FUOYE Journal of Engineering and Technology (FUOYEJET), Vol. 5, Issue 2, September 2020
ISSN: 2579-0625 (Online), 2579-0617 (Paper)
Suitability Assessment of Selected Lateritic Soils for
Highway Construction in Anambra State, Nigeria
Charles M.O. Nwaiwu, Ibeawuchi S. Chidera, and *Franklin. C. Uzodinma
Department of Civil Engineering, Nnamdi Azikiwe University, Awka, Nigeria
{cmo.nwaiwu|fc.uzodinma}@unizik.edu.ng
Received: 15-MAR-2020; Reviewed: 18-APR-2020; Accepted: 01-AUG-2020
http://dx.doi.org/10.46792/fuoyejet.v5i2.495
Abstract- Fifteen samples of coarse-grained lateritic soils obtained from different parts of Anambra State were assessed for their suitability
as materials for highway construction. The soil samples were subjected to laboratory tests to obtain their index properties, compaction and
California bearing ratio (CBR) characteristics. Three compactive efforts namely, British Standard Light (BSL) compaction, West African
Standard (WAS) and British Standard Heavy (BSH) compaction were employed in the compaction tests. Samples were soaked for 48hrs prior
to CBR testing. The index properties of the soils were used to classify the soils as silty sand (SM) or silty sand/clayey sand (SM-SC) based
on the Unified Soil Classification System (USCS) classification as well as silty soils (A – 4) or silty/clayey gravel and Sand (A – 2 -4) based
on American Association of State Highway and Transportation Officials (AASHTO) classification. All the fifteen soils fell under “grading F”
based on AASHTO standard specification designations for particle size distribution. The maximum dry unit weight (MDUW) of the soil samples
ranged from 16.203 kN/m3 to 19.424 kN/m3,17.385 kN/m3 to 19.996 kN/m3 and from 18.126 kN/m3 to 21.473 kN/m3 with corresponding
optimum moisture content of 11.4% to 21.4%, 12.45% to 12.5% and 8.5% to 11.75% for BSL, WAS and BSH respectively. The CBR values
ranged between 7.92% and 18.87%. Most of the soil (more than 50%) did not meet the lower values of MDUW while only 20% of the soils
had CBR values above 10% which is specified for subgrade soils by the AASHTO standard and the Nigerian Highway Design Manual, Federal
Ministry of works and Housing.
Keywords- coarse-grained, lateritic soils, highway pavement materials, USCS, AASHTO
—————————— ◆ ——————————
1 INTRODUCTION
L
ateritic soils can be described as reddish-brown
residual soils that are formed by the weathering of
pre-existing rocks such as granite, shale, limestone,
schist sandstone and gneiss (Okeke et al., 2013). They are
mainly formed in tropical climatic regions of the world
(Adeyemi, 2002). The geotechnical features/ behaviour
and performance of most lateritic soils are influenced by
some factors including origin, degree of weathering,
morphological characteristics, chemical and mineral
composition as well as by the environmental conditions.
Available data on geotechnical characteristics of laterite
soils show that they range in performance from very good
to poor for engineering purposes. (Eze et al, 2014)
A substantial increase in soil use for engineering works is
expected with any country gearing towards improved
infrastructural development and due to the abundance of
lateritic soils in tropical areas, these soils are utilized in
various forms of engineering works. The relationship
between all engineering infrastructure and their
foundation soils is of great importance for designers,
engineers and contractors. Lateritic soils are utilized as
construction materials in a range of civil engineering
works as. As road construction material and in view of
certain strength requirements, they form the sub-grade of
most roads in tropical areas, and can also be used as sub
base courses for roads not subjected to heavy traffic.
However, the use of unsuitable soil type in road
construction results in instability and subsequent failure.
Most road failures in some tropical areas are attributed to
poor construction materials (Adams and Adetoro, 2014).
*Corresponding Author
Standard, condition, and durability of the road network
in country play a significant role in the development of
the country as the major means of transportation of any
country is by road. Sufficient and reliable information on
the geotechnical properties of laterite such as strength,
grading, Atterberg limits, compaction properties and the
bearing ratio are important in order to make a convenient
choice for this basic material in construction engineering.
(Younoussa et al, 2008).
