92b5352f-6b74-4e84-a953-ef93eb08786a

7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

1/24

Chartered Membership Examination A

Chartered Membership Examination

Thursday 28 April 2011

Structural Engineering Design and Practice

09.30 13.00 and 13.30 17.00 (Discussion

between individuals is not permitted during lunch

period). A period o teen minutes is provided orreading the question paper, immediately beore the

commencement o the examination. Candidates are

not permitted to write in answer sheets, or on

drawing paper or to use a calculator during this time.

Candidates must satisy the Examiners in ONE

question.

Important

The written answer to the question selected and any

A3 drawings must bear the candidates number and

the question number at the bottom o the page. Only

the answer sheets supplied by the Institution maybe used. The candidates name should not appear

anywhere in the script.

Notes to Candidates

1. TO PASS THE EXAMINATION,

CANDIDATES MUST SATISFY THE

EXAMINERS IN BOTH PARTS OF THE

QUESTION ATTEMPTED.

2. Examiners will only mark work written by hand

during the examination.

3. A air proportion o marks will be awarded orthe demonstration o an understanding o

undamental engineering concepts, as distinct

rom calculation o member orces and sizes.

NOTE: In the calculation part o all questions,

establishing orm and size is taken to mean

compliance with all relevant design criteria, i.e.

bending, shear, defection, etc.

4. In all questions 50 marks are allocated to Section

1 and 50 marks to Section 2.

5. The Examiners are looking or sound structural

designs. It should also be remembered that

aesthetics, economy and unction are important

in any competent engineering scheme.

6. Any assumptions made and the design data and

criteria adopted must be stated.

7. Portable computers or programmable calculators

may be used but sucient calculations must be

submitted to substantiate the design, and these

should be set out as in practice.

8. Good clear drawings and sketches are required;

they should show all salient and structural

eatures to suitable scales and should

incorporate adequate details.

9. Candidates will not be allowed to include any

previously prepared calculations, notes,

sketches, diagrams, computer output or other

similar material in their answer sheets or A3

drawings. Any previously prepared inormation

submitted by candidates will be ignored by the

examiners.

10. Strictly no external electronic contact is allowed

between a candidate and anyone outside the

examination venue. Mobile phones must be

switched o throughout the duration o the

examination.

11. This paper is set in Imperial Units.

Now read Reminder on page 3.

7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

2/24

2 Chartered Membership Examination

7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

3/24

Chartered Membership Examination 3

Chartered Membership Examination,

a reminder rom your Examiners

The work you are about to start has many eatures

in common with other examinations which you have

tackled successully but it also has some which areunusual.

As in every examination you must ollow careully the

NOTES FOR CANDIDATES set out or your guidance

on the ront cover o this paper; allocate the available

time sensibly and set out your work in a logical and

clear way.

The unusual requirement o the examination is that

you demonstrate the validity o the training and

experience that you have acquired in recent years.

The Institution must be satised that you are able to

bring all the various skills you are expected topossess to the eective solution o structural design

problems whether or not the problem is presented

in terms that are within your actual experience.

Chartered Structural Engineers must have the ability

to design and a acility to communicate their design

intentions. Where you are required to list and discuss

possible structural solutions you must show by brie,

clear, logical and systematic presentation that you

understood the general structural engineering

principles involved.

In selecting and developing your design you should

also remember the guidance given in the

Institutions report, Aims o Structural Design, and in

particular:

(1) the structure must be sae,

(2) a good design has certain typical eatures

simplicity, unity and necessity,

(3) the structure must ull its intended unction.

I you have diculty in deciding the correct

interpretation o a question, pay particular attention to

point 6. notes to candidates, on the ront cover. The

examiners will take into account your interpretation and the design you base on this i this is clearly

stated at the beginning o your answer.

7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

4/24


7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

5/24


Question 1. Theatre

Clients Requirements

1. A new theatre and arts complex is to be built in a city centre: see Fig. Q1. The theatre is to be located below ground level

with practice acilities, oce space and eating acilities above.2. A clear space must be provided within the perormance area o the theatre bounded by gridlines 1 and 3 and gridlines B

and C. No permanent structure may be provided in this space. At either end o the theatre space there is a service zone

where there are no structural restrictions. Access or maintenance must be provided to all parts o each zone.

