green roads (exp).docx

8/18/2019 Green Roads (Exp).docx

1/24

1. AIM: To determine the softening point of bitumen/ tar.

APPARATUS:

(i) The ring and ball apparatus consisting of

(a) Steel balls-two numbers each of 9.5 mm diameter weighing 3.5 ± .5

g.

(b) !rass rings-two numbers each ha"ing depth of #.$ mm. The inside

diameter at bottom and top is %5.9mm and %&.5 mm respecti"el'.

(c) !all guides to guide the mo"ement of steel balls centrall'.

(d) Support -that can hold rings in position and also allows for suspension of

a thermometer. The distance between the bottom of the rings and the top

surface of the bottom plate of the support is 5mm.

(i) Thermometer that can read up to % * with an accurac' of . *.

(ii) !ath–heat resistant glass bea+er not less than ,5 mm in diameter

%mm deep.


2/24

(iii) Stirrer

T!"R#: The Softening oint of bitumen or tar is the temperature at which the

substance attains particular degree of softening. s per 0S1 33$-%9,2 it is the

temperature in * at which a standard ball passes through a sample of bitumen in a

mould and falls through a height of .5 cm2 when heated under water or gl'cerine

at specified conditions of test. The binder should ha"e sufficient fluidit' before its

applications in road uses. The determination of softening point helps to +now the

temperature up to which a bituminous binder should be heated for "arious road use

applications. Softening point is determined b' ring and ball apparatus.

PR"$!%UR!:

(i) reparation of test sample1 4eat the material to a temperature between

&5-% * abo"e its softening point stir until2 it is completel' fluid and free

from air bubbles and water. 0f necessar'2 filter it through 0S sie"e 3. lace

the rings pre"iousl' heated to a temperature appro6imating to that of the

molten material2 on a metal plate which has been coated with a mi6ture of

e7ual parts of gl'cerine and de6trine. fter cooling for 3 minutes in air2

le"el the material in the ring b' remo"ing the e6cess material with awarmed2 sharp +nife.

(ii) ssemble the apparatus with the rings thermometer and ball guides in

position

(iii) 8ill the bath with distilled water to a height of 5mm abo"e the upper

surface of the rings. The starting temperature should be 5 *.

ote1 :se gl'cerine in place of water if the softening point is e6pected to be

abo"e , * the starting temperature ma' be +ept 35 *.

(i") ppl' heat to the bath and stir the li7uid so that the temperature rises

at a uniform rate of 5 ± .5 * per minute.


3/24

(") s the temperature increases the bituminous material softens and the

balls sin+ through the rings carr'ing a portion of the material with it.

("i) ote the temperature when an' of the steel balls with bituminous

coating touches the bottom plate.

(i) ;ecord the temperature when the second ball touches the bottom plate.

The a"erage of the two readings to the nearest .5* is reported as

softening point.

PR!$AUTI"&S:

(i) *

R!$"MM!&%!% AU!:


4/24

Softening point indicates the temperature at which binders possess the same

"iscosit'. !ituminous materials do not ha"e a melting point. ;ather2 the

change of state from solid to li7uid is gradual o"er a wide range of

temperature. Softening point has particular significance for materials to be

used as =oint and crac+ fillers. 4igher softening point ensures that the' will

not flow during ser"ice. 4igher the softening point2 lesser the temperature

susceptibilit'. !itumen with higher softening point is preferred in warmer

places.


5/24

*. AIM: To determine the flash and fire point of bitumen

APPARATUS:

ens+'-?arten *losed Tester2 Thermometer

T!"R#:

!ituminous material lea"e out "olatiles at high temperatures depending upon

their grade. These "olatile "apours catch fire causing a flash. The flash point

is the lowest temperature at which flash occurs due to ignition of "olatile

"apours when a small flame is brought in contact with the "apours of abituminous product2 graduall' heated under standardised condition. @hen

bituminous material is further heated to a higher temperature2 the material

itself catches and continues to burn the lowest temperature causing this is

the fire point. 8ire point is alwa's higher than flash point.

The flash point of a material is the lowest temperature at which "apour of a

substance momentaril' ta+e fire in the form of flash.

The fire point is the lowest temperature at which the material gets ignited

and burns under specific conditions of test.

PR"$!%UR!:


6/24

ll parts of cup are cleaned and dried thoroughl'. ?aterial is filled into cup

upto filling mar+. Aid is placed to close the cup in a closed s'stem. ll

accessories including thermometer of specified range are suitabl' fi6ed.

