Question

Towers for support of the electric lines are made of wood (as-grown or laminated), steel or aluminum (either lattice structures or tubular poles), concrete, and occasionally reinforced plastics. What would you choose, and what constraints would you think must be met to select the best material?

and what formulas should be used to choose the best material?

Answer 1

First of all,wood is not a regular choice for high tension lines.High tension high voltage lines are needed to be placed at a good height.But wood post above 30 metres height are not common.Also it's not eco friendly to cut down trees to make electric towers.However they are used for low voltage applications in some areas.

Concrete towers are also not widely used.They are expensive and more difficukt to install and to do maintenance.They are used for transmstrans below 30kv

Aluminium and steel are best choices.They are more easier to manufacturer and less expensice and can be installed easy as different units and then connect them together.

Lattice towers are better than tubular ones.Steel lattices have less cost of manufacturing but higher installation cost.But aluminium laticesl are more cost to manufacture but less ecpwnsive to install.

Constraints to be met are low thermal expansion,High strength and elasticity,good physical and chemical stabilitust during extreme weather conditions,ablitiy to withstand sudden shocks and vubratvib forces etc

The formulas are selected according to these constraints.