3. Above the theatre is an internal/external dining space at elevation 0 0. The architect has specied that the only

structural elements permissible on grid line 2 between gridlines B and C are slender columns. No bracing or walls are

permitted.

4. A double storey rehearsal studio is at elevation 14 9. The area available or rehearsal shall be maximised by limiting

columns to a minimum. Two foors o oces are located above the rehearsal space where there are no specic restrictions

on structure.

5. The architect wants to allow as much light as possible into the building on Gridline 2 and has stipulated that more than

70% o the elevation shall be glazed between gridlines B and C.

Imposed Loading

6. Roo 30ps

Floor loading Ground and theatre foors 200ps

Elevated foors 100ps

Loadings include an allowance or partitions, nishes, services and ceilings.

Site Conditions

7. The site is level and located next to a busy road. Excavations may not approach the road closer than 3 3.

Basic wind speed is 90mph based on a 3 second gust; the equivalent mean hourly wind speed is 45mph.

8. Ground conditions The site is level and the single borehole at the centre o the building is representative o

the whole site. Ground water was ound at -13 0

Borehole 1 Ground 9 9 Made ground

9 9 26 3 Sti clay. C = 1600ps

Below 263

Rock. Allowable bearing pressure = 8tons/t2

Omit rom consideration

9. Detailed design o stairs.

SECTION 1 (50 marks)

a. Prepare a design appraisal with appropriate sketches indicating two distinct and viable solutions or the

proposed structure. Indicate clearly the unctional raming, load transer and stability aspects o each

scheme. Identiy the solution you recommend, giving reasons or your choice. (40 marks)

b. Ater the design has been completed, the client advises that the rehearsal studio is to be column ree

internally. Write a letter to the client explaining what impact there will be on the design and how this might

be achieved. (10 marks)

SECTION 2 (50 marks)For the solution recommended in Section 1(a):

c. Prepare sucient design calculations to establish the orm and size o all the principal structural elements

including the oundations. (20 marks)

d. Prepare general arrangement plans, sections and elevations to show the dimensions, layout and

disposition o the structural elements and critical details or estimating purposes. (20 marks)

e. Prepare a detailed method statement or the sae construction o the building and an outline construction

programme, including details o any temporary propping o the structure required above ground level

during construction. (10 marks)

7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

6/24


7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

7/24


Question 2. Exhibition Centre


1. A two-storey building to house a new exhibition: see Fig Q2. The exterior walls are to be o brickwork and the

roo is to be clad with concrete tiles.

2. Each foor consists o a rectangular space 60 0 long by 60 0 wide. The clear foor to ceiling height o each

foor is to be 13 0. No structural members are permitted within these spaces.

3. There is to be a hole between the foors at the centre o each foor 20 0 long by 40 0 wide. No structural

members are permitted in this hole.

4. There are no restrictions on the structural depth o each foor or on the structure outside the foor space.

5. An existing pedestrian subway 10 0 wide runs under the ull length o the proposed building. The base o the

sub-way is 10 0 below ground level. No additional loads must be imposed on the roo or walls o this subway.

6. Access to the upper foor is via an independent link not structurally connected to the Exhibition Centre.

Imposed Loading

7. Roo loading 10ps

Floor loading 100ps

Site Conditions

8. The site is located in a town centre. Basic wind speed is 102mph based on a 3 second gust; the equivalent mean

hourly wind speed is 51mph.

9. Borehole 1

Ground level 1 6 Top soil

1 6 19 6 Sti clay C = 3000ps

No water was ound

Borehole 2 Ground level 1 6 Top soil

1 6 9 9 Sti clay C = 3000ps

Below 9 9 Rock allowable sae bearing pressure 5tons/t

No water was ound


10. Detailed design o staircases or lit shats





b. Ater your design is complete, the client explains that he does not want a roo over the hole in the centre

o the building. Write a letter to your client advising him o the implications o this change. (10 marks)


For the solution recommended in Section 1(a):






programme. (10 marks)

7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

8/24


7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

9/24


Question 3. Farm Access Bridge


1. A private access bridge across a canal rom a newly built road along the canal embankment to arm land on

the opposite side. See Fig. Q3.

2. Transverse cross all can be ignored. Navigational clearance as shown in Fig.Q3 must be maintained at all times.

Unobstructed views along the canal are required rom the bridge.

3. Because o an existing underground gas main, no new temporary or permanent works are permitted within 9 9

o the canal on the arm land side. The existing concrete canal walls can be used or support and have a maximum

sae vertical working load capacity o 3 tons/t.

