An Architect’s Role on Bridge Design by US Group of IABSE
Thursday, 25 April 2024, 13:00
Speakers: Ben Addy and Ezra Groskin (Directors at Moxon Architects)
Moxon Architects have spent the last 20 years developing relationships which have led to fruitful projects and a thriving practice. From their portfolio, bridges stand out as they are experienced by the widest audience. However, the practice applies the same philosophy to all its works across sectors and scales. This diversity is intentional, bringing a fresh perspective to every project.
This talk will highlight a specific thread running throughout Moxon’s portfolio. Economy or ‘doing more with less’ is a principle they apply to the design of products, buildings, public spaces, bridges, and infrastructure. While this ethos predates the environmental challenges we face today, its importance will continue to grow as they contribute to a more responsible built environment.
This philosophy extends into less tangible/quantifiable areas of their work. A range of projects will illustrate its influence on aesthetics, technology, and manufacturing methods. All of this couples nicely with Moxon’s engineering sensibilities and an eagerness to collaborate with like-minden professionals.
okay all right sorry for the delay um we’re about to begin um thank you everybody for joining us we have a a full house here and then a Full House online uh my name is Paul Skelton I’m the vice chair of the US board for yapi and we’re very very happy to be uh hosting moxin today for their presentation which I’m certain you will certain you will enjoy um a quick note about um iapi um yepsy was formed 1929 um had 49 members and and 14 countries uh the organization now which is focused on the advancement and furthering of uh Structural Engineering worldwide both in buildings and bridges um is 300 3,000 members strong with 100 countries and the the the US uh uh contingent is is growing and we we try to support uh events like this and others through the year and we are very interested in having new us members especially younger members uh to investigate the the organization and and potentially become members um with that I’m going to hand it over to to Ben and Ezra of moxin and thank you very much that’s brilliant thank you um yeah thanks for that introduction I’m gonna um I’m having to use a mouse to control the screen and then my other hand control the laptop so bear with me if I get in a bit of a tangle but hopefully I’ll be able to kind of write it as we go through um so my name is Ben Addy I’m the managing director of Mox and Architects were based in uh London and also in the highlands of Scotland quite unusual as a practice to have very Urban location and very rural location um we’re also a very unusual practice in that we do conventional architecture so buildings and product design and what have you and you’ll see some examples of that but we also do bridge design which is obviously the reason why we’re in this room with you today and key to that is my good friend and colleague Ezra brosin here who shares a background in bridge design and Bridge architecture um with me so don’t if you want to add a few more words yeah as you you you might recognize from acent I’m originally from the US so this is sort of like coming back for me but I’ve work been working in London for 15 years kind of exclusively designing Bridges and then I joined Ben about eight years ago um to continue that work but um my special to be in a a small practice that does Bridges and buildings which is a balance I was looking for and I think you’ll see kind of the whether we’re working on a bridge or on a building we bring the same kind of interest in design and interest in solving puzzles and all and interest in how things are built all these things you you you’ll see through the lecture but those are things that are important to both of us um by way of um yeah introduction um well first of all thank you very much to Hardesty and hover and Paul for hosting us here today um and you know what a wonderful place to be I mean we’re like I say based in London and and the Scottish Island so being in New York for a week is a really kind of radical and welcome change um this is the slide that I used to actually um introduce um an i absy lecture that I gave last year in central London that annual lecture for the for the British or the UK group um and the sub title for this should be How To Lose Friends and alienate people um I’m in a room full of bridge Engineers um and yet uh no one should be interested in the design of bridges um the reason I showed this slide is for the last 20 years or so I’ve been taunted by um university friends of mine who are Architects but um it’s fair to say they don’t share the same passion for bridge design that Ezra and I have um but what they always miss out is the second part of the quote which is um the punchline really which is worry about the problem and you’ll find the solution it’s a great quote um it’s a valuable provocation for um for any designer it’s just unfortunate that bridge design is used as the kind of the basis for the metaphor um because I think the bridge designers whether from an engineering or an architectural background the first and foremost problem solvers doesn’t matter about you know the discipline you’re in we’re all together as a single team working on the same kind of ultimate objective I should also say that this gentleman in the left hand corner um is uh probably he’s been called the most famous architect or rather the most important architect of the 20th century that no one’s ever heard of it’s a guy called Cedric price and I’m going to come back to him in a moment um but first of all just want to talk about um probably the most important diagram uh of my professional career and probably everyone in this room in fact so um this is the hockey stick which doesn’t need any introduction I don’t believe um I was in my RBA part one so the beginning of my undergraduate at University in Edinburgh um when this graph was produced now it shows the global temperature variation or anomaly plus or minus one degree for the last 1,000 years so the last Millennia um and of course the implications of what it Des what it describes are so much more profound than just a change in temperature um it’s the defining image of Our Generation and the context in which all of us as designers are working back to Cedric price so I said that he was the the most important architect you’ve never heard of he was a teacher and a provocator um he taught at the architectural Association in London um he did lots of unbuilt projects from a thing called The Fun Palace in East London through to um various kind of sorry I’ve got caught up there um through to various structures which were built not many and this is it most famous uh built work which is the Snowden Avary at London Zoo uh it’s named for the client sponsor which is L Lord Snowden who’s a photographer um but it was designed