Page 1 of 6
European Journal of Business &
Social Sciences
Available at https://ejbss.org/
ISSN: 2235-767X
Volume 07 Issue 05
May 2019
Available online:https://ejbss.org/ P a g e | 1049
Cement Treated Marginal Aggregates for Roads
U. Arumuga Nainar, PG Student
Dept. of Civil Engineering
PRIST University
Thanjavur, India
Abstract—The primary objective of this project was
to develop a test for measuring the bond strength
between pavement layers. The research was also to
evaluate tack coat materials and application rates for
the Alabama Department of Transportation
(ALDOT). The project included a laboratory phase
and a field phase. For the laboratory work, the
experiment included two types of emulsion (CRS-2
and CSS-1) and a PG 64-22 asphalt binder that are
allowed by ALDOT’s specifications. Bond strengths
were measured with a shear type device at three
temperatures and three normal pressure levels.
Three application rates that encompassed the
specification range were investigated for each tack
coat. Laboratory prepared mixture samples included
a coarse-graded blend and a fine-graded blend to
represent two different surface textures. The effects
of tack coat type, application rate, mixture type,
testing temperature and normal pressure on the bond
strength were evaluated.
In the laboratory phase, it was found that all of the
main factors used in the test plan affected bond
strength. Testing temperature had the most
significant impact on bond strength. As the
temperature increases, bond strength decreases
significantly. The influences of tack coat type and
application rate on bond strength are different for
the fine-graded and coarse-graded mixtures.
Based on the laboratory work, a draft procedure
was developed for determining the bond strength
between pavement layers. An easy to use procedure
was selected that was believed to provide a good
indication of the quality of the bond. The procedure
utilizes the simple shear device developed by NCAT
which is similar to bond strength devices used in
several European countries. The draft procedure is
based on a test temperature of 77oF and a loading
rate of two inches/minute.
Index Terms — ALDOT; NCAT; PG 64-22 asphalt
binder;
I. INTRODUCTION
Quality road aggregates have become scarce and
costly in many places in India due to liberalization of the
economy and the consequent sudden increase in road
construction activities required for the development of
new infrastructure facilities. Low-volume roads, unlike
major highways, do not attract large funding because of
the small direct return from the investment, even though
they are very important for providing connectivity to the
centers of agricultural production in the countryside. It is
therefore necessary to keep road construction cost as low
as possible. The use of low-grade aggregates, which are
otherwise considered unsuitable for road construction,
appears to be an attractive proposition because of their
low cost, environmental considerations, and depleting
source of quality aggregates, if good performance can be
ensured through appropriate technology.
A major problem with low-grade aggregates is that
they undergo crushing during the rolling operation. This
problem can be overcome by suitably proportioning the
aggregate, sand, and cement and by compacting the mix
by a vibratory compactor at an appropriate water- tocement (w/c) ratio (by weight). No specific guidelines
are available in India for the design of lean cement
concrete using poor-quality aggregates (Tentative‘‘ 1976,
1979; ISI 1983). This paper describes laboratory
investigations for the evaluation of structural properties
of cement-treated low-grade aggregates. An example of
pavement design is also presented.
Page 2 of 6
European Journal of Business &
Social Sciences
Available at https://ejbss.org/
ISSN: 2235-767X
Volume 07 Issue 05
May 2019
Available online:https://ejbss.org/ P a g e | 1050
Low-grade laterite and pit-run gravel aggregates
available in abundance in eastern India may be turned
into a cost-effective base for low-volume roads when
ordinary portland cement, river sand, and aggregates are
mixed in a 1:6:12 proportion by weight. 152 × 152 × 152
mm3 cubes were cast at several water-cement ratios and
the mix was compacted by a vibratory plate compactor.
The compressive strength test was determined for
different water-cement ratios, and the one that gave the
maximum strength was used to prepare 102 × 102 × 508
mm3 beam specimens. A number of cubes and beams
were kept inside airtight polyethylene bags for
accelerated curing at a temperature of 50°C. Modulus of
rupture and flexural fatigue tests were carried for the
evaluation of pavement design parameters. A
methodology of design of a lightly cemented pavement
along with an example are also presented.
II. MATERIALS
Three types of aggregates, namely: (1) laterite
aggregate; (2) pit-run gravel; and (3) dolerite stone were
considered (Majumder 1992) in the present investigation.
A locally available material—laterite aggregates—are
homogeneous, vesicular, clinkerlike materials found in
hilly tropical countries that are structurally hydrated
ferric oxide (red color) and the vesicular infiltrate is
aluminum oxide (yellow color). It may also contain a
large amount of quartz and kaolinite (Gidigasu 1976).
Gravel aggregates are essentially quartzite and were
obtained from a pit at Dalbhumgarh, a location situated
90 km Northeast of Kharagpur, in India. Good-quality
dolerite aggregates, locally known as ̳ ̳chandil‘‘ stone
chips, were used for the third series of investigations for
comparison with the laterite and gravel aggregates.
