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Survey Report
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Structural Survey of the
Newcastle Bangladesh
Association building
March 2011
successful people, projects and
performance
Quality Management
Job No CS/049325-03 Doc No. structuralsurvey/002
Title Structural survey
Location Newcastle Bangladesh Association building(s)
Document
Ref CS049325/structuralsurvey/001
File reference G:\York Work\Jobs\CS-049325-03 Structural Survey - Workshare
Agreement\Reports\structural survey\Structural Survey Report.docx
Date 17 March 2011
Prepared by Sam Parker Signature
Checked by Gary Robson Signature
Authorised
by Gary Robson Signature
Issue No Reason for change Author Date Issued Status
01 First Issue to Durham Office Sam
Parker 17/03/11
Draft
02 Insertion of budget costs to section 4
& 5 J Mason 21/03/11
Final
Name Role
Glen Pendleton Community Assets Co-ordinator
DOCUMENT HISTORY
DISTRIBUTION
Contents
CS-049325-03/structuralsurvey/001
17th
March 2011
Page i
Contents
1. Executive Summary 1
2. Existing Conditions 2
2.1 Site Location 2
2.2 General description 2
2.3 Details of design criteria for existing structure 2
2.4 Site Survey 2
3. Observed Defects 3
3.1 General 3
3.2 Causes of structural defects associated with the ground 3
3.3 Causes of structural defects associated with the structure 3
3.4 Plan of Buildings 4
3.5 Elevation 1 5
3.6 Elevation 2 6
3.7 Elevation 3 7
3.8 Elevation 4 8
3.9 Elevation 5 9
3.10 Elevation 6 10
3.11 Elevation 7 11
3.12 Elevation 8 12
3.13 newer additions to original buildings 13
3.14 Internal Defects 14
3.15 Boundary Walls 15
4. Further investigations required 16
5. Recommendations 17
Executive Summary
CS-049325-03/structuralsurvey/001
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March 2011
Page 1
1. Executive Summary
A visual structural survey was carried out by Sam Parker and Richard Fothergill on
Thursday 3rd March 2011. Access was granted to the property by Mr. Foysel Ahmed.
There were no intrusive survey works carried out i.e. trial pits and drainage surveys.
There was no access to the roof.
In general the buildings on site are in a very poor state of repair. There is evidence
throughout the structures that foundation movement has occurred / still is occurring
causing major structural damage.
Temporary measures could be put in place to halt the progression of some of the
more serious defects but to have a full understanding of the causes of the movement
to determine the best course of final remedial action to take, further investigations are
required.
Temporary measures could include the ‘stitching’ of the large cracks with stainless
steel helical bars grouted in the mortar joints.
Localised underpinning of the worst affected walls could be carried out although this
is an expensive option. This option could also create localised ‘hard spots’ which
could cause further differential settlement.
Further investigations that should be considered are as follows:
• Trial holes to determine size and depth of foundations and nature of
underlying soils
• Drainage survey (condition and pressure testing) to confirm no major defects
• Roof survey (requiring access) and exposing of roof bearings from within the
buildings
Existing Conditions
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March 2011
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2. Existing Conditions 2.1 SITE LOCATION
The buildings included in this report are all those sited at the Newcastle Bangladesh
Association off Elswick Road.
2.2 GENERAL DESCRIPTION
The older established buildings are two storey and are of brick construction with a
composite steel beam and concrete roof. The majority of the later additions appear to
be of concrete block construction with concrete render.
2.3 DETAILS OF DESIGN CRITERIA FOR EXISTING STRUCTURE
There have been no archive or historic drawings or reports issued and no intrusive
investigations were carried out so the foundation types are unknown. The age of the
building implies that the foundation type may be brick corbelled footings which were
generally constructed at a relatively shallow level.
2.4 SITE SURVEY
A visual structural survey was carried out by Sam Parker and Richard Fothergill on
Thursday 3rd March. Access was granted to the property by Mr. Foysel Ahmed.
There were no intrusive survey works carried out i.e. trial pits and drainage surveys
etc.
There was no access to the roof.
Observed Defects
CS-049325-03/structuralsurvey/001
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March 2011
Page 3
3. Observed Defects
3.1 GENERAL
The following pages show elevation photographs of the various walls of the buildings
and highlight any significant structural defects visible from ground level.
Possible causes of the defects are shown below.
