Page 364 - Aircraft Stuctures for Engineering Student

Problems 345

Problems

P.9.1 Figure P.9.1 shows the section of an angle purlin. A bending moment of
3000 N m is applied to the purlin in a plane at an angle of 30" to the vertical y axis.
If the sense of the bending moment is such that its components My and M,. both
produce tension in the positive xy quadrant, calculate the maximum direct stress in
the purlin stating clearly the point at which it acts.
Ans. oz,max -63.3 N/mm' at C.
=
. Y4

/ / ALL
E
E / IO mm

Fig. P.9.1

P.9.2 A uniform thin-walled beam ABD of open cross-section (Fig. P.9.2) is
simply supported at points B and D with its web vertical. It carries a downward
vertical force W at the end A in the plane of the web.

't

't

I
C

41 15

Fig. P.9.2