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Why Are Steel Ceiling Beams And Frames I-Shaped?




Buying a steel framed building is about buying a modular, easy-to-construct, robust and hard-wearing structure that can be used for temporary or permanent purposes, and at its core is a very efficient design.


Besides the corrugated steel to improve the building’s structural stability, its primary frame is made up of I-shaped steel beams, also known as universal beams.


The wide flanges and narrow web are distinctive construction elements, but there is a very good reason why the beams are designed in this way and it starts with the mathematician Jacob Bernoulli.


Structural beams have been a fundamental part of construction for as long as wood has been used, but until the 18th century, there was no real mechanism for understanding why beams carry the loads they do and what causes a beam to deflect.


Galileo Galilei and Leonardo da Vinci tried, but whilst both made attempts to create a working theory, neither had enough information to complete it or were caught up in assumptions that turned out to be wrong.


Jacob Bernoulli (1655-1705) made the first set of discoveries, whilst his son Daniel alongside Leonhard Euler would help to complete the theory around 1750.


However, it would take another century of development and exploration of the theory before the most efficient type of beam based on the Euler-Bernoulli beam theory would be constructed.


Basically, by removing all but the top and bottom of the beam, the frame is very capable of handling bending and shear loads, which makes it perfect for structural components which need to efficiently carry a lot of weight.


This is one of the big engineering discoveries that made the skyscraper possible, and requires far less metal than a solid beam would, allowing for much more affordable construction and easier transportation, savings that are ultimately passed to the customer.

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