Mr.Farasat Mehamood Abasi
Transcription
Mr.Farasat Mehamood Abasi
DEPLETION OF NATURAL ROCK & PROCESSING OF AGGREGATES PRESENTED BY : FRASAT MEHAMOOD ABBASI AGGREGATES ARE INERT MATERIALS WHICH ARE MIXED WITH BINDING MATERIALS SUCH AS CEMENT OR LIME FOR MANUFACTURING OF MORTAR OR CONCRETE. AGGREGATES ARE THE IMPORTANT CONSTITUENT IN CONCRETE. AGGREGATES ARE GRANULAR MATERIAL DERIVED FROM THE MOST PART OF THE NATURAL ROCK, CRUSHED STONES, NATURAL GRAVELS OR SAND AGGREGATES ARE GENERALLY OCCUPY ABOUT 7080 % OF VOLUME OF A CONCRETE AND THEREFORE BE EXPECTED TO HAVE AN IMPORTANT INFULENCE ON IT’S PROPERTIES Crushed Stone: Quarried from a ledge rock Gravel: ◦ Mined or dredged from natural deposits Mining or Blasting Crushing ◦ Primary ◦ Secondary Sizing ◦ Gradation ◦ Fines Testing (QC/QA) Recycled Concrete: ◦ Quarried from pavements or other sources Slag or Foundry Sand: ◦ Mined from industrial stockpiles GOOD QUALITIES OF AN IDEAL AGGREGATE: An ideal aggregate used for the manufacturing of concrete and mortar, should meet the following requirements. (1) It should consist of natural stones, gravels and sand or in various combinations of these materials. (2) It should be hard, strong and durable. (3) It should be dense, clear and free from any coating. (4) It should be free from injurious vegetable matters. (5) It should not contain flaky (angular) and elongated pieces. 8 PHYSICAL PROPERTIES PARTICLE SIZE DISTRIBUTION SPECIFIC GRAVITY & WATER ABSORPTION CLAY AND FRIABLE PARTICLES FLAKINESS & ELONATION LOS ANGELES ABRASSION AGGREGATE CRUSHING VALUE AGGREGATE IMPACT VALUE TEN PERCENT FINES VALUE SOUNDNESS TEST NAME APPLICABLE STANDARD SPECIFICATION LIMIT Water absorption ASTM C 127/128 Max 2 % Flakiness BS 812 Part 105.1 Max 25% Elongation Bs 812 Part 105.2 Max 25% Clay lump ASTM C142 Max 1% Acid Soluble Sulphate BS 812 Part 116 Max 0.3% Acid Soluble Chloride Bs 812 Part 117 Max 0.03% Sand Equivalent ASTM D2419 Min 75% Soundness ASTM C88 Max 12% Impact Value BS 812 Part 112 Max 30% 10% fine Value Bs 812 Part 111 Min 100KN CLASSIFICATION BASED ON SOURCE: >Natural aggregates: This kind of aggregate is taken from natural deposits without changing their nature during the process production such as crushing and grinding. >Manufactured (synthetics) aggregates: This is a kind of man-made materials produced as a main product or an industrial byproduct. Some example are blast furnace slag, air cooled slag and broken bricks. Synthetics aggregates are produced by thermally processed materials such as expanded clay and shale used for making light weight concrete. 11 a)CLASSIFICATION BASED ON SIZE: >Coarse aggregate: Aggregate which retained on the No.4 (4.75mm) sieve. The function of the coarse aggregate is to act as the main load-bearing component of the concrete. >Fine aggregate: Aggregate passing No.4(4.75mm) sieve and predominantly retained on the No.200 (75µ) sieve. The fine aggregate serve the purpose of filling all the open space in between the coarse particles. 12 CLASSIFICATION BASED ON UNIT WEIGHT: Aggregates are classified as Light-weight, Heavy-weight and Normal-weight aggregate depending on weight and specific gravity. AGGREGATE SPECIFIC GRAVITY Mg/m3 UNIT WEIGHT BULK EXAMPLE DENSITY(Mg /m3 Normalweight 2.5-2.7 23-26 15.2016.80 sand Heavyweight 2.8-2.9 25-29 >20.80 Scrap iron 12 <11.20 dolomite Lightweight 13 CLASSIFICATION BASED ON SHAPE: The shape of aggregates is an important characteristic, since it affect the workability of concrete. CLASSIFICATION EXAMPLE Rounded River or seashore gravels Partially Rounded Pit sands & Gravels Angular Crushed Rocks Flaky Laminated rocks 14 Rounded ANGULAR ELONGATED Flaky 15 CLASSIFICATION BASED ON SUFACE TEXTURE: Surface texture is a measure of the smoothness and roughness of aggregate. The grouping of aggregate is broad and is based on visual examination of the specimen. As per IS:3831970 the aggregates are classified into five groups, namely, Glassy, Smooth, Granular, Crystalline, Honeycombed and Porous. CLASSIFICATION EXAMPLES Glassy Black flint Smooth Gravel, Marble Granular Sandstone