keltbray piling capability document (circa 2013)
TRANSCRIPT
London Underground
Capability Document
Keltbray Piling comprises a team of experienced and dedicated personnel able to
identify, eliminate and manage ground risk from initial enquiry stage through to
successful completion on site.
Keltbray Piling possess modern CFA and traditional Rotary Bored piling rigs and
equipment, capable of installing piles of up to 2.4m in diameter to depths in excess
of 50m. We have a growing track record in piling related activities such as pile
removal, plunge column installation and the harnessing of geothermal energy
through piling.
One of the significant advantages of Keltbray Piling is that we are able to work
integrally with our sister companies, reducing interfaces on site to the benefit of the
project as a whole. In order to bridge these interfaces we are able to work either as
principle contractor or as traditional sub-contractors, managing all issues
associated with our works.
We pride ourselves in offering solutions that best fit the problems presented rather
than simple product selling. To support this philosophy our experienced staff are
able to specify, design, manage and install a broad range of piling and
geotechnical solutions including Rotary & CFA piles and retaining walls, sheet piles
and ground anchors.
Through our close relationship with our in-house Geotechnical and Structural
Engineers, Wentworth House Partnership, we are able to offer a full design and
construction service package. Our design team consistently develop sustainable
and innovative solutions, working in accordance with the latest codes and
standards.
We are proud to be active members of the Federation of Piling Specialists.
As befits the philosophy of the Keltbray group, Keltbray piling welcome the
opportunity for early contractor involvement in order to develop the right solution
for your project.
We look forward to working with you.
Stuart Norman
Managing Director, Keltbray Piling
Our Capability
Lancaster Gate
“To provide our clients with a
quality foundation design and
construction service. Where
possible we will draw on our
broad range of skills and
services as Keltbray Group to
deliver a shorter construction
programme, safely and
economically”
Our Mission
Sample of Keltbray Group Projects within Central London
R-622 CFA mode at Project Aurora, Gatwick
R-622 CFA mode at 375 High Street Kensington
How Piling fits in with the Keltbray Group
Sample of Keltbray Group Projects within Central London
Piling
Wentworth House
Partnership
Rail
Environmental
Demolition
Reasons to choose Keltbray Piling – Our Key Strengths
1. Being part of the Keltbray Group
enables Keltbray Piling to overlap with
the demolition phase and the following
ground works packages offering a
shorter programme and reduced
interfaces on site.
2. Our technical expertise through support
of in-house Structural & Geotechnical
Engineering consultants WHP.
3. Engineering, co-ordination and
integration of temporary works with the
permanent works piling solution
4. Flexibility and commitment to our
customers - A quality product delivered
safely, on time and to budget.
5. Strong service offering to include: CFA,
Rotary Bored, Mini and Rail Piling,
Deep Basement Construction, Rotary
Coring and Plunge Column Installation.
St. James Square
David Roy
Estimating & Proposals
Manager
Team Structure
John Price
Keltbray Group
Managing Director
Stuart Norman
Managing Director
(Piling)
Lee Cain
Senior Contracts
Manager
Stuart Marchand
Wentworth House
Director
Jan Jones
Business Development
Leader
Wentworth House
Structural &
Geotechnical Design
Engineers
John Sykes
HSEQ
Keltbray Group
Greg Haynes
Commercial Manager
Team Structure
Keltbray Piling
Keltbray Group
Wentworth House
Technical Excellence
We work closely with our in-house Geotechnical and Structural Engineers.
Wentworth House Partnership (WHP). We therefore are able to offer a full
design and construction service package. Our design team are driven to
develop sustainable and innovative solutions, working in accordance with the
latest Eurocodes and design standards.
WHP have a dedicated Geotechnical Engineering team offering all aspects of
support from practical advice through to complete finite element based
design. We currently comprise of a team of 4 Geotechnical Engineers from
Director to Graduate level.
We pride ourselves in designing value Engineered, alternative solutions for
our clients and our current Geotechnical services include:
• Piling, temporary works and basement construction advice
• Specification , supervision and management of site investigation works
• Detailed Retaining Wall and Bearing Pile Design across a multitude of
techniques and disciplines
• Mini & Micro Pile Design
Our design capability is enhanced through the use of the latest software
packages including PLAXIS, Adsec, WALLAP, PIGLET, Geoslope & CADS
and is further supplemented through extensive experience and use of in-
house design programs.