!itumen sample is then heated. Stirring is done at regular inter"als. The test

flame is lit and applied at inter"als depending upon e6pected flash and fire

point. 8irst application is made at about %&* below actual flash point and

then at e"er' %*. Stirring is discontinued during the application of the test

flame.

R!SUT:

8lash point of bitumen >

8ire point of bitumen >

R!$"MM!&%!% AU!S:

The minimum "alue of flash point b' ens+' ?artens closed t'pe apparatus

is %&5* for all grades of bitumen.

+. AIM: To determine the "iscosit' of bitumen using tar "iscometer


7/24

APPARATUS:

Tar "iscometer2 cup2 "al"e2 recei"er2 thermometer etc.

T!"R#:

Biscosit' is the in"erse of fluidit'. The degree of fluidit' at the application

temperature greatl' influences the abilit' of bituminous material to spread2

penetrate into "oids and also coat the aggregate and hence affect thestrength and characteristics of resulting pa"ing mi6es. t high fluidit' or low

"iscosit'2 bitumen binder simpl' lubricates the aggregate particles instead of

pro"iding an uniform film thic+ness for binding action. Aow fluidit' or high

"iscosit' does not enable the bitumen to coat the entire surface of aggregate

in the mi6 easil' and also resists the compacti"e effort and resulting mi6 is

heterogeneous in character.

PR"$!%UR!:

The tar cup is properl' le"elled and water in the bath is heated to the test

temperature. Stirring is also continued. ?aterial is heated to * abo"e the

test temperature and material is allowed to cool.


8/24

of the tar "iscometer until le"elling peg on "al"e rod is =ust immersed.

;ecei"er is placed under the orifice. Bal"e is opened after appl'ing +erosene

in the recei"er. Stop watch is started when c'linder records 5 ml. Time is

recorded for flow upto a mar+ of %ml.

R!SUT:

iscosit' of cutbac+ bitumen > CCCseconds.

R!$"MM!&%!% AU!S:

*utbac+ bitumen

S*2?*2;* of grades % 3 $ 5

Drifice siEe (mm) $. $. %. %. %. %.

Test Temperatures(*) 5 5 5 5 $ $

Biscosit' ;anges 5-&5 3-5 %- 5-&5 %$-$5 #-%$

PENETRATION VALUE OF BITUMEN


9/24

,. AIM:

(i) To determine the consistenc' of bituminous material

(ii) To assess the suitabilit' of bitumen for use under different climatic

conditions and "arious t'pes of construction.

APPARATUS:

(i) *ontainer1 flat bottomed c'lindrical metallic dish 55 mm in diameter

and 35 mm in depth is re7uired. 0f the penetration is of the order of 5 or

more2 dish of &mm diameter and $5mm depth is re7uired.

(ii) eedle1 straight2 highl' polished2 c'lindrical hard steel rod.

(iii)@ater bath1 @ater bath maintained at 5 ± .% *2 containing not less

than % litres of water2 the sample being immersed to a depth not less than

% mm from top supported on perforated shelf not less than 5 mm from

bottom of the bath.


10/24

(i")Transfer dish or tra'1 Should pro"ide support to the container should

not roc+ it. 0t should be of such capacit' as to completel' immerse container

during test.

(") enetration apparatus1 Should be such that it allows needle to penetrate

without much friction is accuratel' calibrated to gi"e results in one tenth of

a millimeter.

("i)Thermometer1 ;ange - $$ * and in readable upto . *.

("ii)Time measuring de"ice1 @ith an accurac' of l second.

T!"R#:

enetration "alue is a measure of hardness or consistenc' of bituminous

material. 0t is the "ertical distance tra"ersed or penetrated b' the point of a

standard needle in to the bituminous material under specific conditions of

load2 time and temperature. This distance is measured in one tenths of a

millimeter. This test is used for e"aluating consistenc' of bitumen. 0t is not

regarded as suitable for use in connection with the testing of road tarbecause of the high surface tension e6hibited b' these materials.

PR"$!%UR!:

(i) reparation of test specimen1 Soften the material to a pouring

consistenc' at a temperature not more than #* for tars and 9* for

bitumen abo"e the appro6imate softening point and stir it thoroughl' until it

is homogeneous and is free from air bubbles and water. our the melt intothe container to a depth at least

%mm in e6cess of the e6pected penetration. rotect the sample from dust

and allow it to cool in an atmosphere at a temperature between %5 to 3 *


11/24

for one hour. Then place it along with the transfer dish in the water bath at

5 ± .% *2 unless otherwise stated.

(ii) 8ill the transfer dish with water from the water bath to depth sufficient to

co"er the container completel'2 place the sample in it and put it upon the

stand of the penetration apparatus.