Rough Basalt Crystalline Granite 16 SMOOTH ROUGH 17 THIS TEST COVERS THE DETERMINATION OF PARTICLE SIZE DISTRIBUTION OF COARSE AND FINE AGGREGATES. A SAMPLE OF DRY AGGREGATES OF KNOWN MASS IS SEPARATE THROUGH A SERIES OF SIEVES OF PROGRESSIVELY SMALLER OPENING FOR DETERMINATION OF PARTICLE SIZE DISTRIBUTION. SPECIFIC GRAVITY AND WATER ABSORPTION OF COARSE & FINE AGGREGATES ASTM C 127&128 & BS 812 PART 2 :1995 DETERMINE THE BULK AND APPARENT SPECIFIC GRAVITIES AND WATER ABSORPTION OF COARSE AND FINE AGGREGATES. ABSORPTION IS THE PROCESS BY WHICH WATER IS DRAWN INTO AND TRENDS TO FILL THE PERMEABLE PORES IN A POROUS SOLID BODY. FLAKINESS INDEX THE FLAKINESS INDEX OF AN AGGREGATE SAMPLE IS FOUND BY SEPERATING THE FLAKY PARTICLES AND EXPRESSING THEIR MASS AS A PERCENTAGE OF THE MASS OF SAMPLE TESTED ELONGATION INDEX THE ELONGATION INDEX IS FOUND BY SEPERATING THE ELONGATED PARTICLE AND EXPRESSING THEIR MASS AS A PERCENTAGE OF THE MASS OF SAMPLE TESTED THIS METHODCOVERS A PROCEDURE FOR TESTING SIZES OF COARSE AGGREGATE SMALLER THAN 37.5 MM FOR RESISTANCE TO DEGRADATION USING THE LOS ANGELES MACHINE. AGGREGATE CRUSHING VALUE & AGGREGATE IMPACT VALUE BS 812 PART 110:1990 & BS 812 PART 112:1990 ACV-THIS METHOD GIVES A RELATIVE MEASURE OF THE RESISTANCE OF AN AGGREGATE TO CRUSHING UNDER A GRADUALLY APPLIED COMPRESSIVE LOAD AIV-THIS METHOD GIVES A RELATIVE MEASURE OF THE RESISTANCE OF AN AGGREGATE TO SUDDEN SHOCK OR IMPACT We collect sample from different source and different size to find out quality of aggregate. We conduct different test as per international standard. Following test was carried out. PARTICLE SIZE DISTRIBUTION AGGREGATE LOSS ANGELES ABRASION AGGREGATE ELONGATION INDEX AGGREGATE FLAKINESS INDEX AGGREGATE CHLORIDE CONTENT AGGREGATE SULPHATE CONTENT Sieve size National Quarry DOHA QUARRY RAJ STONE 28mm 100% 100% 100% 20mm 97% 96% 95.6% 14mm 30% 31% 37.9% 10mm 2.0% 1.2% 3.4% 6.3mm 0% 1% 0.7% 5.0 0% 0% 0.6% 100 90 95.6 100 80 70 60 Passing % 50 40 37.9 30 20 10 0.6 0.7 3.4 0 5mm 6.3mm 10mm Sieve Sizes 14mm 20mm 28mm SOURCE NAME NATIONAL QUARRY DOHA QUARRY RAJ STONE LOSS AGGELES ABRASION 12% 13.9% 10% ELONGATION INDEX 23% 29% 14% FLAKINESS ` INDEX 10% 26% 8% CHLORIDE CONTENT 0.01 0.006 0.01 SULPHATE CONTENT 0.05 0.007 0.04 IN GEOLOGY, ROCK IS A NATURALLY OCCURRING SOLID AGGREGATES OF ONE OR MORE MINERALS. THE SOLID MINERAL MATERIAL FORMING PART OF THE SURFACE OF THE EARTH AND OTHER SIMILAR PLANETS, EXPOSED ON THE SURFACE OR UNDERLAYING THE SOIL. THREE GENERAL CLASSES OF ROCK: SEDIMENTARY ROCK METAMORPHIC ROCK IGNEOUS ROCK Sedimentary rock are formed from particles of sand ,shells, pebbles, and other fragments of material. Together, all these particles are called sediment. Generally ,sedimentary rock is fairly soft and may break apart or crumble easily. Metamorphic rocks are formed by subjecting any rock type sedimentary rock, igneous rock or another older metamorphic rock. Metamorphic rock are formed under the surface of the earth from the metamorphosis that occurs due to intense heat and pressure. Igneous rocks are formed from the solidification of magma rock material. Rocks formed by the cooling and solidifying of magma materials Based on Measurement Definition for field use UCS Measurements (Mpa) Extremely weak Gravel sized lumps crush between finger and thumb 0.6-1.0 Very Weak Can be break by pocket knife Weak Can be break by pocket knife with difficulty 5-25 Medium strong Can be fractured with a single firm blow of geological hammer 25-50 Strong Fracture on more then one blow of geological hammer 50-100 Very strong Require many blow of geological hammer for fracture Extremely strong Can be chipped with geological hammer 1-5 100-250 >250 These test methods cover the determination of the strength of intact rock core specimens in uniaxial and triaxial compression. The tests provide data in determining the strength of rock, namely: the uniaxial strength, shear strengths at different pressures and different elevated temperatures, angle of internal friction, (angle of shearing resistance), and cohesion intercept.