This is an anticipated lateral pressure from wind, but may also be a downward pressure or an uplift force on the roof plates. Describes the forces of sudden impact. Forces are determined by their magnitude, direction, and point of application. A. Forces may be in tension, compression, shear, or turning. Tension is a force to stretch a beam in one direction.
Compression is a force that presses on a beam in one direction.
Shear is the tendency of loads to deform or fracture a member by sliding one section against another. Turning moment is a force that produces motion around a point or an axis. Non concurrent forces create turning moments. Non concurrent forces may create deformation, or raking in timbers when the beam itself is presented with compressive and tension forces. The strength of materials and the forces that buildings are typically designed to resist are described in modern code compliance books.