Question

Learning Goal: Part A - Force with a known deflection To solve for forces in statically indeterminate bars with axial loads. When the number of reaction forces is greater than the number of equilibrium equations, the system is slatically indeterminate. Solving for the reactions requires some additional equations. These additional equations come from considering compatibility relationships (.e., continuity of displacements and relationships between displacements and loads). For an axially loaded member, the compatibility relationship for the deflections can be written by setting the total relative axial displacement between the ends of the member to a known value. NL The square bar shown (Figure 1) is 65 mm thick and 6 m long and is fixed supported at both ends. A load directed loftward is applied at point C, as shown, L2 = 3.75 m from the left end. The modulus of elasticity is E = 100 GPa . If point C moves 8 = 0.150 mm to the left, what is the applied force? Express your answer with appropriate units to three significant figures. View Available Hint(s) HA c ? The load-displacement relationship 8 = AE gives another = Value Units equation for the deflections. Once the internal normal force of each segment is written in terms of the end reactions and applied loads, there is enough information to solve for the reactions. Submit Part B - Reaction with a known load Figure Consider a new structure, where the thickness of the bar is reduced to 32.5 mm from C to B (it is still square) (Figure 2) and <= 3.75 m. If the applied load Is F-370 kN, then what is the reaction at A? Let a positive reaction act to the right. The total length is still 6 m Express your answer with appropriate units to three significant figures. View Available Hint(a) 1 of 2 A с B T. THẢ ? -L2 Value Units

Answer 1