Journal of Traffic and Transportation Engineering 7 (2019) 85-95 doi: 10.17265/2328-2142/2019.02.004

Effect of Sodium Chloride on Properties of Bitumen

Md. Shariful Islam

Department of Civil Engineering, RUET, Bangladesh

Abstract: Now-a-days a lot of modifications are taking place throughout the world to develop the existing highway materials to fulfill the demand of increased vehicles. People are at trend to innovate something new that can do better than it was. Some materials produce good effect and enhance the strength as well as qualities of bitumen. On the other hand, some materials are responsible for adverse effect on the bitumen. In saline areas like coastal regions, the salts play a significant role on the bituminous pavements. Sea water nearly contains 3% sodium chloride and evaporation of intake bodies of water has produced large and extensive deposits of it. We can be economically benefited if salt is used as an admixture to bitumen. But we do not even know the impact, good or bad of the mixing of salt with bitumen. The main objective of this paper to find out whether it is desirable or not taking various proportion salt with bitumen and doing specified test of bitumen. It is observed from the laboratory test that the penetration and ductility values are gradually increased with increased of salt content. The flash point, fire point and softening point value are stepwise reduced as percentage of salt content increased. Moreover it reduces the stability of roads. Mixing of salt to bitumen upgrades workability and it is beneficial in the economical point of view. Finally moisture effect test on the bituminous mix with the inclusion of salts show the degradation of strength due to moisture movement. Key words: Sodium chloride, bitumen, bituminous mix, flash fire point, stability.

1. Introduction

Bituminous mixes are most commonly used all over

the world in pavement construction. Under normal

circumstances, conventional bituminous materials if

designed and executed properly perform quite

satisfactory. But for special applications like

roundabouts or where the traffic is extremely heavy,

stiffer mixes are required which can have large fatigue

life and more resistance permanent deformation. Most

publications ascribe moisture damage to variables like

bitumen properties, aggregate characteristics, hot mix

processing, bituminous mixture characteristics, quality

control during construction, nature of water at the

interface, dynamic effect of traffic loading, type and

properties of anti stripping additives, and others. The

great diversity of variables and differences in earlier

research results reported make prediction of moisture

sensitivity difficult. Most mechanistic design methods

for bituminous pavements mainly base on fatigue and

Corresponding author: Md. Shariful Islam, B.Sc., research field: civil engineering.

rutting as the primary design criteria. However,

SHRP’s mechanistic/analytical approach to pavement

design proposed the need to consider resistance to

moisture damage as a key factor in selection and

proportioning of binders and aggregates [1-3].

In coastal area, pavement often comes across with

saline water. In this area, the salts particularly sodium

chloride plays an important role in the stability as well

as durability of roads. In this situation, the effect of

salts on properties of bitumen is important for proper

design and maintenance of the pavements. The present

status of literature, indicates that a little work has been

conducted to determine the behavioral changes in the

bituminous pavements in the present of salts. In this

paper, an attempt has been undertaken to study the

effect of salts on varies properties of bitumen.

2. Objective of Study

In recent years, a significant achievement has been

made in different fields of engineering. Also various

causes have been effectively determined to take

appropriate measures against the determination and

D DAVID PUBLISHING

Effect of Sodium Chloride on Properties of Bitumen

86

detrimental effect. In general, the presence alkalis and

salts produce harmful effect on the behavioral aspects

of binding materials. In this study, an attempt has

been made to quantify the adverse effects in term of

some specific standard tests. The objectives of this

study are:

To find the effect of salts on the properties of

bitumen;

To determine the variation of strength with the

inclusion of salts;

To observe the effect of water on the strength of

bituminous mixes with inclusion of salts in bitumen;

To carefully examine the use of salts in the

bitumen in terms of various properties such as

penetration, solubility, ductility etc.

3. Tested on Bitumen

To determine its behavior and its suitability a variety

of tests have been specified by institutions like ASTM,

I.S.I, Asphalt Institute, and B.S.I. The various tests of

bitumen are as follows:

(1) Penetration Test

Penetration value test on bitumen is a measure of

hardness or consistency of bituminous material.

