Bolted angles to form lightweight, long-span trusses Image courtesy of Metsec plc.
In light roof trusses, entirely bolted connections are less favoured than welded connections due to the requirement for gusset plates and their increased fabrication costs. This type of truss is used where gravity loads are predominant see below left. Trusses From Steelconstruction.
The full use of this advantage is achievable if the height of the truss is not limited by criteria other than the structural efficiency, e. Vierendeel trusses have rigid joints which must transfer significant bending moments, especially near the supports. This article focuses on typical single storey industrial buildings , where trusses are widely used to serve two main functions:.
In this type of truss, diagonal members are alternatively in tension and in compression. A truss is essentially a triangulated system of usually straight interconnected structural elements; it is sometimes also referred to as an open web girder.
Two types of general arrangement of the structure of a typical single storey building are shown in the figure below. Plus, the roof has more resistance too because of that. Trusses generally give an economic solution for spans over 20 m.
Hollow sections are typically connected by welding whilst open sections are connected by bolting or welding , which will usually involve the use of gusset plates.
You can use it for industrial buildings, but this truss also works for drawing rooms and in general those spaces that are very large. This method is one of the oldest, as well as most economical ones that you can find on the market, as it allows you to bring in proper ventilation.
An alternative Pratt truss is shown below right where the diagonal members are in tension for uplift loads. Where bolted connections are used, it is necessary to evaluate the consequences of 'slack' in connections.
Nodes will generally be welded in the workshop. The Queen Post Truss is designed to be a very reliable, simple and versatile type of roof truss that you can use at any given time.
Lateral restraint of the upper chord is generally given by the purlins and the transverse roof wind girder.