**Thanks for Visiting**

**Thanks for Visiting**

Unit weight means weight of material per unit volume(1 m^{3 }or 1m x 1m x 1m ).

Unit weight of cement : **14.40 KN/m ^{3}**

Unit weight of Sand :**17 KN/m ^{3}**

Unit weight of Aggregate :**15 KN/m ^{3}**

Unit weight of Brick Masonry :**19.20 KN/m ^{3}**

Unit weight of Brick Stone :**20.80 to 27 KN/m ^{3}**

Unit weight of Steel :**78.50 KN/m ^{3}**

Unit weight of Wood :**12 KN/m ^{3}**

Unit weight of Plain Cement Concrete : **24 KN/m ^{3}**

Unit weight of R.C.C : **25 KN/m ^{3}**

Unit weight of Water : **10 KN/m ^{3}**

**Thanks For Visiting**

A spring is a device whose function is to deflect under tensile or compressive load and recover its original shape when unloaded.

Types of Springs:

- Helical Spring
- Spiral Spring
- Leaf Spring

**Helical Springs: **In this a wire coiled in the form of helix.

- Closed Coil Helical Spring(Tension Spring)
- Open Coiled Helical Spring(Compression Spring)
- Torsional Spring

Closed Coil Helical Spring |
Open Coiled Helical Spring |

1. Resist tensile forces. | Resist Compressive forces |

2. Pitch is very small. | Pitch is high |

3. Each turn lie in same plane at right angles to the axis of helix. | No turn lie in the same plane , hence each turn lie inclined to the axis of helix. |

The maximum shear stress occurs at the innermost fibres of a helical spring under torsion is because of curvature effect.

Where, D= mean diameter of helical coil

d= diameter of spring wire.

**Brick defects are as follows:- **

**bloating**: presence of swollen mass at surface due to excess in carbonaceous and sulphur content.**lamination**: presence of lamina due to air entrapment in clay, when molded clay and sand mixed with another mold then two layers were formed with entrapped air.**Chuffs**: A deformed shape was obtained by falling of rainwater on hot brick.**Black core :**due to improper burning i.e. lack of oxygen for carbon and sulphur oxidation within clay.**porosity :**presence of voids i.e small empty pockets.**nodules:**a small swelling at the surface of brick.

** Thanks for Visiting**

Copyright © 2017 www.engineeringspine.com. All Rights Reserved. Sitemap