1.0 INTRODUCTION

Cement can be defined as the hydraulic binding materials used for

construction purposes. Hydraulic means ability of substance to set or harden when

exposed to moisture. The word ‘cement’ originated from the latin word “cementrum”

which was then Greek construction material. The history can be attributed to the work

in 1824 of a British gentleman Joseph Aspidin.

Portland cement is a name given to cement obtain by intimately mixing

together calcareous and argillaceous or other silica such as iron and alumina oxide.

The properties of the final product of Portland cements are dependent on the

chemical and morphological composition of clinker gypsum and other addition

introduced during process of grinding. Changes in cement properties could occur

during process of grinding. Changes in cement properties could occur during

subsequent storage. Since the cement quality can be overwhelmingly dependent on

the quality of clinker. It therefore means that any consideration of its characteristics

require a basic understanding of the factors that construct the clinker quality and

clinkerization process.

1.1 Problem statement

The demand for cement has increased more than six fold during the last two

decades precisely from 133 tones in 1950 to 860 million tons in 1979 (S.P Ghosh).

At the same time there has been tremendous technological progress in the

manufacturing process which is continuously updated through the introduction of new

technologies for capacity enhancement as well as by various devices for energy and

material conservation.

Building activities are on the increase in Nigeria this is due to growth in

population and the need for individual to own a house .Cement plays a major role in

building activities hence there is the need to analyze and determine the constituent of

cement this can only be achieved through its chemical composition and physical

characteristics.

Physico-chemical characterization of Nigerian cement will properly address

issues of building standard by fully experimenting the indigenous cement and

comparing it with international ASTM and British standard

The research will classify cement type based on its suitability to various uses

such as loading or desirability to the environment

1.2 Aims and Objectives of Study

The assessment of cement characterization and quality relies in direct

performance test because of the complexity of the factors influencing the rate of

hydration and the hydraulicity of cement.

Literature studies reveals that the value obtained for the basic composition

physical properties etc is particularly method dependent so that a prescribe procedure

must be followed and named when referring to result obtained. This is not usually the

case in our assessment of various brands of cement in Nigeria.

The major objectives of this study are:

1. Develop a standard specification method based on the chemical composition

and physical characteristics of the Nigeria cement.

2. Develop a classification guideline for purchasers and users by specifying

primary properties requirement influencing its qualities and area of

applications.

1.3 Scope of work

A preliminary survey on the different types of cement available in Nigeria was

done and their relative availability considered.

Sampling points include all the six geographical zone in Nigeria these are as

follows:

i. Ashaka Cement in North Eastern Zone

ii. Sokoto Cement in North-Western Zone

iii. Benue Cement in Middle-Belt

iv. West African Portland Cement in South West

v. The Nigerian Cement Nkalagu in South East

vi. The Calabar Cement Calcemus in South-South

In addition two imported cement Dangote Cement and Burham Cement will

also be considered for the research work

However due to complete shutdown of most indigenous cement companies in

Southern and Eastern region of Nigeria only those in the Northern region are available

for the research work.

The parameters to be measured are:

1. The bulk chemical composition of the cement the cement was analysed to

determine the percentage composition of

i. Silicon oxide SiO2

ii. Calcium oxide CaO

iii. Iron oxide Fe2O3

iv. Aluminium oxide Al2O3

v. Magnesium oxide MgO

vi. Sulphur trioxide SO3

2. Particle size composition

3. Setting time of the cement

4. Comprehensive strength of the cement

5. Soundness of the cement

6. Consistency of the cement

1.4 Justification

The British standard protects the purchaser of cement by specifying

requirement for those properties primarily influencing its quality. It is important that

the Nigerian cement conforms to the set of international required standard.

In practice cement structure durability that is resistance to aggressive agent is

determined largely by concrete permeability and it is influence by the efficiency with

which hydration product filled the void between the grains of aggregates. Poor

conformity of structures to establish guidelines leads to the development of its

degradation. This has necessitated investigation into the basic raw materials

composition the finished products and other factors that could ensure longer service

life for cement based structures.

Therefore with the present socio economic development and the envisaged

technological advancement the increase demand for cement cannot be

overemphasized. It has become necessary to characterized available cement and

effectively determines the area of application.