Piling Solutions Offered
We offer a range of techniques to support the solutions
we offer outlined as follows:
Small and Large Diameter Piling
• Continuous Flight Auger Piling (CFA)
• Traditional Large Diameter Piling (LDP)
• Plunge Column Piles
• Large diameter coring works
Retaining Wall & Deep Basement Construction
• Secant Piled Walls
• Contiguous Piled Walls
• King Post Walls
Mini & Micro Piles
• Sectional Flight Auger (SFA)
• Mini Case & Auger
• Self Drilled Micro Piles
Rail Piling (off RRV’s)
• Driven Steel tubular piling
• Case & Auger piling
CFA Augers on CM50
Continuous Flight Auger (CFA) Piling
Advantages of CFA Piling:
• Speed – This system is typically quicker to install than traditional
rotary bored piles
• Cost – Owing to it’s speed, costs are also lower than traditional
rotary bored piles
• Low noise & vibration – The system is vibrationless, without large
peaks and troughs in noise emissions
Our CFA Fleet Capability
• We possess a modern fleet of CFA rigs comprising Soilmec R625,
R622, CM50 & R312
• Our rigs are fitted with the Lutz instrumentation system whereby
installation parameters are monitored and recorded for every pile
• 350mm to 1200mm diameter
• Depths of up to 28m
• We carry a range of equipment , including extra heavy duty augers
for deep basement construction
CFA Augers on CM50
Large Diameter Piling (LDP)
Advantages of LDP Piling:
• Ability to core through obstructions – Various tools are available
to ensure coring through a range of obstructions
• Depth capability – With the right kelly bar extension, this system is
capable of installing up to 80m deep piles
• Visual inspection of the piling bore and ground conditions – As
the ground is excavated in short “bites” each layer and the base of the
piles are easily inspected
• Increased load bearing capacity and verticality over CFA
Our LDP Fleet Capability
• Our Fleet is dual capability and the R625, R622 & R312 are all
capable of installing traditional rotary bored, large diameter piles (LDP)
• Diameters of 450mm to 2400mm are available
• Depths of up to 50m are achievable
• We carry a range of equipment , including rock augers, casings and
cleaning buckets to allow deep pile construction within a range of
ground conditions
• We have a growing track record in piling related activities such as pile
removal, plunge column installation and the harnessing of geothermal
energy through piling.
R622 at City Road
Deep Basement Construction
Our specialism as a Piling company and as a group lies within deep basement construction in confined inner city centres.
Below is a project list of our most recent achievements:
Project Scope Max Retained Height
Technique Value
Parabola (Holland Green)
650No 900mm diameter 10m Rotary Bored (Hard/Firm Secant)
£2.3M
259 City Road 173No 900mm dia 10m CFA (Hard/Firm Secant) £0.85M
151 City Road, London
150No 900mm dia 12m Rotary Bored (Hard/Firm Secant)
£1.1M
W4 – Regent Street, London
200No 600mm dia 6m CFA (Hard/Firm Secant) £1.1M
7-8 St James Square, London
100No Secant wall & 30No Contiguous wall piles, 900mm dia
12m Rotary Bored £1.25M
Deep Basement Construction
151 City Road 151 City Road
259 City Road, CFA Secant
Mini, Micro and Restricted Access Piling
We have the capability to design and install the following mini and
micro pile techniques in restricted access conditions:
Sectional Flight Auger (SFA) 350mm to 600mm diameter
Mini Case & Auger – 350mm to 600mm in diameter
Self Drilled Micro Piles – Various diameters up to 250mm
Through our network of contacts either by cross hire or sub-contract
we have the flexibility to design, manage and install an extensive
range of mini and micro piling techniques.
Our labour force is multiskilled across a range of disciplines and
through our network of contacts we have the flexibility to design,
manage and install an extensive range of mini and micro piling
techniques.
Casagrande C6 in Micro Piling mode at Three Quays
Trackside/Rail Piling
Having recently completed the first phase of the Liverpool to
Manchester piling works for overhead line electrification, our Rail piling
division has growing expertise and experience.
Keltbray Piling in conjunction with our Keltbray Rail division can work
via our own Principal Contractors licence and fleet of 228 Road Rail
Vehicles (RRVs).
We have a growing fleet of Movax vibratory and Fambo hydraulic
hammers capable of installing 610mm diameter steel piles to depths
in excess of 15m.
We have also developed a range of solutions to overcome pile
installation issues in difficult ground conditions in association with our
clients.
Liverpool to Manchester, Fambo Driving Hammer
Proven Ability to Deliver: Our Recent Project History (2011-2013)
Most Recent Projects
Bearing Piles Retaining Walls Coring &/or Plunge Cols
Value
Mini Piling or restricted access
CFA 350-1200 Mm
LDP 750 mm or less
LDP >750 mm
Contiguous - CFA 600mm dia or less
Contiguous -CFA >600mm
Secant CFA
Secant Rotary Bored
Holland Green (formerly The Parabola)
£2.3M
259 City Road, London
£0.85M
151 City Road, London £1.10M
W4 – Regent Street, London
£1.10M
7-8 St James Square, London
£1.25M
261 City Road, London £0.78M
2-14 Baker Street
£0.60M
Proven Ability to Deliver: Our Recent Project History (2011-2013)
Most Recent Projects
Bearing Piles Retaining Walls Coring &/or Plunge Cols
Value
Mini Piling or restricted access
CFA 350-1200 Mm
LDP 750 mm or less
LDP>750 mm
Contiguous - CFA 600mm dia or less
Contiguous -CFA >600mm
Secant CFA
Secant Rotary Bored
3 Quays, London £1.1M
Fulham Reach £630K
Tesco, Woolwich £500K
Caius House, Battersea £500K
Pembury Circus, Hackney
£500K
Witanhurst House, London
£1.2M
Wapping Lane Phases 1 & 2
£420K
Bolsover Street £155K
Sea Containers House £600K
Aurora, Gatwick £350K
Contract Profile
Holland Green (formerly The Parabola)
Challenging Projects Require Innovative Solutions
Keltbray Group were appointed by Chelsfield Developments for
the demolition, enabling works, piling and bulk excavation for a
new extensive basement on the site of the former
Commonwealth Institute in Kensington.