(iii) *lean the needle with benEene2 dr' it and load with the weight. The total

mo"ing load re7uired is % ± .5 gms2 including the weight of the needle2

carrier and super-imposed weights.

(i") d=ust the needle to ma+e contact with the surface of the sample. Thisma' be done b' placing the needlepoint in contact with its image reflected

b' the surface of the bituminous material.

(i) ?a+e the pointer of the dial to read Eero or note the initial dial reading.

(ii) ;elease the needle for e6actl' fi"e seconds.

("i) d=ust the penetration machine to measure the distance penetrated.

("ii)?a+e at least 3 readings at points on the surface of the sample not less

than % mm apart and not less than lmm from the side of the dish. fter

each test return the sample and transfer dish to the water bath and wash

the needle clean with benEene and dr' it. 0n case of material of penetration

greater than 52 three determinations on each of the two identical test

specimens using a separate needle for each determination should be made2

lea"ing the needle in the sample on completion of each determination toa"oid disturbance of the specimen.

PR!$AUTI"&S:


12/24

(i) There should be no mo"ement of the container while needle penetrates

into sample.

(ii) The sample should be free from an' e6traneous matter.

(iii)The needle should be cleaned with benEene and dried before penetration.

"'S!RATI"&S

ctual test temperature > *

enetration dial reading Test % Test Test 3

(a) 0nitial

(b) 8inal

enetration Balue

?ean

R!SUT:

?ean enetration Balue >


13/24

R!$"MM!&%!% AU!:

enetration test is a commonl' adopted test on bitumen to grade the

material in terms of its hardness. ,/% grade bitumen indicates that its

penetration "alue lies between , %.Frading of bitumen helps to assess

its suitabilit' in different climatic conditions and t'pes of construction. 8or

bituminous macadam and penetration macadam2 0;* suggests bitumen

grades 3/$2 #/&2 ,/%. 0n warmer regions2 lower penetration grades

are preferred to a"oid softening whereas higher penetration grades li+e

%,/ are used in colder regions to pre"ent the occurrence of e6cessi"e

brittleness. 4igh penetration grade is used in spra' application wor+s.


14/24

AIM:

(i) To measure the ductilit' of a gi"en sample of bitumen

(ii) To determine the suitabilit' of bitumen for its use in road construction.

APPARATUS:

The apparatus as per 0S1 %,-%9&, consists of

(i) !ri7uette mould1 0t is made of brass. *ircular holes are pro"ided at ends

called clips to grip the fi6ed and mo"able ends of the testing machine. The

mould when properl' assembled form a bri7uette specimen of following

dimensions.

Total length &5. ± .5 mm


15/24

@idth at minimum cross-section

(half wa' between clips) %. ± .%mm

Thic+ness throughout %. ± .%mm

(ii) @ater bath1 bath maintained within &. ±.% * of the specified test

temperature containing not less than % litres of water2 the specimen being

submerged to a depth of not less than % cms and supported on a

perforated shell and less than 5 cms from the bottom of the bath.

(iii) Testing machine 1 8or pulling the bri7uette of bituminous material apart2an' apparatus ma' be used which is so constructed that the specimen will

be continuousl' submerged in water while the two clips are being pulled

apart horiEontall' at a uniform speed of 5 ± .5 mm per minute.

(i") Thermometer. ;ange -$$* and readable up to .*

T!"R#:

The ductilit' test gi"es a measure of adhesi"e propert' of bitumen and its

abilit' to stretch. 0n fle6ible pa"ement design2 it is necessar' that binder

should form a thin ductile film around aggregates so that ph'sical

interloc+ing of the aggregates is impro"ed. !inder material ha"ing

insufficient ductilit' gets crac+ed when sub=ected to repeated traffic loads

and it pro"ides per"ious pa"ement surface.


16/24

(i) ?elt the bituminous test material completel' at a temperature of &5* to

% * abo"e the appro6imate softening point until it becomes thoroughl'

fluid.

(ii) Strain the fluid through 0S sie"e 3.

(iii) fter stirring the fluid2 pour it in the mould assembl' and place it on a

brass plate. 0n order to pre"ent the material under test from stic+ing2 coat

the surface of the plate and interior surfaces of the sides of the mould with

mercur' or b' a mi6ture of e7ual parts of gl'cerine and de6trine.

(i") fter about 3-$ minutes2 +eep the plate assembl' along with thesample in a

water bath. ?aintain the temperature of the water bath at & * for half an

hour.

(") ;emo"e the sample and mould assembl' from the water bath and trim

the specimen b' le"elling the surface using a hot +nife.

