Performance of lateritic concrete under environmental harsh condition

IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
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Volume: 02 Issue: 08 | Aug-2013, Available @ http://www.ijret.org 144
PERFORMANCE OF LATERITIC CONCRETE UNDER
ENVIRONMENTAL HARSH CONDITION
Olubisi A. Ige
Department of Civil Engineering, Osun State Polytechnic, Iree. bisiige@gmail.com.
Abstract
This is an investigation of weathering characteristics of Laterized concrete with laterite-fine aggregate ratio as a factor. It was done
with a view of ascertaining the suitability of laterite as aggregate substitutes at 0, 10, 20, 30 and 40% of fine aggregate used in the
construction industry. The weathering characteristics were examined by conditioning laterized concrete cubes to varying
temperatures, chemical and alternate wetting and drying, which all represent the operating weather conditions (wet and dry seasons)
in tropics, including Nigeria. The mix proportion used was 1:2:4, the curing age of the laterized concrete was based on 28days
curing age, while the compressive strength of the treated laterized concrete cubes was determined. The result of this research showed
that the compressive strength of laterized concrete with laterite-fine aggregate ratio variation decreases when subjected to alternate
wetting and drying and increases when subjected to magnesium sulphate (Mg2SO4). It was also discovered that a laterized concrete
with a laterite-fine aggregate ratio of 20% conditioned to a temperature range of 100o
C attained optimum compressive strength of
12.90Nmm-2
Keywords: Laterized Concrete, Comprehensive strength, Weathering Characteristics.
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1. INTRODUCTION
Large areas in the tropical and subtropical regions of the world
are covered by lateritic formations, which include soil and
concretions. Soil and concretions, which are latter being the
lateritic aggregate, are components, which are widely used for
civil engineering purposes. In construction industry, the most
widely used material is concrete which is obtained by mixing
cementitious materials, water and aggregates. The mixture
when placed in forms and allowed to cure hardens into a rock-
like mass known as hardened concrete. The hardening is
caused by chemical reaction between water and cement and it
continues for a long time. It may also be considered as an
artificial stone in which the voids of larger particles (coarse
aggregate) are filled by the smaller particles (fine aggregates)
and the voids of fine aggregates are filled with cement. The
strength, durability and other characteristics of concrete
depend upon the properties of its ingredients, on the
proportions of mix, the method of compaction and other
controls during placing, and curing.
Nowadays, with the advancement of technology, a lot of
researches have been carried out to discover the new concrete
technology. Hasniza [1] noted that in accordance with the
Ninth Malaysian plan, government also encourages publics to
be involved in the Research and Development (R & D) in
construction industry. One of the researches done in concrete
technology is a study to find any material that can be used as a
replacement material in concrete mixture [2]. The materials
that show any likely potential to be used as a replacement
material such as steel, latex, quarry dust, lateritic soil and glass
are being investigated. This research is important to
construction industry because it is not only possible if the
conventional raw material such as sand and granite
(aggregate) used in concrete mix will run out, but the research
also will cut down the cost of construction [3].
In this study, the focus will give more to the research about
laterite soil used as an aggregate substitute in the concrete
mixture. Usually, the normal concrete contains cement, fine
aggregate (sand) and coarse aggregate (granite). However, for
this study granite will serve as coarse aggregate and then
laterite soil will be added into the mixture in certain
percentage of sand (fine aggregate). This present study, which
studies the performance of lateritic concrete under
environmental harsh condition, form part of the efforts aimed
at fully integrating laterized concrete for structural use in
construction works. This was done by subjecting laterized
concrete to varying temperatures, chemicals such as
magnesium sulphate (Mg2SO4) and alternate wetting and
drying, while still varying laterite-sharp sand ratio as fine
aggregate.
2. RESEARCH METHODOLOGY
The lateritic soil used was obtained from a nearby borrow pit
at the Faculty of Science, Osun State Polytechnic, Iree. The
material was air dried and a sample was subjected to sieve
analysis using the manual sieve shaker with sieves BS No 4, 8,
16, 20, 40, 70, 100 and 200. The granite (coarse) and sand

