Description of pre engineered building system

Pre-engineered buildings are factory-built buildings of steel that are shipped to site and bolted together.What distinguishes them from other buildings is that the contractor also designs the building,a practice called design&build.This style of construction is ideally suited to industrial buildings and warehouse;It is cheap,very fast to erect,and can also be dismantled and moved to another site,more on that later.These structures are sometimes called‘metal boxes’or ‘tin sheds”by laymen.They are essentially rectangular boxes enclosed in a skin of corrugated metal sheeting.
The structural system of pre-engineered building give it its speed and flexibility.This system consist of factory-fabricated and factory-painted steel column and beam segments that are simply bolted together on site.

The columns and beams are custom-fabricated I-section members that have an end plate with holes for bolting at both ends.These are made by cutting steel plates of the desired thickness,and welding them together to make I sections.
The cutting and welding is done by industrial robots for speed and accuracy;operators will simply feed a CAD drawing of the beams into the machines,and they do the rest.This production line style of work makes for great speed and consistency in fabrication.

The sharp of the beams can be tailored to optimunm structural efficiency:they are deeper where the forces are greater,and shallow where they are not.This is one form of construction in which the structures are designed to carry exactly the loads envisioned,and no more.

Where Pre-engineered building are used?
Pre-engineered building is most often used in：
1.High rise buildings Because of its strength,low weight,and speed of construction.
2.Industrial buildings because of its ability to create large span spaces at low cost.
3.Warehouse buildings for the same reason.
4.Residential buildings in a technique called light gauge steel construction.
5.Temporary structures as these are quick to set up and remove.