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STRUTS AND TIES

 An understanding of the terms, ‘struts, and ‘ties’ is important, as these can be mentioned in examinations. All structures have forces acting on them. You should have an understanding of tensile, compressive and shear forces (see previous sheet). The part of the structure that has a tensile force acting on it is called a TIE and the part that has a compressive force acting on it is called a STRUT. WALL The beam is held in position by a steel rod. The weight of the beam is stretching the rod (tensile force). ROOF The roof beams are under pressure from the weight of the tiles on the roof (compressive force). The floor beam is being stretched (tensile force). FLAGPOLE The wires on either side of the flagpole are being stretched (tensile force). Why is the pole under a compressive force ?    In the diagram opposite, forces act across the entire length of the beam (it bends because of the weight of the person). When a structure bends like this, it is in tension, as it is being stretched. 1. Draw an example of a structure and identify which part(s) are in tension and which are in compression. 2. Explain the difference between tension and compression. CLICK HERE FOR STRUCTURES INDEX CLICK HERE FOR FORCES INDEX Web www.technologystudent.com