Basic statements 14

Question 1

Buckling is an example of structural instability

Answer 1

True

Question 2

When an elastic structure is in equilibrium, its potential energy has its maximum

Answer 2

False - Minimum

Question 3

Plastic buckling can be used in smart designs of structural energy absorption

Answer 3

True

Question 4

Initial deflections of a column do not affect buckling behavior or stability conditions for the column

Answer 4

False

Question 5

Semi-empirical formulas can be used to estimate the critical stress in a column. Such relations implicitly take into account e.g. elasto-plastic material behavior and initial distortions

Answer 5

True

Question 6

Principle of virtual work: the potential energy is the sum of potential energies for the internal and external forces acting on a body/system

Answer 6

True

Question 7

A column that is loaded by axial and lateral loads has lesser margin to buckling collapse compared with a column subjected to only axial loads.

Answer 7

True

Question 8

Stable equilibrium is achieved if and only if the potential energy PI os positive definite

Answer 8

True

Question 9

The Johnson-Ostenfeld correction takes into account the effect of plasticity into the elastic buckling strength

Answer 9

True

Question 10

For short bars, with open thin-walled sections, where the torsional rigidity is low, failure may occur as pure twisting or by a combination of bending and twisting.

Answer 10

True

Question 11

Tripping is defined as the state where the stiffeners rotate about the line of attachment to the plating

Answer 11

True