In tropical areas, especially because of the variance in
geotechnical properties of lateritic soils caused by
different formation factors, it is common to find
difference in the characteristics and investigation results
even within short distances and/or depth (Adeyemi and
Wahab, 2008). Thus, the need for investigating the
engineering properties of lateritic soils before their use in
civil engineering works is important to determine their
suitability as a construction material for that particular
need. Hence, the objective of this study is to assess the
suitability of selected coarse-grained lateritic soils in
Anambra State, Nigeria for highway construction, hence
providing data for engineers, designers and contractors
when they encounter such soils.
2 MATERIALS AND METHODS
Fifteen soil samples labeled STAN 1 – STAN 15 were used
in this study. The soils were obtained from different
locations within Awka, Anambra State, Nigeria.
(06°12'25" N 07°04'04" E) see map of study area in
appendix. These soils belong to the group of ferriginous
tropical soils derived from acid igneous and metamorphic
rocks (Osinubi, 1998a). The reddish-brown coloured
lateritic soils used in this study are low-plasticity clays
according to the Unified Soil Classification System, USCS
(ASTM D 2487). The coordinates of sampling locations are
shown in Table 1.
© 2020 The Author(s). Published by Faculty of Engineering, Federal University Oye-Ekiti.
208
This is an open access article under the CC BY NC license. (https://creativecommons.org/licenses/by-nc/4.0/)
http://dx.doi.org/10.46792/fuoyejet.v5i2.495
engineering.fuoye.edu.ng/journal
FUOYE Journal of Engineering and Technology (FUOYEJET), Vol. 5, Issue 2, September 2020
S/N
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Table 1. Coordinates of sampling locations
Samples
Longitude
Latitude
STAN 1
07°14'02" E
06°32'09" N
STAN 2
07°19'20" E
06°02'34" N
STAN 3
07°12'25" E
06°79'39" N
STAN 4
07°11'58" E
06°55'76" N
STAN 5
07°32'63" E
06°19'09" N
STAN 6
07°18'33" E
06°14'04" N
STAN 7
07°55'12" E
06°53'98" N
STAN 8
07°40'24" E
06°72'19" N
STAN 9
07°34'27" E
06°65'04" N
STAN 10
07°29'06" E
06°80'12" N
STAN 11
07°44'74" E
06°52'55" N
STAN 12
07°38'02" E
06°46'11" N
STAN 13
07°33'82" E
06°31'88" N
STAN 14
07°67'01" E
06°24'53" N
STAN 15
07°60'27" E
06°12'09" N
The samples were subjected to moisture content tests,
specific gravity test, sieve analysis test (hydrometer
method), Atterberg limit test, compaction test, and
California Bearing Ratio (CBR) test in the laboratory.
Sieve analysis and Atterberg limit tests were carried out
in accordance to BS 1377-2:1990. The compaction tests
were carried out with three different compaction energies
of BS Light compaction energy (BSL), BS Heavy
compaction energy (BSH), and West African Standard
(WAS) compaction energy. The BSH and BSL are the
British Standard (BS) equivalents of the Modified and
Standard Proctor compactions (ASTM D 1557 and ASTM
D 698), respectively. The WAS or Intermediate
compaction is the conventional energy level commonly
used in the region and consists of the energy derived from
a 4.5-kg rammer falling through 45.72 cm unto five layers
in a BS 1,000 cm3 capacity mould, each receiving 10 blows
(Ola 1983; Osinubi 1998a, b). CBR test was carried out
according to the procedure described in ASTM D1883-16
(ASTM D1883-16, 2016).
3 RESULTS AND DISCUSSIONS
3.1 PHYSICAL PROPERTIES
The physical properties of the soils used in this study and
a descriptive analysis of the range of index properties is
shown in Tables 2a and 2b, respectively. Index properties
of these soils can be used to classify based on AASHTO
(American Association of State Highway and
Transportation Officials) and USCS (United soil
classification system) as shown in Table 3. From Table 3,
it is seen that the all the lateritic soils considered are not
suitable for sub base.
