Truss is a metal (sometimes wooden) structure whose constituent members are connected triangles, and this set of triangles acts as a single object. The task of the truss is to evenly distribute the weight, control tension and compression without bending or shearing. Geometrically, triangles are more stable compared to quadrilaterals or polygons, because in order to avoid cutting, the corners of these quadrilaterals or polygons must be fixed somewhere. As mentioned earlier, the truss is made up of triangular units and these triangular units consist of straight and uncurved members. The ends of these straight and unbent members are connected to each other in connections called knots
Types of metal trusses:
Simple metal truss A simple truss is a type of planar truss that starts with a triangular element and can be expanded by adding two straight members without curvature as well as a joint (node). This type of truss may be used in the construction of a framed roof consisting of sloping beams and a roof joist. The use of this type of truss is very common in old buildings, but nowadays, due to the presence of more formal types (spatial, composite), this type of truss system is used less
Flat metal truss (plate) A planar truss is a truss in which all members are located in a two-dimensional plane. This type of truss, which has parallel lower and upper members, is usually used in series (back to back). Flat truss is used in the construction of roofs, bridges, beams and even other mechanical structures such as bicycles and airplanes. Space metal truss Unlike a flat truss that lies on a two-dimensional plane, a space truss is actually a three-dimensional grid of connected triangles. Space trusses are particularly popular among employers; Because they are very resistant and they are usually used in the construction of the roof of exhibitions, swimming pools and factories
Composite metal truss Composite truss is obtained by combining two or more simple metal trusses. The endurance and resistance of this type of truss is much higher compared to other types of trusses. For this reason, this type of truss system is used in many construction projects. It should be noted that the type of truss system can be different for each project and its type should be selected according to the needs and goals of the project Advantages of metal trusses Resistant to external forces such as earthquakes Simple and fast installation and implementation Easy to move and transport (compared to concrete structures) Economically very affordable Ideal for high buildings
