STRUCTURES

STRUCTURES

1. DEFINITION

   • Set of relationships that the parts of a whole maintain among themselves.

2. TYPES

   • Massive structures
   • Superficial structures
   • Vaulted structures
   • Frame structures
   • Triangulated structures
   • Hanging structures

3. FORCES

   • Fixed or permanent
     • always present and the structure will always support the force at all times. For example: the weight of a building, body of a trunk.
   • Variables or intermitent
     • appear or disappear depending on external conditions to the structure. For example: the action of the wind, snow.
   • Static forces
     • the variation of the intensity, place or direction in which strength doesn ́t change in short periods of time. For example: the weight of a building, snow.
   • Dynamic forces
     • the forces acting on the structure suddenly change value, place of application or direction. For example: earthquakes, sudden impacts.

4. Fighting resistance: the structures

   • Natural
     • have been "made" by nature thousands of years ago by evolution.
       • Examples: skeleton, shell of a crustacean, trunk and branches of a tree.
   • Artificial
     • are created by human beings.
       • Examples: beams of a building, a table, a bridge, a crane.

5. CONDITIONS

   • Stability
     • An object is much more stable the closer the center of gravity is to the ground and the larger the base, the more stable the object will be.
   • Strength or resistance
     • A structure is resistant when it is capable of enduring, or supporting, the efforts to which it is subject.
     • Tension or traction (to stretch) • Compression (to compress or smash) • Bending or flexibility (to curve or bend) • Torsion (to twist) • Shear (to cut)
   • Rigidity
     • To achieve the rigidity of a structure (which is not deformed), the profiles must form triangular cells. Cables, bars and braces can be used for this purpose.