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(fine aggregates) used were obtained from a construction site
along Iree – Eripa road, Osun State Nigeria and found to be
suitable as specified by [4]. The cement used for this
experiment was the Ordinary Portland Cement in accordance
to [5] produced by the West African Portland Cement
Company, Nigeria. It is the brand widely used in the
construction industry and also readily available. A potable
water free from impurities in compliance with [6] was used in
carrying out the experiment. The water-cement ratio used for
the project was based on the optimum water-cement ratio
given by [7] and [8].
2.1 Production of Cubes
Batching of materials was done by weight using semi
automatic scale at the 20kg range. The manual method of
mixing, using shovels and trowels, was adopted while the mix
ratio used was 1:2:4. The sand-laterite ratio used as fine
aggregate were 0, 10, 20, 30, and 40%, this was to ascertain
the range of combination that will give optimum compressive
strength [9]. The mixing was done such that the dry
components were mixed until a satisfactory uniform colour
was obtained with desired water being added gradually to the
mixed dry components and thorough mixing done to give a
workable concrete [10]. The moulds (150 x 150 x 150) mm3
were used in casting the cubes. Four replicates were made for
each laterite-aggregate ratio variation. The curing of cubes
was based on 28 days curing age using the curing tank located
at civil engineering department of Osun State Polytechnic,
Iree.
Two of the four replicates of the cured cubes for each ratio
variation of 0, 10, 20, 30 and 40%, respectively were
subjected to temperature of 50 and 100oC for two hours using
an oven. The temperature treatment continued in this trend for
each of the ratio variations. The temperature was applied to
subject the specimens to the dry season, which operates in the
tropics.
One of the remaining three replicates of the cured cubes was
subjected to alternate wetting and drying. This was done such
that replicates were first dried at 50oC for 2 hours (because in
recent times the highest temperature recorded in Nigeria was
400C, 50oC was thus used to give allowance for any possible
increment) and then immersed in water at room temperature
for 1 hour. These were repeated in three cycles, making use of
the drying oven. The alternate wetting and drying was done to
subject the specimens to factors of weathering (i.e. rainy and
dry seasons) that are operating in the tropics. Others were
subjected to chemical such as magnesium sulphate (Mg2SO4)
to determine its performance under environmental harsh
condition.
2.2 Crushing of Cubes
After each cube had been subjected to the desired conditions,
their crushing loads were determined using the Avery-
Denilson Testing Machine. The cubes were weighed before
crushing to facilitate the determination of densities.
3. RESULTS AND DISCUSSION
3.1 Sieve Analysis
The results of sieve analysis of the laterite used are shown in
table 1.1 and the grading curve is also shown in chat1.
Analysis of the results showed that the laterite used in this
experiment is well graded.
Table 1: Results of Sieve Analysis of Laterite
Sieve No Sieve
Opening
Weight of
Sieve (g)
Weight of
Sieve + soil (g)
Weight of soil
Retained (g)
Retained (%) Passing (%)
4 4.760 400 650 250 18.12 81.88
8 2.360 1000 1400 400 28.99 52.89
16 1.180 400 500 100 7.25 45.64
20 0.850 350 600 250 18.12 27.52
40 0.425 350 480 130 9.42 18.10
70 0.212 300 350 50 3.62 14.48
100 0.150 280 300 20 1.45 13.03
200 0.075 220 250 30 2.17 10.86
Rec Pan - 500 650 150 10.87 -
Type of Soil: Laterite, Total weight: 1380g.

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The observed crushing loads of the cubes for laterite- fine
aggregate ratio variation of 0, 10, 20, 30 and 40%, magnesium
sulphate (Mg2SO4) and alternate wetting and drying
respectively are shown below. The observed values are
temperature, volume, effective area, weight and crushing load
of each cube, which had been subjected to desired conditions.
The analyses are as represented in Tables 2 to 8 under column
headings weight, density, crushing load and compressive
strength.
SIEVE SIZE (µm)
Chart 1: Grading Curve of Sieve Analysis of Laterite Soil
Table 2: Compressive strength and density of laterized concrete at 0% laterite-fine ratio
Temperature(o
C) Weight
(kg)
Volume
(m3
)
Density
(KN/m3
)
Crushing
load (KN)
Effective
area
(mm2
)
Compressive
Strength
(N/mm2
)
50 8.10 0.153
23.08 320 1502
14.22
100 8.08 0.153
23.02 317 1502
14.09
Table 3: Compressive strength and density of laterized concrete at 10% laterite-fine ratio
Temperature(o
C) Weight
(kg)
Volume
(m3
)
Density
(KN/m3
)
Crushing
load (KN)
Effective
area
(mm2
)
Compressive
Strength
(N/mm2
)
50 7.69 0.153
21.91 290 1502
12.90
100 7.67 0.153
21.85 285 1502
12.60
Table 4: Compressive Strength and density of laterized concrete at 20% laterite- fine ratio
Temperature(o
C) Weight
(kg)
Volume
(m3
)
Density
(KN/m3
)
Crushing
load (KN)
Effective
area
(mm2
)
Compressive
Strength
(N/mm2
)
50 7.77 0.153
22.14 280 1502
12.40
100 7.70 0.153
21.94 290 1502
12.90
PERCENTAGEPASSING(%)