Penetration value is the vertical distance traversed or

penetrated by the point of a standard needle into the

bituminous material under specific conditions of load,

time and temperature. This distance is measured in one

tenth of a millimeter.

(2) Softening Point Test

The softening point of bitumen or tar is the

temperature at which the substance attains particular

degree of softening. As per IS: 334-1982, ASTM

E28-67 or ASTM D36 or ASTM D6493-11, it is the

temperature in ºC at which a standard ball passes

through a sample of bitumen in a mould and falls

through a height of 2.5 cm, when heated under water or

glycerin at specified conditions of test.

(3) Flash and Fire Point Test

Flash and Fire point test is conducted on bitumen to

know the safe mixing and application temperature

values of particular bitumen grade.

The flash point of a material is the lowest

temperature in which vapor of substance quickly

catches fire in the form of flash under definite

conditions of the test. So, at this point fire will not last

longer, just a flash will appear for a fraction of second.

The fire point of a material is the lowest temperature

at which material catches fire and burns under definite

conditions of test. The presence of combustible

materials in a bituminous material can be indicated by

the fire point.

(4) Ductility Test

The flexible pavement construction where the

bitumen binders are used, is of significant importance

that binders from ductile thin film around the

aggregates. This serves as a satisfactory binder in

improving physical interlocking of the aggregates. The

binder material which does not possess sufficient

ductility would crack and thus provide previous

pavement surface. It has been started by some agencies

that the penetration and ductility properties go together,

but depending upon the chemical composition and the

type of crude source of the bitumen, sometimes it has

been observed that the above statement is incorrect. It

may hence be mentioned that the bitumen may satisfy

the penetration value, but may fail to satisfy the

ductility requirements. Bitumen paving engineer

would however want that both test requirements be

satisfied in field jobs. Penetration or ductility can not

in any case replace each other. The ductility is

expressed as the distance in centimeters to which a

standard briquette of bitumen can be stretched before

the thread cracks. The test is conducted at 27 ± 0.5 °C

and a rate of pull of 50 ± 2.5 mm per minute. The test

has been standardized by the ISI.

(5) Specific Gravity Test

The density of a bituminous binder is a fundamental

property frequently used as an aid in classifying the

binders used in paving jobs. In most applications, the

Fig. 1 Penet

Fig. 2 Soften

Fig. 3 Flash

tration test app

ning point test

h and fire point

Effect

paratus.

t apparatus.

t test.

of Sodium Chhloride on Prroperties of BBitumen

877

88

Fig. 4 Ducti

bitumen is

aggregate sy

volume bas

required for

specific grav

composition

aromatic typ

specific gr

standardized

4. Materia

(1) Bitum

(2) Sodium

4.1 Effect of

One of the

engineering,

came into ex

employed

occurrence

cohesive bon

is considere

failure in ter

Majidzade

adhesion fai

include the

techniques a

ility test.

weighted,

ystem, the bit

sis. Thus an

r conversion

vity is greatl

n of the bin

pe compound

ravity. The

d by the ISI.

als Used for

men

m chloride.

f Water on Bit

e complex pro

, existing sinc

xistence is str

by highwa

of adhesion

nds within th

d as great ec

rms of proper

eh stated th

ilure phenom

e material

and diversifi

Effect

but finally

tumen conten

n accurate d

n of weight

y influenced

nder. Increas

ds caused an

test proce

r Specimen

tuminous Mix

oblems in the

ce bitumen pa

ripping. The t

ay engineers

failure or w

he asphalt agg

conomic loss

r mixture desi

hat the facto

menon are inn

characteristic

ed environm

of Sodium Ch

y in use w

nt is converte

density value

to volume.

by the chem

sed amounts

n increase in

dure has b

n

xes

e field of high

aving technol

term stripping

s, denotes

weakening of

gregate system

and enginee

ign.

ors affecting

numerable. T

cs, construc

mental conditi

hloride on Pr

with

ed in

e is

The

mical

s of

n the

been

hway

logy

g, as

the

f the

m. It

ering

the

They

ction

ions.

