EXPERIMENT NO AIM :- To perform water absorption test on given aggregate sample by oven drying method. APPARATUS :- Measuring weights , aggregates immersed in water for 24 hrs , oven . FORMULA :- Water absorption in % = [ ( W 1 - W 3 ) / ( W 2 - W 1 ) ] x 100 Where Weight of empty container = W 1 = _____ Gm Weight of soaked aggregate + Weight of container = W 2 = _____ Gm Weight of oven dried aggregate + Weight of container = W 3 = _____ Gm FIGURE :- THEORY :- Stones having higher water absorption values are porous and hence weak . They are generally suitable unless found acceptable based on crushing and grinding . The sample is weighted on water and the buoyant weight is found . The aggregate is taken out and weighted after the surface is dried . The specific gravity can be calculated by diving dry weight of aggregate by weight of equal volume of water. The water absorption is expressed as percentage water absorption in terms of oven dried weight of aggregate . The specific gravity of rock varies from 2.6 to 2.9 . Rock specimen having more than 0.6 percent of water absorption are considered unsatisfactory values found acceptable based upon strength tests . However slightly higher value of porosity may be acceptable for aggregate used in bitumen pavement construction of the aggregate are otherwise suitable PROCEDURE :- 1)About 2 Kg of dry aggregate sample is placed in wire basket and immersed in water for 24 Hrs. 2) The weight of the sample is taken . 3)The aggregate sample is placed in oven ( 100 – 110 0 C ) for 24 Hrs. 4)After complete drying dry weight of the sample is taken . 5)Percentage of water absorption is calculated . OBSERVATION :-
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EXPERIMENT NO
AIM :- To perform water absorption test on given aggregate sample by oven drying
method. APPARATUS :-
Measuring weights , aggregates immersed in water for 24 hrs , oven .
FORMULA :-
Water absorption in % = [ ( W1- W3 ) / ( W2- W1 ) ] x 100
Where
Weight of empty container = W1 = _____ Gm
Weight of soaked aggregate + Weight of container = W2 = _____ Gm
Weight of oven dried aggregate + Weight of container = W3 = _____ Gm
FIGURE :-
THEORY :- Stones having higher water absorption values are porous
and hence weak . They are generally suitable unless found acceptable based
on crushing and grinding . The sample is weighted on water and the
buoyant weight is found . The aggregate is taken out and weighted after the
surface is dried . The specific gravity can be calculated by diving dry
weight of aggregate by weight of equal volume of water.
The water absorption is expressed as percentage water absorption in terms
of oven dried weight of aggregate . The specific gravity of rock varies from
2.6 to 2.9 . Rock specimen having more than 0.6 percent of water
absorption are considered unsatisfactory values found acceptable based
upon strength tests . However slightly higher value of porosity may be
acceptable for aggregate used in bitumen pavement construction of the
aggregate are otherwise suitable
PROCEDURE :-
1)About 2 Kg of dry aggregate sample is placed in wire basket and
immersed in water for 24 Hrs.
2) The weight of the sample is taken .
3)The aggregate sample is placed in oven ( 100 – 110 0
C ) for 24 Hrs.
4)After complete drying dry weight of the sample is taken .
5)Percentage of water absorption is calculated .
OBSERVATION :-
Weight of empty container = W1 = _____ Gm
Weight of soaked aggregate + Weight of container = W2 = _____ Gm
Weight of oven dried aggregate + Weight of container = W3 = _____ Gm
CALCULATION :-
Water absorption in % = [ ( W1- W3 ) / ( W2- W1 ) ] x 100
RESULT :-
Percentage of water absorption for a given sample of aggregate is found to
be _________ %.
PRECAUTION :-
1) The aggregate must be immersed properly in water for 24 Hrs .
2)The water from surface of aggregate must be dried .
3)Weight the aggregate carefully in spring balance.
DISCUSSION :-
Rock specimen having more than 0.6 % water absorption
values are considered unsatisfactory unless found acceptable based on
strength test . However slightly higher value of porosity may be acceptable
for aggregate used in bituminous pavement construction if aggregate is
found otherwise suitable.
EXPERIMENT NO
AIM :- To determine flakiness index of aggregate .
APPARATUS :-
Aggregate, set of sieves, tray, weight box etc.
FORMULA :-
flakiness index = [ ∑ w / ∑ W ] X 100
Where,
w = Weight of aggregate passing
W = Weight of aggregate retained
FIGURE :-
THEORY :-
The principal shape of Aggregate mass is determine by the
percentage of flaky and elongated particles contained in it and by its
angularity . The evaluation of shape of particles made of flakiness index
and elongated index and angularity numbers .
The flakiness index of aggregate is the percentage by
weight of aggregate particles whose least dimensional thickness is less
than 0.6 times their mean dimension. The test is applicable to size larger
than 6.3 mm standard thickness is used to guage the thickness of sample .
PROCEDURE :-
1) The sample of aggregate to be tested is sieved through a set of sieves and
separated into a specified size ranges.
2) Now to separate the flaky material , the aggregate which pass through
the appropriate elongated slot of thickness guage are found .The width of
the appropriate slot would be 0.6 of the average of the sieve size range.
3) The flaky material passing the appropriate slot from each size range of
test aggregate are added up and let the weight be W1.