4. The road and canal may not be closed or more than one weekend over a period o six months.

Imposed Loading

5. Farm vehicle load 26tons as detailed in Fig.Q3.

Uniormly distributed load 100ps

The above loads do not occur simultaneously.

Site Conditions6. The site is located in open countryside. Basic wind speed is 102mph based on a 3 second gust; the equivalent

mean hourly wind speed is 51mph.

7. Ground conditions:

Road embankment Granular ll, N=15

Farmland Clay, C=800ps

Sandstone Allowable bearing capacity 10tons/t2

No groundwater was encountered during ground investigation works.


8. Longitudinal imposed loading.



bridge including its oundations. Indicate clearly the unctional raming, load transer and stability aspects

o each scheme. Identiy the solution you recommend, giving reasons or your choice. (40 marks)

b. During design the client inorms you that the water level in the canal can sometimes rise to 12 below

the top o the canal wall. Write a letter to the client advising him o the implications. (10 marks)






e. Prepare a detailed method statement or the sae construction o the bridge and an outline constructionprogramme. (10 marks)

7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

10/24


7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

11/24


Question 4. Hotel Building


1. A six-storey hotel with a basement in a town centre, see Figure Q4.

2. Lits and staircases are to be located at the rear corners o the building as shown in Fig. Q4. Floor to foordimensions are to be 14 9 or the basement and levels 1 and 2, and 11 6 or levels 3 to 6.

3. The foor at level 2 is to be set back rom the ront o the building to provide an atrium, and a 12 0 wide

balcony is to be provided at this level as shown in Fig. Q4.

4. The ront elevation o the building is to be glazed to provide maximum lighting to the interior and a 49 3 wide

and 11 6 high door is required to this elevation.

The ront o the building is inclined so that at ground level the aade is set back 16 6 rom the site boundary.

(See section A.)

5. Columns are not permitted in the atrium area. There are no other restrictions on column spacings.

Imposed Loading

6. Roo 50ps

Basement, levels 1 and 2 100ps

Levels 3 to 6 60ps

Site Conditions

7. The site is level and is located in a town centre. Basic wind speed is 102mph based on a 3 second gust;

the equivalent mean hourly wind speed is 51mph.


Ground level to - 16 6 loose and compressible ll

-16 6 to - 33 0 silty sand and gravel N = 6, density = 119 lb/t3, = 35

- 33 0 to - 52 6 dense sands, N varies rom 25 to 50

Below - 52 6 rock allowable bearing capacity 15tons/t2

Groundwater was encountered at - 5 0


9. Detailed design o stair/lit cores.



proposed structure. Indicate clearly the unctional raming, load transer and stability aspects o

each scheme. Identiy the solution you recommend, giving reasons or your choice. (40 marks)

b. Ater receiving your completed design, the client wants to add a second lower basement, with a foor to

ceiling height o 14 9, to the building or use as storage space. Write a letter to your client explaining

the eect o this on your proposed design. (10 marks)



including oundations, superstructure and any signicant retaining structures. (20 marks)





7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

12/24


7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

13/24


Question 5. Town Centre Car Park


1. A new multi-storey car park next to the main street incorporating a shop unit at street level. See Fig. Q5.

2. The site slopes away rom the main street. Vehicular entrance and exit are to be rom the rear o the site.Pedestrian access is required rom both the high street and rom the rear o the site. The pedestrian

access rom the high street should be beside the shop unit. See Fig. Q5.

3. No more than one internal column is permitted in the shop unit.

4. A clear foor to sot height o 9 9 is required to the shop unit and a clear foor to sot height o 7 9 is required

to the car park zones.

5. The top car park level is to be open with a 6 6 high parapet around the perimeter.

6. The number o car parking spaces should be maximised.

7. A minimum re resistance period o 90 minutes is required or structural elements.

Imposed Loading

8. Shop unit 100ps

Car park areas 50ps

Site Conditions

9. The site is located in a coastal area near the sea. Basic wind speed is 90mph based on a 3 second gust; the

equivalent mean hourly wind speed is 45mph.


Borehole 1

Ground level to - 13 0 made ground

-13 0 to - 19 9 sand and gravel N=10

Below - 19 9 sand and gravel N=40

Water encountered at 16 6 below ground level.