A 465lm hard/firm secant piled wall, designed by the Clients
Engineer, Arup was required to be installed for a new double
storey basement. The project has been made all the more
complex owing to the existing grade 1 listed structure of the
commonwealth institute and it’s requirement to be retained and
incorporated into the new structure.
Utilising low headroom piling techniques in pre-defined locations
around the existing structure, the secant wall was installed under
the extended canopy of the existing signature Parabolic roof. The
remaining locations of the wall were installed with large 90Ton
piling rigs with the tight programme calling for a peak of 5 piling
rigs working on site at any one time.
The Clients specification called for pile verticality tolerances
of 1:200 determining the need for traditional, rotary bored
techniques
Pile installation took place in a defined sequence, adjacent to
controlled demolition activities with the Keltbray Group works
package offering the Client significant programme saving as
opposed to more traditional procurement methods.
Keltbray delivered a high quality product under the
supervision of the Arup resident Engineer with the works also
completed on programme.
Keltbray Piling were also responsible for the installation of the
small diameter mini piles in order to support the Parabolic
roof in the temporary condition. These piles were designed in
accordance with Euro codes and installed in restricted
headroom conditions to stringent settlement criteria.
Location: High Street Kensington, London
Client: Chelsfield Developments
Main Contractor: MACE
Quantity Surveyor: Davis Langdon
Structural Engineer: Arup
Value: £2.3M
Programme: 13 Weeks
Scope: 653No, 900mm dia Rotary Bored hard/firm
secant piled wall with pile lengths up to 24m.
Contract Profile
257-259 City Road, London
The original scope of works comprised a cantilever contiguous
pile wall and 900mm diameter bearing piles for the construction
of a new 25 storey tower with double basement.
As a direct result of the Keltbray works at 151 City Road and after
close inspection of the ground investigation report, we
recommended the use of a partially propped secant piled wall to
limit the horizontal deflection along the sensitive boundary with
the deep lying LUL Northern Line. Also, to speed the basement
excavation process and keep the internal space as free from
temporary works as possible, Keltbray designed and installed a
connecting contiguous piled buttress wall behind and
perpendicular to the secant wall.
The 900mm diameter Continuous Flight Auger (CFA) secant piled
wall was installed to a verticality of 1:75 with hard/firm piles spaced
typically at 0.7m c/c.
Piles were designed in accordance with Euro code 7 and
during the installation of the secant wall a rotary bored rig
was mobilised to site to install a 780mm diameter preliminary
test pile. The test pile was instrumented with Brillouin Optical
Time-Domain Reflectometry with support from Cambridge
University as well as traditional strain gauges.
Unusually for the laminated bed lithogy of the Lambeth
Group, the rotary bearing piles were bored dry and concreted
within 30 minutes of exposing the base. This methodology
was adopted for the test pile, which performed extremely well
allowing all subsequent contract bearing piles to be installed
at the reduced diameter of 780mm.
This reduction in diameter ensured increased bearing pile
production rates allowing the overall piling programme to be
completed on time and to budget.
Location: 257-259 City Road, London
Client: Ardmore
Main Contractor: Ardmore Construction
Quantity Surveyor: Ardmore
Structural Engineer: URS
Value: £830,000
Programme: 10 weeks
Scope: 173No 900mm CFA Secant Piles 18m
deep for a retained height of up to 9.3m.
88No 880/780mm dia, 12No 600mm dia
Rotary Bored bearing piles to depths of
31m below ground level.
Challenging Projects Require Innovative Solutions
Challenging Projects Require Innovative Solutions
Contract Profile
W4, Regent Street
Keltbray Group were appointed by the Client Crown Estates for the
demolition, facade retention and piling works at the W4 site
immediately behind Regents Street in London.
Keltbray Piling were employed to design and construct rotary bored
bearing and Continuous Flight Auger (CFA) hard/firm retaining wall
piles. The original scheme showed 1800mm diameter piles around
the perimeter which Keltbray value engineered to be pairs of 600mm,
750mm & 900mm diameter.
Piles were designed in accordance with Eurocode 7
Bearing Piling works commenced with the use of an R312 rig in June
2012 with all works undertaken from existing basement level. The site
was typical of inner city London being logistically challenging with all
deliveries and spoil removal taking place via an access ramp.
Pile installation took place in a defined sequence, adjacent to
controlled demolition activities allowing Keltbray to offer the Client
significant programme saving as opposed to more traditional
procurement methods.