The

por

owi

dive

mec

phe

the

(

A

fun

ther

pos

disp

bind

the

exh

of a

(

T

ther

film

from

coa

inte

deta

bec

min

roperties of B

ey are displac

e pressure th

ing to the com

ersity of en

chanism may

enomenon in

theories are b

1) Displacem

According to

ction in t

rmodynamica

sition [4-8]. It

place phenom

der aggregate

water phase.

hibit any bind

aggregate coa

2) Detachme

The theory

rmodynamic

m of water th

m within the

ating remains

erface are be

achment proc

comes intimat

neral surface.

Bitumen

cement, film

heories. Of c

mplexities of

nvironmental

y be adequate

bituminous m

briefly summ

ment Concept

o this theor

the presenc

ally unstable

t is generally

mena to be in

e interface sh

That is well,

der displacem

ating is destro

nt Concept

attributes

replacement

hat may com

e aggregate

intact [9-12].

elieved to b

cess. The wa

tely associate

m rupture, det

course it is

f material com

l conditions

e to explain

mixtures. The

marized as foll

ry the binde

ce of wate

and reacts to

y believed tha

nitiated in a

hould becom

coated aggre

ment unless th

oyed.

the adhe

of the bitum

me from eithe

while from

. The characte

be very impo

ater reaching

ed with the l

tachment and

obvious that

mposition and

, no single

the stripping

e concepts of

lows:

er aggregate

er becomes

o more stable

at, in order to

mixture, the

me exposed to

egate may not

he continuity

sion to a

men by a thin

er outside or

the bitumen

eristics of the

ortant in the

the interface

lattice of the

d

t

d

e

g

f

e

s

e

o

e

o

t

y

a

n

r

n

e

e

e

e

(3) Pore P

It has be

pressure in t

in stripping

of bituminou

also act and

forces. In a

water is pre

moving loa

contributing

four concep

theories can

stripping an

fact only con

4.2 Effect of

There ar

occurrence

mixtures: pr

application

bituminous

reduce the c

least one of th

of view, the w

by decreasing

In fact, this a

preventive m

paving us

bituminous a

Fig. 5 Exper

Pressure Conc

een postulate

the mixture o

phenomena [

us pavement a

d these greatl

saturated pa

essed into th

ad and suck

g to the stripp

pts, the dis

n be classifie

nd pore press

ntributing to t

f Mixture Den

re primarily

of stripping

resence of wa

and the ph

aggregate sy

chances of str

hese factors. F

water present

g the void con

approach cou

measures in th

sing the p

aggregate sys

rimental setup

Effect

cept

ed that the

f high void co

[13]. That is,

additional for

ly exceed the

avement unde

he pavement

ked out beh

ing phenome

splacement

ed as the pr

sure, film rup

the phenome

nsity on Stripp

three perq

g phenomena

ater in paveme

hysiochemica

stem. In orde

ripping, one s

From the pave

in the paveme

ntent of the bit

uld be conside

he constructio

physio-chem

stem.

p of compressiv

of Sodium Ch

buildup of p

ontent may re

on a wet sur

rces due to tra

e thermodyna

er dynamic l

t in front of

hind the w

ena. Among th

and detachm

rimary cause

pture concept

na.

ping

quisites for

a in bitumin

ent, repeated

al nature of

er to eliminat

should attemp

ement design p

ent can be redu

tuminous mixt

ered as one of

on of bitumin

mically unst

ve strength.

hloride on Pr

pore

esult

rface

affic

amic

load,

f the

wheel

hese

ment

es of

ts in

the

nous

load

the

te or

pt at

point

uced

tures.