3.2 CAUSES OF STRUCTURAL DEFECTS ASSOCIATED WITH THE GROUND
• Differential Settlement induced by unequal foundation pressures arising from
such factors as extensions added to existing buildings or concentrated loads,
for example under chimneys
• Ground subsidence and heave due to volume changes in clay soils
• Movement due to consolidation of poor ground or made ground (this usually
manifests itself within the first 10 years of the life of the building, in the form of
progressive damage)
• Movement caused by nearby excavations
• Erosion of fine soil particles due to the passage of water, for example a
leaking drain. This can, over many years, bring about localised subsidence
damage by slowly washing away the fines in the soil, or softening of the
ground
3.3 CAUSES OF STRUCTURAL DEFECTS ASSOCIATED WITH THE STRUCTURE
• Material shrinkage and creep
• Corrosion or decay caused by water ingress / lack of maintenance
• Differential thermal movements in dissimilar materials
• Poor detail design or workmanship
Observed Defects
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3.4 PLAN OF BUILDINGS
ELEVATION 1 ELEVATION 2
ELEVATION 3
ELEVATION 4
ELEVATION 5
ELEVATION 6
ELEVATION 7 Newer additions to
original building
ELEVATION 8
Observed Defects
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Page 5
3.5 ELEVATION 1
Elevation 1 (Old electrical sub-station)
Diagonal crack following mortar line from bottom left to top right of the elevation. Crack
size increasing towards top right suggests differential settlement of building foundations
(crack width reaches a maximum of approx 40-50mm).
The upper side of the crack steps in an outwards direction from the lower wall by up to
15mm in places.
The crack has been re-pointed in the relatively recent past.
The concrete roof ‘overhang’ is in very poor condition – signs of spalling and cracking.
No expansion joints observed.
The green line represents a 10mm step out of the wall. This is the approximate position
of the internal ground floor level.
There are areas of minor cracking and mortar loss over the entire elevation.
Shows a lintel with a ‘blown’ face – loose material to be broken out and
rendered to prevent falling debris.
Observed Defects
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3.6 ELEVATION 2
Elevation 2
Major vertical cracking and bulging at the top left hand corner of the elevation – this requires immediate attention.
The green line represents a 10mm step out of the wall. This is the approximate position of the internal ground floor
level.
No expansion joints observed.
Observed Defects
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3.7 ELEVATION 3
Elevation 3
There are many minor diagonal cracks throughout the
elevation.
The above photograph shows a vertical crack propagating
up the upper section of the wall and between the concrete
roof panels. This shows the scale of lateral movement that
has taken place. The separation of the roof structure has
inevitably resulted in the ingress of water (which in time will
result in more damage) – this is believed to be true
throughout the main building.
No expansion joints observed.
The green line represents a 10mm step out of the wall.
This is the approximate position of the internal ground floor
level.
Observed Defects
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3.8 ELEVATION 4
Elevation 4
There are minor diagonal cracks throughout the elevation (up to 5mm).
There is an obvious diagonal crack extending from the bottom right of the wall. The crack is relatively consistent along
its length at approx 10mm in thickness. This suggests a lateral ‘shift’ caused by tension in the brickwork. Again,
Inadequate foundations or differential settlement of the foundations are the likely cause.
Observed Defects
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3.9 ELEVATION 5
Elevation 5
The area of most concern is the lower right hand corner of the elevation between ground level and the door lintel. The
photograph to the right shows how the wall has shifted and rotated. This movement has caused the diagonal crack from the
door lintel.
No expansion joints observed.
There is minor cracking throughout the elevation.
25 mm
Observed Defects
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3.10 ELEVATION 6
Elevation 6
There are several diagonal cracks through the chimney breast and to the left of the
elevation resulting in openings up to approx 10mm.
There are minor diagonal cracks around the window openings which could be due
to inadequate lintels or as a result of general movement/settlement linked to the
foundations.
Mortar loss is present throughout the wall which will lead to further damage in
freeze/thaw conditions etc.
There is minor cracking throughout the elevation.
Observed Defects
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3.11 ELEVATION 7
Diagonal cracking through infill
panel propagating from
protruding pipe
Diagonal and vertical cracking
from window openings
Diagonal cracking from window
out to corner of building.
Cracking along the top of the
bottom course of brick to
underside of old window cill.
Elevation 7
No major problem was identified on this elevation, only minor to moderate cracking which implies
foundation movement.
No expansion joints observed.
Observed Defects
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3.12 ELEVATION 8
Elevation 8
Large cracks exist above the fire exit doorway (left photograph), above the window to the right of the
doorway (top right photograph) and above the embedded steel beam (above photograph). These are
all signs of foundation movement / rotation.
Minor cracks and mortar loss are present throughout the elevation.
Observed Defects
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3.13 NEWER ADDITIONS TO ORIGINAL BUILDINGS
Boundary wall forms integral part of
structure. No Damp Proof Course
observed. Damp issues within the
building.
