Construction Hints

Production of Portland cement starts with two basic materials; a Calcareous material and an Argillaceous material.  The calcareous material is a calcium oxide, such as limestone, chalk, or oyster shells, the Argillaceous material is combination of alumina and silica obtainable from clay, shale, and blast furnace. the materials are passed through a grinding mill, using wet or dry process to the kiln.  In the kiln, the raw materials are melted at temperature of 1400 oC  to 1650 oC,  changing the raw materials into Cement clinker which is then cooled  and stored. The final process involved grinding the clinker into a fine powder, adding gypsum to regulate the setting time if the cement in the concrete. The final product can be transported in stored bulk or sacks.

Portland Cement concrete is most widely used manufacturing construction material...it is very important in the construction field, it is used in structures such as buildings, pavements, Dams,factories, bridges etc. Portland Cement concrete main constituents is the Portland Cement ( i.e Dangote cement) ,aggregates, water, air voids,  and in some cases, admixtures. Portland Cement is an instant glue when water is added to it and bonds aggregate to together to make Portland Cement concrete.

These are materials (usually metals) which have unfilled valence bond and thus provide vacant energy states into which electrons in the valence state can move. The movement of electrons is an electric field is facilitated by gain of velocity and momentum as it moves towards the positive electrode. This is due to added energy which therefore requires an occupied energy State at a higher level. Example of conductors are Cu, All, Fe, etc. Metals with few electrons in their valence make excellent conductors of electricity. Forms of conductor are wires, cables and bus-bars (rods, tube etc)

An aggregate can be defined as the material comprising of percentage required of gravel, crushed stone, and sharp sand of their specific size of particle mixed together at a required ratio to form part of concrete mortal. Aggregates can be classified as Natural and Artificial. Natural Aggregates: Coarse Aggregates, fine Aggregates, Sand  and gravel Aggregates, Granite Aggregates,

These are metals in which the valence band are completely filled and electrons are readily available for movement into the conduction band and creating an electron-hole pair in the structure of the material and apparent electrical conditions. Examples of semi conductor materials are group IV elements such as carbon, silicon, germanium, tin. Semi conductor can be classified into two forms : Intrinsic and Extrinsic semi conductor

The Strain developed in a material is directly proportional to the Stress producing it. Thus there is linear relationship between stress and strain which is tenable within certain limits for most materials

Stress: This is the intensity of the internal force, which is the magnitude of the sum of forces within a section, is divided by the cross-section. Stress = F/A. (N/m²) Strain: This is the change in the dimension(s) of a material in a state of stress. It can either be comprehensive or tensile. Tensile stress results in extension  of length while comprehensive stress shortens the length of a material. Strain = L-Lo/ Lo