For so the design of beam , we will always choose the larger shear force to find the larger shear stress ?PhanthomJay said:
The formula for calculating shear stress in a beam is:
Shear Stress = (VQ)/(It), where V is the shear force, Q is the first moment of area of the beam, I is the moment of inertia of the beam, and t is the thickness of the beam.
The shear force in a beam can be determined by summing up all the external forces acting on the beam in the specific section being analyzed. This can also be done by drawing a shear force diagram.
The first moment of area of a beam is a measure of the distribution of cross-sectional area of the beam about a given axis. It is calculated by multiplying the area of each section of the beam with its distance from the chosen axis.
The thickness of a beam has a direct effect on the shear stress. As the thickness increases, the shear stress also increases. This is because a thicker beam has a larger area for the shear force to act on, resulting in a higher shear stress.
The units for shear stress in the beam formula are typically in pascals (Pa) or newtons per square meter (N/m2). However, depending on the system of units used, it can also be expressed in psi (pounds per square inch) or kips per square inch (ksi).
