written 6.1 years ago by | modified 5.0 years ago by |
A beam 8.5 m long rest on the supports 5 m apart, the beam carries load as shown in fig. Draw the SFD and BMD showing all the important points.
written 6.1 years ago by | modified 5.0 years ago by |
A beam 8.5 m long rest on the supports 5 m apart, the beam carries load as shown in fig. Draw the SFD and BMD showing all the important points.
written 6.0 years ago by | • modified 6.0 years ago |
$\sum F_Y = 0 (+ve)$
$V_A+V_B = 40+60+50*5 = 350$ (1)
$\sum M_B = 0 (+ve)$
$-40*(1.5+5)+V_A*5-50*5*\frac{5}{2}+60*2 = 0$
$V_A = 153 KN$ (2)
$V_B = 197KN$ from (1) and (2)
Shear force analysis:--
Shear force at $C = -40KN$
Shear force at any section CA, ie just before pt A
Shear force at A = -40KN and just after point A = $-40+V_A = -40+153 = 113KN$
Shear force at D = 60KN
Shear force just on RHS of $B = 60-197 = -137KN$
Finding the value of 'x' where bending moment is maximum, for that equating shear force equation to zero.
Let the section be 'x' meters from C
$-40+153-50x = 0$
x = 2.26m
Bending moment analysis:
BM at C = 0, BM at D = 0
BM at $A = -40*1.5 = 60KNm$
BM at $B = -60*2 = -120KNm$
$BM_x$ is maximum at distant x = 2.26m from C
$BM_x = 40*2.26+153*(2.26-1.5)-50\frac{(2.26-1.5)^2}{2} = 11.44KNm$