Laterite and gravel aggregates passing through a 25-mm
sieve and retained in a 2.36-mm sieve were used in their
natural form after being washed. Sand obtained from the
bed of the
Kasai river located close to Kharagpur was also
washed before being used. Ordinary portland slag
cement. (OPSC) was used, which in proportion to
granulated blast furnace slag (a by-product of the steel
industry), is ;25%. According to the Bureau of Indian
standards (Indian 1989), the specification of OPSC is
similar to ordinary portland cement (OPC) with regard to
fineness, soundness, setting time, and compressive
strength at 3, 7, and 28 days. Oxide and sulfur as SO3 in
OPSC are limited to 8.0% and 3.0%, respectively.
The gradation of the three aggregates and sand are
presented in Fig. 1. Physical properties of the aggregates
and OPSC are given in Tables 1 and 2, respectively. It
can be seen that the Los Angeles abrasion values of the
weak aggregates are 55.4% and 46.4%, respectively, and
hence, they cannot be used in the bases of pavement
according to the specification of the Ministry of Surface
Transport (Specifications 1995), Government of India.
Water was tested for the presence of different
constituents and the results.
A.Literature Review
Material specification and construction practices for
airport overlays have not changed substantially since
their development in the 1960s. However, in the 1970s,
significant slippage failures occurred on airports in
Australia, primarily in the heavy braking zones. This
prompted the development of a policy on how to manage
and repair surface slippage failures, which included de- bonding and delamination (DoC 1978). To minimise
slippage risks, current practice is for airport interfaces
between asphalt overlays to incorporate:
Fig. 1. Aggregate Gradations
Fig. 2. Texturing the existing surface and removing the aged
and contaminated asphalt by cold milling.
Page 3 of 6
European Journal of Business &
Social Sciences
Available at https://ejbss.org/
ISSN: 2235-767X
Volume 07 Issue 05
May 2019
Available online:https://ejbss.org/ P a g e | 1051
Minimizing the milling water to reduce the generation
of slurry on the exposed surface.
Thorough cleaning and drying of the milled surface
by booming, vacuuming and blowing.
Complete coverage of the exposed surface with 0.15
to 0.20 l/m2 of bitumen emulsion tack coat.
Minimisation of trafficking on the tack coated surface
to reduce pick-up of tack coat by tyres.
This practice has generally resulted in good interface
bond with only very few reported surface failures
attributed to delamination. Despite their availability, only
minor additional cost and overwhelming evidence from
the USA to demonstrate their contribution to higher
overlay bond strength, premium tack coats, often referred
to as Trackless Tacks, have not been adopted.
III. EXPERIMENTAL INVESTIGATION
A.Mix Composition
An adequate quantity of sand should be used in the
mix so that it would act as a cushion between the soft
aggregates to minimize crushing of the aggregates during
rolling and traffic operations. Cement is a costly material
and the proportion of cement, sand, and aggregate was
taken as 1:6:12 by weight from an economic
consideration. Although there was no prior experience
concerning such mixes, it is obvious that the water
requirement will be rather large because of greater
quantities of sand and coarse aggregates in the mix.
For a given proportion of cement, coarse aggregate,
and sand, the w/c, ratio consistent with workability,
determines the strength of a normal cement concrete mix.
Strength rather than the density or the void content was
selected as the criterion for the evaluation of the
appropriate w/c ratio for the current mix proportion,
because the thickness of the pavement is dependent on it.
Several trial mixes were made with the w/c ratio ranging
from 0.5 to 1.8.
Oven-dried aggregates and sand were mixed with
cement in a mixing bowl with an appropriate quantity of
water. It was found that the mixes with a w/c ratio <1.0
were too dry for casting specimens. The compaction was
done by a plate vibrator having a static weight of 250 N
vibrating at a frequency of 3,000 rpm. The mix was
placed in 152 3 152 3 152 mm3 cubical molds and
prismatic molds that were 102 3 102 3 508 mm3.
The sides of the molds were removed after 24 h and
the specimens were immersed in water for curing, a
method closer to the curing of cement concrete roads
practiced in India. A few samples secured inside airtight
polyethylene bags were cured in an oven at 507C for
accelerated curing to determine the strength gain
characteristics when cured at a higher temperature.
B.Compressive Strength Test
A compressive load at a rate of 6 ton/min (Indian‘‘
1963a,b) was applied to the cubical specimens having
different w/c ratios. They were tested after 7, 14, 21, and
28 days of water curing and 3, 5, and 7 days for over
curing. The variation of compressive strength versus the
number of days of curing are plotted in Figs. 2(a), 3(a),
and 4(a), and the variation of compressive strength versus
w/c ratios are shown
The w/c ratios for maximum strength were found as
1.5, 1.2, and 1.3 for laterite, gravel, and dolerite
aggregates, respectively. The mix with laterite aggregates
requires higher w/c ratios because the aggregates are
vesicular and absorb more moisture. The percentages of
water content by weight of cement-sand-aggregate are
7.89, 6.31, and 6.84, respectively, for laterite, gravel, and
dolerite aggregates, which are lower than those in normal
cement concrete mixes. Figs. 2(a), 3(a), and 4(a) give the
comparative results of accelerated curing and water
curing for the cubical specimens.
Fig. 3. Compressive Strength of Laterite Aggregate Mix: (a) Curing Time
versus Compressive Strength; (b) w/c Ratio versus Compressive Strength
Slope is a measure of the fatigue response of the
material, where the greater the slope is, the faster is the
rate of damage. Slopes of the fatigue lines as evident
from
