1. UNIT 3. STRUCTURES AND FORCES<br />A STRUCTURE<br />WHAT’S IT?<br />A set of elements that can bear burdens<br />Without breaking them <br />Without being deformated too much<br />FUNCTIONSHold loads <br />Limit a space<br />Protect a space<br />TYPES<br />146055683250146802865381centertop<br />TRIANGULATED STRUCTURE<br />There is a type of Frame Structure.<br />Constituted by bars that are united to form triangles<br />TRIANGULATION They are light and very resistant<br /> An example of triangulation: a crane.<br />Triangles are seen around us especially in the construction industry in building structures.<br />They can be large or small<br />They can be permanent or temporary<br />Look these examples:<br /> <br />Now, pay attention to the triangles of each structure<br /> <br />EXAMPLE: A house<br />The roof is a triangle.<br />The walls are constructed and then structural roof timbers are set in position.<br />Exercise<br />Why?<br />A triangle is a very strong shape.<br />Rain water runs off the roof down the drainpipes, away from the house.<br />-3651254692653. FORCES<br />2159000257175TENSION: A pulling force that will try to stretch or lengthen.<br />1872946284042COMPRESSION: a pushing force that tries to squash or shorten.<br />847228255629<br />BENDING: Forces try to cause bending or deformations<br />SHEAR: Sliding forces that act in opposite directions.<br />TORSION: Forces cause twisting<br />847090108585<br />