ISSN: 2579-0625 (Online), 2579-0617 (Paper)
Table 2a. Index properties of the lateritic soils
Sample
STAN 1
STAN 2
STAN 3
STAN 4
STAN 5
STAN 6
STAN 7
STAN 8
STAN 9
STAN 10
STAN 11
STAN 12
STAN 13
STAN 14
STAN 15
Depth
of
sampli
ng
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
Specifi
c
gravity
, Gs
2.55
2.64
2.6
2.51
2.59
2.45
2.64
2.63
2.59
2.48
2.6
2.45
2.64
2.58
2.48
%
Fines
LL
(%)
PL (%)
PI (%)
36.13
36.67
33.34
32.4
36.96
34.97
32.64
38.13
30.42
29.52
37.71
28.91
27.24
27.12
37.5
28.3
26
29
30
28.3
28.1
28.5
30.8
28.5
28
30.4
27
27.6
27.8
29
26.69
23.89
25.41
25.33
24.80
26.69
25.41
25.88
25.86
24.62
26.02
24.89
25.01
24.24
22.47
1.61
3.12
5.59
4.67
3.50
1.41
3.09
4.92
2.64
3.38
4.38
2.11
2.59
3.56
6.54
Table 2b: Descriptive analysis of the range of index
properties
Descripti
on
Mean
Standard
Error
Standard
Deviation
Sample
Variance
Moist
ure
conten
t (%)
11.613
33
0.6195
13
2.3993
65
5.7569
52
Specif
ic
gravit
y, Gs
LL
(%)
PL
(%)
PI
(%)
33.310
67
1.0094
4
3.9095
46
15.284
55
28.486
67
0.3232
08
1.2517
8
1.5669
52
25.147
83
0.2833
89
1.0975
61
1.2046
4
3.5388
33
0.3747
74
1.4514
93
2.1068
33
2.562
%
Fines
0.0181
32
0.0702
24
0.0049
31
Table 3. Classification of the lateritic soils according to
USCS and AASHTO
STAN 1
STAN 2
USCS
classifica
tion
system
USCS
Group
symbol
SM
SM
STAN 3
SM-SC
A-2-4
Fair - good
STAN 4
SM-SC
A-2-4
Fair - good
STAN 5
SM
A-4
fair
STAN 6
SM
A-2-4
fair
STAN 7
SM
A-2-4
fair
STAN 8
SM-SC
A-4
Fair - good
STAN 9
SM
A-2-4
fair
STAN 10
SM
A-2-4
fair
STAN 11
SM-SC
A-4
Fair - good
STAN 12
SM
A-2-4
fair
STAN 13
SM
A-2-4
fair
STAN 14
SM
A-2-4
fair
STAN 15
SM-SC
A-4
Fair - good
Sample
designation
AASHTO
classificatio
n system
Suitability as
construction
material
USCS
AASHTO
group
symbol
A-4
A-4
fair
fair
General rating
as sub-grade
(AASHTO)
Fair - poor
Fair - poor
Excellent good
Excellent good
Fair - poor
Excellent good
Excellent good
Fair - poor
Excellent good
Excellent good
Fair - poor
Excellent good
Excellent good
Excellent good
Fair- poor
SM - Silty sand, SM-SC - Silty sand-Clayey sand, A-4 - Silty soils and A2-4 - Silty or clayey gravel and Sand
© 2020 The Author(s). Published by Faculty of Engineering, Federal University Oye-Ekiti.
209
This is an open access article under the CC BY NC license. (https://creativecommons.org/licenses/by-nc/4.0/)
http://dx.doi.org/10.46792/fuoyejet.v5i2.495
engineering.fuoye.edu.ng/journal
FUOYE Journal of Engineering and Technology (FUOYEJET), Vol. 5, Issue 2, September 2020
3.2 PARTICLE GRADATION
Particle gradation of each lateritic soil sample used in this
study is shown in Fig 1.
Table 4. AASHTO Standard Specification Designation M
147 (from AASHTO M 145-91) (2011)
%age (%) by mass passing square mesh sieve
Gradin
Gradin Gradin
Gradi Gradi Gradi
gA
gB
gC
ng D
ng E
ng F
100
100
75-95
100
100
100
100
6030-65
40-75
50-85
100
50557025-55
30-60
35-65
85
100
100
405515-40
20-45
25-50
70
100
2520308-20
15-30
15-30
45
50
70
2-8
5-20
5-15
5-20
6-20
8-25
sieve
STAN 1
STAN 4
STAN 7
STAN 10
STAN 13
STAN 2
STAN 5
STAN 8
STAN 11
STAN 14
STAN 3
STAN 6
STAN 9
STAN 12
STAN 15
50
25
9.5
4.75
100
2.0
90
0.425
0.075
Percentage passing (%)
80
Table 5. Compaction data for the lateritic soils
70
BSL
Samp
le
60
50
40
30
20
10
0.01
ISSN: 2579-0625 (Online), 2579-0617 (Paper)
Sieve
0.1 sizes (mm)
1
Fig. 1: Particle gradation curve for the lateritic samples
Most of the engineering properties of coarse-grained soils
are closely associated with the predominant particle size
(Gidigasu, 1976). The percentage of fines has significant
effect on the performance of the base and sub-base
materials (Garg 2009). The lateritic soils used in this study
can be classified under “grading F” based on the
AASHTO standard specification designation as shown in
Table 4. However the requirement for soils to be used as
sub-base include that the plasticity index shall be in the
range 4 to 9, the grading shall be C, D, E or F and a
minimum of 8% shall pass the 0.075 mm sieve and if it is
to be used as base course, the aggregate shall meet the
grading for B, C or D of AASHTO standard Specification.
