Civil Engineering Materials PDF Lecture Notes - Aggregate Properties

Civil Engineering Materials CIVL1012- Week 5 Aggregate Properties- Part II Dr. Raheleh Alizadeh Angelo DelZotto School of Construction Management  Specific Gravity The mass of a material divided by...

Civil Engineering Materials CIVL1012- Week 5 Aggregate Properties- Part II Dr. Raheleh Alizadeh Angelo DelZotto School of Construction Management  Specific Gravity The mass of a material divided by the mass of water whose volume is equal to the volume of the material at a specific temperature, or Mass of Solid Volume G= Mass of Water Volume G =  / w w : Density of water at specified temperature@ 4C, w: 1000 kg/m3 = 1 g/ml = 1 g/cm3 Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 2  Determining Specific Gravity Mass Solid Volume Mass Solid Mass Water Mass Water Volume Determine by weighing in air Mass Solid Mass Water Determine by (weight in air - weight in water) Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 3  Determining Specific Gravity Mass of stone=150 gr Initial water level=200 mL(cm3) Water level after adding stone= 260 mL (cm3) 150 Bulk Relative Density= =2.5 60 George Brown Civil Engineering Lab Notes 4  Effects of Voids Voids on the surface of aggregates create multiple definitions of specific gravity Apparent Bulk, Dry Bulk, SSD Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 5  Apparent Specific Gravity Functional definition Volume of aggregate Mass, oven dry agg Gsa = Vol of agg Apparent Stone Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 6  Bulk Specific Gravity, Dry Functional definition Surface Voids Mass, oven dry Gsb = Vol of agg. + surface voids Bulk Stone Vol. of water-perm. voids Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 7  Bulk Specific Gravity, SSD(saturated surface dry) **Used for concrete mix design** Functional definition Surface Voids Mass, SSD Gs,bssd = Vol of agg. + surface voids Bulk, saturated surface dry Stone Vol. of water-perm. voids Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 8  Coarse Aggregate Specific Gravity (ASTM C127) Note: Fine aggregate specific gravity test is very similar to coarse aggregate test procedure with few differences. It will be explained in lab. Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc/ George Brown Civil Engineering Lab Notes 9  Bulk Unit Weight & Voids in Aggregates Bulk unit weight is the weight of aggregate required to fill a “unit” volume. Typical units are cubic meters and cubic feet. Loose Compacted Shovel dry aggregate into container Shovel dry aggregate into container Limit drop < 2” above rim of Fill to 1/3 of volume container Rod 25 times Strike off aggregate level with top of Repeat 3x to fill container container Determine weight of aggregate in Strike off aggregate level with top of container, WS container Compute unit weight Determine weight of aggregate in container, WS Compute unit weight Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 10  Bulk Unit Weight & Voids in Aggregates Where: = the bulk unit weight of aggregate Ws = weight of aggregate V = volume of the container Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 11  Example 5: Bulk Unit Weight & Voids in Aggregates Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 12  Blending Aggregate Gradations Reasons for Blending Obtain desirable gradation Single natural or quarried material not enough Economical to combine natural and process materials Trial and Error Numerical Method Basic Formula Aggregates Trial & Error Method Pi = Ai a + Bi b + Ci c…. For sieve size