Page 74 - Civil Engineering Formulas
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R
          aL  nP
            1  2            P          n(n + 2)  n + 1
         P                                           (5n 2  + 10n + 6)  (n + 1) 3
       L  2  R =              L  2         (For n an  even number)
          aL                           PL  8
                          P                             (For n an even number)
         P
      W = np  aL      P                              n(n + 2)  (For n an odd number)
         P     L  Load      Shear      Moment  c  L         Elastic curve  (f)
          aL          P
         P                                           PL 3  384EI
       L  2  aL  nP  P        L  2
         P                      maL                  odd number)
             1  2                       (n + 1)(For n an  5n 2  + 10n + 1  n + l
          aL  R =
           1  n + 1   R           m(n – m + 1)  n + 1  PL  8  n(n + 2)  n + 1  PL 3  384EI
            a =                   PL  2          PL 2  24EI



                          P
             R = P
         kL
                                                      k(3 – 4k 2 ) Elastic-curve equations for prismatic beams: (d) Shears, moments, and deflections for a concentrated load at midspan of a simply supported
                                           L′′  2
       P                                                  k(3x′ – 3x′ 2 – k 2 )
         (1 – 2k)L  L  Load  Shear  PkL  Moment       PL 3  24EI  Elastic curve  (e) prismatic beam. (e) Shears, moments, and deflections for two equal concentrated loads on a simply supported prismatic beam. (f) Shears, moments, and deflec-


       P                                                 PL 3  6EI
                                           L  2  x(3k – 3k 2 – x 2 )
         kL                                         k(1 – k)  x′  (k < x′ < (1 – k))
             R = P             xL  (x < k)  PxL
                                              PL 3  6EI  PL 2  2EI
                       P


                              P/2                                    tions for several equal loads equally spaced on a simply supported prismatic beam. (Continued)
                 P
                1  2
                 R =
            L  2
                                                        PL 3  48EI

                   L  Load        Shear  PL  4  Moment  c  L  Elastic curve
           P                                                  (d)
                                                x(3 – 4x 2 )
            L  2
                 P                   xL 1  2
                1  2                   x <  xPL
                 R =                    1  2    PL 3  48EI  PL 2  16EI  FIGURE 2.3
                           P/2


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