1. CONCRETE MAKING MATERIALS –II: AGGREGATE

2. CLASSIFICATION OF AGGREGATES
ACCORDING TO GEOLOGICAL ORIGIN
NATURAL AGGREGATE
ARTIFICIAL AGGREGATE
ACCORDING TO SIZE
FINE AGGREGATE
COARSE AGGREGATE
ALL-IN-AGGREGATE
SINGLE-SIZE-AGGREGATE
ACCORDING TO SHAPE
ROUNDED AGGREGATE
IRREGULAR AGGREGATES
ANGULAR AGGREGATE
FLAKY AND ELONGATED AGGREGATE
BASED ON UNIT WEIGHT
NORMAL-WEIGHT AGGREGATE
HEAVY-WEIGHT OR HIGH-DENSITY AGGREGATE
LIGHT-WEIGHT AGGREGATE

4. CHARACTERISTICS OF AGGREGATES
STRENGTH OF AGGREGATE
PARTICLE SHAPE AND TEXTURE
SPECIFIC GRAVITY
BULK DENSITY
POROSITY AND ABSORPTION OF AGGREGATES
MOISTURE CONTENT OF AGGREGATE
BULKING OF FINE AGGREGATE

5. Percentage of Bulking of Sand with Moisture Content

6. DETERMINation of PERCENTAGE OF BULKING by field test
Fill a sample of moist fine aggregate (sand) into a measuring cylinder in the normal manner. Note down the level, say h1.
Pour water into a measuring cylinder and completely cover the sand with water and shake it. Since the volume of the saturated sand is the same as that of the dry sand, the saturated sand completely offsets the bulking effect. Note down the level of sand, say h2.
Subtract the final level h2 from initial level h1 (i.e. h1-h2), which shows the bulking of sand under test.
Calculate percentage of bulking using formula given below.
Percentage of bulking = [(h1-h2)/h2]*100

7. DELETRIOUS SUBSTANCES IN AGGREGATES
Deleterious Materials – Aggregates shall not contain any harmful material, such as pyrites, coal, lignite, mica, shale or similar laminated material, clay, alkali, soft fragments, sea shells and organic impurities in such quantity as to affect the strength or durability of the concrete. Aggregates to be used for reinforced concrete shall not contain any material liable to attack the steel reinforcement. Aggregates which are chemically reactive with alkalis of cement are harmful as cracking of concrete may take place

9. SOUNDNESS OF AGGREGATE
The ability of the aggregate to resist excessive changes in volume due to changes in environmental conditions.

10. ALKALI-AGGREGATE REACTION (AAR) OR ALKALI-SILICA REACTIVITY (ASR)
REACTIVITY OF AGGREGATE
ALKALI CONTENT IN CEMENT
AVAILABILTY OF MOISTURE
TEMPERATURE CONDITIONS
ALKALI-AGGREGATE REACTION MECHANISM
CONTROL OF ALKALI-AGGREGATE REACTION

11. FINENESS MODULUS

12. GRADING AND SURFACE AREA OF AGGREGATE
GAP-GRADED AGGREGATE
GRADING LIMITS
CRUSHED SAND

14. GRADING LIMITS FOR FINE AGGREGATES IS: 383-1970
Sieve Size
Percentage of Passing For
Grading
Zone-I
Zone-II
Zone-III
Zone-IV
10 mm
100
4.75 mm
90 – 100
95 – 100
2.36 mm
60 – 95
75 – 100
85 – 100
1.18 mm
30 – 70
55 – 90
90 – 1000
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 – 15

15. GRADING LIMITS FOR SINGLE-SIZED COARSE AGGREGATE OF NOMINAL SIZE
Sieve Size (mm)
63 mm
40 mm
20 mm
16 mm
12.5 mm
10 mm
(Percentage of Passing) 80
100 – 63
85 to 100 40
0 to 30 20
0 to 5
0 to 20 16
12.5 10
0 to 45
4.75
0 to 10
2.36

16. GRADING LIMITS FOR COARSE AGGREGATE
Sieve Size (mm)
40 mm
20 mm
16 mm
12.5 mm
(Percentage of Passing for graded aggregate of nominal size, mm) 80
100 – 63 40
95 to 100 20
30 to 70 16
90 to 100
12.5 10
10 to 35
25 to 55
40 to 85
4.75
0 to 5
0 to 10
2.36

17. GRADING LIMIT OF ALL IN AGGREGATE
Sieve Size
Percentage of Passing For All-in-Aggregate
40 mm Nominal Size
20 mm Nominal Size
80 mm
100 –
40 mm
95 – 100
20 mm
45 – 75
4.75 mm
25 – 45
30 – 50
600 micron
8 – 30
10 – 35
150 micron
0 – 6