by SED price with an engineer called Frank newbie who’s a very famous kind of mid 20th century English engineer um an extraordinary engineer in fact now the Avary employees principles of Tegrity so much like an earlier project by uh Frank new in London called the skyon um so it’s using tension members and compression members to try and make as as light a Spector as possible um and in fact Cedric price um although he probably wouldn’t have admitted it at the time given his quote about bridge design was operating in the same way that a bridge designer operates in designing this building so looking at lightness looking at efficiency leanness making do with minimal materials to achieve an extraordinary building in the end Joe’s pizza is here um now the other thing to say about SED prices and you can probably tell from an image like this is that although he isn’t that well known he’s been enormously influential in generations of Architects and Engineers that came after him so uh in New York City here you’ve got obviously buildings by Richard Rogers WTC you’ve got Lord Foster buildings all over the place you’ve got Renzo pianos uh New York Times building all of those buildings follow from the teachings of Cedric price back in the 50s and 60s so there’s a kind of a an effect that he has caused that is very much present in today’s architecture and structural design and I think the effect is something to do with economy and now we’re going to sort of talk about some of our work and what this means to us as as Architects and designers um it’s how Ezra and I often talk about the work of our practice um it pretty much goes unsa in our studio but when we look around what we’re doing both as individual designers but also collectively as a practice um it’s the Common Thread so it doesn’t matter whether it’s a building or a product or a bridge or whatever is this idea of economy that is kind of stringing everything together um it’s not about being kind of mean or parsimonious you know it’s about um efficiency and elegance if that makes sense um and I think that it’s fair to say that we’ve learned that culture from bridge design so from working with Bridge Engineers that’s where we get this idea of economy from because in bridges economy is what you’re always striving for the best bridges are always the most economic in terms of material use slenderness lightness Elegance all of that so we’ve sort of split this presentation into three ways of thinking about economy now the first one is economy of material which is kind of obvious is using less material to achieve a particular objective um and it’s kind of axiomatic for bridge designers it’s part of our kind of philos in our culture that we’re all working with um the second one is economy of action um which is a little bit more cryptic this is something that we’ve come up come up with ourselves but basically as a designer you sort of pick your battles you what’s important you prioritize where you’re going to focus your energy and your your your kind of effort um and in our case as as Architects it’s about targeting those aspects of a design that can Elevate what’s basic and functional to something really kind of valuable and beautiful um so you prioritize your approach approach um and then the third and final kind of mode of economy if you like is economy of purpose um now this can relate to a detail so I think everyone here as designers will all know the satisfaction when a design can do two things at the same time you know this idea of killing killing two birds with one stone um so on this bridge in fact which we’ll talk about in a moment um the deck is also a badier so it also of is is for getting from A to B crosses um the river temps but it’s also a means of spectating on the Oxford Cambridge boat race so it does these two things um and that’s I mean what’s one one of the most wonderful things about bridge design is the instrumentality so like a product it it has to do a thing a particular thing and every bridge in the world does a particular thing and it does it in common with every other Bridge it got from A to B or to C to B and E as well maybe whereas buildings are quite complicated things you know they do tons of stuff all piled up on top of each other and can become quite complex objects whereas bridges are this instrumentality means that they are pure design you still worry about context you still worry about history landscape all of that but they’re ultimately at the end of the day they’re doing a very pure thing um which is a really kind of beautiful way of thinking about design so that leads me to our first project um which is not a bridge um eventually I’ll get to the point and start showing some bridges um but but it was designed with um crucial input from an engineer um actually in this case from kovi in London now we work like I said we do buildings and all that sort of stuff and products like this but invariably we’re working with Engineers who have a bridge background and that’s really important to us um now this glory is photographs by a UK called Tim saw um and it’s of a drinking fountain that we won in competition for the Royal parks in London it has a New York connection because um it was sponsored by Tiffany Jewelers um and now Tiffany have paid for these things all over London’s Parks so they’re they’re all over the place in in the rural parks in London tiny little things I think that that’s big but um you know blinking you’ll miss it but it’s like a calling card they’re all over London and most of them have our name on it which is rather nice um now it was one in like I say an open International competition um and it’s the first of two examples of industrial design that I’ll share um because it encapsulates this idea of economy of purpose so it does the thing that it’s supposed to do which is deliver clean hygienic water um but it does several other things at the same time um to all manner of users K9 and otherwise um so there’s a dog bowl at the base which is the Overflow from the top so it drains down into this dog bowl at the bottom before it then goes into the into the sewer system uh that’s also a trap so if someone drops their wedding ring in the top it go down the funnel and it’ll pop out the bottom into the dog bowl they might need to clean it afterwards um but it’s this idea of like I say achieving several things at once it’s also a Ballard so this thing can be used as a vehicle or restraint Ballard um so that the way in which it connect at the bottom is kind of integral to that um so it can stop a it can stop a light vehicle um and you can here see the kind of the refinement and the geometry is really important to us you got this one single form which you know it’s the mounting for a foret for the tap uh it’s a bowl for splashes you got the drain you’ve got the sleeved connection from the base excuse me um the design is tap agnostic so you can fit any tap that’s available on the market onto this thing which is really