A simply supported beam has a span of 12 m. The beam carries a total uniformly distributed load of 21.5 kN/m. 1. To prevent excessive deflection, a support is added at midspan. Calculate the resulting moment (kN·m) at the added support.
2. Calculate the resulting maximum positive moment (kN·m) when a support is added at midspan.
3. Calculate the reaction (kN) at the added support.
A 12-m pole is fixed at its base and is subjected to uniform lateral load of 600 N/m. The pole is made-up of hollow steel tube 273 mm in outside diameter and 9 mm thick.
1. Calculate the maximum shear stress (MPa).
2. Calculate the maximum tensile stress (MPa).
3. Calculate the force (kN) required at the free end to restrain the displacement.
A beam 100 mm × 150 mm carrying a uniformly distributed load of 300 N/m rests on three supports spaced 3 m apart as shown below. The length x is so calculated in order that the reactions at all supports shall be the same.
A temporary earth retaining wall consists of wooden plank driven vertically into the ground. The wall is designed to resist 2.4 m height of soil.
Cross-sectional dimensions of the plank = 300 mm wide × 75 mm thick
Allowable bending stress of the plank = 10.4 MPa
Allowable shear stress of the plank = 0.8 MPa
Unit weight of retained soil = 17.3 kN/m3
Active earth pressure coefficient = 1/3
1. Calculate the maximum flexural stress.
A. 12.7 MPa
C. 8.6 MPa
B. 14.2 MPa
D. 10.1 MPa
2. Calculate the maximum shear stress.
A. 1.11 MPa
C. 0.99 MPa
B. 0.33 MPa
D. 0.77 MPa
3. Calculate the minimum thickness of the plank to prevent failure.