i, Pi = % in the blend that passes sieve size i, Ai, Bi, Ci … = % of stockpile A, B, C that passes sieve size i, a, b, c … = decimal fraction by weight of each stockpile in the blend Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 13  Example 4: Blending Aggregate Sieve size (mm) 9.5 4.75 2.36 1.18 0.600 0.300 0.150 A % passing 100 98 65 43 21 12 5 Sieve size (mm) 9.5 4.75 2.36 1.18 0.600 0.300 0.150 B % passing 100 82 63 25 12 6 1 Sieve size (mm) 9.5 4.75 2.36 1.18 0.600 0.300 0.150 C % passing 100 71 52 44 38 22 10 Fractions of aggregate in the Blend: A: 25% B: 25% C:50% Find P 0.600? Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 14  Properties of Blended Aggregates G1, G2, G3,…: Specific gravities of fraction 1,2,3,… P1, P2, P3,…: Decimal fractions by weight of aggregate 1,2,3,… (Angularity, Absorption, Strength And Modulus) X: the test value for the aggregate blend Applies to whole agg. xi: the test result for stockpile i Pi: the percent of stockpile i in the blend Applies to coarse OR fine pi: the percent of stockpile i that either passes or is retained on the dividing sieve Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 15  Example 5: Blending Aggregate Aggregate from three sources having bulk specific gravities of 2.753, 2.649 and 2.689 were blended at a ratio of 70:20:10 by weight, respectively. What is the bulk specific gravity of the aggregate blend? 1 𝐺= 𝑃1 𝑃2 𝑃3 + + 𝐺1 𝐺2 𝐺3 1 𝐺= = 2.725 0.7 0.2 0.1 + + 2.753 2.649 2.689 Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 16  Example 6: Blending Aggregate Coarse aggregate from two stockpiles having coarse aggregate angularity (crushed faces) of 40% and 90% were blended at a ratio of 30:70 by weight, respectively. What is the percent of crushed faces of the aggregate blend? 𝐶𝑟𝑢𝑠ℎ𝑒𝑑 𝑓𝑎𝑐𝑒𝑠 𝑜𝑓 𝑡ℎ𝑒 𝑏𝑙𝑒𝑛𝑑 = 0.3 40 + 0.7 90 = 75% Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 17  Example 7: Blending Aggregate Mamlouk/Zaniewski, Materials for Civil and Construction Engineers, Fourth Edition. Copyright © 2017 Pearson Education, Inc. 18 Grading Curve on Semi-log Graph Sieve size Amount Retained 25 0 12.5 0 9.5 21 4.75 104 2.36 79 1.18 78 0.6 51 0.3 78 0.15 82 0.075 39 pan 5 19  Amount Cum. Amount Cum % Amount Sieve size Retained Retained Retained % Passing 25 0 0 0.0 100 12.5 0 0 0.0 100 9.5 21 21.0 3.9 96.1 4.75 104 125.0 23.3 76.7 2.36 79 204.0 38.0 62 1.18 78 282.0 52.5 47.5 0.6 51 333.0 62.0 38 0.3 78 411.0 76.5 23.5 0.15 82 493.0 91.8 8.2 0.075 39 532.0 99.1 0.9 pan 5 537 20  120 100 Percentage Passing 80 60 40 20 0 0.01 0.1 1 10 100 Sieve Size (mm) 21 22 23  120 100 80 % Passing 60 UL LL 40 Aggregate Sample 20 0 0.1 1 10 100 Sieve size (mm) 24  Reduce sample amount to the test size Sample Splitter Quartering George Brown Civil Engineering Lab Notes 25  Cleanness and Deleterious Materials Aggregate may contain clay, shale, organic matter and other deleterious materials such as coal. Sand Equivalency Test: A sample of sand and flocculating agent is poured into a graduated cylinder. The cylinder is agitated to permit all the clay in the sample to be released from the sand and go into suspension in the flocculated agent. The sample is allowed to rest for a specified period of time. Sand settles much faster than clay and a distinct interface develops between the sand and clay. The heights to the top of the sand and the top of the clay are measured ℎ𝑒𝑖𝑔ℎ𝑡𝑠 𝑡𝑜 𝑡ℎ𝑒 𝑡𝑜𝑝 𝑜𝑓 𝑡ℎ𝑒 𝑠𝑎𝑛𝑑 SE(sand equivalency)=100* ℎ𝑒𝑖𝑔ℎ𝑡𝑠 𝑡𝑜 𝑡ℎ𝑒 𝑡𝑜𝑝 𝑜𝑓 𝑡ℎ𝑒 𝑐𝑙𝑎𝑦 26 https://images.app.goo.gl/9wBh2iYbyvd6eCPz7 27  HW#3 Due Date: Oct 8, 2024, 6:00pm Online via Brightspace Questions?