Page 11 - Mechanics of Structures – Chapter 1

Mechanics of Civil Engineering Structures – Chapter 5

Solution
. .
Shear Stress Equation, τ = .

Where,

1. S = Shear force = = 5 (5) = 12,500 N
2 2
⃐
2. To determine from base and Ixx , since sketch is symmetrical

ℎ 200
⃐
= = = 100 mm
2 2 3 3 3 3
3. To determine Ixx = Second moment of area = - = (200)(200) - (175)(150)
12 12 12 12
= (133.33 x 10 ) – (49.22 x 10 )
6
6
4
6
= 84.11 x 10 mm

Consider section as shown in sketch

τ1 – At top most fibre

τ1 τ2 – Connection of flange and web passing through
flange
τ2
τ3 τ3 – Connection of flange and web passing through web

τ4 τ4 – At Neutral axis
τ5 – At connection passing through web
τ5
τ6 τ6 – At connection passing through flange
τ7 τ7 – Bottom most fibre

Notes :

τ1 = τ7 = 0

τ2 = τ6

τ3 = τ5

τ4 = τmax

NHO JKA PSAS Page 11