important for longevity so that you know tap technology develops you can put a new you know infrared tap on the top or what have you and again that’s something we’ve taken from that architect at the beginning Cedric price who had this idea of flexibility in use which is really important um and then we’re interest in Aesthetics as well so the form of this thing is really important um it was one of our first uh foras into rapid prototyping which is obviously common in what we all do now but this is like 15 years ago and this was kind of Novel for us um you got are you able to yeah that’s probably better yeah right we’re going to team effort this it’ll go a bit quicker now um so this is the actual Master part that was milled from the material that then went into form the last wa casting so this is in a bronze Foundry in Wales in the UK and you get this incredible kind of beautiful bronze um piece that comes out at the end of the casting process you polish it up here’s our first customer in the Royal Park um and then it patates over time so the weathering the way this material behaves over time again this comes back the bridges it’s exactly what we think about all the time um and then here’s one of them outside Kensington Palace um I think there’s about three or four in Kensington Gardens now but like I say they’re all over London the dog’s just been at that one five minutes beforehand um this is our first Bridge of the afternoon so that’s our kind of design philosophy in a nutshell through that product Pro product um and I think hopefully yeah there we go so this um yeah Dukes Meadow Bridge so this is um a foot bridge in West London that we designed with kovi so we work with various engineers and we’re really Keen to be working with yourselves uh both in the UK and IDE do in the US um in the near future but you you’ll hear me talk about various Engineers that we worked with throughout because it’s always a team effort you know it’s never about the architect says this and someone else has to make it work or vice versa it’s you know always a team effort and this bridge runs doesn’t go across the tens of kind of runs alongside the tens and it fixes a link of what what was a previously broken uh T’s path that runs along the river um and the second of our bridges to do this actually after another one in East London but here you can see the parit is the primary structure which allows us to kind of thread this thing underneath the existing bridge and a fil maintaining clearance between high tide and Headroom underneath the arch of the bridge um you can see in the plan here how I I mentioned about the baders on the bridge this is the one where just the widening of the corners there enables people to kind of congregate um congregate on the deck see get this amazing view Up and Down the River um it’s also perfect location to watch the uh the Oxford Cambridge boat race this isn’t the boat race these are anths um but you get the idea you know it provides this new new new space in the city just from otherwise a very functional uh link along the river more views of it so I mean you obviously identifi this as a it’s a very very simple truss but we’re using the truss as the handrail and the restraints all at the same time so the structure the parit everything is one piece um which again is about efficiency um now each part of the bridge was brought up the TS from from til docks in East London um but it was floated above the peers and then as the tide so the tens is tidal at this point so as the tide rolled out the deck was lowered onto the peer so you let nature do the work which is you know the most efficient thing you can do um of course it’s not quite as simple as all that because while we’re relying on gravity we also relied on a particular um bit of temporary works that was designed by the engineer guy called Chris Murphy who designed this three-part location pin which is a component on top of the pier without which this bridge would not have ended up in its Perfect final location um it’s somewhere in this Photograph and no one who uses the bridge is aware of that but we’re aware of it and if it wasn’t for that locor pin Bridge would have been very different and again these are engineering and Bridge engineering particulars full of these kind of stories of ways of achieving things in construction that could not have occurred without that kind of Genius going on um so it’s a privilege to be part of that kind of conversation with Architects um now next bridge that we’re going to show does legitimately go from one side of something to another this case it’s the um raw Victoria dock in East London um we love getting involved in drawings like this so this is a drawing where we’re looking at the constraints uh of a structure um we’re looking at um navigation channels that we need to maintain the landing points there’s discussions with both Structural Engineers civil engineers and also mechanical electrical engineers all involved in this one drawing this is where we’re trying to tease out as a team we’re working on this drawing together to work out what’s the best alignment for this bridge um you can see there’s Excel Center at the top there’s a new development at the bottom basically going to be thousands of new homes on the bottom right hand corner big development going on and then in the top left hand corner is where there’s a a new train station people need to get from one to the other so that’s what this bridge is for so a to be straight route would seem to be the most logical thing however the blue lines in the middle we need to maintain an infinitely High navigation channel so we need an opening bridge if we have a diagonal line across that channel then that’s quite a long opening section so you want to come a square as possible to it as perpendicular as possible to minimize the cost and the cost that the opening section is way more than the cost of the back span so hence these kind of studies this sort of exploration and eventually we arrived at this kind of form which although it might seem inefficient is actually not that much longer than a straight line but crucially it has perfect or nearly perfect um perpendicular open section which keeps the cost down so this structure um was granted planning permission earlier on this year and we’ve got the contractor is on board now so I think construction is going to be starting this year this year at least um and you can see here the opening section that we’re talking about so very very straightforward I mean I’m in a room full of the absolute experts in opening Bridges so I need to be careful what I’m going to say but um you can see that it’s a twin bascule um the the each Leaf of the bascule rests on the pier itself so you don’t need to worry about locking pins in the middle necessarily um the axis of rotation is this is the axis of the uh span reading up to the opening section so it comes quite a surprise when this thing opens it’ll have this kind of