A CM50 piling rig was mobilised to install the 600mm diameter
CFA secant box, with piles supporting vertical and additional
horizontal loads from the adjacent grade 1 listed vaults. The
secant piles were installed to a verticality tolerance of 1:75 with
the wall alignment adjusted to suit the boundary conditions
around the site.
Within the area of the listed vaults, 450mm diameter mini piling
works were completed based on the use of a Klemm 709 piling
rig. Concrete for these piles was lifted across site by the Tower
Crane involving detailed, daily co-ordination between ourselves
and all parties on site.
The successful piling works were completed on programme.
Location: Regents Street, London
Client: Mace
Main Contractor: Mace
Quantity Surveyor: TBC
Structural Engineer: Waterman
Value: £1.1M
Programme: 19 Week Piling Programme
Scope: Design and installation of 113No 900mm,
750mm & 600mm diameter traditional rotary
bored bearing piles to depths of 35m. Installation
of guide walls and 115lm of 12m deep 600mm
diameter CFA piles for the additional storey
basement comprising a hard/firm secant wall
box.
Design and installation of 40No, 450mm
diameter case & auger mini piles, 24m deep.
Contract Profile
151 City Road
Located on City Road just off Old Street roundabout in
London is the site of the new Montbatton Hotel. The
proposed hotel is a 22 storey structure with a 3 level
basement.
Directly opposite the site is Moorfields eye hospital. During
the construction phase Keltbray Piling had to ensure that the
induced vibrations were at an absolute minimum.
Wentworth House Partnership were responsible for the
geotechnical design on behalf of Keltbray Piling. The scheme
was designed in accordance with Eurocode 7 and group
analysis was carried out on the bearing piles to reduce the
overall number of piles. Engineering advice was also
provided in order to transfer structural load to the perimeter
retaining wall.
Keltbray Pilings scope was to install guide walls, secant piled
wall, construct load bearing piles and remove pile arisings
from site.
The 880mm diameter secant piled wall was installed using
the traditional rotary bored method to achieve verticality
tolerances of 1 in 150. The wall comprised of 92no male and
female piles with interlock to a level of 12 metres and male
piles extending to 22m.
The 750mm diameter bearing piles were also constructed
using the rotary bored method from the high level and
concrete cut off at formation level some 11 metres below
ground. The piles were up to 30m long and were founded in
the Lambeth formation.
The works were completed on time and to budget, for a very
satisfied client.
Location: 151 – 157 City Road, London
Client: SGP Contracts
Main Contractor: SGP Contracts
Quantity Surveyor: n/a
Structural Engineer: Curtins Consulting
Value: £1,300 000
Programme: 16 weeks
Scope: Installation of guide walls, 880mm secant wall,
750mm diameter bearing piles , Fully
instrumented preliminary test pile and removal of
pile spoil.
Picture size is 5.7
x 8.1 position is
9.68 x 6.62
Picture size is 5.7
x 8.1 position is
1.19 x 6.62
Picture size is 5.7
x 8.1 position is
18.16 x 6.62
Challenging Projects Require Innovative Solutions
Location: 7-8 St James Square, London
Client: Galliford Try
Main Contractor: Galliford Try
Quantity Surveyor: Galliford Try
Structural Engineer: Price & Myers
Value: 1,178,380.02
Programme: 39 weeks
Scope: 39No 900mm Rotary Contiguous Wall Piles
11 no 900mm Temporary Contiguous Wall piles.
95 no 900/750mm Secant Wall piles 37 no
750mm CFA Temporary Secant Wall, 61 no
750mm bearing piles 19 no 750mm Temporary
works piles 8 no 750mm tower crane piles and 22
no 340mm restricted headroom mini piles.
Challenging Projects Require Innovative Solutions
Contract Profile 7-8 St. James Square
Piles were designed in accordance with Eurocode 7 and
Keltbray designed a scheme with all bearing piles being
880/750mm diameter to minimise the amount of plant and
tool on site. A number of the wall piles and bearing piles had
UC installed for either propping the wall or for temporary
works.
Works in the basement of no 7 St James consisted of
340mm restricted headroom mini piles, these where
constructed using bored or SFA techniques depending on
the ground conditions. These piles then had UC or
reinforcement cages installed in 1.5m sections to support the
internal columns or walls and allow the basement to be
deepened.
Keltbray Piling were appointed by Galliford Try Construction for
the piling works at 7-8 St James Square, London. The original
scope of works comprised a propped contiguous pile wall and
600/750/900mm diameter bearing piles for the construction of a
new office development and mini piling for the extension of the
basement to no 7 St James Sq.
The first phase of the works were carried out from street level
from a propped slab to allow demolition work to continue.
During this first phase we had a change in ground conditions as
we discovered and old tributary to the river Tyburn. This
change in ground conditions lead to change from a contiguous
wall design around the parameter to secant wall design and a
change in the temporary pile layout due to increased prop
forces. Due to the river Tyburn clay levels would vary
dramatically over the site with levels changing by a much as 5m
within 3m horizontally.