The fraction passing the 0.075 mm sieve shall be not more
than one thirds of the fraction passing the 0.425 mm sieve
and plasticity index of not more than 6. Although these
soils satisfied the requirements for use as sub – base, the
minimum of fines do not. Hence these soils do not satisfy
the criteria for sub – base and base – course based on
particle size distribution.
3.3 COMPACTION CHARACTERISTICS
Results of the compaction test are shown in Table 5, from
the compaction results, it is observed that he maximum
dry unit weight (MDUW) of the soil samples ranged from
16.2033 kN/m3 to 19.4242 kN/m3,18.1255 kN/m3 to 21.473
kN/m3 and 17.3853 kN/m3 to 19.9955 kN/m3 with
corresponding optimum moisture content of 21.4% to
11.4%, 8.5% to 11.75%, and 12.45% to 12.5% for BSL, BSH
and WAS compaction efforts respectively.
STA
N1
STA
N2
STA
N3
STA
N4
STA
N5
STA
N6
STA
N7
STA
N8
STA
N9
STA
N 10
STA
N 11
STA
N 12
STA
N 13
STA
N 14
STA
N 15
BSL
MDU
O
W
MC
(Kg/m
(%)
3)
20.586
10.4
5
20.586
12
5
20.438
9.75
8
O
MC
(%)
OM
C (%)
14.8
14.8
15.7
15.7
13.0
13.0
14
14
11.8
11.4
11.4
14.2
14.2
BSH
OM
C
(%)
MDU
(kN/m3)
14.8
18.7544
15.7
17.8285
13.0
16.745
20.291
14
17.927
9.5
20.704
7
11.4
19.424
11.7
5
21.473
14.2
18.419
13.2
18.912
16.6
17.0898
13.8
18.2028
20.419
1
19.394
7
20.369
8
13.2
13.2
10.4
16.6
16.6
13
13.8
13.8
10.5
15.8
15.8
13
19.897
15.8
17.73
14.5
14.5
12
20.034
9
14.5
18.4195
21.4
21.4
19
18.321
21.4
16.2033
14.4
14.4
10.5
14.4
16.6958
11.0
11.0
8.5
11.0
17.1883
13.0
13.0
10.5
13.0
16.8928
18.025
5
18.125
5
18.518
Typical
MDUW
(kN/m3)
according
to USCS
18.912 –
21.276
18.912 –
21.276
15.76 –
21.276
15.76 –
21.276
18.912 –
21.276
18.912 –
21.276
18.912 –
21.276
15.76 –
21.276
18.912 –
21.276
18.912 –
21.276
15.76 –
21.276
18.912 –
21.276
18.912 –
21.276
18.912 –
21.276
15.76 –
21.276
3.4 CBR CHARACTERISTICS
The CBR values are shown in Table 6. Comparisons have
been made between experimental values and values from
standard tables extracted from Yoder and Witczak (1975)
for USCS and AASHTO classifications. Values of CBR
ranged between 7.92% and 18.87%. About 80% of the
samples had CBR values less than 10%. The plot of CBR
values against fines content to sand content ratio (FC/SC)
shown in fig 2a tends to suggest that CBR values
decreased as FC/SC values increased. This is in agreement
with the findings of Sreedhar and Fatima (2017) who
showed that soaked CBR values decreased consistently
with increase in fines content. Increase in fines content
© 2020 The Author(s). Published by Faculty of Engineering, Federal University Oye-Ekiti.
210
This is an open access article under the CC BY NC license. (https://creativecommons.org/licenses/by-nc/4.0/)
http://dx.doi.org/10.46792/fuoyejet.v5i2.495
engineering.fuoye.edu.ng/journal
FUOYE Journal of Engineering and Technology (FUOYEJET), Vol. 5, Issue 2, September 2020
corresponds with decrease in sand content and hence
increase in FC/SC ratios. Inan et al (2016) also showed that
CBR values decreased as fines contents increased.
