Solved: 2. The steel frame ABCD lies in the horizontal (xz) plane, with AB and

Question

2. The steel frame ABCD lies in the horizontal (xz) plane, with AB and CD parallel to x-axis and BC parallel to z-axis. One end of the frame (A) is fixed to a rigid wall and the other end (D) is subjected to a force F = 120 N in the -y direction. a) Use conservation of energy (work done by force F = strain energy stored in the structure) to determine the vertical (y) deflection at D. b) Use Castigliano's second theorem to determine the rotation at D about the z-axis. B 다 D F AB = CD = 1.5 m. BC = 1.2 m. Bending and torsional rigidities of segments AB, BC and CD are equal with EI = 1.4 x 103 Nm² and GJ = 1.1 x 10' Nm². Consider only strain energy due to bending and torsion. Note: each member in this structure will experience bending in only one plane, which can occur alongside torsion. The strain energies due to bending and torsion can be calculated separately and added to get the total strain energy of a member that is experiencing both.