Contract Profile
Three Quays
Keltbray Piling have completed works on the piling phase of the
Three Quays project. The site is located adjacent to the Tower of
London and has been developed for both retail and residential
purposes. The site is of significant archaeological interest, on the
banks of the Thames and additional geotechnical challenges
have been overcome relating to the tidal influence on the
groundwater and the sub-artesian groundwater pressures within
the Lambeth Group.
Keltbray Piling were employed initially to install 128no bearing
piles with diameters ranging from 600mm to 1500mm and to
depths of 32 metres.
The project was particularly challenging as there were several
existing piles and quay wall that had to be cored out to allow the
installation of the new piles.
The pile design was carried out in accordance with Euro code
7, an early working test pile to a load of 10MN was carried out
to ensure any risk was mitigated with results being better than
predicted.
Keltbray Piling had a 10 week programme and completed
works two weeks ahead of contract completion date.
Keltbray Piling were responsible for providing all attendances
required and removing the pile arisings from site which was all
carried out by in house divisions allowing the Main Contractor
to liaise with one single management interface.
On the strength of the relationship that was formed during the
piling phase Keltbray have now secured the substructure and
temporary works package for the project.
Challenging Projects Require Innovative Solutions
Location: Lower Thames Street, London
Client: Cheval Group
Main Contractor: Mace
Quantity Surveyor: Gardiner & Theobald
Structural Engineer: Ramboll
Value: £1.6M
Programme: 10 weeks
Scope: Installation of 128no LDA piles from 600mm-
1500mm diameter, 10MN load test, Provide on
site welfare, provide piling and attendance and
muck away and associated attendances.
Challenging Projects Require Innovative Solutions
Contract Profile
2-14 Baker Street
Challenges – Site is a small site bounded on 4 sides by public
highways including Baker Street to the west. During the
demolition and enabling works, prior to our involvement, there
was a poor relationship with some residents of the adjacent
Bakers Mews properties. This resulted in additional restriction
being placed on deliveries by Westminster Council.
The piling platform was provided at 2 levels, further restricting the
available working space on site.
Bearing piles and 600mm secant piled wall were completed on
programme without significant difficulties, despite the mobilisation
to site of additional contractors to carry out construction of tower
crane base and installation of 160m deep geothermal boreholes.
Construction of 900mm secant wall piles was complicated by the
presence of existing temporary works soldiers and raking props.
It was necessary to construct the secant wall in short sections
including the provision of new temporary works kingposts to
allow removal of the original temporary works before
completing the secant wall. This requirement made
sequencing and construction of the secant wall construction
difficult with the requirement to cut female piles with a large
difference in age, (up to 20 days in some locations).
Location: 2-14 Baker Street
Client: British Land
Main Contractor: Mc Aleer & Rushe
Quantity Surveyor: n/a
Structural Engineer: Ian Black Consulting
Value: £608,871.03
Programme: Original contract period 10 weeks
Scope: Construction of bearing piles and secant wall piles
for construction of nominal 6m deep basement and
structure above. ( to be extended due to additional
works instructed and delays).
Challenging Projects Require Innovative Solutions
Contract Profile
Holiday Inn, Commercial Road
The project location was originally a fuel garage, which was taken
down to commence the works for the proposed Holiday Inn.
Ashridge Construction Limited (ACL) were awarded this major
hotel construction project with Willmott Dixon, where works
comprise of enabling works and piling mat, ring beam and
support system, basement dig, drainage and storage tank
system, 1200m2 basement slab and an all concrete works
package which includes walls, columns, lift shafts, in-situ stairs
and access ramp from basement to 2nd floor. ACL commenced
work on site in December 2010 with a planned completion date of
May 2011. There were under ground large fuel tanks which
were removed so that foundation works could commence.
Keltbray’s scope of works were to install the continguous wall
piles, 254 nr, using CFA technology and the internal bearing
piles using the rotary piling method, 107 nr piles. The challenge
on this job was the restricted site size. Keltbray had 2 rigs, the
CM50 and R312, to do the two different piling techniques. A
Kobelco crane serviced the rotary rig by installing 9m long
casings by vibrating them into the ground. The upper layers of
ground above London clay were unstable that a 9m length liner
had to be used for all bearing piles.
Due to the initial delays owing to “TFL” consents ACL had to
work beside our piling to make sure that the project was well
on its course for completion within time. ACL had their crew
and 3 excavators. All works were planned and executed
carefully and safely to make sure there were no delays.
Location: 261-267, Commercial Road
Client: Holiday Inn
Main Contractor: Willmott Dixon
Quantity Surveyor: n/a
Structural Engineer: One Creative Environment Ltd
Value: £250,000.00
Programme: 7 weeks
Scope: 254 CFA piles and 107 rotary bearing piles
Challenging Projects Require Innovative Solutions
Contract Profile
Selbourne House
Selbourne house included the demolition and redevelopment
of a large commercial building.
Keltbray Ltd were responsible for the demolition of the
existing building and the permanent enabling works on site.
