Advanced Methods of Structural Analysis

446 12 Plastic Behavior of Structures

ab

M N

P

Δ

Fig. P12.2

Ans.PlimD2yA.

12.3.Symmetrical structure is subjected to loadPas shown in Fig.P12.3.The
cross sectional area of the vertical member isA, and for rest members arekA,where
kis any number. Yielding stress for all members isy. Perform the elastic analysis
and calculatePallow. Calculate the limit load and determine ratioPlim=Pallow.Use
the static method.

a

A

kA a

P

1

Fig. P12.3

Ans.PlimDyA.1C2kcos ̨/.

12.4.Absolutely rigid rod is suspended by vertical hangers as shown in Fig.P12.4.
The axial stiffness of all membersEAis constant. The limit internal force for each
element isNy. Find the limit loadPfor each design diagram.

P

d

l

dd

142 3

d

Fig. P12.4

Ans.PD1:33Ny

12.5.A concentrated forcePacts on the uniform pinned-clamped beam as shown
in Fig.P12.5. The limit moment isMy. Determine the limit loadPlim.