CE408 Lecture Notes - Lecture 3: Stopping Sight Distance, National Safety Council, Mental Chronometry

A simply supported beam having a span l =3.6m is to carry a uniformly distributed load of
intensity w = 1600kg/m. The cross-section is to be rectangular with depth h and width b = h/2. If
the allowable bending stress in tension or compression is σ w = 84 kg/cm 2 . What is the required
depth h for the cross-section?

Which of the following statements is correct about stress in engineering?

1. The SI unit of stress is Newton

2. It is the internal force expressed per unit area of a body

3. The normal stress is coplanar with the area of cross-section 

4. None of these

A wood beam 1.8 m long is simply supported at its ends, has a cross-section 15cm wide by 60cm deep and carries a uniformly distributed load of intensity w = 8000 kg/m over the full span. Calculate the bending stress at a point 20cm above the bottom of the beam and 60cm from the left support & also find out the maximum bending stress for this beam.