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Table 5: Compressive strength and density of laterized concrete at 30% laterite- fine ratio.
Temperature(o
C) Weight
(kg)
Volume
(m3
)
Density
(KN/m3
)
Crushing
load (KN)
Effective
area
(mm2
)
Compressive
Strength
(N/mm2
)
50 8.05 0.153
22.93 220 1502
9.8
100 8.02 0.153
22.85 200 1502
8.8
Table 6: Compressive strength and density of laterized concrete at 40% laterite- fine ratio.
Temperature(o
C) Weight
(kg)
Volume
(m3
)
Density
(KN/m3
)
Crushing
load (KN)
Effective
area
(mm2
)
Compressive
Strength
(N/mm2
)
50 8.18 0.153
23.30 190 1502
8.4
100 8.10 0.153
23.08 200 1502
8.8
Table 7: Compressive strength and density of laterized concrete subjected to magnesium sulphate (Mg2SO4).
Ratio
variation
(%)
Weight (kg)
Initial Final
Volume
(m3
)
Density (KN/m3
Initial Final
Crushing
load
(KN)
Effective
area
(mm2
)
Compressive
strength
(N/mm2
)
0 8.40 8.37 0.153
23..93 23.85 330 1502
14.67
10 8.32 8.43 0.153
23.70 24.02 310 1502
13.78
20 7.98 7.85 0.153
22.74 22.36 320 1502
14.22
30 7.90 7.94 0.153
22.51 22.62 290 1502
12.90
40 8.05 8.01 0.153
22.93 22.82 220 1502
9.80
LATERITE- FINE AGGREGATE RATIO (%)
Chart 2: Effect of magnesium sulphate (Mg2SO4) on the compressive strength of laterized concrete
Table 8: Compressive strength and density of laterized concrete subjected to alternate wetting and drying
Ratio
variation
(%)
Weight (kg)
Initial Final
Volume
(m3
)
Density (KN/m3
Initial Final
Crushing
load
(KN)
Effective
area
(mm2
)
Compressive
strength
(N/mm2
)
0 8.10 8.15 0.153
23..08 23.22 316 1502
14.04
10 7.72 7.74 0.153
21.94 25.05 310 1502
13.78
20 7.73 7.78 0.153
22.02 22.17 390 1502
12.90
30 7.80 7.92 0.153
22.22 22.56 210 1502
9.30
40 8.25 8.28 0.153
23.50 23.59 200 1502
8.80
COMPREHENSIVESTRENGTH
(N/MM2
)

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LATERITE- FINE AGGRIGATE RATIO (%)
Chart 3: Effect of alternative wetting and drying on the compressive strength of laterized concrete.
Chart 2 shows the effect of magnesium sulphate on the
compressive strength at the varying laterite-fine aggregate
ratio. Chart 3 shows the effect of alternate wetting and drying
on the compressive strength of laterized concrete at varying
laterite-fine aggregate ratio, the chart also compares the
compressive strength at the varying laterite-granite fine ratio
for alternate wetting and drying with the maximum
compressive strength for each percentage laterite-fine
aggregate ratio variation.
3.2 Discussion
Considering the effect of temperature on the compressive
strength of laterized concrete, it shows that for some of the
laterized concrete cubes, especially those with laterite-fine
aggregate ratio of 20 and 40% with concrete mix 1:2:4 at a
curing age of 28 days, temperature had an appreciable impact
on the compressive strength of the laterized concrete from 50
– 100oC. For instance, the 20% laterite- fine aggregate ratio
has the compressive strength increased from 12.40N/mm2 to
12.90N/mm2, 4.03% increase for a temperature range of 50 –
100oC unlike the other percentage replacement, 10 and 30%
laterite- fine aggregate ratio in which the compressive strength
decreased after subjecting the cubes to increased temperature.
The plain concrete with 0% laterite even had its compressive
strength decreased from 14.22N/mm2 to 14.09N/mm2 , 0.9%
decrease for temperature range of 50 – 100oC.
From chart 2, studying the effect of magnesium sulphate on
the compressive strength of laterized concrete, it was found
that the compressive strength of a 20% laterite-fine aggregate
ratio when subjected to magnesium sulphate was
14.22N/mm2. Comparing this value with the compressive
strength of same 20% laterite-fine aggregate ratio of a
laterized concrete at temperature of 100oC, 12.90N/mm2, it
shows that there was an increase in the strength by 10.23%
when subjected to magnesium sulphate salt.
Also, studying the effect of alternate wetting and drying on the
compressive strength of 0% laterite-fine aggregate ratio, the
plain concrete, it was found that at temperature of 50oC,
compressive strength was 14.22N/mm2 while 14.04N/mm2 is
found to be the result after it is subjected to alternate wetting
and drying. It shows that there was a decrease in the strength
by 1.28% when subjected to alternate wetting and drying. This
was on the contrary at 20% laterite- sand ratio of laterized
concrete where the compressive strength was maintained.
CONCLUSIONS
The influence of high temperature, chemical and alternating
wet and dry condition on the compressive strength of laterized
concrete has been investigated. It was found that for laterised
concrete mix 1:2:4 and curing age of 28 days, with laterite-
fine aggregate ratio variation as a factor, 20% replacement of
fine aggregate by laterite had a reasonable compressive
strength for temperature applications up to 100oC whereas
plain concrete and other percentage replacement suffered a
reduction in compressive strength as the temperature
increases. The reason for this could be due to some other
inherent salts present in the laterite which may experience a
breakdown in their internal structure when subjected to
temperatures above 100oC, thus leading to a reduction in the
compressive strength of the laterized concrete, on the other
hand, the increase in compressive strength for 20%
replacement at temperature range of 100oC could be due to a
COMPRENESIVESTRENGHT(N/MM2
)

