I welcomed you to the world of building materials and construction in the preceding blog Basic of civil engineering; Simple and in-depth guide. Here, we are going to meet the frontbenchers in the list. They are,
Stones, bricks, cement and lime.
So, ready to shake hands with the first one?
Okay. Good to go.
1. STONES-Introducing first building material
Stone is a naturally available building material that has been used for construction from the early age of civilization.
Types of stones
The classification of stones are as follows.
i) Igneous Rocks: These rocks are formed by cooling and solidifying of the rock masses from their molten magmatic condition of the material of the earth.Eg: Trap and basalt
ii) Sedimentary Rocks: Due to weathering action of water Eg: Sand stones, lime stones
iii) Metamorphic Rocks: Previously formed igneous and sedimentary rocks under go changes due to metamorphic action of pressure and internal heat Eg: quartzite, marble
i) Stratified rocks Sand stones, lime stones
ii) Unstratified rocks Granite, trap, marble
i) Silicious rocks: The main content of these rocks is silica. Examples are granite, trap, sand stones etc.
ii) Argillaceous rocks: The main constituent of these rocks is clay. Eg. Slates and laterites.
iii) Calcareous rocks: The main constituent of these rocks is calcium carbonate. Eg. Limestone
Had any idea there existed such varieties of stones?
Now let me list out the important properties of stone that make you choose it for your building.
Properties of stone
- Percentage wear
- Porosity and Absorption
- Resistance to Fire
- Ease in Dressing
Before thinking about considering stone for your next building, have a close look at the following tests on stones.
Tests on Stones
(i) crushing strength test
(ii) water absorption test
(iii) abrasion test
(iv) impact test
(v) acid test
So, tests are done. Now, let me tell you, where all you can use this building material.
Uses of Stones
(i) Stone masonry is used for the construction of foundations, walls, columns and arches.
(ii) Stones are used for flooring.
(iii) Stone slabs are used as damp proof courses, lintels and even as roofing materials.
(iv) Stones with good appearance are used for the face works of buildings. Polished marbles and granite are commonly used for face works.
(v) Stones are used for paving of roads, footpaths and open spaces round the buildings.
(vi) Stones are also used in the constructions of piers and abutments of bridges, dams and retaining walls.
(vii) Crushed stones with graved are used to provide base course for roads. When mixed with tar they form finishing coat.
Wah! Lots of possible applications, right?
Moving on to the next building material, it’s none other than the lovely bricks.
2. Brick- Introducing second building material
Brick, the next in the category of building materials is obtained by molding good clay into a block, which is dried and then burnt.
Now, bricks being one among the inevitable materials in the building and construction sector, let’s know it deeper.
Types of Bricks
Major types of bricks are,
(i) Building Bricks
These bricks are used for the construction of walls.
(ii) Paving Bricks
These are vitrified bricks and are used as pavers.
(iv) Special Bricks
These bricks are different from the commonly used building bricks with respect to their shape and the purpose for which they are made.
Figure shows example of special bricks
Some of such bricks are listed below:
(a) Specially Shaped Bricks
Bricks of special shapes are manufactured to meet the requirements of different situations.
(b) Facing Bricks
These bricks are used in the outer face of masonry. Once these bricks are provided, plastering is not required. The standard size of these bricks are 190 × 90 × 90 mm or 190 × 90 × 40 mm.
(c) Perforated Building Bricks
These bricks are manufactured with area of perforation of 30 to 45 per cent. The area of each perforation should not exceed 500 mm2. The perforation should be uniformly distributed over the surface. They are manufactured in the size 190 × 190 × 90 mm and 290 × 90 × 90 mm.
(d) Burn’t Clay Hollow Bricks:
Bricks are used for the construction of partition walls. They provide good thermal insulation to buildings. They are manufactured in the sizes 190 × 190 × 90 mm, 290 × 90 × 90 mm and 290 × 140 × 90 mm. The thickness of any shell should not be less than 11 mm and that of any web not less than 8 mm. WEBS 8 mm minimum thick Fig. 1.4. Hollow bricks
(e) Sewer Bricks
These bricks are used for the construction of sewage lines. They are manufactured from surface clay, fire clay shale or with the combination of these. They are manufactured in the sizes 190 × 90 × 90 mm and 190 × 90 × 40 mm. The average strength of these bricks should be a minimum of 17.5 N/mm2 . The water absorption should not be more than 10 per cent.
( f ) Acid Resistant Bricks
These bricks are used for floorings likely to be subjected to acid attacks, lining of chambers in chemical plants, lining of sewers carrying industrial wastes etc. They are made of clay or shale of suitable composition with low lime and iron content, flint or sand and vitrified at high temperature in a ceramic kiln.
Expanding the little information, let’s see the properties of bricks.
Properties of Bricks
Colour should be uniform and bright.
Bricks should have plane faces. They should have sharp and true right angled corners.
Bricks should be of standard sizes as prescribed by codes.
They should possess fine, dense and uniform texture. They should not possess fissures, cavities, loose grit and unburnt lime.
When struck with hammer or with another brick, it should produce metallic sound.
Finger scratching should not produce any impression on the brick.
Crushing strength of brick should not be less than 3.5 N/mm2. A field test for strength is that when dropped from a height of 0.9 m to 1.0 mm on a hard ground, the brick should not break into pieces.
(viii) Water Absorption
After immercing the brick in water for 24 hours, water absorption should not be more than 20 per cent by weight. For class-I works this limit is 15 per cent.
Bricks should not show white patches when soaked in water for 24 hours and then allowed to dry in shade. White patches are due to the presence of sulphate of calcium, magnesium and potassium. They keep the masonry permanently in damp and wet conditions.
(x) Thermal Conductivity
Bricks should have low thermal conductivity, so that buildings built with them are cool in summer and warm in winter.
So, like you tested the stones to know whether its suitable for the work you intended, why not sneak into the tests on bricks?
Tests on Bricks
(i) Crushing strength
(iii) Shape and size and
Going on, let’s see the main uses of bricks below.
Uses of Bricks
(i) As building blocks.
(ii) For lining of ovens, furnaces and chimneys.
(iii) For protecting steel columns from fire.
(iv) As aggregates in providing water proofing to R.C.C. roofs.
(v) For pavers for footpaths and cycle tracks.
(vi) For lining sewer lines.
How was your time with bricks?
Alright. We are good to meet the last one now.
3. Lime- Introducing third building material
It is one of the oldest binding materials used in building construction. When it is mixed with sand it provides lime mortar and when mixed with sand and coarse aggregate, it forms lime concrete.
The major types of lime are,
- Fat lime
- Hydraulic lime
- Poor lime
And important tests on limestones are,
Tests on Limestones
(i) Physical tests
(ii) Heat test
(iii) Chemical test
(iv) Ball test
Last, but not the least,
Uses of lime are,
(i) For white washing.
(ii) For making mortar for masonry works and plastering.
(iii) To produce lime sand bricks.
(iv) For soil stabilization.
(v) As a refractory material for lining open hearth furnaces.
(vi) For making cement.
Alright. Heading onto the last member,
4. Cement- Introducing fourth building material
This is an important member of the building materials and construction sector. We have discussed the ingredients, properties of Cement, the manufacturing process, and the field tests in previous blogs.
I hope you got an understanding about these major building materials and their application in the construction sector.
We are looking forward to hear your feed backs.