Due to the existing basement, the site surround needed to be
retained to enable the demolition and future redevelopment
works to continue.
A sheet pile wall was used as the retaining wall but the
removal of the redundant foundations was required before its
installation. Keltbray Piling were responsible for removing
such obstructions which included a layer of solid concrete,
sometimes over a meter thick located roughly 6 meters
below GL.
Keltbray Piling identified a Coring method to be suitable to
remove the obstructions. Due to the depth of the concrete in
the ground, a large Rig (SR-60 Piling Rig) was required to
undertake the work.
As the demolition works was incomplete, the basement first
floor needed to be Back Propped to support the Coring
operations which were already restricted to a tight space on
site.
Considering the sizeable ground obstructions and the
limitation to piling operations, the job was very successful as
80 meters of Coring work was completed within a 6 week
period
Location: Victoria, London
Client: Sir Robert McAlpine
Main Contractor: Keltbray LTD
Quantity Surveyor: n/a
Structural Engineer: n/a
Value: £100K
Programme: 6 Weeks
Scope: Coring Works – Removal of redundant
foundations
Challenging Projects Require Innovative Solutions
Contract Profile
Witanhurst House
Located in Highgate in a quiet residential area, the
redevelopment of Witanhurst House will be one of impressive
prestige considering the scale of this privately owned
property. Having demolished the north-eastern wing of the
existing house, the construction of a 10m deep basement
beneath the front courtyard was required in the development.
We were required to design and construct a retaining wall to
facilitate Top Down Construction of the double basement .
The only means of access to the site for all plant and
equipment was through an 2.9m wide by 3.7m high gateway
which required intricate logistics planning.
Ground conditions basically consist of a thin upper layer
(1m) of made ground overlying a sandy silt clay proven up to
25m.
Site restrictions required an initial King Post Retaining Wall to
maximise space and to ensure the protection of the existing
trees which was achieved using a Mini-Piling Rig.
The Basement Enabling Works entailed a Retention Pile
design where both a Secant Pile Wall and a Contiguous Pile
Wall were used. Concerns about ground water required both
methods to be employed.
Bearing Piles were constructed using a Rotary LDA method
where some piles required the installation of Plunge Columns
to facilitate Top Down Construction assisting in decreasing the
projects construction period. A Soilmec R-625 Piling Rig was
used to construct both the retaining wall and the Load Bearing
Piles. Plunge Columns were placed using a Specially
Fabricated Frame to achieve the required precision tolerances.
Location: Highgate
Client: WCML
Main Contractor: WCML
Quantity Surveyor: n/a
Structural Engineer: Michael Barclay Partnership
Value: £1.2m
Programme: 3 months
Scope: Design and Construction of:
•Contiguous Pile Wall
•Secant Pile Wall
•LDA Bearing Piles
•Plunged Columns
Contract Profile
365 High Street Kensington
Located in the heart of the Royal Borough of Kensington and
Chelsea, one of London's most prestigious neighbourhoods,
375 Kensington High Street will offer a selection of luxurious
one, two and three bedroom apartments and penthouses. Each
home will combine the finest quality materials with the highest
levels of design and the latest innovations in technology to
create the very best in modern city living.
St Edward Homes were the client on the project, Keltbray Piling
were employed by PJ Carey who were the substructure
contractor.
Keltbray scope was to install guide walls, install 450 linear
metres of secant piling, pile attendances and clearing of pile
spoil.
The secant wall is to be one of the largest walls constructed
using CFA techniques with a retained height of 8 metres. The
wall was part cantilevered using 750mm and 900mm diameter
piles and part propped using 600mm diameter piles.
Keltbray utilized two high torque Soilmec R625 rigs to execute
the works and completed works in 9 weeks, some 3 weeks
ahead of schedule.
Location: 375 High Street Kensington
Client: St. Edward Homes
Main Contractor: PJ Carey
Quantity Surveyor: St Edward Homes
Structural Engineer: Manhire Associates
Value: £1.4M
Programme: 12 weeks
Scope: Guide walls, secant pile installation, pile
attendances and clearing of pile spoil.
Challenging Projects Require Innovative Solutions
Stuart Norman
Managing Director (Piling)
Stuart is a professionally qualified Civil Engineer with 12 years
experience at industry leading contracting companies, he manages a
core group of design engineers using their skills to the maximum benefit
of our Clients. He has extensive experience in the design and
estimating of a broad range of piling and foundation systems with a
particular interest in bored displacement piling. Stuart has also worked
overseas managing diaphragm walling works at a major inner-city civil
engineering site.
Responsibilities
Key
Competencies
• Excellent communication & leadership skills,
• Management of complex piling, groundworks and rail projects,
• Adaption & compliance with processes & procedures,
• Proactive problem solving approach,
• Management of relationships including 3rd
party,
• Understanding of key project activities and successful delivery.
