(Solved):   A rectangular cross section beam \( \mathrm{b}=80 \mathrm{~mm} \) wide and \( \mathrm{d}=1 ...

 

A rectangular cross section beam \( \mathrm{b}=80 \mathrm{~mm} \) wide and \( \mathrm{d}=120 \mathrm{~mm} \) deep is subjected to a maximum shear force \( \mathrm{V}=20 \mathrm{kN} \). If the maximum shear stress occur at the neutral axis, plot the shear stress distribution diagram due to shear forces only. To draw the shear stresses diagram, calculate only two shear stress values: - at \( 20 \mathrm{~mm} \) from the top and, - at the neutral axis. The following formulae may be used: \[ \tau=\frac{\mathbf{V A} \overline{\mathbf{y}}}{\mathbf{I b}} \text { where: } \] - V= maximum shear force. - \( A= \) cross sectional area considered. - \( \bar{y}= \) distance to the neutral axis from the centroid of the area considered, - I= second moment of the cross-section area about its centroid and \( b= \) the width of the beam.