Basic Statements 4

Question 1

Engineering beam thery assumes that plane sections should remain plane after bending

Answer 1

True - Bernoulli and Naviers theory

Question 2

For thin-walled structures subjected to pure bending. the shear stress distribution through the thickness is non-uniform

Answer 2

False - its linear with maximum on the edges and a zero value in the middle

Question 3

The static moment is an area moment around a given axis

Answer 3

True -

S = integral [lever*dA]

Question 4

The shear stress distribution (linear or parabolic) in a given cross-section is governed by the formulation of the static moment

Answer 4

True -

Tau = SzVy/(Iztmax) for example

Question 5

If external loads are applied in the shear centre of a beam cross-section, there will be pure bending

Answer 5

True - Pure bending will only occur if and only if a force is applied in the SC. Otherwise there will be torsion.

Question 6

The shear centre is always in the geometrical centre of gravity for a cross-section

Answer 6

False - Nope. It could be outside the open cross-section as well as inside

Question 7

For open/single symmetric cross-sections, the shear centre may be located outside the cross-section profile

Answer 7

True - Otherwise we will see the beam be affected by torsion

Question 8

To determine the shear centre, we make use of the fact that the shear forces Vy and Vz must be staticaly equivalent to the shear stresses acting on the cross-section

Answer 8

True -

Vye = Flever arm for example