Borehole 2

Ground level to - 1 6 made ground

-1 6 to - 9 9 sand and gravel N=10

Below - 9 9 sand and gravel N=40

Water encountered at 6 6 below ground level.


11. Detailed design o the lits and staircases.





b. Ater completion o scheme design, the client inorms you that he wishes to increase the size o the shop

unit by including a second level below the original unit. Write a letter to the client advising on the structural

implications o this change and the eect on car parking capacity. (10 marks)



including oundations. (20 marks)

d. Prepare general arrangement plans, sections and elevations to show the site layout, dimensions, layout

and disposition o the structural elements and critical details or estimating purposes. (20 marks)

e. Prepare a detailed method statement or the sae construction o the car park and an outline construction


7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

14/24


7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

15/24


Question 6 continued overlea

7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

16/24


7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

17/24


Question 6. Lieboat Station Building


1. A building or housing a lieboat and towing tractor at Level 1 with an overhead crane over its length; as

shown in Fig. Q6. At the Northeast corner there is a 3 3 wide staircase up to Level 2. From the pavement on

the east side, a doorway at Level 2 provides access to a lobby, changing rooms and control room leading to a

searont balcony. A 3 3 wide walkway provides access rom Level 2 changing rooms to the lieboat. The south

elevation to the lieboat housing is to be glazed and incorporate an 26 3 high electrically operated roller shutter

door.

2. The building is located in a corner plot 85 3 wide by 85 3 long with an existing retaining wall along the north

and west boundaries and a public access road on the east and south sides. The retaining wall oundation is at

5 0 below existing ground level. The ground slopes in a North to South direction towards the searont.

Perimeter clearance is to be provided to the north and west sides o the proposed building as shown in Fig. Q6.

A contractors compound is available to the east o the side road.

3. Cladding to the roo and elevations is to be selected to minimise energy consumption and maintenance costs.

A 1-hour minimum re protection is required or all structural members.

4. Windows 6 6 high by 13 0 wide (double) or 9 9 high by 3 3 wide (single) and doors 9 9 high by 6 6

wide (double) or 9 9 high by 6 6 wide (single), are shown diagrammatically.

Imposed Loading

5. Pitched roo, Services 12ps

All foors 100ps Crane capacity required: 2 tons

Site Conditions

6. The site is 66 rom the searont slipway to the South.

Basic wind speed is 102mph based on a 3 second gust; the equivalent mean hourly wind speed is 51mph.

7. Ground conditions below ground level which ollows the sloping ground:

Ground level to 1 6 Loose Clayey Sand. N = 4

1 6 to 16 6 Granular material N= 10 to 40 increasing with depth

Below 16 6 Very Sti Clay C = 3600ps

Ground water was noted at 130

below ground level.


8. Staircase design and the assessment o existing retaining walls but any precautions taken to saeguard their

stability should be stated.



proposed structure including oundations. Indicate clearly the unctional raming, load transer and stability

aspects o each scheme. Identiy the solution you recommend, giving reasons or your choice. (40 marks)

b. Ater completion o your design, the client asks or an extra 540 square eet o oce space within the

existing plan area o the building while keeping the balcony. Write a letter to your client explaining how

this might be achieved advising the structural implications. (10 marks)






e. Prepare a detailed method statement or the sae construction o the building and an outline programme. (10 marks)

7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

18/24


7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

19/24


Question 7. New link bridge between two oshore platorms


1. A new bridge is to be installed oshore, linking an existing utilities platorm with a new living quarters

platorm. The bridge is to be 2133

long, and supported on the two platorms as shown in Figure Q7.2. Bridge clearances at the existing platorm are limited, so the new platorm has been arranged to have

adequate bridge clearance to accommodate the in-line relative movements o the platorms o +/- 1 9,

caused by environmental loadings. Relative lateral displacement o the platorms is also +/- 1 9.

Due to the platorm congurations, the supports at the north end o the bridge are at a dierent elevation to

the south.

3. The bridge is to be ully enclosed, providing weather protection or a personnel access way and piping

and electrical services. The access way is to be 40 wide by 8 3 high.

