Worked examples to EC3 quiz

Please answer the following 10 multiple choice questions, then click 'submit' to check the result. The pass mark for a CPD certificate is 8 out of 10, and you may retake the quiz as many times as you wish, but the questions will vary! Please note that one, two, three or all of the possible answers presented for each question may be right, and to gain a mark for that question all correct answers must be identified.

Good luck

Worked examples to EC3

In flexural buckling, what non-dimensional slenderness is approximately equivalent to a slenderness L/ryy = 160?

1.0
2.0
3.0
4.0

If a web is Class 2 and a flange is Class 1, what Class is the section?

There must be some mistake - both elements should be the same Class
Class 1
Class 2
Class 3

Which partial factor should be used when calculating buckling resistance?

γM0
γM1
γM2
It depends on the mode of buckling

Where does a designer find values of C1 for different shapes of bending moment diagram?

In BS EN 1993-1-1
In the UK National Annex to BS EN 1993-1-1
In NCCI
In an appendix to BS EN 1993-1-1

Having calculated the non-dimensional slenderness, how might the reduction factor, χ, be determined?

Using the expressions given in EN 1993
Using the figure given in EN 1993
Using look-up tables in NCCI
Using look-up tables in EN 1993

When is the factor αLT used?

When calculating flexural buckling resistance
When calculating lateral-torsional buckling resistance
When classifying webs subject to axial load and bending
When calculating torsional buckling resistance

Which bending modulus should be used with a Class 2 section?

Elastic modulus
Plastic Modulus
Effective Modulus
Young's Modulus

Which class of sections use the Gross Area, A when calculating the resistance?

Class 1
Class 2
Class 3
Class 4

How is ε calculated?

No need - its given in the tables
ε = (235/fy)1/2
ε = (275/fy)1/2
ε = (355/fy)1/2

Why does torsional-flexural buckling not apply to UKC sections?

It does, but it's never critical
Because UKC sections have a high torsional rigidity
Because the flanges are relatively thick
Because UKC sections are not asymmetric