Sample Question Paper for 9210-111Graduate/Post Graduate Diploma in Civil EngineeringStructural analysis

Duration: three hours

You should have the following for this examination• one answer book• non-programmable calculator• pen, pencil, drawinginstruments

• Design codes: The code ofpractice “BS 5950: part 1:2000

The following data areattached• Standard beam displacements• Fixed end moments

General instructions• This paper consists of seven questions over three sections.• Answer five questions with only one question from Section C.• A non-programmable electronic calculator may be used but candidates must showsufficient steps to justify their answers.• Drawings should be clear, in good proportion and in pencil. Do not use red ink.• All questions carry equal marks. The maximum marks for each section within aquestion are shown.

Section A – Elastic analysis

1 A continuous beam (ABCD) carries loads and is supported as shown in Figure Q1. Use the slope deflection method to analyse this beam. a) Calculate the support moments and draw the support moment diagram. (10 marks)b) Draw the bending moment diagram for the beam. (5 marks)c) Draw the shear force diagram for the beam. (5 marks)

Figure Q1

2 A frame (ABCD) carries loads and is supported as shown in Figure Q2. Use the moment distribution method to analyse this frame. a) Calculate the support and joint moments at A, B, C, and D. (10 marks)b) Draw the bending moment diagram for the frame. (5 marks)c) Draw the shear force diagram for the frame. (5 marks)

Figure Q2

2

3 Two cantilever beams AB and CD are connected at their free ends using a vertical spring of stiffness 12EI/L3. Flexural rigidities of beams are given in the Figure Q3.a) Determine the force in the spring using the stiffness method of analysis. b) Calculate the end translations of the cantilevers. (20 marks)Hint: you may consider only the bending deformations of the cantilevers.

Figure Q3

3 See next page

Section B – Plastic analysis

4 a) Explain the need for the yield line analysis method in structural analysis. (4 marks)b) A square (3.0 m × 3.0 m) isotropic reinforced concrete slab is simply supported

along all four edges and subjected to a uniformly distributed load (Figure Q4). It has been proposed to use the yield line analysis method to analyse this slab.i) If the effective depth of the slab is 0.12 m, and equal amounts of reinforcement

are provided in both directions (X, Y) which have thefollowing properties:As = 314 mm2/m, fcu= 30 N/mm2, fy= 460 N/mm2, determine the yield moment in both the X and Y directions (m).Clearly state the assumptions that you have made in this analysis. (6 marks)

ii) Draw the yield line pattern at collapse. (4 marks)iii) Determine the collapse load of the slab. (6 marks)

Figure Q4

5 A continuous beam (ABCD) is subjected to the loading system as shown in Figure Q5.It has been proposed to use the plastic theory of collapse to analyse this beam. The plastic moment resistance capacity and flexural rigidity of the beam are Mp and EI respectively.a) Determine the independent collapse mechanisms of the beam. (6 marks)b) Determine the collapse load of possible collapse mechanisms and hence

determine the global collapse load of the beam. (6 marks)c) Draw the bending moment diagram at collapse. (8 marks)

Figure Q5

4

Section C – Basic design

[The use of code of practice ‘BS 5950: part 1: 2000’ for design in simple and continuousconstruction: hot rolled section will be allowed for this section]

6 a) Giving examples, briefly explain the following load types.i) Dead loads.ii) Live loads.iii) Dynamic loads. (3 marks)

b) What is meant by ‘redundancy’ in structural analysis? (3 marks)c) Discuss the advantages and disadvantages of having redundancies in structures. (3 marks)d) Clearly explain the reasons for using different overall load factor (�f ) when

calculating ultimate limit state loading. (3 marks)e) Briefly explain what is meant by ‘limit state design’ in the design of steel structures. (3 marks)f) In the design of a multi-storey building structure, one structural engineer has

recommended the use of steel sections compared to reinforced concrete. Identify some of the attributes required for a multi-storey building structure and list the advantages of using steel as a construction material. (5 marks)

5 See next page

7 a) Briefly explain the advantages of designing buildings as statically indeterminate rather than statically determinate. (3 marks)

b) The roof of a building is flat, 18.0 m wide and supported by steel trusses at 4.0 m centres. These trusses are made of steel square hollow sections (SHS) carrying roof purlins at 3.0 m centres as shown in Figures Q7a and Q7b. The total dead load of the roof covering (including purlins) is 1.25 kN/m2 and live load on the roof is 1.5 kN/m2. i) Analyse the truss using joint resolution for factored loading in accordance

with BS 5950. (10 marks)ii) Select suitable square hollow sections for the top chord and bottom chord

members in the truss in accordance with BS 5950. (7 marks) N.B: You can refer to Table Q7 for the extracted Table 3 of BS 4848: Part 2:1991:

‘Specifications for hot-finished hollow sections’ for section properties.

Figure Q7a

Figure Q7b

6

Tab

le Q

7: T

able

3 o

f BS

4848

: Par

t 2:1

991:

‘Sp

ecif

icat

ion

s fo

r h

ot-

fin

ish

ed h

ollo

w s

ecti

on

s’ fo

r se

ctio

n p

rop

erti

es.

7

Data Attachments

CITY & GUILDS 9210-111

CITY & GUILDS 9210-111

JULY SERIES 2013

D

DISPLACEMENTS OF PRISMATIC MEMBERS

The following table gives the displacement in beams of constant flexural rigidity EI and constant torsional rigidity GJ, subjected to the loading shown on each beam. The displacement (translations & rotations) directions are shown in the diagrams. The deformation due to shearing forces are neglected.

f1 f5 f2 f3 f4

l/4 l/4 l/4 l/4

Beam

5384

192048

Displacement

f5 f3

q per unit length

f4 f2

f1

l/4 l/4 l/4 l/4

11768

f5 f3 f4 f2

f1

l/4 l/4 l/4 l/4

P

f5 f3 f4 f1

f2

l/4 l/4 l/4 l/4

P

M

Beam Displacement

f1

T

(E ect of warping ignored) l

P

f3

f2

f1

l/2 l/2

f3

f2

f1

l/2l/2

q per unit length

f3

f2

f1

l/2 l/2

M

Data Attachments

CITY & GUILDS 9210-111