the test block Repeat this procedure until the needle, when brought in contact with the test block and released as described above, fails to pierce the block beyond 5.0 ±0.5 mm measured from the bottom of the mould.

22. Tests on Cement Consistency Limits Determination of Initial Setting Time Determination of Final Setting Time Needle Plunger Replace the needle of the Vicat apparatus by the needle with an annular attachment. The cement shall be considered as finally set when, upon applying the needle gently to the surface of the test block, the needle makes an impression thereon, while the attachment fails to do so. The period elapsing between the time when water is added to the cement and the time at which the needle makes an impression on the surface of test block while the attachment fails to do so shall be the final setting time. In the event of a scum forming on the surface of the test block, use the underside of the block for the determination.

23. Compressive Strength of Cement The compressive strength is one of the important properties of cement. Strength tests are not made on neat cement paste because of difficulties in obtaining good specimens and in testing with a consequent large variability of test results. Cement-sand mortar and, in some cases, concrete of prescribed proportions, are used for purpose of determining the strength of cement . Purpose: To find the compressive strength of the cement. Materials : 1- Ordinary Portland cement. 2- Standard sand ( Rounded single size particles passed on sieve 850 µm (No.20) and not more than 10% pass through sieve 600 µm (No.30) ). 3- Water . Apparatus: 1- Compression testing machine with a capacity at least 500 kN and accuracy 1 kN . 2- Steel cube moulds of 70.7 mm internal dimensions. 3- Cube vibrating machine. 4- Balance, 5- Water bath for curing. 6- Container, Hand gloves, Trowel , Scoop, Glass Graduated. Temperature (27 ± 2 o C) , Humidity (65 ± 5 %) Cube vibrating machine STEEL CUBE MOULD ( 70.6*70.6*70.6 mm3) (IS:10080 )

24. HAND GLOVES TROWEL CONTAINER GRADUATED GLASS C.T.M WEIGH BALANCE SCOOP CURING TANK

25. PROCEDURE : 1 Prepare cement-sand mortar, with a mix proportion 1:3 and water to both weights of cement and sand ratio of 10 %. Use 200 grams of cement. 2 Mixing cement and sand at dry condition for one minute then add the water and continue the mixing for 4 minutes. 3 Oiling the internal faces of the mould. 4 Place the mould on the vibrating machine and fill it with a mortar. 5 Operating the vibrating machine for at least 2 minutes or until full compaction has achieved. 6 Level the surface of the mortar and mark on it. 7 Store the moulds in air under temperature about 20 ±1 o C and a minimum relative humidity of 90 %, for 24±0.5 hour. 8 Open the moulds and take out the cubic specimens, then submerge in a water bath of temperature about 20±1 o C up to the date of the test. 9 Testing the specimens at the age of 3, 7 and 28 days by compression testing machine and apply the load with a gradual rate up to the failure. 10 Record the load required for the failure. Compute the compressive strength by dividing the failure load by the sectional area of the cube. 11 Find the average compressive strength of three cubes.

26. Construction Material – cement 200gm ,sand 600 (1:3), Calculation: Compressive strength of cement = ( p/ A ) MPa . Where: P = failure load (N). A = sectional area of the cube (mm2 ) Specification: Iraqi standard specification 5/1984 Age 3 day 7 day Compressive strength of ordinary Portland cement ( MPa ) 15 23

27. Functions of Sand in mortar 1) Sands are mainly used as a inert material to give volume in mortar for economy. 2) It subdivides cementing material into a thin film which is the principle of using all cementing material. 3) It offers requisite surface area for film of cementing material to adhere and spread. 4) Prevents shrinkage and cracking of mortar. 5) Well graded sand provide density. 6) It allows CO 2 to enter in some depth in case fat lime mortar and increase setting power. 7) Some chemical reaction take place between silica of sand grain and other cementing material.

28. Mortar Mix proportions for various uses. Proportion of Cement Mortar The Proportion means the relative quantity of different components to be mixed to make good mortar, or simply the ratio between different materials( cement & sand). Following are the proportions of cement mortar which is commonly recommended for different works: 01. Masonry Construction : For ordinary masonry work with brick/ stone as a structural unit. – 1:3 to 1:6 For reinforced brick work – 1:2 to 1:3. For all work in moist situations – 1:3 For Architectural work – 1:6 For Load Bearing structures – 1:3 or 1:4

29. 02. Plaster Work : For External Plaster and Ceiling Plaster – 1:4 Internal Plaster (If sand is not fine i.e. Fineness Modulus> 3) – 1:5 For Internal Plaster (if fine sand is available) – 1:6 For external plaster work, as per Government of India, ‘CPWD SPECIFICATIONS (VOL.-2)’ (Central Public Works Department), the under coat shall consist of cement mortar 1:5 (1 cement: 5 coarse sand) and the top coat shall be of cement mortar 1:4 (1 cement: 4 fine sand) unless otherwise specified . 03 . Flooring Work : Mortar ratio of 1:4 to 1:8 (cement: sand, water to be judgmental), for 5 to 7 times thickness of verified tiles, should be given as bed between RCC floor and tiles. 04. Pointing Work : For pointing work proportion of cement mortar should be 1:1 to 1:3