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FIGURE 2.2 (Continued)CASE 4. Beam Supported Both Ends—Three Unequal Concentrated Loads, Unequally DistributedR =Wb + W 1 b 1 + W 2 b 2
LR 1 =V (max) = Maximum reactionAtx: when x > a and < a 1Atx: when x = aAtx: when x = a 1M = RaM 1 = Ra 1 – W (a 1 – a)
Atx: when x = a 2
M 2 = Ra 2 – W (a 2 – a) – W 1 (a 2 – a 1 )
M (max) = M when W = R or > RM (max) = M 1 whenM (max) = M 2 when W 2 = R 1 or > R 1L
a 2W W 1 W 2RMVxR 1M 1
M 2b 2
b 1
a bW 1 + W = R or > RAtx: when x > a 1 and < a (^2) W 1 + W 2 = R 1 or > R 1
V = R – W
V = R – W – W 1
Wa + W 1 a 1 + W 2 a 2
L
a 1