f the

nous

table

4.3

Spe

T

coa

0.50

cub

C39

type

is u

test

surf

smo

test

curi

give

4.4

T

sho

of

IRG

and

170

ram

100

grad

grad

may

roperties of B

Preparatio

ecimen

The mix prop

arse aggregate

0. Test for c

be. American

9/C39M prov

es of specime

used. After 24

t specimens

face of these

ooth. These

ting machine

ing. Load at t

es the compre

Marshall Tes

The coarse ag

ould be propo

mineral agg

G.29-1968. A

d filler are ta

0 °C to 190

mmer, cleaned

0 °C to 145 °

de bitumen m

de bitumen 1

y be suitably

Bitumen

on of Com

portion of ce

e is 1:2:4. T

ompressive s

Society for

vides Standar

en each cube

4 hours these

are put in w

specimens s

specimens ar

after 3 days

the failure div

essive strengt

st Specimen

ggregates, fin

ortioned and m

gregates and

Approximately

aken and hea

°C. The com

d and kept pre

C. The mixin

may be aroun

60 °C. The w

alerted a thic

mpressive St

ement fine ag

The water cem

strength is ca

Testing Mate

rd Test. For

e 10 cm × 10

e moulds are

water for cur

should be ma

re tested by

7 days curin

vided by area

th of concrete

ne aggregates

mixed specifi

bitumen bi

y 1,200 g o

ated to a tem

mpaction mou

e-heated to te

ng temperatur

nd 154 °C th

weight of agg

ckness of 63.5

89

trength Test

ggregate and

ment ratio is

arried out on

erials ASTM

cube test the

cm × 10 cm

removed and

ing. The top

ade even and

compression

ng or 28 days

a of specimen

e.

s and mineral

fied gradation

inder as per

of aggregates

mperature of

uld assembly,

emperature of

re for 80/100

hat for 60/70

gregate taken

5 ± 3.0 mm.

9

t

d

s

n

M

e

m

d

p

d

n

s

n

l

n

r

s

f

,

f

0

0

n

Effect of Sodium Chloride on Properties of Bitumen

90

5. Results and Discussions

5.1 Effect of Salt on Properties of Bitumen

(a) (b)

Fig. 6 (a) variation of penetration value and (b) specific gravity with respect to salt content.

(c) (d)

Fig. 7 (c) variation of ductility and (d) softening value with respect to salt content.

(e) (f)

Fig. 8 (e) variation of flash point value and (f) fire point value with respect to salt content.

80

82

84

86

88

90

92

94

0 2 4 6

PEN

ETRATION VALU

E

SALT CONTENT %

1.01

1.015

1.02

1.025

1.03

1.035

0 2 4 6

specific gravity

salt content %

95

100

105

110

115

120

0 2 4 6

Ductility (cm

)

salt content %

40

42

44

46

48

50

52

54

0 2 4 6

soften

ing value 0c

salt content %

270

275

280

285

290

295

300

305

310

0 2 4 6

Flash point 

salt content

280

285

290

295

300

305

310

315

320

325

0 2 4 6

Fire point

salt content %

Effect of Sodium Chloride on Properties of Bitumen

91

(g)

Fig. 9 (g) variation of solubility with respect to salt content.

6. Conclusion

Sodium chloride has played a crucial role in

improvement of the different properties of the bitumen.

But sometimes it has adverse effects as reducing the

strength of the bituminous mixes. From the test results,

we conclude that the stability value of the bituminous

mixes decreases gradually with increase in salt content

in bitumen. On the basis of the test results and

subsequent discussions, it was concluded that the

penetration value and specific gravity increases and

softening point, flush & fire point, solubility and

ductility of bitumen decreases with increasing salt in

pure bitumen which indicated that the adhesion and

cohesion properties of bitumen were reduced with

increasing the percentage of salt in bitumen .From the

Marshall test regarding the consideration, the salt

tolerable limit varying from 0% to 5%.

Acknowledgments

Utmost gratitude to the Almighty ALLAH, without

his mercy and blessing, this work would not been

possible. I am grateful and would like to express

sincere gratitude to my respective teachers,

Department of Civil Engineering, Rashahi University

of Engineering & Technology, Rajshahi, for sharing

their vision and experience that enabled me to

successfully complete the work. I am also grateful to

my parents and my friends, without their

encouragement it is totally unable to complete this

work.

References

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[2] American Society for Testing and Materials (ASTM) D 2726, D 1074 D1075, C29 and C128. 1979.

[3] Afroz, S. S. K., and Prasad, K. S. B. 2012. “Utilization of Waste Plastic as a Strength Modifier in Surface Course of Flexible and Rigid Pavements.” Int J Eng Res Appl 2 (4): 1185-91.

[4] Button, J. W., and Little, D. N. 1988. “Additives Have Potential to Improve Pavement Life.” Scranton Gillette Communications, Roads and Bridges 26 (1): 76-80.

