Sulphur and Zinc

Zinc and tin

Phosphorous and Tin

Iron and Carbon

Reusable

Fire and corrosion resistance

High strength per unit mass

High durability

$450 \frac{\mathrm{Kg}}{{\mathrm{m}}^3}$

$625 \frac{\mathrm{Kg}}{{\mathrm{m}}^3}$

$7850 \frac{\mathrm{Kg}}{{\mathrm{m}}^3}$

$500 \frac{\mathrm{Kg}}{{\mathrm{m}}^3}$

0.1

1.0

0.3

2.0

Structure should be aesthetically pleasing but structurally unsafe

Structure should be cheap in cost even though it may be structurally unsafe

Structure should be structurally safe but less durable

Structure should be adequately safe, should have adequate serviceability

It refers to condition when structure is not usable

It refers to services offered in the structure

It means that the structure should perform satisfactorily under different loads, without discomfort to user

It means that structure should be economically viable

Determination of cost of structure

Determination of axial forces, bending moment, shear force etc.

Determination of factor of safety

Drafting architectural plans and drawings

Limit State Method

Working Stress Method

Ultimate Load Method

Earthquake Load Method

Limit State Method

Working Stress Method

Ultimate Load Method

Earthquake Load Method

Permissible Stress = Yield Stress x Factor of Safety

Permissible Stress = Yield Stress / Factor of Safety

Yield Stress = Permissible Stress / Factor of Safety

Permissible Stress = Yield Stress – Factor of Safety