Q. A cantilever beam of span 2 m carries three point loads of 2 kN, 1 kN and 1 kN at a distances of 0.3 m. 1.2 m and 2 m respectively from fixed end. Draw S.F and B.M diagrams and find maz, bending moment and indicate where it occurs.
Total load on the beam = 2 + 1 + 1 + 4 KN S.F.D: (SHEAR FORCE DIAGRAM)
S.F at A = 4kN
SFat C = 4 – 2 = 2kN(just right of C)
SF at C = 4kN (just left D)
SF at D = 2 – 1 = 1kN(just right of D)
SF at D = 2kN (just left of D)
SF at B = 2 – 1 = 1kN (just left of B)
SF at B = 0kN (just right of B)
Max. S.F occurs at A = 4kN B.M.D: ( BENDING MOMENT DIAGRAM)
M{B} = 0
M{C} = – 1 * 1.7 – 1 * 0.9
= – 1.7 – 0.9 = – 2.6kNm
M{D} = – 1 * 0.8 = – 0.8kNm
M{A} = – 1 * 2 – 1 * 1.2 – 2 * 0.3
= – 2 – 1.2 – 0.6
= – 3.8kNm
.. Max. B.M occurs at support A i.e., at fixed end
=M A =M max =-3.8 kNm
M max =3.8 kNm(Hogging)