• The day to day management of the geotechnical design resource
(internal & external as required)
• Help prepare and authorise geotechnical designs/solutions for all
tenders and contracts in accordance with the latest CDM
regulations
• Assist and check designs prepared by the design team
• Attend meetings and communicate design requirements to internal
and external project teams
• Ensure that the content of technical design manuals and technical
procedures are rigorous and fully communicated
• Help Keltbray learn from works on site and to communicate good
and bad experiences
• Attend technical meetings such as ICE, FPS, seminars and
conferences
• Give training both internally and externally
• Prepare and present articles and papers on technical issues
• Undertake technical audits
• Identify areas for technical training of design staff
• Lead the development of new products, systems and procedures
• Perform role as Delegated Civil Engineer assisting in the training of
graduate Civil Engineers
• To develop personal capability in all aspects of temporary works
Design Co-ordinator and later Diaphragm wall station manager for Rokin Station. Responsible for supervision and organisation of
all construction activities associated with the installation of 1200mm wide diaphragm wall panels installed to depths of up to 45m
as part of the foundations for the new Metro Station. Development of steering system for Hydraulic Grabs to allow panels to be
constructed to verticality tolerances of up to 1:400.
Rokin Metro Station - Amsterdam
Location:
Client:
Main Contractor:
Consulting Engineer:
Value:
Programme:
Scope:
Metro Station Rokin, Amsterdam
Amsterdam City Council
Max Bogl
Witteveen & Bos
£40M
3 Years
Design of deep foundations for 34 Storey residential and commercial development as part of the regeneration of Elephant &
Castle. 1500mm diameter Rotary Bored bearing piles under polymer support fluid, 45m deep founding in Thanet Sand. Individual
pile load = 12MN. Pile design to BS8004 and structural design to BS8110. Analysis of sonic logging results and polymer testing
procedures.
Location:
Client:
Main Contractor:
Quantity Surveyor:
Consulting Engineer:
Value:
Programme:
Scope:
Elephant & Castle – Strata Tower
Brookfield
Brookfield
n/a
WSP
£1.2M
10 Weeks
33No Bearing Piles up to 1500mm
diameter, 45m deep constructed under
polymer support fluid
Strata Tower, Elephant & Castle
City Road, London Location:
Client:
Main Contractor:
Quantity Surveyor:
Structural Engineer:
Value:
Programme:
Scope:
151 City Road,
London Soneva Properties
SGP
N/A
Curtins Consulting Engineers
£1.5M
8 Weeks
900mm dia Secant wall @ 1500c/c with
retained height 11m. 86No Bearing piles,
900mm dia 28m deep
Design of an 11m retained height secant piled wall, single prop at capping beam level. 900mm diameter bearing piles in addition
founded in the Laminated Beds of the Lambeth Group and bored dry. Piles and retaining wall designed to Eurocode 7. Preliminary
test pile and pile group analysis required to verify the design approach.
450No Diaphragm Wall panels,
1200mm wide with depths up to 45m
including glass fibre panels for soft
eye.
• Lee Cain (CSCS, IIF , PTS trained)
Contracts Manager for Keltbray Piling
Lee has over ten years experience in the construction industry gained
in piling, ground works and rail works. Lee joined Keltbray two years
ago as contracts manager and has managed projects in both the UK
and the Gulf region. He enjoys the continued daily challenges offered
by the multi-disciplinary projects Keltbray undertake.
Responsibilities
Key
Competencies
• Excellent Communication and leadership skills
• Management of complex piling, groundwork's and rail projects
• Adaption and compliance with processes and procedures
• Proactive problem solving approach
• Management of relationships including third party
• Understanding the key project activities & their role towards the
successful delivery.
• Ensuring the successful delivery of the project and that the defined
scope is delivered to cost and programme.
• Provide safe working conditions for all site operatives, visitors and
third parties
• Understand and implement the project and specific specifications
and deliverables
• Ensure that the projects, as well as Keltbray’s procedures/systems
are adhered to
• Oversee administration and record keeping for the duration of the
project
• Report to operations director
The redevelopment of a large commercial building. Employed by Sir Robert McAlpine, we were responsible for
the demolition of the existing building. A sheet pile wall was used as the retaining wall but the removal of the
redundant foundations was required before its installation. We were responsible for removing obstructions
including a layer of solid concrete, over 1m thick located roughly 6m below ground level.
Selborne House
Location:
Client:
Main Contractor:
Consulting Engineer:
Value:
Programme:
Scope:
Selborne House
Sir Robert McAlpine
Keltbray Ltd
N/A
100k
6 weeks
We were employed by PJ Carey the substructure contractor. Our scope was to install guide walls, install 450
linear meters of secant piling, pile attendances and clearing of piling spoil. The secant wall is said to be the
largest wall constructed using CFA techniques with a retained height of 8m. The wall was part cantilevered
using 750mm and 900mm diameter piles and part propped using 600mm diameter piles. Keltbray utilizes 2 high
torque Soilmec R625 rigs to execute the works and complete works in 9 weeks, some 3 weeks ahead of
schedule.
