Friday 9 August 2013

Innovation Experience

To add to the previous post about innovation in architecture, I would like to describe some of my experiences working on innovative designs.  Two key projects I have worked on include the London Millennium Bridge by Foster and Partners (1998-1999) and the Halley VI Antarctic Research Station by Hugh Broughton Architects (2004-2011).

The London Millennium Bridge (left) by Foster and Partners
The Halley VI Antarctic Research Station (right) by Hugh Broughton Architects

Both were very different and both very exciting to work on.  For the London Millennium Bridge, I worked on the design of the main bridge section, the 'eye of the needle' connection to the south bank and the north bank connection, prior to Tender.  For Halley VI I was lucky to be involved from beginning to end - competition to completion.

The London Millennium Bridge
This was something of a unique project because it was more like designing a machine than a building. The bridge was set out in sections with movement joints at key locations to work with the structural requirements of the bridge.

Typical cross section through the bridge.
Everything above the circular steel sections was very carefully detailed
within the Architectural scope of works.
The structural tubes either side of tapered steel 'T' sections set up the structural base from which the architectural design was built.  The main elements consisted of the pedestrian deck, balustrades, uprights, and the bull-nose.  The bull-nose worked to provide the 'blade of light', which was a key part of the design.  My key roles at this stage of the project were to develop the geometry and setting out of the architectural components, investigate and research the selection of materials and coordinate the assembly of a bridge mock-up. 

Part section and detail around the bull-nose (blade of light),
base of the swan-neck balustrade and pedestrian decking. 

Geometry and Design with a Kit of Parts 
As a machine, rather than a building, the design of the components was carefully set out to achieve tight, accurate and consistent lines.  Adjustment was designed in to the connections with the primary structure to allow the positional tolerances in the architectural elements could be very finely controlled.  Although the bridge had to look simple and elegant, there was a fair amount of electrical cables to conceal, which required maintenance access.  Spaces were very tight.

Detail cross section showing proposals for access to the light-pipe and lamp housing. 

The light source for the blade of light was provided by a light-pipe.  This required access for replacing the bulbs, cleaning and power supply along the length of the bridge.  All this had to be neatly concealed, with the main bull-nose component movable in order to give access.  

The standard sections of the bridge: A kit of parts

We approached the design as a series of tightly coordinated components, and drew the bridge in this way.  This focused our attentions on how the parts would be made, prefabricated and fit together on site.  It also focused our attention to what fixing methods we adopted, access and where additional coordianation was needed.  

At this stage in the project the materials palate was slightly different to the final bridge.  We had a glass bull-nose, glass 'kicker' to the bridge edge, a teak deck with anti-slip carborundum strips and we were investigating rubber for the handrail.

The curved glass bull-nose was a challenge.  With Bowden Ide in East London we experimented with curving opalescent white laminated glass to the specific geometry.   What was surprising was that this was achieved with craftsmen in a workshop rather than technology in a factory.  The resulting samples were consistently accurate and the tight central radius had never been achieved before.     

Left shows some of the glass moulds.  Right shows gas pipes to the side of one furnace.
Bowden Ide had two glass bending furnaces.  Work was done by skilled craftsmen and not much had changed in 50 years.  Moulds were hand made and everything was layered in chalk, which acted as a release agent for the glass after bending.

The mould for the Millennium Bridge glass bull-nose panels

For the rubber coating to the handrails, we investigated companies outside the building industry to find a suitable material which would withstand UV degradation, a marine environment, vandalism from blades and cigarette butts. 

The metalwork was fabricated by Thames Wire (and they still show the mock-up frame on their website).  They were incredibly helpful with ideas and details for enabling the metalwork components to come together, to achieve the tight positional tolerances required to the architectural elements, and accommodate broader tolerances of the primary steelwork, including deflections.

The primary structure of the Millennium bridge mock-up made by Thames Wire.
Left shows the fixing components which interface between the primary structure and the pedestrian deck.
They allowed considerable positional tolerance in all 3 dimensions.
Right shows the channel and angle sections which sit over, to establish an accurate and true horizontal for the deck panels to sit on.   

These were very good (although small scale) examples of why fabrication specialists should be brought in to the design process at an early stage, so that architects and designers can achieve the best results with fully buildable proposals.  There was a lot to be learned from this process.

As part of the design process, and prior to fabricating the mock-up, several high-level design reviews took place within the office using material samples and full scale components, and drawings at either 1:1 or 1:2.

