Talk:Shear centre

2007-03-2 Automated pywikipediabot message
--CopyToWiktionaryBot 05:43, 2 March 2007 (UTC) Consider the figure below showing a cantilever beam with a transverse force at the tip. Under the action of this load, the beam may twist as it bends. It is the line of action of the lateral force that is responsible for this bend-twist coupling. If the line of action of the force passes through the Shear Center of the beam section, then the beam will only bend without any twist. Otherwise, twist will accompany bending.

The shear center is in fact the centroid of the internal shear force system. Depending on the beam's cross-sectional shape along its length, the location of shear center may vary from section to section. A line connecting all the shear centers is called the elastic axis of the beam. When a beam is under the action of a more general lateral load system, then to prevent the beam from twisting, the load must be centered along the elastic axis of the beam.

The two following points facilitate the determination of the shear center location.

1. The shear center always falls on a cross-sectional axis of symmetry. 2. If the cross section contains two axes of symmetry, then the shear center is located at their intersection. Notice that this is the only case where shear center and centroid coincide.


 * A zee section does not have two axes of symmetry, but does have a shear center and a centroid that coincide. This is due to radial symmetry of the section. It is still appropriate to say that if a section has two axes of symmetry, the shear center will be located at the controid. However, this is not the only case.Jebix (talk) 12:37, 16 October 2008 (UTC)