("i) ;eplace the mould assembl' in water bath for , to 9 minutes.

("ii) ;emo"e the sides of the mould.

("iii)4oo+ the clips carefull' on the machine without causing an' initial

strain.

(i6) d=ust the pointer to read Eero.

(6) Start the machine and pull clips horiEontall' at a speed of 5 mm per

minute.

(6i) ote the distance at which the bitumen thread of specimen brea+s.


17/24

?ean of two obser"ations rounded to nearest whole number is ductilit'

"alue.

Note: ?achine ma' ha"e a pro"ision to fi6 two or more moulds so as to test

three specimens simultaneousl'.

PR!$AUTI"&S:

(i) The plate assembl' upon which the mould is placed shall be perfectl' flat

and le"el so that the bottom surface of the mould touches it throughout.

(ii) 0n filling the mould2 care should be ta+en not to distort the bri7uette andto see that no air poc+et is within the moulded sample.

"'S!RATI"&S:

(i) !itumen Frade >

(ii) ouring Temperature >

(iii) Test Temperature >

(i") eriod of cooling in minutes

(a) 0n air >

(b) 0n water bath before trimming >

(c) 0n water bath after trimming >

% 3


18/24

(a) 0nitial ;eading

(b) 8inal ;eading

R!SUT:


19/24

LAB TESTS ON BITUMEN TO CHECKQUALITY

Various tests are conducted on bitumen to assess its consistency, gradation, viscosity, temperature

susceptibility, and safety.

There are a number of tests to assess the properties of bituminous materials. The following tests are

usually conducted to evaluate different properties of bituminous materials.

1. Penetration test

2. Ductility test

3. oftening point test

!. pecific gravity test

". Viscosity test

#. $lash and $ire point test

%. $loat test

&. 'ater content test

(. )oss on heating test

1.PENETRATION TEST

*t measures the hardness or softness of bitumen by measuring the depth in tenths of a millimeter to

which a standard loaded needle will penetrate vertically in " seconds. +* had standardied the

e-uipment and test procedure.

The penetrometer consists of a needle assembly with a total weight of 1g and a device for

releasing and loc/ing in any position. The bitumen is softened to a pouring consistency, stirred

thoroughly and poured into containers at a depth at least 1" mm in e0cess of the e0pected

penetration. The test should be conducted at a specified temperature of 2".

*t may be noted that penetration value is largely influenced by any inaccuracy with regards to

pouring temperature, sie of the needle, weight placed on the needle and the test temperature.


20/24

*n hot climates, a lower penetration grade is preferred. The $ig1 shows a schematic Penetration

Test setup.

Also Read: Penetraton Test Pro!ed"re o# Bt"$en

Fig-1 Penetration Test Setup

%.&UCTILITY TEST

Ductility is the property of bitumen that permits it to undergo great deformation or elongation.

Ductility is defined as the distance in cm, to which a standard sample or bri-uette of the material will

be elongated without brea/ing. Dimension of the bri-uette thus formed is e0actly 1 cm s-uare. The

bitumen sample is heated and poured in the mould assembly placed on a plate. These samples with

moulds are cooled in the air and then in water bath at 2% temperature. The e0cess bitumen is cut

and the surface is leveled using a hot /nife. Then the mould with assembly containing sample is /ept

in water bath of the ductility machine for about ( minutes. The sides of the moulds are removed,

the clips are hoo/ed on the machine and the machine is operated. The distance up to the point of

brea/ing of thread is the ductility value which is reported in cm.

The ductility value gets affected by factors such as pouring temperature, test temperature, rate of

pulling etc.

minimum ductility value of %" cm has been specified by the +*. $ig2 shows ductility Test

Process.

Also Read: &"!tlt' Test Pro!ed"re o# Bt"$en

http://civilblog.org/2013/05/12/penetration-value-of-bitumen-is1203-1978/http://civilblog.org/2013/05/12/ductility-value-of-bitumen-is1208-1978/http://civilblog.org/2013/05/12/ductility-value-of-bitumen-is1208-1978/http://civilblog.org/2013/05/12/penetration-value-of-bitumen-is1203-1978/


21/24

Fig-2 Ductility Test

(.SO)TENIN* POINT TEST

oftening point denotes the temperature at which the bitumen attains a particular degree of

softening under the specified condition of test.

The test is conducted by using 4ing and +all apparatus. brass ring containing test sample of

bitumen is suspended in li-uid li/e water or glycerin at a given temperature. steel ball is placed

upon the bitumen sample and the li-uid medium is heated at a rate of " per minute. Temperature

is noted when the softened bitumen touches the metal plate which is at a specified distance below.