__________________________________________________________________________________________
gradual build up in the bond of the inherent salts present in the
laterite which thus lead to a high bearing capacity of the
laterized concrete.
Another conclusion drawn from the result of this study when
laterized concrete is subjected to alternate wetting and drying,
compressive strengths were as low as 9.30N/mm2. It implies
that laterized concrete depreciates with time under the
prevailing conditions (rainy and dry season) in the tropic.
Similarly, when the same laterized concrete is subjected to
magnesium sulphate (Mg2SO4), compressive strengths were
as high as 14.22N/mm2. It implies that laterized concrete
increases in strength when exposed to various metallic salts
solution.
Optimum compressive strengths could be obtained at 20%
laterized-fine aggregate ratio at temperature of 50 – 100oC.
It is thereby recommended that for any concrete works in
which laterite was to be used as a replacement or substitute for
fine on coarse aggregate, the laterite should be carefully
subjected to various test to ensure the suitability of the laterite
for concrete strength. Also, the laterized concrete should not
be exposed to constant rainy and dry season as it could result
in reduction of its compressive strength. Otherwise, it could be
subjected or exposed to magnesium sulphate salt (Mg2SO4) or
any other metallic salt which may improve its compressive
strength.
REFERENCES
[1] Hasniza B. H (2008). Effect of laterite soils as an
aggregate substitute on the hydraulic force and compression
strength of cube. Thesis, University Teknologi Malaysia.
[2] Lasisi, F and Osunade J. A(1984). Effect of grain size on
the strength of cubes made from lateritic soils, building and
environment, pergamon press, Great Britain.
[3] Oluwaseyi L. (2007). Influence of weather on the
performance of laterized concrete. Journal of Engineering and
Applied Sciences 2 (1); 129 – 135, 2007 ©Medwell journals,
2007
[4] Ige O. A (2008). Science and Properties of Materials.
Published by Sandbars Innovations Suite 62, Damin Plaza
Ring Road, Ibadan
[5] British Standard Institute, (1996) BS 12: Portland Cement
(ordinary and Rapid Heardening), BSI, London
[6] British Standard Institute, (1996) BS 5328: Part 1 and 2:
Guide to specifying concrete and methods for specifying
concrete mixes, BSI, London.
[7] Bwalya M. (2007). Utilization and improvement of lateric
gravels in road bases. International Institute for Aerospace
survey and Earth Sciences (ITC), Section Engineering
Geology, Kanaahveg 3, 2628 EB, Delft, the Netherlands.
[8] Falade, F. (1994). Influence of water/cement ratios and
mix proportions on workability and characteristics strength of
concrete containing laterite fine aggregate, Building and
Environment. Elsevier Science Great Britain.
[9] Osunade J. A. and Babalola, J. I. (1991). Effect of mix
proportion and reinforcement sixe on the anchorage bond
stress of laterized concrete, Building and Environment,
Pergamon Press, Great Britain.
[10]Grattan-Bellew P. E (2001). Petrographic and
technological methods for evaluation of concrete aggregates.
William Andrew Publishing and Noyes Retrieved January 14,
2012 from www.knovel.com.

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