Ken Shuttleworth (Director) leading the design discussions.
Andy Bow (Project Director) to the left of Norman Foster.

The mock-up was assembled on the south bank of the Thames, near the point where the actual bridge lands, in front of the Tate Modern.  The intention was to show all the key components working.  This was why it was important to review the mock-up after dark, because the quality of light from the sides of the bridge, and on the deck was so important.

The mock-up assembled and ready for review.

At the end of this process, we had a final review of the mock-up before moving on to the develop the design further and prepare for Tender.

Familiar faces on the Millennium Bridge mock-up.
(Yes - that's me to the left with the double chins)

The Halley VI Antarctic Research Station
Halley VI, for the British Antarctic Survey (BAS), was an extraordinary project to be involved with, and incredibly exciting to work on.  I was involved throughout the project and took the lead on the design of the cladding envelope.  This included coordination with structure and services, and interfaces with the hydraulic legs, structural beams and service flues etc.  I was also site architect for the first build season.

With it being sited on the Brunt Ice Shelf, on the edge of Antarctica, there were a number of brief requirements which we had to work very closely to:

  • Although it is situated on the coast, the sea ice which forms in Austral winter prohibits access by ship.  The station operates for nine months through the winter typically with 16 crew members.  During this time there is no physical access to the outside world.  The environmental services and cladding envelope are two fundamental 'life-critical' parts of the design; to keep the crew warm and sheltered.
  • The station is subjected to one of the most hostile environments on earth.  Winds can be in excess of 100mph.  Temperatures have been recorded at -56ÂșC.  The lack of sunlight in winter affects the crew with SAD.  And the wind blows microscopic particles of ice (20-400micrometers wide) which ingress into any cavity and ice it up.  The site receives up to 1.5M of snow build-up per year, so that anything on the ground is buried - fast.  The station needed to be aerodynamic to resist snow accumulation.  The external envelope needed to be highly insulated, air tight and very robust.  The interiors had to be a 'home from home' - a great place to live.
  • Because the environment was constantly trying to bury the station, and because the Brunt Ice Shelf was flowing out in to the Weddell Sea at a rate of 400M per year, the station not only had to rise above the snow line annually, but relocate every 10 years or so.  The project had to be designed for mobility and the ability to withstand a reasonable degree of movement (twisting and vibration) throughout the modules.

This was all before we could start to think about the work of the scientists and crew.  As a result, the station is like no other building, and is the product of many innovation types.  There are so many innovations, I can easily list them here in relation to the types set out in the last post and no doubt I have missed a few.

Halley VI Antarctic Research Station

The solution was for a number of modular, ski-mounted buildings of a critical size and mass to enable them to be towed using site based plant (Caterpillar bulldozers) to new locations.  They are arranged in a line, perpendicular to the prevailing wind, to minimise the affects of snow accumulation.   Each module sits raised above the ice shelf on hydraulic legs to resist the environment's attempts to bury it and to enable it to annually rise out of the snow.  The station is arranged in two self-sufficient platforms, so that in the event of a fire (or other emergency situation) one platform can remain operational and act as a refuge until outside help arrives.  Inside, the station was designed to feel as comfortable as possible, with lots of different spaces and activities to engage people in and help oil the mechanics of a small crew working together over a long winter.

Procedural Innovation
The station had to be built over a number of Austral summers, with a very tight time-frame to build in.  Everything that was brought to site had to fit together neatly and without causing problems to the rest of the build.  We were very aware of this from the start of the design process and as a result, the design team (mainly architects, structural and services engineers, sustainability and fire consultants) formed a tight team structure where everything was very carefully coordinated, through design and production, right down to the fixing methods.  This close working arrangement was essential because of the tightness of the build.  Everything had a place and positional tolerances between disciplines and works packages were strictly worked to.

The standard module cross section shows that there is little room for error in the assembly of the components.  Each part is designed to work closely with its neighbour.  Positional tolerances were strictly controlled.  All tools, fixings and plant had to be included in the design.  The nearest point of contact is 400 miles away, so nothing could be left behind.

This close working relation ship extended to specialist suppliers of the prefabricated build components.  Specialists were brought into the design discussions early to help ensure the proposals were achievable and all the parts would fit together on site.  Some of the earliest discussions took place with FRP specialists for the cladding, hydraulic specialists for the legs, and pod specialists for the internal room pods.  This was extremely exciting and rewarding because the design developed at a tremendous pace and there was so much to learn from the process.  Detailed discussions with specialists involved design, testing and fabrication issues, and selection of materials.

