STRUCTURAL MATERIAL(Aluminum,mansory and timber)

Aluminum

*Aluminum is used whenever light weight combined with strength is an important factor.
Those properties, along with its resistance to corrosion have made it the material of choice for airplane structures, light roof framing.
*Aluminum members can be connected by riveting, bolting and to a lesser extent by welding. *Aluminum has a modulus of elasticity equal to 10,000 ksi (about three times lower than steel), a coefficient of thermal expansion of 2.4 × 10−5 and a density of 173 lbs/ft3.
The ultimate strength of pure aluminum is low (13,000 psi) but with the addition of alloys it can go up. 1Stirrups which are used as vertical reinforcement to resist shear usually have a yield stress of only 40 ksi.
Density of normal weight concrete is 145 lbs/ft3 and 100 lbs/ft3 for lightweight concrete. *Coefficient of thermal expansion is 0.65 × 10−5 /deg F for normal weight concrete. 32 When concrete is poured (or rather placed), the free water not needed for the hydration
process evaporates over a period of time and the concrete will shrink.This shrinkage is about 0.05% after one year (strain). Thus if the concrete is restrained, then cracking will occur3.
*Concrete will also deform with time due to the applied load, this is called creep. This should
be taken into consideration when computing the deflections (which can be up to three times the instantaneous elastic deflection).
MASONRY

Masonry consists of either natural materials, such as stones, or of manufactured products such as bricks and concrete blocks,stacked and bonded together with mortar.with low tensile resistance.
hydrated lime.
As for concrete, all modern structural masonry blocks are essentially compression members The mortar used is a mixture of sand, masonry cement, and either Portland cement

Timber
 Timber is one of the earliest construction materials, and one of the few natural materials with good tensile properties.
The properties of timber vary greatly, and the strength is time dependent.Timber is a good shock absorber (many wood structures in Japan have resisted repeated earthquakes)hemlock and larch.
The most commonly used species of timber in construction are Douglas fir, southern pine, Members can be laminated together under good quality control, and flexural strengths as
high as 2,500 psi can be achieved.