A Find The Minimum Weight Design For The Portal Frame Figure 1 Under The Given Arrangement Of Collapse Ultimate Lo 1 (76.83 KiB) Viewed 42 times
A Find The Minimum Weight Design For The Portal Frame Figure 1 Under The Given Arrangement Of Collapse Ultimate Lo 2 (77.56 KiB) Viewed 42 times
(a) Find the minimum-weight design for the portal frame (Figure 1) under the given arrangement of collapse (ultimate) load. [15] Assume both columns have the same capacity (Mc). Adopt a linear relationship between section mass and plastic moment capacity. Use a linear weight function. X = LiMc + L2MB + L3Mc 100 kN 3 m 3 m + 3 m Figure 1 (b) Suppose that the frame must be designed to sustain another load arrangement (i.e. load case) as shown in Figure 2. Find the minimum-weight design for the portal frame which satisfies both load cases (as shown Figures 1 and 2). Use the same weight function given in part (a). [15] 250 kN 11³m 3 m 6 m 3 m 50 kN 50 kN Mc Mc M₂ 3 m M₂ 3 m 3 m Mc Mc
(c) Use the list of UB sections provided in Table 1 to determine the practical minimum-weight design of the portal frame having constant section (Mc = Mb). The design must satisfy both load cases (Figures 1 & 2). [5] Table 1. Universal Beam (UB) sections Designation Mass per metre Zpl Mp h*b*m kg/m 10^6mm^4 kNm 203x133x25 25.1 259 91.9 203x133x30 30 313 111.1 254x146x31 31.1 395 140.2 254x146x37 37 485 172.2 254x146x43 43 568 201.6 305x102x25 24.8 336 119.3 305x102x28 28.2 408 144.8 305x102x33 32.8 481 170.8 305x165x40 40.3 626 222.2 305x165x46 46.1 722 256.3 305x165x54 54 843 299.3 356x171x45 45 773 274.4 356x171x51 895 317.7 356x171x57 1010 358.6 356x171x67 1210 429.6 51 57 67.1
Join a community of subject matter experts. Register for FREE to view solutions, replies, and use search function. Request answer by replying!