twisting effect but actually the mechanism and so forth is really sort of straightforward and simple and simplicity and and kind of appropriateness and pragmatic kind of approach design is really important um and for as the joy is in the detail so this is where you can see these are the actuators so the Rams uh in this image on the pier the little orange bit is where um it rests kind of the bearing when it’s in the the closed position um the bridge is part machine and it’s quite enjoyable to sort of Express that the design doesn’t hide it you can see the kind of the S curving traj C of this bridge um the the VP in the foreground um it’s a bit of vertical curve so as you go onto the bridge You Are Climbing and then you drop down the ends to allow smaller River craft to go underneath it um so you’ve got this kind of the um the that’s the new development in the background it’s just got um it’s actually quite similar to hugs and yards in a way in terms of the focus on Landscaping we’re taking the landscape finishes all the way across this bridge so it’s an extension of the urban realm um but you’ve got this amazing machine under this okay so just briefly on another opening bridge now this time is in Dublin in in Ireland um where the the port has got this amazing uh boom in business after brexit so once the UK left Europe instead of All European stuff coming into the UK and then going to it’s bypassed the UK and goes straight for Dublin so the port is incredibly busy and as part of that um they need new Road Links across the river um which need to be opening links because uh all the other Bridges up the liy are also opening um so you can see here it’s a it’s a basuel bridge with a with a counter lake so again nothing unfamiliar um and there it is in the open position but sharped amongst the amongst you you may have noticed that there’s something slightly unusual going with the um the pivots particularly of the counterweight arms so that gives the game away so this is another piece of kind of ingenious design and uh there’s one of our colleagues in the office at chck called Richard the bridge which is the most appropriate name for a bridge designer um and he he had this idea that if we actually introduced another fulcrum so if we introduced another pivot so another of pivots and brought the the fulcrum of the uh the counterweight forward of the hinge of the deck then that would mean that in the opening sequence the the effect of the counterweight would be felt far earlier in the opening sequence than if it were just fixed like this does that make sense so it’s actually a more efficient in terms of energy is more efficient uh opening sequence for the bridge um plus obviously you’ve got kind of the drama of this sort of scissor movement that’s going on um and yeah I mean there’s always this kind of joy in the detail of how these things all come together I mean there’s a there’s a whole we could spend a whole afternoon talking about the the the design of this um you it’s making sure that everything nests perfectly again this is the stuff that you guys do for your is is there rot in The Wire yes there is yes there yeah so it’s a little bit more um now in the closed position um the counterweight is obviously also a demonstration of mass and energy you know hung above the um the the carriageway uh forming a portal so it’s was important this bridge is a gateway both along the river but also a Gateway along the bridge uh for the port now where we are I think we are still exploring the use of granite as the material for the counter R so rather than using steel or concrete um there obiously carbon savings to be had there um so we’ll see where we where we get to with that um so the second category was economy of action um and I think for Architects are there any architects in the room one two okay there’s at least four of us who are next um and I think that um that that this is the bit that it’s certainly in terms of bridge design this is probably I mean I don’t like to sort of divide it into disciplines because I think it’s kind of false but this is probably the bit where as an architect you probably do have the most potential for impact in bridge design um and it’s about this idea of sort of picking things that can just be turned or twisted or changed just subtly and it can have an an enormous impact on the the appearance of a structure um so the first example here is um this really modest foot and cycle Bridge called hamway near Worcester in the Midlands of England you can see even from the the drawing it’s a very straightforward brief it’s basically just get around a busy roundabout and in the elevation at the bottom you can see it’s just a very simple tide Arch it’s no different to um hundreds of other bridges that cross the trunk of England England excuse me um and indeed the brief from the client was that it should be like uh other similar Bridges but what makes this not normal are some very very simple modest uh moves in the design that elevate the appearance above its more functional utilitarian Brethren um firstly you can see here that the parit lean in the direction of the cycle traffic so this is a cycle Bridge it’s got hundreds of cyclists today using it as part of a national cycle route um and just that subtle shift changes the perception of the bridge that someone has thought about it there’s some craft in it it’s relating to the direction of travel um the approach BS couldn’t be more simple so that’s on the left hand side here it’s the approach biod doct it’s just a series of columns and some beams and then some Edge beams um and then on the right is the arch truss um but to unify them you can see the outer cords the square Hol sections have been rotated through 45° so very very simple move but when you see it in reality that has changed the appearance dramatically so you get this kind of thin Edge you get light and Shadow and the way in which all these pieces come together um takes away from what could otherwise be quite a dull structure and then these two things come together at the um at the springing point of the arch or the main stand on the right and then the vi back stand on the left you can see where these things don’t quite meet one another um so again it’s about expressing the difference between these two parts of the structure that it’s doing it in a really kind of we think beautiful way hopefully hopefully you’d agree um that it’s you know somewhat more elevated than a a basic structure um now the same team again working with um this again colleagues with KI on the bridge near Worcester um this s across the river aen um the way in which landscape and bridges come together really important I think for all of us as designers um the bridges can have such a important impact on their settings that you always need to be sort of considering them in in landscape terms so the other end of the spectrum um I was going to talk about three of our viods for hs2 um HS to is the UK’s highspeed