4. The bridge is to be transported to the oshore site by barge and lited into place by a single crane lit vessel.

Imposed Loading

5. Access way live load 100ps (or personnel access only).

6. Pipes 10 No. 13 OD pipes at 70 lb/t length/each

7. Cable Racks 5No. 1 9 wide x 6 high racks at 35 lb/t length/each

Site Conditions

8. The basic wind speed is 134mph, based on a 3 second gust; the equivalent mean hourly windspeed is 67mph.


9. Fatigue calculations (but not the infuence o atigue on the bridge structure details).



proposed bridge. Indicate clearly the unctional raming, the support constraints, load transer and

stability aspects o each scheme or the relevant temporary and permanent design phases. Identiy the

solution you recommend, giving reasons or your choice. (40 marks)

b. Ater completion o your design, the client inorms you that he wishes to incorporate a large laydown area,

33 0 x 33 0, located on top o the bridge at the South end. The laydown area is to be used during

platorm operations and is to be designed or packages up to 13 0 high, and have a global uniormly

distributed load o 100ps. Write a letter to the client explaining how this might be accomplished and the

eects this would have on your chosen solution. (10 marks)


c. Prepare sucient design calculations, or both the temporary and permanent conditions, to establish the

orm and size o all the principal structural elements and connections, including the support and lit points. (20 marks)


disposition o the structural elements and critical details or estimating purposes. (20 marks)e. Prepare a detailed method statement, including sketches, or the sae transport and installation o the

bridge onto the existing platorms at the eld location. (10 marks)

7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

20/24


7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

21/24


7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

22/24


Question 8. Ofce Retroft


1. An existing oce has been assessed and ound to be substantially decient and requires upgrading to meet

new seismic provisions. The existing structure is an ordinary moment resisting rame (OMRF) structure.

2. The assessment has shown that the oundations are sucient to resist the new seismic provisions and may

be omitted rom urther consideration.

3. The building tenant requires unobstructed open spaces between the internal columns and a glazed elevation

on the perimeter o the building.

4. The seismic upgrade is to be perormed while the building is empty. Internal partitions and nishes have been

removed to allow access to all structural members.

5. The plan o the building with existing moment rames is shown in Figure Q8-1. Figure Q8-2 gives the elevation

o the structure and Figure Q8-3 provides the detail o the existing moment connection. The detail has

been used throughout the building or all OMRF connections with simple shear tabs used elsewhere. All foor

and roo slabs are 10 thick fat slabs with 5 8 diameter bars at 6 centres (characteristic yield

strength o 58,000 lb/square inch each way each direction and are ully composite with the existing steel beams.

The assessment o the slabs ound that they were adequate to carry the existing vertical loads within the structure.

6. All beams are abricated sections made rom 8 x 5 8mm fanges ull strength welded to a

19 9 x 3 8 web. Columns are abricated steel sections made rom 12 x 3/4 fanges ull strength

welded to a 10 x 5 8 web. All abricated steel has a characteristic yield strength o 40,000 lb/square inch.

Imposed Loading

7. Roo 40ps

Floor loading All foors 60ps

30ps allowance or partitions, nishes, service and ceilings load.

8. Figure Q8-4 shows the design 5% damped seismic response spectrum or the region. It applies to level

ground or a 475 year return period, assuming the ground surace is rock with a shear wave velocity o not

less than 2625t/s.

Site Conditions

9. The site is level and located in the centre o a town.

Basic wind speed is 90mph based on a 3 second gust; the equivalent mean hourly wind speed is 45mph.Omit rom consideration

10. Detailed design o stairs. Foundations and ground conditions.


a. Prepare a design appraisal with appropriate sketches indicating two distinct and viable retrot solutions or

the proposed structure. Indicate clearly the unctional raming, load transer and stability aspects o each


b. Ater the design has been completed, the client advises that the building is to be cut back or the top two

foors along the cut out line shown in Figure Q8-1. Write a letter to the client explaining how this might be

achieved and what impact there will be on the design. (10 marks)


c. Prepare sucient design calculations to establish the orm and size o all the principal structural elements. (20 marks)



e. Prepare a detailed method statement or the sae construction o the retrot and an outline construction

programme, including details o any temporary propping required. (10 marks)

7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

23/24


7/29/2019 92b5352f-6b74-4e84-a953-ef93eb08786a

24/24

The Institution o Structural Engineers

International HQ

11 Upper Belgrave Street

London SW1X 8BH

United Kingdom

tel: +44 (0)20 7235 4535

ax: +44 (0)20 7235 4294

[email protected]

www.istructe.org

Registered Charity

Documents

92b5352f-6b74-4e84-a953-ef93eb08786a