Marks 1
A beam is undergoing pure bending as shown in the figure. The stress (๐)-strain (๐) curve for the material is also given. The yield stress of the material is ๐๐. Which of the option(s) given represent(s) the bending stress distribution at cross-section AA after plastic yielding?


Marks 2

It is given that $$P = 1$$ $$N,$$ $$L = 1$$ $$m$$ and Youngโs modulus $$E = 200$$ $$GP$$a. The cross-section is a square with dimension $$100$$ $$mm$$. The bending stress (in Pa) at the point A located at the top surface of the beam at a distance of $$1.5L$$ from the left end is _____________ .
(Indicate compressive stress by a negative sign and tensile stress by a positive sign).
What is the maximum value of bending stress?
What is the maximum value of bending moment?

The maximum magnitude of bending stress (in MPa) is given by
The maximum bending moment occurs at
Permissible tensile stress for steel = 156.8 N/mm2
Permissible tensile stress for steel = 14.89 N/mm2
Young's modulus of mild steel = 1.96 $$ \times $$ 105 N/mm2
Young's modulus of wood = 0.117 $$ \times $$ 105 N/mm2