: –Type of Stones
|Physical Classification||Chemical Classification
|Igneous Rocks – rocks are formed by cooling and solidifying of the rock masses from
their molten magmatic condition of the material of the earth
|Stratified Rocks rocks are having layered structure. They possess planes of
stratification or cleavage
|Silicious rocks The main content of these rocks is silica. They are hard and durable. Examples
of such rocks are granite, trap, sand stones etc
|Sedimentary rock – Due to weathering action of water, wind and frost existing rocks
disintegrates. The disintegrated material is carried by wind and water; the water being most powerful
medium. Flowing water deposits its suspended materials at some points of obstacles to its flow. These
deposited layers of materials get consolidated under pressure and by heat
|Unstratified Rocks rocks are not stratified. They possess crystalline and compact
grains. They cannot be split in to thin slab.
|Argillaceous rocks –main constituent of these rocks is argil i.e., clay. These stones are
hard and durable but they are brittle. They cannot withstand shock
|Metamorphic rock – igneous and sedimentary rocks under go changes
due to metamorphic action of pressure and internal heat.
Foliated Rocks rocks have a tendency to split along a definite direction only. The
Calcareous rocks–The main constituent of these rocks is calcium carbonate. Limestone is a calcareous rock of sedimentary origin while marble is a calcareous rock of metamorphic origin.
Brick is obtained by moulding good clay into a block, which is dried and then burnt. This is the oldest building block to replace stone. Manufacture of brick started with hand moulding, sun drying and burning in clamps.
Types of Bricks
(i) Building bricks
(ii) Paving bricks
(iii) Fire bricks
(iv) Special bricks.
Timber refers to wood used for construction works. In fact, the word timber is derived from an old English word ‘Timbrian’ which means ‘to build’
On the basis of mode of growth trees are classified as (a) Exogeneous and (b) Endogeneous
(a) Exogeneous Trees: These trees grow outward by adding distinct consecutive ring every year. These rings are known as annual rings. Hence it is possible to find the age of timber by counting these annual rings. These trees may be further divided into
(1) coniferrous and (2) deciduous.
Coniferrous trees are having cone-shaped leaves and fruits. The leaves do not fall till new ones are grown. They yield soft wood.
Deciduous trees are having broad leaves. These leaves fall in autumn and new ones appear in springs. They yield strong wood and hence they are commonly used in building construction.
(b) Endogeneous Trees: These trees grow inwards. Fresh fibrous mass is in the innermost portion. Examples of endogenous trees are bamboo and cane. They are not useful for structural works.
Cement is a commonly used binding material in the construction. The cement is obtained by burning a mixture of calcarious (calcium) and argillaceous (clay) material at a very high temperature and then grinding the clinker so produced to a fine powder.
Types of Cement
In addition to ordinary portland cement, there are many varieties of cement. Important varieties are
briefly explained below:
(i) White Cement
(ii) Coloured Cement
(iii) Quick Setting Cement
(iv) Rapid Hardening Cement
(v) Low Heat Cement
(vi) Pozzolana Cement
(vii) Expanding Cement
(viii) High Alumina Cement
(ix) Blast Furnace Cement
(x) Acid Resistant Cement
(xi) Sulphate Resistant Cement
(xii) Fly Ash Blended Cement