Cladding sample made by MMS, South Africa.
Glazing had a heavy body tint because of the high light levels
in the Austral summer. 

Because the construction programme was so tight, with a rough 10-week window to build in each summer, weather permitting, everyone with a ticket to site had to work first and foremost as a site operative.  Any site based consultant roles, or note taking took place towards the end of the site shifts.

Here I am making notes on site during the first year Halley VI build

Process Innovation
Prefabrication played a key part in the design and construction process for Halley VI.  It was important to assemble the station in as few processes as possible to achieve the swiftness of programme required.

Four roof panels being installed in one operation,
with the use of a modular lifting beam to distribute the loads.
Photograph by Andy Cheatle

The extent of prefabrication was limited by several restrictions, but one in particular:  Between the cargo ship delivering the components and the ice shelf, everything had to cross a fragile strip of sea-ice with a bearing capacity of 9.5 tonnes.  Everything had to be designed and built to work to this one key restriction.  Weight played a critical part in the production of components for Halley VI.  During design and fabrication there was a considerable amount of analysis to calculate weights, and testing to confirm them.

Every item unloaded on to the sea ice could not weigh more than 9.5 tonnes

Science module relocation.
Movement of all modules uses standard vehicular plant kept at the base

Even as completed modules, weight was an important factor to the requirements of relocation and the annual process of raising the station out of the rising snow line.

Programme Innovation
Programme pressures did not start when the cargo ship arrived in Antarctica.  The pressure was on long before to ensure that all the parts arrived at the loading point Cape Town, South Africa in good time before departure.  Warehouse place was rented at the docks, and all items were carefully packaged and labelled so they could be identified and quickly located.  Components for the build were fabricated in the UK, Europe and South Africa.  Regular shipments were made from the Netherlands to Cape Town with items on a two-week cycle.  On this 'beat' the logistical team had to reserve the right volume of space on each shipment and ensure that items were available to fill the space.  Also, everything had to be sent south in time - nothing forgotten and nothing late.  Two weeks before departure, everything was carefully and tightly packed in to the cargo ship.

Buildability of the modules were tested in Cape Town before the parts were shipped to Antarctica

Both Standard and Central modules were tested in Cape Town 

To give some assurance that everything would fit properly on site, trial builds were performed of some of the modules in Cape Town.  This helped give clarity on the time it would take to assemble on site and whether additional tools or plant would be required.  Comprehensive sets of assembly drawings were also essential and shipped with the components.

Modules consist of steel space frame and superstructure, service cassettes, and hydraulic leg assemblies, floor cassettes with room pods over, and external cladding.  As much as possible was prefabricated. 

The unpredictable character of the environment meant that site work had to go ahead as quickly as possible because there was no guarantee when the weather would close in and stop the build process.

Every day is different at Halley

People Innovation
Although life at Halley consists of being part of a small crew in winter and a slightly larger crew in the summer (when the relief ship arrives with the a summer science and maintenance team, bringing supplies, food and chocolate), crews consist of science and support staff.  Science staff include meteorologists and earth scientists.  Support staff consist of mechanics, carpenters, electricians, plumbers, doctor and base commander etc.  It was important for the Halley VI design to help to integrate these diverse groups of people as much as possible to help create a friendly environment on the station.  This was done by planning out the station to make it as integrated as possible.  For the first time, scientists occupied the same spaces with the new science modules.  The large red central module formed the social heart of the station, the place where everyone eats, and a place for relaxation, recreation, work-out or study.

The fabulous observation point of upper level science module.
A great place to work 

The bedrooms (pit rooms) were designed to be comfortable but not comfortable enough for crew members to hide away in them for long periods of time.  The station was designed to encourage crew members to spend time in the social areas.

The Central Module recreation zone.
The social heart of the station.

Another innovation was to streamline the operations of the station, especially during the summer season.  Halley V relied on a team of steel erectors to adjust and reset the station on its steel legs.  Then, with the whole 50-strong crew working, the station is raised.  With Halley VI's hydraulic legs, the whole station can be raised by a small team much more quickly and efficiently, saving the requirement for up to a dozen people on site.