rail network currently under construction um and we are part of one of the three very large contractor consortia um building the line so ekb iage Kia foval ban that’s some of Europe’s biggest construction companies they’ve had to team together to build this one pit bit of the line um and then we’re working with arcadis setc kovi as engineers and then there’s little world do at the end and we’re like the smallest possible Cog in this absolutely enormous um enormous machine um but our clients to Great to their credit that they have brought Architects and our engineers and pushed us right to the front of the process and made us kind of instrumental in getting consent for all these structures um I don’t know how many of you have seen Ian F’s Ted Talk on bridge design so former president of um institution of structural engineers in the UK and chair of the UK’s I absy group um he gave a really brilliant talk and um in it he said that a badly designed and executed bridge is nothing short of an act of vandalism on the landscape and um two of our viaducts that we doing for hs2 are located within What’s called the Chilton’s area of outstanding natural beauty so I’ve had Ian’s words ringing in in my ears um for several years now as we’re designing these structures um now one of these biod ducts is in the mum Valley which is this kind of you can see in this topographical map you’ve got the um the kind of pronounced diagonal line there is the CH What’s called the chilon escarment so there’s a series of chalk downland Hills really really really beautiful you think of England you’re thinking probably of this landscape um and HS through the railways cutting through this kind of narrow Gap that you can see near the town of Wendover we’ve got a series of VOD ducts that kind of help to carry the Line North through that Gap um the first of them being W of Dean so you can see here um parallel lines of communication you’ve got a railway a road there’s high voltage lines power lines everything kind of runs through this Valley so it’s no coin no coincidence that the railway the new Railway is coming through here as well and what this diagram shows is the position of the viaduct which is the solid orange line and then the kind of gray out area to the right with that Contour so that Contour is the at the same height above sea level as the bridge deck what that means is that if you’re in the gray area you’re looking down on the structure and if you’re in the white area you’re looking up at it but against the terrain so this is not like you know you think about a viod like meow which is on one of slides at the start you know amazing structures that stride across the landscape against the sky this isn’t that at all you this is a Viaduct that um is sitting within the landscape and that has a really profound impact on how you design such a structure and what’s important um so you can see here that it’s a pretty simple design um it’s a composite or a double composite viod duct so using steel and concrete in concert um with below deck structure now during the the petitioning stage is what we call it in the UK but when when hs2 was a bill in Parliament before it was made an act um The Campaign to protect rural England who a very powerful stakeholder in the UK um said that the design of this biu would be a litmus test for the quality of design on hs2 as a whole so again no pressure um so bearing that in mind with all the things that you think of as a brid designer in terms of how this thing sits in the landscape the spance depth ratio how is it going to respond to the land form can we keep this thing nice and symmetrical or we do something like this so This is actually the employer’s reference design that we given this part of the brief and you can see that this bridge could be anywhere um it’s asymmetric it doesn’t really fit the landscape the the abutment so really crude there’s no real kind of sympathy for what’s around it so the simple thing is we bring some symmetry you rearrange the the the structure you reduce the length of it make savings there carbon cost savings um simple things Shing the structure at one end um reduces cost obviously um but then even better we can reduce carbon if we can replace that spam with in Bank L and you’ll see that we’ve kind of eliminated the CL from the abutments by basically turning them into a socket in the hillside so a sleeve so the bridge disappears into a sleeve see in the animation here so although this is a really simple structure it’s just a led up sitting on peers if you focus on these details around you can see the peer heads as well which extend beyond the bearing shelf focusing on these details you can Elevate this thing from being what could be quite crude quite kind of rude intervention in the landscape into something really kind of simple and elegant and the color of the steel the way that sits against the rural landscape the way in which all the land land form is dealt with these are balancing ponds at one end you know all these things come together it’s just it’s not so much about creating a statement or an icon or anything like that it’s about just being kind of risp minimal polite you know worrying about back proportions you can see these peers um where we have sort of extended them beyond the bearing so this is about [Music] um accentuating the bright parts of the structure so we’ve got the parit at the top which runs across the valley and then we’ve got the peers beneath and you bring the two things close to one another and it helps to make the the structural beam which you can see in that image is really deep it helps to make that recede a bit because you’re pushing the bright Parts out in front so it’s a kind of visual trick um you know the sort of thing that Renaissance painters used to do a lot with the dark and light and the paintings um how am I doing for time okay we’ll go quickly through this one this is another another biod do which um we some of the people in this room will recognize it do you want to talk about this bit so we were we were really really lucky to be working on this uh structure with um theom and per and um Paul Van Haagen um this is the next vodu north of previous one you can see it’s following some of the same principles uh in that it’s a composite structure um but but uh it’s in a very different setting even though it’s quite close by it crosses a road a railway another road all in a really tight space and it does it at a really pronounced skew angle which means that we’ve got longer spans this thing is not about the appearance in elevation as wend over was because it’s sitting in this kind of hollow in the landscape a little knot in the landscape um behind screen by trees and rest of it um but in close to you’re the public road a very busy road goes underneath this structure so the appearance of this thing close up and in the oblique view is really important um what was interesting is the contractor uh wanted to be able to launch