Page 76 - Civil Engineering Formulas
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(L + L′) 2  (L 2  – L′ 2 )  x′ 2  (4L′ 2  – L 3 + 3L′ 3 )
           w         x′L′  wL′x′    wL′ 2  2
          L′   w  2L       w  2L
                R 2 =       R 2  (L + L′) 2 (L – L′) 2  wL′  24EI
                        wL′         wL′ 2  2

                (L 2  – L′ 2 )  R 1 = wLx  w  8L 2  L′ 2  L 2  Elastic curve  (i)
          L       Load        Shear         Moment  L 2  (1 – 2x 2 + x 2 ) –2L′ 2 (1  – x 2 )
           w   w  2L        1 – L′ 2  L 2  1 –  L
                R 1 =  xL  L  2

                        R 1        (L 2  – L′ 2  – xL 2 )  wL 2 x  24EI
                                  wx  2


                    P               P
                                                    PL 3  3EI
                                                 (2 – 3x + x 3 ) Elastic-curve equations for prismatic beams: (g) Shears, moments, and deflections for a concentrated load on a beam overhang. (h) Shears,

                                        xL
                           Load              Moment            moments, and deflections for a concentrated load on the end of a prismatic cantilever. (i) Shears, moments, and deflections for a uniform load over the full
                     L                Shear     PL 3  3EI  Elastic curve  (h)
                                           PxL
                         R = P

                       PL           R       PL


                                                 (L + L′)
                                                PL′ 2  3EI
                            P
               P                                     2(L + L′) – L′x′ (1 + x′)
                                   x′L′
                      L′
                                       Px′L′
                                        PL′
                   P        R 2                   x(1 – x 2 )   length of a beam with overhang. (Continued)
                   L + L′  L  Load  Shear  xPL′     PL′ 2 (1 – x′)  6EI  Elastic curve  (g)
                   R 2  =  L                     PL′L 2  6EI
                                   xL
                   P  L                  Moment  L  3  PL′L 2      3EI
                   R 1 = L′                       9          FIGURE 2.3

                               R 1               d max  =

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