Determine the direct stress at the base of the hollow circular chimney of height 20 m with external diameter 4 m and internal diameter 2 m. The chimney is subjected to a horizontal wind pressure of intensity 1 kN/m2, and specific weight of the material of chimney is 20 kN/m3.
1
400 kN/m2
2
250 kN/m2
3
300 kN/m2
4
350 kN/m2