Question

uestion 1 Consider the portal frames of Figure 1 having unequal beam and columns, and carrying horizontal and vertical loads, a) Find all possible "simple" and "combined" collapse mechanisms for the considered external loads. Make sure that you draw the plastic hinges at the correct location. b) Find the collapse load Pc corresponding to the various mechanisms you have identified. c) Which of the collapse mechanisms you have found in a) is the "true" one? Why? l/2 l/2 2W 2P W B 300 kNm 2M 100kNm 100kNm 0.61 Figure 1 Answers "true" collapse load Pc- 5Mu/L corresponding to a "combined" "true" collapse load wc= 37.5kN corresponding to a sway mechanism mechanism

Answer 1

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