Disc (technical mechanics)
In technical mechanics, a disk is the model of a surface structure that is flat in the reference state and is loaded by forces in its plane . Bending moments whose axes lie in the plane of the pane and forces that act perpendicular to the pane are not taken into account. (An ideal pane remains flat even when it is deformed.)
A plate is also considered to be a flat component in technical mechanics, but it is loaded with precisely those forces and moments that are neglected when considering the component as a disk .
In the construction technology of a flat member is diaphragm action awarded when it is able to receive the attacking in the direction of its plane forces and safely dissipate without going through the resulting internal shear stresses being excessively deformed or destroyed.
Real panel-shaped components in construction always combine the properties of an ideal pane with those of an ideal panel ; with the following special features:
- Shells are curved or arched surface structures,
- Membranes can be viewed as a special case of a disk . Since they do not offer any resistance to compressive forces and bending moments, however, they have no disc effect .
Practical examples of discs
- Wall-like carriers and wall panels in the field of construction . To stiffen a structure, at least three wall panels are required, which are located in different planes that are not parallel to each otheror at an acute angle. If two wall panels in parallel planes, the wall panels need to rigidly formed or a fourth wall element to be added.
- Ceiling panes in the field of construction. Monolithic ceilings (e.g. made of in-situ concrete ) are easily considered to be sufficiently resilient panes, while precast ceilings and, in particular, wooden beam ceilings require special measures to achieve a pane effect.