Soil lab (Aggregates Testing)

PAVEMENT MATERIALSPAVEMENT MATERIALS
ENGINEERINGENGINEERING
(CE-862)(CE-862)
Lec-02 (Lab 2)
Fall Semester 2016

Dr. Arshad Hussain
arshad_nit@yahoo.com , Office Room#111, Tel: 05190854163,
Cell: 03419756251
National Institute of Transportation (NIT)
National University of Science and Technology (NUST)
NUST Campus, Sector H-12, Islamabad

•Most common tests include:
• Crushing value test
• Impact value test
• Shape test
• Los Angeles abrasion
• Soundness test
• Sand equivalent

AGGREGATE CRUSHING VALUEAGGREGATE CRUSHING VALUE
• Metal measure
• Tamping rod
Below mentioned are its
specifications:
• Three sizes 75mm dia for 1/8
to 1/4 Size aggregate,
150mm dia for 3/8 to 3/4
Size aggregate
300mm dia for 1in to 2in
size aggregate
The aggregate crushing value indicates the ability of an
aggregate to resist crushing.
The lower the figure the stronger the aggregate, i.e. the
greater its ability to resist crushing.

AGGREGATE CRUSHING
VALUE
Aggregate passing IS sieve 12.5 mm and
retained on 10 mm sieve is generally used.
Oven dried aggregates are filled in the
measuring cylinder of 11.5cm dia. & 18.0cm
height in 3 equal layers, each layer being
subjected to 25 tamps with a tamping rod of
16mm dia and 45 to 60mm long.

AGGREGATE CRUSHING
VALUE
The crushing test apparatus consist of a
15cm dia open ended heavy steel cylinder,
plunger and a base plate.
Compression testing machine a load of 40
tonnes is applied in 10 min. crushed
aggregate Sieved through 2.36 mm sieve.

 Agg crushing value > 35 weak for pavement.
 Agg crushing value < 10 exceptionally strong.
 For majority of aggregates the impact value and
crushing value are numerically similar.
 Rock group Crushing value Impact value
Basalt 14 15
Granite 20 19
Lime stone 24 23
Quartzite 16 21
AGGREGATE CRUSHING
VALUE

AGGREGATE IMPACTVALUE
A base, which helps in supporting
the columns to form a rigid
framework around the quick release
trigger mechanism for ensuring the
effective free fall of the hammer
during test.
The hammer is offered with locking
arrangement and the free fall can be
easily adjusted through the 380+
5mm.
cylindrical cup, with the metal
measure 75 mm dia x 50 mm high
and tamping rod.
Satisfactory resistance to crushing under roller during
construction. Adequate resistance to surface abrasion
under traffic.

IMPACT VALUE
 Due to traffic loads the road stones are subjected to impact.
 IS sieves 12.5 mm,10 mm & 2.36 mm.
 Cylindrical steel cup of dia 10.2 cm & depth 5 cm.
 Metal hammer of weight 13.5 to 14 kg. Height of fall 38 cm.
Cylindrical measure with internal dia 7.5 cm & depth 5 cm.
 Metal tamping of 1 cm dia.23 cm long.
< 10 % exceptionally strong.
10 - 20 % strong.
20 - 30 % satisfactory. > 35 % weak.

ELONGATION & FLAKINESS INDEXELONGATION & FLAKINESS INDEX
 When the length is more than 1.8 of the mean dimension,
then the aggregate particles are considered elongated.
The aggregate particles are to be flaky, if the thickness is
less than the 0.6 of their mean dimension.

Size of aggregates
Weight of
fraction
consisting
of at least
200
pieces,g
Thickness
gauge size,
mm
Weight of
aggregates
in each
fraction
passing
thickness
gauge,mm
Length
gauge
size,
mm
Weight of
aggregates
in each
fraction
retained on
length
gauge,mm
Passing
through IS
Sieve, mm
Retained
on IS
Sieve,
mm
1 2 3 4 5 6 7
63 50 W1 23.90 X1 – –
50 40 W2 27.00 X2 81.00 Y1
40 31.5 W3 19.50 X3 58.00 Y2
31.5 25 W4 16.95 X4 – –
25 20 W5 13.50 X5 40.5 Y3
20 16 W6 10.80 X6 32.4 Y4
16 12.5 W7 8.55 X7 25.5 Y5

LOS ANGELES ABRASION TEST
Start with fraction retained on No. 12 sieve

Sample submerged in magnesium or sodium sulfate—causes
salt crystals to form in the aggregate pores
SOUNDNESSSOUNDNESS TESTTEST

SAND EQUIVALENTSAND EQUIVALENT
SE = (Height of Sand/Height of
Clay)100
This is a test to determine the amount of
clay in fine aggregate.
Aggregate passing a No. 4 sieve is
agitated in a water-filled transparent
cylinder. Liquid is water and flocculating
agent. After settling, the sand separates
from the flocculated clay. Measure each.

Soil lab (Aggregates Testing)

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Viewers also liked

Viewers also liked (20)

Similar to Soil lab (Aggregates Testing)

Similar to Soil lab (Aggregates Testing) (20)

More from Muhammad Faisal

More from Muhammad Faisal (13)

Recently uploaded

Recently uploaded (20)

Soil lab (Aggregates Testing)