Page 54 - Civil Engineering Formulas
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CASE 4.  Beam Supported Both Ends—Three Unequal Concentrated Loads, Unequally Distributed









                    M 1 = Ra 1 – W (a 1 – a)  W 1  + W = R or > R  W 1  + W 2  = R 1  or > R 1  b 2  W 2  R 1  M 1  M 2




                M = Ra   M 2  = Ra 2  – W (a 2  – a) – W 1  (a 2  – a 1 ) M (max) = M when W = R or > R  M (max) = M 2 when W 2 = R 1 or > R 1  L  b 1  W 1 b



              x: when x = a  x: when x = a 1  x: when x = a 2  M (max) = M 1  when  a 2  a 1  W  a  x




              At  At  At                       R     M     V



              Wb + W 1 b 1  + W 2 b 2  L  Wa + W 1 a 1  + W 2 a 2  L  V = R – W  V = R – W – W 1








               R =  R 1 =  V (max) = Maximum reaction  x: when x > a and < a 1  At  x: when x > a 1  and < a 2  At  (Continued) FIGURE 2.2












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