Page 77 - Handbook of Civil Engineering Calculations, Second Edition
P. 77

1.60            STRUCTURAL STEEL ENGINEERING AND DESIGN

                            7. Compute the horizontal displacement of one point
                            relative to another
                            Thus, EI  2   EI	 B a   Pb(ac   ab/2).
                            8. Combine the computed displacements to obtain the absolute
                            displacement
                                                               2
                                                                                        2
                            Thus EI   EI(  2   EI  1 )   Pb(ac   ab/2   c /2);    [Pb/(2EI)](2ac   ab   c ).
                                        Statically Indeterminate Structures

                            A structure is said to be statically determinate if its reactions and internal forces may be eval-
                            uated by applying solely the equations of equilibrium and statically indeterminate if such is
                            not the case. The analysis of an indeterminate structure is performed by combining the equa-
                            tions of equilibrium with the known characteristics of the deformation of the structure.



                            SHEAR AND BENDING MOMENT OF A BEAM
                            ON A YIELDING SUPPORT

                                                                                 2
                                                               9
                            The beam in Fig. 41a has an EI value of 35   10 lb·sq.in. (100,429 kN·m ) and bears on
                            a spring at B that has a constant of 100 kips/in (175,126.8 kN/m); i.e., a force of 100 kips
                            (444.8 kN) will compress the spring 1 in. (25.4 mm). Neglecting the weight of the mem-
                            ber, construct the shear and bending-moment diagrams.






























                           FIGURE 41
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