Fig. 2a: A graph of CBR against fines content to sand content ratio
ISSN: 2579-0625 (Online), 2579-0617 (Paper)
Results obtained indicate that only STAN 10, STAN 11
and STAN 13 with CBR values of 11.96, 10.27 and 18.87
fall within the typical range of CBR according to
AASHTO and USCS. This shortfall could as a result of the
48hrs of soaking which reduces the CBR as compared to
the un-soaked typical range of CBR according to
AASHTO and USCS. However, only STAN 10, STAN 11
and STAN 13 with CBR values of 11.96, 10.27 and 18.87
respectively fall within the range of 10% to 25% CBR
value specified for sub grade soils by the AASHTO
standard and the Nigerian Highway Design Manual,
Federal Ministry of Works and Housing. All soil samples
tested are unsuitable for use as sub-base and base material
in road pavement construction since the CBR values are
less than 30% and 80% respectively as recommended by
the Nigerian Highway Design Manual, Federal Ministry
of Works and Housing (1997).
4 CONCLUSION
Fig. 2b: A graph of CBR against fines content to sand content ratio
The variation of soaked CBR with MDUW based on BSL
compaction energy showed two trends as shown in figure
2b. Values of CBR higher than 10% showed a consistent
decreasing trend as MDUW values increased. Soils with
CBR values less than 10% also showed decreasing trend
as MDUW increased.
Table 6. Comparison of CBR values with typical CBR
values according to AASHTO and USCS.
Sample
USCS
Group
symbo
l
STAN 1
STAN 2
STAN 3
STAN 4
STAN 5
STAN 6
STAN 7
STAN 8
STAN 9
STAN 10
STAN 11
STAN 12
STAN 13
STAN 14
STAN 15
SM
SM
SM-SC
SM-SC
SM
SM
SM
SM-SC
SM
SM
SM-SC
SM
SM
SM
SM-SC
AASH
TO
group
symbo
l
A-4
A-4
A-2-4
A-2-4
A-4
A-2-4
A-2-4
A-4
A-2-4
A-2-4
A-4
A-2-4
A-2-4
A-2-4
A-4
Typical
CBR
range
(USCS)
20 - 40
20 - 40
10 - 20
10 - 20
20 - 40
20 - 40
20 - 40
10 - 20
20 - 40
20 - 40
10 - 20
20 - 40
20 - 40
20 - 40
10 - 20
Typical
CBR
range
(AASHT
O)
10 - 20
10 - 20
20 - 40
20 - 40
10 - 20
20 - 40
20 - 40
10 - 20
20 - 40
20 - 40
10 - 20
20 - 40
20 - 40
20 - 40
10 - 20
CBR
valu
e (%)
8.27
8.56
8.96
8.69
8.76
8.48
7.92
7.96
8.43
11.96
10.27
9.3
18.87
8.48
7.92
Fifteen samples of coarse-grained lateritic soils are
subjected to basic laboratory tests in order to assess their
suitability as highway construction materials. MDUW
values obtained from BSL compaction did not meet the
lower limits of typical MDUW values indicated by USCS
for some lateritic soils. Soaked CBR values were higher
for soils with lower fines content/sand content ratios.
Soaked CBR values were higher for soils with lower fines
content/ sand content ratios. The soaked CBR values can
be used to determine lateritic soils that are suitable for
different pavement layers, while considering the
influence of fines contents characterized by fines
content/sand content ratios. Measured values of MDUW
may not be adequate for determining the suitability of
lateritic soils for pavement construction.
REFERENCES
Adams J.O. and Adetoro A. E. (2014) Analysis of Road Pavement
Failure caused by soil properties along Ado-Ekiti - Akure Road.
Nigeria International Journal of Novel Research in Engineering and
Applied Sciences (IJNREAS) vol.1 No. 1, pp 1-7.
Adeyemi, O.A. (2002) Geotechnical Properties of Lateritic Soil
Development over Quartz Schist in Ishara Area Southwestern
Nigeria. Journal of Mining and Geology. Vol. 38 No 1, pp 57 – 63.
Adeyemi, G.O. and K.A. Wahab, (2008). Variability in the
Geotechnical Properties of a Lateritic Soil from South Western
Nigeria. Bulletin of Engineering Geology and Environment. Vol. 67,
pp 579-584.