his deck um with his uh formwork in place so at w of De deck is launched or sorry the beams are launched and then uh a formwork traveler goes across it to install the deck on top here he wanted to be able to roll the deck out with the formwork in place you could quickly put a slab on it and then use it as a hall route which is a kind of constru construction issue but from our point of view there a great opportunity for working with can levers in order to achieve that working with yourselves um to to to achieve that end and it means that you have a structure which is um to go again um really kind of expressive in the detail now this isn’t this hasn’t come from a kind of um some sort of abstract idea or something that’s not related to the place or the structure this has come from a requirement of the structure and yet this is what provides the kind of the P aesthetic of the viodo so then the third biod doct that I was going to talk about um it’s just to the north again very different land form um it’s so low to the ground it’s really an elevated Causeway rather than a a viaduct in a way um you can see the cross-sectional form is very different um and without going into the whole kind of story of this particular structure um what’s interesting about it is that the entire thing is prefabricated so it’s an entirely preast roduct so it’s one kilometer long and every single component um is pre-cast and brought to sight like a gigantic Lego set um so there’s there’s very very little by way of um insitu concrete work on this structure and you can see some of the visual things that we’ve been doing with the other structures are also at play here in particular the way in which the pier projects past the bearing it masks the bearing um you can see the peers arriving on side like last year and again this form isn’t just willful it isn’t just about doing something that looks nice um that projection uh has a piece of Timber sacrificial Timber stuck to it during construction so that as the beams get lowered in this forms a guide to push the beam onto its bearing that Mak sense so that in in so doing it removes temporary works from it so it’s again about simplifying the construction process the the viaduct itself helps to build itself in a sense oh gosh this not my holiday snaps um so this is um this is actually I’m going to do my bit of scotch tourist board so this is um uh the view from our studio in SC um and talking about landscape and those previous biod dos landscape is how we also approach buildings as well um it’s the most important consideration um you have this incredible landscape in the kangs it’s like a bit of subarctic thundra sort of ships across from Scandinavia and drops onto the UK um You’ve Got Sublime so in the Victorian terrifying sense uh absurdly picturesque um to kind of chocolate box um and we’ve got a building our building our studio sitting amongst all of this um so what does it mean to position a building in in this kind of location well it means exactly the same as to position a viaduct in the ch’s a these are very precious Landscapes uh they’re under pressure world over so to do any development in these kind of locations you need to be you know really thoughtful and considerate as to as to what you’re doing so here we really using the the form of the landscape to drive the design of the building so the stud is actually in a disused quarry so it’s in a Brownfield site we’re taking the Contours of a quarry and using that as the generator of our plan so you can see the elements of our building coming together these are two chimneys for fireplaces so they’re almost like the peers of a Viaduct um you can see our Studios at one end and then we’ve got a public Cafe at the other end and then the building kind of is built up around this kind of Armature like I say is derived from the Contours of the site so it’s a really kind of beautiful place to to work very kind of calming atmosphere and like I say it used to be a quarry so it was full of really badly contaminated land even though it’s surrounded by this beautiful Woodland we’ve cleared up the contamination got the pond in the middle and the way in which you know we then seeded it and we got trees and what Havey that are coming so it’s now an extension of the natural landscape around it and again there’s a lesson there in bridge design because as Bridge designers we’re always thinking about the landscape around it you know it doesn’t matter whether you’re an engineer or landscape architect or whatever it’s always about the setting as much as it is the structure um and how things kind of connect through setting I’ll skip through these this just talks about how building mass is is quite a big building but you’d never really perceive it as such a big building because you look up the roof and you never get a feeling for how how tall it is there’s another video of it so because we have the cafe on site um this is obviously a very quiet day normally the cars are like double parked and there’s hundreds of people up the cies and whatnot and they all come wandering around our building because it’s kind of an open site so we’ll be working away on some nice Bridge somewhere and there’ll be people at the window peing through like this and then people go up onto the roof Terrace at the back and they’re peering down at us like this it’s like we’re in a kind of golfish bowl um but no it’s a lovely place to lovely place to work um back into Bridges because that’s kind of why we’re here um we have done some bridges in Scotland as well so this is um in the foreground this is the G Shield Bridge which was built in 1750 this a scheduled ancient Monument whistic building um really kind of precious structure it was built by I don’t know how much of you know about Scottish history in the Jacoby Rebellion Outlander there you go so so the bades won and they built this Bri to to keep the Scots under control and it’s a really I mean you can see the arch it’s a gorgeous gorgeous bit of masonry um and our new bridge is uh basically taking all the vehicle traffic because that was designed for H and carton with soldiers and um not buses and lorries so we we built this new bridge alongside to to divert the traffic seeing the foreground there and then the old bridge is now a kind of almost a museum piece it’s for tourism look at this beautiful thing um very happily um we’ve got very active um and active neighbors who are really interested in architecture and design um in in the king so he he opened the bridge for us uh last year um that’s a kind of a segue back into Bridges I wonder if you want me to um this is one kind of close to where we live Central London um just north of King’s cross part of a a big development and in this case is this well you’ll see if we have time you’ll see this the the kind of first bridge in the development that we worked on but this was the second one where a client had asked us to do a relatively modest Bridge um that uh was still