Some of the colours from our Spring palate

Because the station is isolated during the Austral winter, with three months of total darkness, we developed a number of strategies to combat Seasonal Affective Disorder (SAD).  This included daylight simulation lights within each bedroom (pit room) to wake crew members with a 'natural dawn'.  (Architects always think it is sunny outside, probably because they very rarely get out.  Most London mornings are a kind of a dull grey).  We also enrolled the help of colour psychologist Angela Wright at Colour Affects.  She assisted us with a palate of harmonising Spring colours, designed to add vibrancy and life to the station.  Colours were also matched against activities (blue for science etc.) to help locate people and set moods.

Price Innovation
The budget costs for the station was tight.  This was not helped by the logistical challenges which came at an unavoidable premium.  One advantage of the modular approach to the station was that the brief could be re-assessed as the project developed, and where necessary the number of modules could be reduced.  The project remained essentially the same and the Client has the option of adding modules back in time, as funding allowed.

The visualisation at competition stage shows three more standard (blue) modules than were eventually produced.
The Central module (red) was also reduced in size.
These reductions to the scheme (approximately 25%) did not significantly affect the overall concept.

Product Innovation
There are lots of neat developments which can be considered product innovations and it is quite amazing that we were able to develop them for an Antarctic environment.

The design and development of the cladding envelope was a very involved process.  As a life critical item it was essential that it had to be robust, airtight, able to move with the dynamic performance of the station and resistant to fire.  The cladding was developed closely with Sean Billings of Billings Design Associates in Dublin, Ireland and Leon More Snr. at MMS in Pretoria (and Cape Town), South Africa.  The cladding envelope included the panels, insulated external doors, flexible module links, windows, areas of specialist glazing, junctions, gaskets, fixings and anything which affected the integrity of the 'skin'.

With Titan hydraulics in Halifax, and the engineers we developed the hydraulic leg for the modules.  Cladding around these moving parts to ensure a tight seal and designing the leg cladding around the cassette and structural connections were our key areas.

The first hydraulic leg cassette being tested in 2007.  The power pack is on the left of the image.
The leg cassette is upside down because it was not mounted to anything and was top heavy.
The leg cassette was huge and dominated the factory.  One of 34 to be produced.
When we first say this we began to realise the scale of the project we were working on.
We played with travel speeds and positional accuracy that day.

With Octatube, we developed curved roof lights for the central module, developed around aircraft cockpit windows.

The Central Module's cockpit rooflights made by Octatube

Between Okalux and MMS we developed a glazing system for the Central Module front wall using a combination of Aerogel glazed panels, triple glazing and a structural FRP frame.  The MMS framework was special because it also provided all the structural requirements to this large area of the module.  It acts as a single structural surface.

Central Module main glazing being installed on site

The FRP cladding envelope took a lot of time to research and develop.  It had to be strong and durable to withstand the hostile environment outside; air-tight, resist to abrasion from wind blown ice, highly insulated and able to cope with sustained buffering from strong winds.  Internally, it had to have excellent fire resistance.  In construction, it had to come to site as a single layer component and assemble quickly, with as few joints as possible.   The cladding junction took a lot of investigation, research and testing, first with gaskets, and then with a cover strip.

One of the first drawings for the assembly line process.  This was late in the competition stage, but the assembly process fundamentally remained the same with steel space frame and superstructure, prefabricated floor cassettes and room pods and cladding.  At this stage we were looking at timber SIP with an architectural finishing panel over the top, similar to the solution at the Amundsen Scott South Pole base.  This was a two-stage process.  Our final FRP solution is a single complete skin and removed the need for this second step.  

One of the first sketches I did for the FRP cladding to Halley VI

I developed the cladding design at Hugh Broughton Architects with CAD and hand drawings

Final cladding detail to the standard modules.  Cover strip external junction (top) with two more fixing lines behind, with a very tightly sealed junction to ensure no spin drift ingress.  FRP tolerances were very precise.  Zone for steel structure behind.  Cladding mounted on rubber anti-vibration 'rubber shock mounts'.  Separately supported line of internal finishes (bottom).  Overall thickness from inside to outside is around 430mm with the cladding thickness being 215mm. 

Rubber 'shock mounts' similar to those used for Halley VI

MMS performed some in-house tests on their panels in Cape Town during production.
This one to a roof panel.

Perhaps the most important product innovation of all is the idea that Halley VI is the development of a new building type.  All of the individual innovations listed here add up to provide a building solution which provides something very novel; the first fully relocatable research station in Antarctica.

Halley VI after it's first Austral winter

Useful references (for adventurers):
  • BAS blog on the Halley VI project; design, prefabrication, shipping and site assembly
  • BAS web site on Halley VI
  • BAS jobs