American Association of State Highway and Transport Officials
(AASHTO), (2011). AASHTO M147‐65. Materials for aggregate
and Soil Aggregate subbase, base, and surface courses. In
Standard Specifications for Transportation materials and methods of
sampling and Testing.
ASTM Designation D1883, (2007). “Standard Test Method for CBR
(California Bearing Ratio) of Laboratory Compacted Soils, pp 23. D1883-16:2016.
ASTM (1993): D 2487-93 – Unified Soil identification and
Classification. ASTM International, West Conshohocken, PA,
19428-2959, United State of America
BS1377 (1990). Specification for Roads and Bridges in Nigeria. Vol. 2,
pp. 137-275.
Eze E. O., Adeyemi. G. O. and Fasanmade P. A. (2014). Variability in
Some Geotechnical Properties of Three Lateritic Sub-Base Soils
© 2020 The Author(s). Published by Faculty of Engineering, Federal University Oye-Ekiti.
211
This is an open access article under the CC BY NC license. (https://creativecommons.org/licenses/by-nc/4.0/)
http://dx.doi.org/10.46792/fuoyejet.v5i2.495
engineering.fuoye.edu.ng/journal
FUOYE Journal of Engineering and Technology (FUOYEJET), Vol. 5, Issue 2, September 2020
Along Ibadan Oyo Road. IOSR Journal of Applied Geology and
Geophysics. Vol 2:5, pp 76-81
Federal Ministry of Works and Housing (1997) General Specification
for Roads and Bridges, Federal Highway Depart-ment, FMWH:
Lagos, Nigeria, vol. 2, pp. 317.
Garg, S. K. (2009). Soil Mechanics and Foundation Engineering.
,Khana publishers, New Delhi vol 7, No 1, pp. 673–683.
Gidigasu, M.D. (1976). “Lateritic Soil Engineering” Elsevier Scientific
Publishing
Company
Amsterdam
http://en.wikipedia.org/wiki/polyethylene,polyethylene,
Accessed
date August 8, 2006.
Inan, I.I.I, Mampearachchi, W.K, and Udayanga, P.A.S (2016) Effect
of fine percentage on the properties of sub-base material
Engineer (The Institution of Engineers, Sri Lanka). Vol XLIX, No.
4, pp 15 – 25.
Ola, S. A. (1983). Geotechnical behaviour of some Nigerian lateritic
soils. Published in “Tropical Soils of Nigeria in Engineering
Practice”, edited by Ola, S.A. (pp. 85-101): A.A.
Balkema/Rotterdam
Okeke,
O.C.,
Ogbunyiba,O.O.
and
Chukwujekwu,
D.
(2013).Geotechnical Evaluation of Lateritic Soil Deposits in parts
of Abuja (Nigeria), for Road Construction”. International Journal
of Environmental Issues, vol 10 No. 1, pp. 148-160.
Osinubi, K.J. (1998a), Influence of compactive efforts and
compaction delays on lime treated soils, Journal of Transportation
Engineering. A.S.C.E., vol. 124 No 2, pp 149-155.
Osinubi, K.J. (1998b), Pemeability of Lime treated laterite soil,
Journal of Transportation Engineering, A.S.C.E vol 124, No 5, pp.
456-469.
Sreedhar, M.V.S and Fatima, Z. (2017), Influence of plastic fines on
compaction and CBR characteristics of soil mixtures.
International journal of Engineering Research and Technology,
Vol. 6, No. 7, pp 233-239.
Yoder, E.J. and Witczak, M.W. (1975) “Principle of Pavement
Design”. John Wiley & Sons, Hoboken, vol 1, No 2, pp. 711
Younoussa M, Karfa T, Raguilnaba O, Kalsibiri K, Philippe B, and
Jean H. (2008) Geotechnical, mechanical, chemical and
mineralogical characterization of lateritic gravels of Sapouy
(Burkina Faso) used in road construction. Construction and
Building Materials (Elsevier). Vol. 22, pp 70– 76.
ISSN: 2579-0625 (Online), 2579-0617 (Paper)
APPENDIX
MAP OF STUDY AREA
© 2020 The Author(s). Published by Faculty of Engineering, Federal University Oye-Ekiti.
212
This is an open access article under the CC BY NC license. (https://creativecommons.org/licenses/by-nc/4.0/)
http://dx.doi.org/10.46792/fuoyejet.v5i2.495
engineering.fuoye.edu.ng/journal