something that would draw people’s attention so in a way it’s it’s kind of I guess economy of action but um something that it allow it basically allowed us to to use a really simple form so a truss but um because we knew it needed to be expressive we we boiled it down to the specific details or the kind of really ref finding one module and then repeating it along um let us look at you know how every single part of that module is working as well as it could so expressing the compression members expressing the tension members angling the plates in the way that was working with the loads that they were dealing with so we end we ended up with this really efficient thing that was also quite sculptural and it stands out and it gives them what they want and it was just a lovely piece of design being able to get like from the get-go we knew we wanted to get really into the detail dets on the way it was built it was installed and then I think like the next level was how it contributes to the urban Realm of the area um so what you can see those green steps in the background are a place where people come to watch events in the summer on a big screen so you get people kind of congregating by the canal and then this bridge forms kind of like a side balcony where you can get more people watching the event or watching it’s great for people watching and it gets really busy and lovely there in the summer so this is this is the this is the last of our three kind of economies as it were so economy of material which is the most kind of obvious one in a way um and again I’m going to be a bit of a cheat and use not a bridge to talk about it because is all just design ultimately um this is a competition that we won well this isn’t but the next thing is competition that we won for a new type of OCS so the overhead cery system or the overhead power system for an electric Railway you’ll probably recognize this this is a French system but they all look the same the world over they’re kind of a you know meano up in the air hanging from wires with a ceramic Port insulators um and this is a competition to to rethink an OCS to to see if there’s a better way of doing it um so we sort of took the view that actually all that’s about is the position of the copper wire that carries the current to the train that’s the most important thing everything else all that paraphernalia up in the air is in service of achieving that that wire needs to be a very specific place for the train to get the current from it it needs to zigzag from one Mass to the next because it it didn’t zig a it’ be like cheese wire that would cut through the Train’s Pantagraph but beyond that it’s very simple it’s just geometry and you know if you approach it in the same way that we all approach bridge design it’s a geometric problem first and foremost you know how do you achieve this uh solution so you can see the sncf system from France and you can see our system which is 25% shorter gets rid of all of the Clutter um there’s again again to sort of reinforce the point as we switch through you can see how uh much simple our designers now we use the same sort of individual connection componentry of standard systems so much like the fountain at the start which can take any tap this can take any type of wire attachment whether it’s in the US or whether it’s Continental Europe or the UK um any registration arm um these are some of our patent drawings so we’ve got the the connection at the back of the mass is patented um and then you can see there’s one of our uh one of our prototypes we’ve got several prototypes one’s in our office in Scotland the others are in testing yards throughout the UK being tested on uh Railway um now the advantages of of it are a 25% reduction in height go cuz we don’t we don’t need the tension wires and what have you to keep this thing up in the air a 10% reduction in area again same sort of numbers when you’re looking in the elevation but this is the really main one 70% reduction in part count so all of those bits and pieces that are doing the thing on the left hand side are replaced essentially with one component on the right which is made out of a what’s called Pali which is a densified wood laminate it’s basically plywood but it’s plywood that’s been impregnated with resin at really high pressure so it’s got incredible electrical strength it’s a kind of Wonder material of the same generation as balite it goes back 150 years this stuff but everyone’s forgotten about it because its only use nowadays is in Transformer housings in fire stations where they get huge blocks of it Mill it out and stick the transformer in because it’s strong and it’s electrically strong but otherwise it’s not got any application except for here so we we’ve used this material to form the component in our Mass and it gives you these incredible figures because it’s essentially made of wood um you get a 75% nearly reduction in CO2 for just one Mast and then if you strap that to the whole Mast and then you run it across the whole length of hs2 you get this sort of incredible uh figure for um overall carbon reduction I’m going to skip the next but how do I do that skip oh yeah you need to skip it as well aw correct yeah so it it it looks like um I mean it weathers like wood in a way superficially so the surface goes gray and it will even like get lyen and stuff growing on it um but there are examples of this there’s actually a park bench somewhere in Switzerland made out of this and it’s been sitting there for 120 years and it’s like rock hard you know um so it’s really kind of it’s a w material um it’s it’s a bit expensive but it’s not but but it’s comparable um it’s comparable overall skip through these we were going I was going to talk about another building that we’ve approached in the similar way to the design of a bridge but we’ll skip through that here we go I’ll let Ezra talk about some bridges in Germany yeah I think that the relevance of this one is it’s a Timber bridge in Germany and um the way we approach it is really similar to the way we work on buildings usually and it’s all about kind of protecting protecting the M materials protecting the structural material so Timber is has a ton of potential in infrastructure design but only I think if it’s used in the proper way it’s not just used for the sake of using it so in this case we’re lucky to work with some jimber German Timber Bridge Specialists and they’ they’ve taught us a lot of things but clearly the first the first lesson is how do you protect the timber how do you use the form of the bridge to protect the timber so again it’s a half through structure beams on the outside U but the way we’ve done it is we’ve oriented them leaning slightly outwards with a metal cap over the top and kind almost building cladding on the inside um so you end up with this expressed blue lamb structure on the outside um clad over the top um the form of it is very much related to its span and structural performance