Soil is the cheapest and the most widely used material in civil engineering
projects as foundation material either in its natural or improved form. It is highly
heterogenous and an isotropic in nature and existing with different engineering
properties which can be influenced to some extent by the presence of copper
salt under the influence of water (Kadiyah and Lal, 2006).
The properties of soil as engineering material depends on its surface
electrical charges, chemical composition size and shape e.t.c. The chemical
composition influences the exhibition of enormous changes in the engineering
properties especially in soil with high content of clay materials (Singh and Singh,
The geotechnical characteristics of soil are of great importance. The
degree of these properties within certain range has a useful meaning in
determining the best and suitability of it, for engineering construction especially
for road construction (Ola, 2005).
1.1 Lateritic Soil
Laterite is well known in Asian countries as a building material for more
than 1000 years. It was excavated from the soil and cut in form of large blocks;
temples at Angkor are famous, examples for this early use.
Laterite is one of the most valuable materials for building. It is diffused in
immense masses, without any appearance of stratification and is placed over the
granite that forms the basis of Malayala. It is full of cavities and pores, and
contains a very large quantity of iron in the form of yellow and red ochres. In the
mass while excluded from the air, it is so soft, that any iron instrument readily
cuts it, and is dug up in square masses with a pick-axe, and immediately cut into
the shape wanted with a trowel, or large knife. It very soon after becomes as
hard as brick and resists the air and water much better than any brick (Werner
The engineering behaviour of laterite material from trial pits is influenced
by some factors which includes origin degree of weathering, mineral
composition, environmental condition e.t.c. (Umebulues, 2001).
The result of these properties helps a lot and will serve as a guide in
prospective works. This will also provide engineers with quick method of
checking which material is best fit on the alternative for road construction
1.0.1 The importance of laterite as building material has already been
mentioned. More relevant as their local use for the construction of simple houses
in their application as a road building material. The suitability of lateritic
materials above all of lateritic gravel is tested by several methods of engineering
1.1 Statement of the Problem
Misunderstanding soils and their properties can lead to construction errors.
The suitability of a soil for a particular use should be determined based on it
engineering characteristics and not on usual inspection or apparent similarity to
Some particles of laterite tend to crush easily under impart disintegrating
into a soil may be self hardening when exposed to drying or if they are not self
hardening, they may contain appreciable amounts of hardened lateritic rock or
1.2 Aim and Objectives
The aim and objectives of this project include:
1. To determine how suitable and durable the available laterite material in
Ilorin East Local Government is for road construction.
2. To carryout some geotechnical tests required for the strength evaluation of
laterite material in order to determine its constructional suitability in road
3. To determine the strength of laterite and its durability.
4. To determine whether these laterite materials meet the American Standard
Test Method (ASTM) specification for road construction.
5. To draw conclusion and recommendation from the evaluation as a
standard for prescription of trial pits selected in Ilorin East Local
Government Area to Engineers and Construction Industries.
1.3 Justification of Study
Due to the fact that laterite is a paramount material in the construction of
road, it has to be investigated to determine its suitability for the construction of
1.4 Scope of the Project
The knowledge of the use of laterite for road construction is increasingly
going far and wide over the years.
For the purpose of this research, the study shall be limited to Ilorin East
Local Government Area of Kwara State in which the following laboratory test will
be carried out on each samples of soil, the laboratory test are particle size
distribution test. Atterberg’s limit test, compaction test, Natural Moisture Content
and Califonia Bearing Ratio (CBR) test.
This project will deal with the field and laboratory test of laterite material
for road construction. Three different trial pit in Ilorin East Local Government
Area will be selected.
The sample will be collected from three trial pit locations and will be
The engineering tests required for strength evaluation will be carried out
such tests include CBR, Atterberg limit test, particle size distribution test,
compaction test and natural moisture content.
The analysis of the result follows and the conclusion and recommendation