Thrust flow
In construction , technical mechanics and strength theory, the shear flow is the course of the shear forces from transverse forces or torsional moments in the cross section of a component . It has the unit of measurement N / m ( Newtons per meter), i.e. H. Force per length.
The resulting sum of the shear flows gives the vector of the shear forces Q in terms of magnitude and direction :
with the running coordinate s, which is related to the center of gravity of the cross-sectional area .
Thin-walled components
In the case of thin-walled components ( profiles ), the shear stress distribution and thus also the shear flow can be assumed to be constant over the component thickness :
In this case the shear flow runs parallel to the component edge.
The shear flow at the profile centerline is:
In addition:
With:
- the static moment
- the area moment of inertia .
The thrust flow is constant in a thin-walled, closed cross-section that is subjected to torsion . This can be calculated from the torsional moment using Bredt's first formula .
Individual evidence
- ↑ Russel C. Hibbeler: Technische Mechanik 2 Strength Theory , 8th Edition, Pearson Germany, Munich 2013, ISBN 978-3-86894-126-5 .