Question

The beam shown in the figure below (Figure 1) is made of elastic perfectly plastic material for which σY = 395 MPa .

100 mm 100 mm 100 mm 100 mm 100 mm 100 mm

A)Determine the maximum elastic moment that can be applied to the cross section.

Express your answer to three significant figures and include appropriate units.

B)Determine the maximum elastic moment that can be applied to the cross section.

Express your answer to three significant figures and include appropriate units.

Answer 1

The section is symmetric about both axis. so, ca will be a Contre. * - + -- 160 - i. 100 ci@ Yc = 300 – 180 mm 100 100 101 Let us Consider section as dotted lines. square it is section as numbered shown in as o & the sections @ corners are Numbered A =- 300 * 300 = 9oooo mm 4 @ Az = 100 x 100 = 4 @ 10000 mm IX - Ixx, - [Txx2 + A₂ (4-7) J x 4 Y = 1 50 mm from bottom

..Tax = 30% - + 1dbo w (isa-sw}]xy = 675000 000 - 433,333,333.33 - 241666 666.7 mm 9 given, dy – 395 N/mm² we w tooы know м - 7 y = farthest point from c. M - 241666666.7 x 395 150 - 636,388,888.9 namm - 636.389 knom Max elastic moment = 636.389 kN-m.