Question

A beam whose cross-section is shown in the figure is subjected to a bending moment M inclined at 0 = 70° from the z axis. a) Locate the orientation of the neutral axis B and draw this axis on the figure b) Calculate the maximum flexural tensile stress Omax,T and the maximum flexural compressive stress Omax.c in the beam and indicate at which points in the section these occur. M= 2 Nm D e Z 20 mm A B 60 mm

Answer 1

y Question: z 20mm А. 60mm B solo o = 70° M= 2 N-m My = 2 sm 70 1.88 Nm Mr = 2 costo 0.685 N-m. - Mz y Iz + My z Iy . 3 X 10-12 2 4x10 8 -12 X 10 Iy - Izz 60 x 20 12 20 x 60 12 stresses at each at A., YA = 36 X108 comer. -0.04 ZA= 0.03 TA 0.685 X (-0.01) + 1.88 X 10.03) 368108 4X108

classes Butterflow Date Page Цв — O o 3 Оe - Г. Ч24 MP4 ар дь з — Т. о| 00 - — О. О. - D'ol) 36x ( Х — O'o3 + 1.00 ЧXIь в Оe - — 1, 39 D MP4 ЦЕС О. о 1 7 - -0.63 0 - - 0, 680 О-о! ) 3. xo-8 tl: 80 Чxts -p: 03) V/1 Хафи 02 — 1:424 MP4 at D Әр O•o/ 7 - 0:03 бр — 6 68 S (ool) + 180 o o3 3.xing Что бо . 1.39 MPa 1. 424 MP4 mad) I maa) c = о А - 1 ч 2 4 MP4. at С

Butterflow simply CIAS Date Page neutral axis 1.429 2 1.39 0.06 - 2 - 1.4292 t 0.0857= 1.392 z = 0.0304 ( from A) A 1.89 +1:429 17.39| 11.4291 N