Because steel is stronger than wood.
But I'm not sure steel is stronger than metal, but steel is a metal and a pretty tough one.
The primary building materials in cable-stayed bridges are steel, which is used in the cables and also as the reinforcing material in the concrete, which is the other primary building material.
I dont know i need the same answer buddy!
Caleb and Thomas Pratt invented the truss bridge in 1844. Some of the materials that have been used in truss bridges are timber, steel, reinforced concrete, and iron.
civil engineers, structural engineers, and architects are the main bridge builders.
The exact year the truss bridge was invented is not known. Early forms of truss bridges were seen as earl as 1820 and iron truss bridges did not appear until 1850.
The Romans used the arch to build large buildings and bridges.
iron is used to make bridges (i think)
The problem with iron bridges was that the material was not as reliable as carbon steel, so it was replaced starting in the late 1800s and was completely unavailable for bridge building by the early 1900s. Bridges in the late 1700s were made of cast iron, but, by the early 1800s, cast iron gave way to wrought iron.
Iron is used in construction due to its strength and durability. In bridges, iron is often used because it can support heavy loads and provide stability. In houses, iron is commonly used in structural elements like beams and columns to provide strength and support to the building.
Iron is not used to build houses, but iron is used in other things because it is strong.
iron is used to make bridges (i think)
iron ore
Stone bridges were built to get over rivers etc, before iron or steel was used.
Steel
Heavier Angle iron is often used as a structural element in building and bridges, while lighter angle iron is used for a variety of supports such as an adjustable bed frame. Pound for pound angle is more rigid than standard pipe.
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