What is defined a Stone Masonry?, What is Types of Rubble Masonry?

Stone Masonry 

When rock is quarried out and given rough shape at quarries it is called stone masonry. 

The stone masonry may be classified as follows 

Rubble Masonry 

In this masonry the stones of disorder sizes are used. 

The following of rubble masonry are given below.

• Coursed Rubble Masonry 

This is the rough and cheap way of stone walling.

 In this type of rubble masonry, the stones used are various sizes such as from 50 mm to 200 mm.

 This type of stone masonry is commonly used in the construction of public buildings residential buildings, etc.

 • Uncoursed Rubble Masonry

this type of rubble masonry, the stones are not formalize.

The courses are not maintained regularly. 

 • Random Rubble Masonry

 In this type of rubble masonry, the stones of irregular sizes and shapes are used. The stones are arranged, therefore as to have a good guise. 

Random Rubble Masonry  is used in residential building, compound wall, godown, etc.

 • Dry Rubble Masonry 

This type of rubble masonry is similar in construction to coursed rubble masonry except that no mortar is used in the joints. It is  used for compound walls, retaining walls and pitching on bridge approaches slab, etc. 

Ashlar masonry 

The square or rectangular blocks of stone are used in this type of masonry. 

The height of stone varies from 250 mm to 300 mm.

 The length of stones should not exceed three times the height and the depth into the wall should be at least equal to half the height.

Galvanized iron

Galvanized iron

 Galvanized sheet is a widely used building project material.

 this iron is coated with a zinc oxide finish, making it superior to plain steel.

  Galvanized iron is most often used in pipes, roofs, support, beams, wall braces, and residential framing.

Bitumen & Types of Bitumen

Bitumen

  Bitumen is the product obtained by fractional distillation of crude petroleum as an end product. 

• Bitumen becomes soft at moderate temperatures. It can be modified by heating until it becomes a liquid and then passing air under pressure by which all the volatile compounds in it can be driven out.

 The product is called "blown bitumen" (R grade).

Bitumen is available in the following forms:-

 (1)• Straight Run Bitumen

 It refers to bitumen distilled to a definite viscosity of penetration which does not require further treatment like heating.

 (2)• Penetration Grade

 It is the basic form of bitumen and has to be heated before application.

 (3)• Cutback Bitumen 

It is the bitumen combined with other petroleum distillates.

 This may be regarded as means of. applying penetration-grade bitumen at lower temperatures.

(5) • Bitumen Emulsion 

It is a product in liquid form formed in aqueous medium and stabilizing agents.

 This is also another means to obtain bitumen into a liquid form so that it can easily be applied at ambient temperature. 

(6)• Plastic Bitumen 

It consists of bitumen thinner and suitable filler made into a plastic form. As it is plastic, it can be used for filling cracks is masonry, stopping leakages, etc. 

(7)• Residual Bitumen 

It is a solid substance at normal temperature and is obtained as a residue during distillation of high-resin petroleum.

What is Composition of Brick Earth?

Composition of Brick Earth 

the main constituents of Earth for brick making are

 Silica or Sand

 A good brick earth contains about 50% to 60% of silica. 

Alumina or Clay 

A good brick earth contains about 20% to 30% of alumina.  

Lime 

A good brick earth contains up to 5% of lime. 

Magnesia 

A good brick earth contains up to 3% of magnesia. It is used for decreasing the shrinkage of bricks.

 Oxide of Iron 

A good brick earth contains up to 6% of iron oxide. It helps lime to fuse is silica and gives red colour to the bricks.

 it may be noted that 

(a) The excess of alumina in the clay (brick earth) makes the brick crack and warp during drying process. 

(b) The excess of silica in the clay makes the brick brittle and weak after burning. 

(c) The excess of lime in the clay causes the bricks to melt and distort during burning. 

(d) The alkaline salt present in the bricks, absorb moisture from air which on drying leaves powder deposit on the brick

 (e) This effect is known as efflorescence. It is also caused if the clay used for making bricks contain pyrite and the water used for pugging the clay contain gypsum. 

Manufacturing of Bricks  

 Preparation of Clay 

(I) After removal of vegetation, the clay deposit is excavated in steps rather than in layers to ensure a better distribution of the several constituents which vary in different proportions at different depths.Further processing of the clay depends on the type of bricks to be made.

 (ii)  For ordinary country bricks, very little preparation. except mixing by treading is resorted to. 

(iii)  For making first class facing bricks, the clay is allowed to weather by keeping it exposed to open air for a considerable period, so that the lumps of clay break down into smaller particles and get matured.

 (iv)  As a further refinement for making very superior bricks, the clay is washed and processed before moulding into bricks.

(v)  For making clay tiles also we use the clay that has been processed.

what is Bricks & What is Classification of Bricks.

Bricks

Bricks are block of tempered clay by plastic moulded to suitable shapes.

they are dried in Sun and then burnt therefore as to make them strong hard and durable.

the standard size of  bricks are 19 cm x 9 cm x 4 cm or 19 cm x 9 cm x 9 cm.

the specific gravity of bricks is about 2.

the no. of bricks contain for one cubic metre of brick masonry are 550.

Classification of Bricks

1.) First-Class  Brick

in this bricks are well burnt having smooth and even surface with perfect rectangular shape and uniform reddish colour.

these bricks should not absorb water more than 20% of its own dry weight after 24 hours immersion in water.

it should have a minimum crushing strength of 10.5 MN/m^2.

2.) Second Class Bricks 🧱

the second Class Bricks are slightly over burnt having rough surface and not perfectly rectangular in shape.

these bricks should not absorb water more than 22% of its own dry weight after 24 hours immersion in water.

3.) Third Class Bricks

Third Class Bricks are not properly burnt (under burnt) in the kiln and hence these are soft and can be easily broken. 

these bricks should not absorb water more than 25% of its own dry weight after 24 hours immersion in water.

4.) Jhama Bricks

Jhama bricks are over burnt with irregular shape.

these bricks are dark bluish in colour.

Wet Shotcrete Machine

The Wet Shotcrete Machine isused for Shotcrete work in metro and tunnel Construction

Important points of Civil Engineer

1.)  POINT OF CONTRAFLEXURE: 

The point of Contraflexure is a point whese Bending Moment changes its sign (BM is zero). 

 2.) GRADE OF CONCRETE & MIX PROPORTION: 

               C:S:A 

1.) M-75 1:4:8 

2.) M-10 1:3:6 

3.) M-15 1:2:4 

4.) M-20 1:1-5 :3 

5.) M-25 1:1:2 3. 

Notes:- C:S:A° C-- Cement, S---Sand, 

A--- Aggregate

3) MINIMUM CLEAR COVER: 

As per IS Code 456:2000

a} Footing = 40mm

b} Column = 50 mm 

c} Slab & stairs = 15 mm 

d} Beam  = 25 mm 

4.) DENSITY 

i} R.C.C = 2500 kg/m³

ii} Steel - 7850 kg/m³ 

iii} Brick = 1600 - 1920 kg/m³ 

iv} PCC= 2400 kg/m³ 

v} Cement = 1440 kg/m³