Location:
Client:
Main Contractor:
Quantity Surveyor:
Consulting Engineer:
Value:
Programme:
Scope:
375 Kensington High Street
Edward Homes
Edward Homes
N/A
N/A
£1.2M
34 weeks
Coring Works-removal of redundant
foundations.
375 Kensington
High Holborne
Location:
Client:
Main Contractor:
Quantity Surveyor:
Structural Engineer:
Value:
Programme:
Scope:
280 High Holborne
MACE
MACE
N/A
N/A
£139,788,88
4 Weeks
Design and Construction of CFA Piles
Subcontracted by Ballymore, we completed 436 piles of 450 mm and 600mm diameters. This included 3 crane
base piles as well. The piling platform was spread evenly across 3 levels of 7.00, 3.95 and 3.20 m OD. The strata
consisted of made ground over old dock remains & London clay. We installed and tested a non-working pile with
brilliant results. Moreover, 4 working pile tests were conducted on piles nominated by Ballymore and Tower
Hamlets Building Control. These tests were also very good to show that the pile design was apt for the strata.
Coring Works-removal of redundant
foundations.
Challenging Projects require Innovative Solutions
David Roy (MSc, FGS)
Proposals Manager for Keltbray Piling
David is a Geotechnical Engineer with 9 years experience within the
construction and ground engineering industry. Initially working as part
of a busy regional estimating team, David has built up a wide
experience of a range of ground improvement and piling techniques.
His technical knowledge, particularly in the design of deep foundations
and retaining structures, was further developed after working for several
years as a Design Engineer, leading the design development and
detailing of several major projects in London.
Responsibilities
Key
Competencies • Extensive knowledge of ground improvement and piling techniques
• Ability to organise and communicate within a project team
• Producing high quality bid and supporting technical documentation
• Assessment of tender enquiries and production of competitive
bids for bearing pile and retaining wall schemes
• Assist design engineers in producing efficient, value engineered
foundation designs
• Advise clients on value engineering options for foundation
schemes
• Regularly attend meetings with Clients and Engineers to discuss
and develop schemes
• Carry out tender pile and retaining wall designs to latest standards
• Attend industry events and keep up to date with new products and
techniques
• Maintain current customer base and ensure high quality of service
to key clients.
• Develop industry presence and market visibility
• Develop internal estimating systems to increase efficiency
Responsible for the design of deep foundations and retaining walls to Eurocode 7. Attended design team
meetings for 4months prior to construction to explore numerous value engineering schemes with the team.
Bearing piles up to 2.4m diameter, 65m deep, constructed under bentonite support fluid were required to
support structural loads of up to 40MN. Plunge columns of 750mm sq were installed to allow a top down
methodology to be adopted. Secant wall up to 1200mm diameter was designed to retain 15m deep basement
excavation in a single span.
100 Bishopsgate, City of London Location:
Client:
Main Contractor:
Consulting Engineer:
Value:
Programme:
Scope:
Bishopsgate, City of London
Brookfield / Great Portland Estates
Brookfield Multiplex
Robert Bird Group
£10M
34 weeks
Bid Manager for piling and ground improvement package for this landmark bridge on the London Olympic site.
The scope of work changed dramatically during construction, requiring detailed redesign and on-going design
development. Design had to integrate both Olympic and legacy mode uses for the bridge. Project won Best
International Project at the Irish Architecture Awards 2012 and shortlisted for the British Construction Industry
Awards 2012 and Prime Ministers Better Public Building Awards 2012.
Central Park Bridge – London Olympic Site
5-7 St Helen’s Place, City of London Location:
Client:
Main Contractor:
Structural Engineer:
Value:
Programme:
Scope:
St Helen’s Place, City of London
The Leathersellers’ Company
O’Keefe Construction
Robert Bird Group
£1.3M
16 weeks
900mm diameter secant wall retaining up
to 12m height. Temporary and permanent
bearing piles 600-900mm in diameter.
Lead designer for this project, involving installation of secant piled wall and bearing piles within and adjacent to
existing retained facades and a 13th century church. The façade retention system imposed a complex set of
design loads onto the secant wall in addition to temporary bearing piles. Stringent deflection criteria for the
retaining wall was required due to the proximity of St Helen’s Church along one side of the site.
338linm secant wall and152 bearing
piles including 60 plunge columns
constructed up to 65m depth
Location:
Client:
Main Contractor:
Consulting Engineer:
Value:
Programme:
Scope:
Queen Elizabeth Park
Olympic Delivery Authority
Lagan Construction
AKTII / Mott MacDonald
£1.2M
20 weeks
CFA bearing piles at bridge abutments, vibro
concrete columns supporting approach
embankments & reinforced earth retaining
walls.
Challenging Projects require Innovative Solutions
Keltbray Ltd St Andrew’s House Portsmouth Road Esher KT10 9TA | T 020 7643 1000 | F 020 7643 1001 | E
Stuart Norman, MD, M 07793 650 514 E [email protected]
David Roy, Proposals Manager, M 07827 351 495 E [email protected]
Charlotte Howe, Administrator, D 0207 643 1094 E [email protected]
www.keltbray.com