[5] Denning, J. H., and Carswell, J. 1981. Improvements in Rolled Asphalt Surfacing by Addition of Organic Polymers. Transport and Road Research Laboratory, United Kingdom.

[6] De Carteret, R. S., Buzzi, O., and Fityus, S. 2011. “A Review of the Effects of Salinity on Road Pavements and Bituminous Surfacings.” Unsaturated Soils: Theory and Practice: 803-8.

[7] Prusty, B., and Panda, M. 2012. “Use of Waste Polythene in Bituminous Concrete Mixes.” 108Ce036.

[8] Fromm, H. J., and Kennepohl, G. J. A. 1979. “Sulphur Asphaltic Concrete on Three Ontario Test Road.” In Proc. of 48th Int. Conference on Association of Asphalt Paving Technologists, 135-62.

[9] Martin, J. R., and Wallace, H. A. 1958. Design and Construction of Asphalt Pavements. New York: McGraw Hill Book co.

[10] Soni, K., and Punjabi, K. K. 2014. “Improving the Performance of Bituminous Concrete Mix by Waste Plastic.” Int. Journal of Engineering Research and Applications 3 (5): 863-8.

[11] Khanna, K. 1991. Highway Engineering (7th ed.). Delhi,

99.1

99.15

99.2

99.25

99.3

99.35

99.4

0 1 2 3 4 5 6

Solubility %

salt content %

Effect of Sodium Chloride on Properties of Bitumen

92

India: Standard Publishers Distributors. [12] Sangita, Tabrez Alam Khan, Sabin, R., and Sharma, D. K.

2010. “Effect of Waste Polymer Modifier on the Properties of Bituminous Concrete Mixes.” Construction and Building Materials 25 (10): 3841-8.

[13] Yamin, A., and Aschuri, I. 2017. “The Durability Study of The Use of Modified Waste Plastic-Bitumen in Asphalt Concrete Mix Containing Reclaimed Asphalt Pavement.” The Centre for Research and Development of Road and Bridge, Indonesia.

Fig. 10 R

Fig. 11 Vi

esult of saybol

iscosity of mix

100

110

120

130

140

150

160

170

0

Saybolt viscocities (sec)

138

140

142

144

146

148

150

152

154

156

158

160

0

Temperature (0c)

Effect

lt viscosities tes

xing and compa

1

1

of Sodium Ch

st of Bitumen.

action tempera

00

Temperatu

2 3

salt conte

viscosit

hloride on Pr

Appendi

ature with salt

200

ure (degree ce

4

ent %

ty vs salt c

roperties of B

ix

content in bin

300

el)

5 6

content

Bitumen

nder bituminou

400

)% s

1% 

2% 

3% 

4% 

5% 

mixing tempe

compaction T

us mix.

salt content

salt content

salt content

salt content

salt content

salt content

erature

Temperature

93

3

Effect of Sodium Chloride on Properties of Bitumen

94

Fig. 12 Variation of stability value with respect to bitumen content.

Fig. 13 Variation of flow value with respect to bitumen content percentage.

0

200

400

600

800

1000

1200

1400

0 1 2 3 4 5 6 7 8

stability (kg)

bitumen content %

pure bitumen

1% salt content

2% salt content

3% salt content

4% salt content

5% salt content

0

1

2

3

4

5

6

7

0 1 2 3 4 5 6 7 8

Flow value (m

m)

Bitumen content %

pure bitumen

1% salt content

2% salt content

3% salt content

4% salt content

5% salt content

Effect of Sodium Chloride on Properties of Bitumen

95

Fig. 14 Variation of percentage of total mix (Vv) with respect to bitumen content percentage.

Fig. 15 Variation of percentage void of mineral aggregate with respect to bitumen content.

0

2

4

6

8

10

12

0 1 2 3 4 5 6 7 8

air void in

 toatl m

ix (%Vv)

bitumen content %

pure bitumen

1% salt content

2% salt content

3% salt content

4% salt content

5% salt content

0

2

4

6

8

10

12

14

16

18

0 2 4 6 8

VMA (%)

bitumrn content %

pure bitumen

1% salt content

2% salt content

3% salt content

4% salt content

5% salt content