# horizontal shear stress

## Notching on Beams

NSCP 2001
When rectangular shaped girders, beams or joists are notched at points of supports on the tension side, the horizontal shear stress at such point shall not exceed:

$F_v = \dfrac{3V}{2bd'}\left( \dfrac{d}{d'} \right)$

Where

$d$ = total depth of beam
$d'$ = actual depth of beam at notch

When girder, beams or joists with circular cross section are notched at points of support on the tension side, the actual shear stress at such point shall not exceed:

## Bending Stress and Shearing Stress in Timber Beam

 Bending Stress $f_b = \dfrac{M}{S} = \dfrac{Mc}{I}$   Horizontal Shear Stress $f_v = \dfrac{VQ}{Ib}$ For Rectangular Sections $f_b = \dfrac{6M}{bd^2}$   $f_v = \dfrac{3V}{2bd}$