Engineers TV's video: CPEC Bridge Girder Animation

Please watch: "Peshawar BRT new Updates" https://www.youtube.com/watch?v=GulUT2uoli4 --~-- A girder bridge is perhaps the most common and most basic bridge. A log across a creek is an example of a girder bridge in its simplest form. In modern steel girder bridges, the two most common girders are I-beam girders and box-girders. If we look at the cross section of an I-beam girder we can immediately understand why it is called an Ibeam (illustration .) The cross section of the girder takes the shape of the capital letter I. The vertical plate in the middle is known as the web, and the top and bottom plates are referred to as flanges. To explain why the I shape is an efficient shape for a girder is a long and difficult task so we won't attempt that here.