5enerally, higher softening point indicates lower temperature susceptibility and is preferred in hot

climates. $ig3 shows oftening Point test setup.

Also Read: So#tenn+ Test Pro!ed"re o# Bt"$en

http://civilblog.org/2013/05/12/softening-point-of-bitumen-is12051978/http://civilblog.org/2013/05/12/softening-point-of-bitumen-is12051978/


22/24

Fig-3 Softening Point Test Setup

,.SPECI)IC *RA-ITY TEST

The specific gravity of bitumen is defined as the ratio of mass of given volume of bitumen of /nown

content to the mass of e-ual volume of water at 2%. The specific gravity can be measured using

either pycnometer or preparing a cube specimen of bitumen in semi solid or solid state.

*n paving 6obs, to classify a binder, density property is of great use. *n most cases bitumen is

weighed, but when used with aggregates, the bitumen is converted to volume using density values.

The density of bitumen is greatly influenced by its chemical composition. *ncrease in aromatic type

mineral impurities cause an increase in specific gravity.

The specific gravity of bitumen varies from .(% to 1.2.

Also Read: Se!#! *ra/t' Test Pro!ed"re o# Bt"$en

0.-ISCOSITY TEST

http://civilblog.org/2014/07/21/specific-gravity-test-on-bitumen/http://civilblog.org/2014/07/21/specific-gravity-test-on-bitumen/


23/24

Fig-4 Viscosity Test

Viscosity denotes the fluid property of bituminous material and it is a measure of resistance to flow.

t the application temperature, this characteristic greatly influences the strength of resulting paving

mi0es.

)ow or high viscosity during compaction or mi0ing has been observed to result in lower stability

values. t high viscosity, it resists the compactive effort and thereby resulting mi0 is heterogeneous,

hence low stability values. nd at low viscosity instead of providing a uniform film over aggregates, it

will lubricate the aggregate particles.

7rifice type viscometers are used to indirectly find the viscosity of li-uid binders li/e cutbac/s and

emulsions.

The viscosity e0pressed in seconds is the time ta/en by the " ml bitumen material to pass through

the orifice of a cup, under standard test conditions and specified temperature. Viscosity of a cutbac/can be measured with either !. mm orifice at 2" or 1 mm orifice at 2" or !.

Also Read: -s!ost' Test o# Bt"$en E$"lson ' Sa'olt )"rol -s!o$eter

2.)LASH AN& )IRE POINT TEST

t high temperatures depending upon the grades of bitumen materials leave out volatiles. nd these

volatiles catch fire which is very haardous and therefore it is essential to -ualify this temperature for

each bitumen grade. +* defined the ash point as the temperature at which the vapour of bitumen

momentarily catches fire in the form of ash under specified test conditions. The fire point is definedas the lowest temperature under specified test conditions at which the bituminous material gets

ignited and burns.

3.)LOAT TEST

http://civilblog.org/2015/05/16/viscosity-test-of-bitumen-emulsion-by-saybolt-furol-viscometr-is-3117-2004/http://civilblog.org/2015/05/16/viscosity-test-of-bitumen-emulsion-by-saybolt-furol-viscometr-is-3117-2004/


24/24

8ormally the consistency of bituminous material can be measured either by penetration test or

viscosity test. +ut for certain range of consistencies, these tests are not applicable and $loat test is

used.

The apparatus consists of an aluminum oat and a brass collar filled with bitumen to be tested. The

specimen in the mould is cooled to a temperature of " and screwed in to oat. The total test

assembly is floated in the water bath at " and the time re-uired for water to pass its way through

the specimen plug is noted in seconds and is e0pressed as the oat value.

4.5ATER CONTENT TEST

*t is desirable that the bitumen contains minimum water content to prevent foaming of the bitumen

when it is heated above the boiling point of water.

The water in bitumen is determined by mi0ing /nown weight of specimen in a pure petroleum

distillate free from water, heating and distilling of the water. The weight of the water condensed and

collected is e0pressed as percentage by weight of the original sample.

The allowable ma0imum water content should not be more than .29 by weight.

6.LOSS ON HEATIN* TEST

'hen the bitumen is heated it loses the volatility and gets hardened. bout "gm of the sample is

weighed and heated to a temperature of 1#3 for " hours in a specified oven designed for this test.

The sample specimen is weighed again after the heating period and loss in weight is e0pressed as

percentage by weight of the original sample.

+itumen used in pavement mi0es should not indicate more than 19 loss in weight, but for bitumen

having penetration values 1"2 up to 29 loss in weight is allowed.

green roads (exp).docx

Documents