General

Question 1

What is the hierarchy of stiffnesses in stability calculations?

Answer 1

Axial
Bending
Torsional

Question 2

Why are end fixings important for long beams?

Answer 2

Bolt slippage can cause large deflection in longer beams

Question 3

How are wind loads applied to a structural model?

Answer 3

As points on beam-column connections which represent the area around that point

Question 4

What size of bolts are required for moment connections?

Answer 4

8.8

Question 5

Why is there no k in PC1 & PC2 for prestressed concrete?

Answer 5

There are no losses at transfer

Question 6

Which inequalities bound the profile of bowed reinforcement bars?

Answer 6

PC1 & PC4

Question 7

What is the stiffness at the upper end of a column which is attached to two beams either side (bl & br) and a column above (cu)?

Answer 7

Ku = (Kc + Kcu)/(Kc + Kcu + Kbl + Kbr)

Question 8

How does a plate girder bear loads?

Answer 8

Top flange takes compression moment
Web takes shear
Bottom flange takes tension moment

Question 9

What are the limits of depth to web thickness ratio for plate girders?

Answer 9

100-250

Question 10

How is a prestressed concrete beam analysed and what does this mean?

Answer 10

Serviceability limit state so no factors are used

Question 11

What is the minimum limit for steel stress at the bottom of a composite beam?

Answer 11

165N/mm2

Question 12

What must you remember when finding the stress in the top of the concrete?

Answer 12

Convert values back from steel to concrete

Question 13

What must you do for a composite beam question?

Answer 13

Draw a diagram of all forces and lever arms

Question 14

What is the limit for c in a plate girder?

Answer 14

Epsilon x flange thickness where epsilon is in the Eurocodes

Question 15

What is depth d of a plate girder?

Answer 15

Height y - flange thickness

Question 16

What must always be done for point loads on a plate girder?

Answer 16

Stiffeners are positioned under them

Question 17

What is a in plate girder stiffener calculations?

Answer 17

Spacing between stiffeners

Question 18

What is the approximation for the moment at the end and centre of a rigid portal beam?

Answer 18

M= wL2/16

Question 19

What diagrams must be drawn in a rigid steel portal frame question?

Answer 19

A full dimensioned frame and a section of the bays with half of the columns above and below

Question 20

If there is a wind load of 28kN per floor on a 6 storey building (including ground floor and roof), what is the total?

Answer 20

0 x 14 + 4 x 28 + 1 x 14 = 126kN

Question 21

What is the short term concrete conversion factor for a composite section?

Answer 21

E of steel / E of concrete

Question 22

What is the long-term concrete conversion factor of a composite section?

Answer 22

2 * E of steel / E of concrete

Question 23

What must be found to compute the elastic stresses for short term and long term in a composite section?

Answer 23

The second moment of Area (I) for both short and long term

Question 24

What moment is used to calculate the short-term elastic stresses?

Answer 24

Live load only

Question 25

What moment is used to calculate the long-term elastic stresses?

Answer 25

Sum of dead load and self weight

Question 26

In principle, what is the equation for elastic stress?

Answer 26

(Moment x distance of outermost fibre to n/a) / (second moment of area)
Divided by conversion factor if concrete

Question 27

How do you determine the horizontal load on the mid height of wind loaded columns above a target floor?

Answer 27

Total wind load above target floor / number of half-beams
Inner columns have larger values to match the total wind load

Question 28

How do you determine the horizontal load on the mid height of wind loaded columns below a target floor?

Answer 28

Total wind load above and including target floor / number of half-beams
Inner columns have larger values to match the total wind load

Question 29

How does a rigid frame structure resist wind moment?

Answer 29

A force of
Total wind moment / width of frame base
Is carried in both outer columns, one upward, one downward

Question 30

How is effective length of a column in a rigid steel frame determined

Answer 30

A chart gives the fraction Le/L from upper and lower limits of column stiffness

Question 31

What is the lower limit for column stiffness if the base is fixed?

Answer 31

0.5

Question 32

What is Wply of a plate girder?

Answer 32

Wply = Med/fy

Question 33

How can you estimate the flange area for a plate girder?

Answer 33

Af = Med/(y * fy)