4) If the total weight of sample take from different size range is w, the
flakiness index is given by
Flakiness Index = [ W1 / W ] X 100
OBSERVATION TABLE :-
Sr
No
Sieve
No.
(mm)
Weight
Retained
W(Gm)
Weight of
Aggregate passing
appropriate slot (gm)
∑ W
(gm)
F.I. = [ ∑ w / ∑ W ]
X 100
1 2 3 4 5 6
CALCULATION :-
flakiness index = [ ∑ w / ∑ W ] X 100
RESULT :-
The Flakiness Index of a given aggregate sample is found to be _______ %.
DISCUSSION :-
Elongated aggregate are less workable , they are also likely to
break under smaller loads than the aggregate which are spherical or cubical
, flakiness index values in excess of 15 % are generally consider
undesirable . If is desirable that flakiness index of aggregate used in road
construction is less than 15 % and normally does not exceed 25 %.
APPLICATION :-
If the flakiness index is more than the aggregate can take less
loads and are liable to fail under less load . So it is not desirable to use
aggregate of higher flakiness index is permanent .
EXPERIMENT NO
AIM:- To determine specific gravity of a given aggregate sample by Pycnometer
APPARATUS:-
Pycnometer balance, Weight –box, aggregate
FORMULA:-
(W2-W1)
Specific gravity =
(W2-W1) – (W3-W4)
Where
Weight of empty Pycnometer = W1 gms
Weight of Pycnometer + aggregate = W2 gms
Weight of Pycnometer + aggregate +Water = W3 gms
Weight of Pycnometer + Water = W4 gms
Weight of aggregate = (W2-W1) gm.
Weight of equal volume of distilled water = (W2-W1) – (W3-W4) gms
FIGURE :-
THEORY :-
Specific gravity is the ratio of the weight of given volume of
dry aggregate to the weight of equal volume of distilled water.
Let (i) Weight of empty Pycnometer = W1 gms
(ii) Weight of Pycnometer + aggregate = W2gms
(iii)Weight of Pycnometer + aggregate +Water = W3 gms
(iv)Weight of Pycnometer + Water = W4 gms
Weight of aggregate = (W2-W1) gm.
Weight of equal volume of distilled water = (W2-W1) – (W3-W4) gms
(W2-W1)
Specific gravity =
(W2-W1) – (W3-W4)
PROCEDURE:-
(1)Make the Pycnometer dry &Weight it with its cap &ring
(2)Unscrew the cap &Rut 200 gms of aggregate &Weight it
(3)Add water to the top of brass cap. Remove all the trapped dir by pouring
additional water
(4)Dry the Pycnometer & fell it to the top with & weight it
(5)Repeat the Procedure
(6)Find the average specific gravity by using formula
OBSERVATION TABLE :-
SR
No
Weight of
aggregates
Weight of
empty
pycnometer
(W1)gm
Weight of
pycnometer
+aggregate
(W2) gm
Weight of
pycnometer
+water
+aggrate
(W3) gm
Weight of
Pycnometer
+water
(W4) gm
Specific
gravity
1
2
3
4
Average specific gravity =
SAMPLE CALCULATION:-
(W2-W1)
Specific gravity =
(W2-W1) – (W3-W4)
G =
RESULT:-
Average specific gravity is found to be ___________
PRECAUTIONS:-
(1) Take the weight carefully.
(2) Pycnometer must be dry for use.
(3) There should be no air bubble inside the bottle.
DISCUSSIONS:-
The value of specific gravity of aggregate is required for
concrete mix design and useful for calculating water content. Stone having
higher water absorptions values are porous and this weaker specific gravity
also indicates strong specimen.
EXPERIMENT NO
AIM: - To determine the Flash &Fire point for the sample of bitumen taken.
APPARATUS: - Flash point set up, thermometer, heating arrangement etc.
FIGURE:-
THEORY: - This test gives up the indications of the critical temperature
at which the suitable precautions should be taken while heating bitumen .
Flash Point:-The temperature at which the volatile material i.e. bitumen
emits vapours and it catches fire momentarily in the form of flash.
Fire Point :-The temperature at which the volatile nature i.e. bitumen emits
vapours get ignited and burns
PROCEDURE: -
The material is filled up to the mark of filling in the cup
liquid is placed too dose to the cup .All accessories including thermometers
are fixed .The sample is heated at rate of 50to60 0C/min. The first flash as
applied at test 170 C below actual flash point.
The flash point as taken as the temperature reading on the
thermometer at the time of applications of flame that causes bright flash in
the interior of cup. The heating is continuous till the material’s ignited. This
gives the fire point.
RESULT: - i) Flash Point =
ii) Fire Point =
DISCUSSION:-
The bitumen material leaves out volatile at high temperature
depending up on their grades. These volatile catch fire causing a flash. This
condition is very hazardous.
PRECAUTION: -
If the candle is used as a flame then it should be seen that
flame should not fall in the bitumen, otherwise it would give flame at less
Temperature as wax will catch fire.
APPLICATION: -
Bitumen is used in construction of pavements so the flash & fire
point is determined to check for the amount of heating to avoid any
accidents.
EXPERIMENT NO
AIM:- To Determine the impact value of a given a aggregate sample