|Science Focus Topic 4 Notes: Forces, Loads and Stresses||| Print ||
External forces on structures are stresses that act on a structure from outside the structure.
These forces produce internal forces, or stresses, within the materials from which the structure is made. These
internal stresses can change the shape or size of a structure and is called deformation. This deformation can lead to repair of the damage to the structure, or failure of the structure.
A dead load is a permanent force, acting on a structure.
This includes the weight of the structure itself.
A live load is a changing, or non-permanent force acting on a structure.
This includes the force of the wind and the weight of things that are in or on a structure.
Impact forces (things that collide with the structure) are another type of live load.
A bending force is a combination of tension and compression
Shear and torsion forces are also a combination of tension and compression
Resisting Stress - The Inside View
Strength of materials can be traced to the forces between the tiniest particles of the materials.
(See. Figure 4.39 p. 314)
Topic 4 Review Page 314