Flat roof appears in poor condition. Felt
seams have de-bonded in areas
resulting in water ingress.
Concrete footings appear to be shallow
leaving them susceptible to settlement
and lateral movement.
Newer additions
Generally the single storey additions have been built
to a very poor standard and/or design.
The brick faced entrance, shown in the photograph to
the right is built into the boundary wall. This boundary
wall is in very poor condition, looks to have little to no
foundations and has no damp proof membrane.
Damp, and problems associated with damp, within the
building is inevitable.
Definite foundation sizes and depths are not known
but assumed to be shallow
Observed Defects
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3.14 INTERNAL DEFECTS
First floor toilet block, main building
Loose wall tiles throughout and gaps between wall and
false ceiling. Mr. Ahmed informed us that during recent
high winds all ceiling tiles fell down. This indicates high
levels of movement within the roof structure.
Movement of the foundations and dropping of the walls
could have resulted in the roof steels losing
ties/bearing to the walls thus swaying/uplifting under
high wind loading.
Peeling paintwork suggests water ingress.
First floor room, sub-station building
Large cracks between windows in newly plastered
room. These are signs that the differential
settlement/movement of the foundations is
PROGRESSIVE and therefore of great concern.
Single storey addition
Large cracks are present throughout of the internal
walls of the single storey additions. They exist
between adjoining walls and between walls and
ceilings.
First floor, Main building
Evidence of water ingress in the form of water stains
on ceiling tiles.
Internal Defects
Major cracks and evidence of wall movement are present throughout the single storey additions. This supports the
assumption that poor quality shallow foundation are present, and that the additions are tied to the unstable boundary
wall.
In the main building minor cracks and bulges exist throughout. The more major issues are at first floor and ceiling
levels where movement of the roof structure is evident.
Observed Defects
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3.15 BOUNDARY WALLS
Boundary walls
There are major cracks located around the entire boundary
wall, a selection of them have been shown in the
photographs to the left. All these cracks show sign of
differential settlement i.e. the crack widens/narrows up the
wall as the adjacent wall rotates with the foundation.
There are also areas of ‘blown’ brick faces caused by freeze
thaw action.
Mortar loss is prevalent throughout.
Running repairs have been carried out over a period of time
including re-pointing and the infilling of various doorways
and window openings.
Infill panels have not been tied into the surrounding
brickwork resulting in them falling away.
Further investigations required
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4. Further investigations required
It is recommended that the following investigations are undertaken to determine
uncertainties identified in this report.
Item Description Budget Cost
1.0 Drainage Survey- to assess the condition of drainage
pipes with a view to identify potential fractures
600.00
2.0 Desktop Study- to determine whether there is potential for
unacceptable ground risk within the site
1,500.00
3.0 Ground Investigation- Hand dug pits to determine the
nature of the foundations and sample boreholes to identify
the soil characteristics.
7,500.00
4.0 Crack Monitoring- Installation of glass tell tails to monitor
the activity of cracks over a 12 months period. It is
suggested the tell tails are installed after a firm diagnosis
has been made.
2,500.00
5.0 Full roof survey – this will include inspection from above
(requiring access), and also an inspection from below by
removing sections of the false ceilings (especially in steel
beam bearing locations and areas where major cracking is
visible from outside i.e. Elevation 2)
1,200.00
Recommendations
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March 2011
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5. Recommendations
Subject to the findings from further investigations listed in section 4, it is considered
the following remedial works will be necessary to strengthen the structural stability of
the building.
Item Description Cost (£)
1.0 ‘Stitching’ - Use helical bars for crack stitching masonry
repairs and brickwork reinforcement of cracked walls. By
stitching wall cracks and lintels, masonry walls are stabilised
and structural integrity is restored. This would be
recommended in all areas with major cracks.
8,000.00
2.0 Breaking out and replacing sections of walls – this is for
areas of extensive damage, including leaning or bulging
walls, or where there’s loss of bearing below beams
10,000.00
3.0 It is recommended that the boundary wall is reduced in
height to limit the progression of settlement/rotation. In the
long term it is advisable that the wall is taken down and
rebuilt on adequate foundations
8,000.00
4.0 Underpinning – this could be carried out using mass
concrete or mini piles. This is an expensive option and risks
further damage during installation
100,000.00
5.0 Roof repairs / rebuild – the extent of the work needed to the
roof will become clear after further investigations
5,000.00
6.0 Some areas of brick may need breaking out and replacing
(areas where major cracking is occurring such as those
identified on Elevation 2)
3,000.00
Budget Cost £134,000.00
Recommended