it’s also um in a flood prone prone River so the structure had to be above deck we wanted to make sure people weren’t didn’t feel overwhelmed by these really deep beams so the the pathway kind of goes up and over and responds the shape of the beams responds to that as well keep track there and I think the other part of it is just understanding how these things are made what the opportunities are in terms of form and structure this is the second generation project we’re working with the same team in Germany and in this case it’s a Timber concrete composite structure so you’ve got the timber below shaped in the way needs to be shaped to handle loads but then the concrete above is actually what’s protecting it’s protecting the timber but then it’s serving the the double function of working as a compressive element top of structure this is back to me I guess this fit kind of quite personal um so we’ve separated economy of purpose economy of action economy of material there’s three different ways of looking at this but really um it’s a bit of a conceit because I think you could have taken any of those projects and swapped them all up and put them in any of the categories um because I think like I say economy is um an objective in its own right for all the work that that I think we all do actually um particularly particularly now with the focus on energy use and and carbon content so I’m going to close on a project where um I’m going to close my bit and then Ezra is going to talk about something else bit more current I’m going to close on the project where these aspects are almost imbalance at least uh as far as I can see um now this sorry sorry this isn’t the project um this is a this is nitos which is the very very first bridge that I was ever involved with as an architect so this is back in 1999 as was part of the competition winning team there were only three of us on the team this bridge in northern Greece um we worked at Wilkinson there architects I was working for at the time so it’s Jim a myself and then Angus low who was an engineer at um Arab in London um then there’s there’s me with with Angus slow on the left and Ian Wilson on the right Ian Wilson retired from AR uh last year Angus slow sadly passed away last year um and these two these two guys are basically my engineering Heroes um and we’re very lucky the people we work with are all kind of you know geniuses but but these guys have had such a profound impact on on my career um and the bridge we’re standing on is the last bridge that I’ll talk about which is Summertown Bridge which is just around the corner from Ezra’s Red Cross Bridge um and the three of us worked on this structure together um now the Genesis of it is actually a conversation that Angus and I had had like 10 years beforehand before this bridge is even a an idea and it was this discussion about how to do a bridge of EXT extreme Simplicity can you make a beam that’s just simply an expression of the bending moment that governs the shape it governs the form in the material so it’s using the least material it’s just the bending moment and then stiffening it um in order that it doesn’t Buckle so again doing the least you can do to achieve the structure but then doing it in such a way that you’re concentrating on the detail you’re making all these things come together in a really sort of beautifully considered way um and so this was the result so 10 years on we had a brief that came to us from related Argent same people who did Hudson yards here in New York um and this was our brief was to design this bridge and it was perfect opportunity for this approach because it’s in a historic setting so you got these Victorian buildings Victorian structures around it something of the Victorian attitude and what we were designing um you’ve got the canal the perfect span it’s 40 m which means can have a beam depth of 1.1 m in the middle it’s working quite hard this beam but so you get this beautiful form which is the parit it’s the structure it’s everything Allin one it’s using the least material this bridge is thinner than my thumb in its thickness but because of the way in which the stiffen is arranged and the top cords it’s a beautifully kind of stable and strong uh structure like I say just came from the bending moment skip through these I think there yeah so it’s probably um it Remains the favorite or one of my favorite bridges that the practice has worked on even though it’s very small compared to those other bigger structures is a Kind of Perfect expression in a way of this way of working and collaborating that we have that’s I think just going to talk about um just very briefly about three bridges that that we’ve got wo at the moment this is almost like the bonus segment so this is a competition actually it’s still jur is still deciding but this is a competition we’ve done in Oslo recently where client developer client has a basically building a whole new neighborhood or converting a neighborhood from Office Space into residential space and part of that they’ve identified there’s a river running down the middle of the neighborhood and they want to put in a couple well up to six or seven Bridges to really Stitch the neighborhood together um they brought in a a bunch of different Architects to all look at different Bridges at the same time um and we’re looking at three in close proximity um and it’s been a really wonderful exercise um designing one bridge is always fun but doing three at a time is is actually a new thing for us and it’s really cool because you get to understand or you get to think about relationships between the bridges um between bridges in the landscape and in this case we’ve um kind of use the same design philosophy but come up with three really different structures and each one is related to its function and its location so you’ve got one Bridge um one Bridge which is working really hard geometrically it’s connecting two banks that are at uh one is much higher than the other one so we needed extra length to get the ramps or to get the slope to work so it’s an s-shaped um structure to work geometrically it’s also for cyclist so it slows the cyclists down because it’s doing that um we’ve gone with a steel structure so a steel torsion box down the middle um and intuitively we thought um kind of getting over the water as quickly as possible was the right solution but the client actually pushed for this unusual situation where the bridge actually runs kind of parallel right down the middle of the river and then it it kind of spans the banks as quickly as possible and we we’ve been able to achieve that through the careful location of peers and crafting the form and then of course we we top it off with this nice handrail that runs along and expresses expresses the shape so that’s one of them um the second one one at the top the one at the top is a in this case it’s it’s again connecting high to low um really kind of a straight shot bringing users through the the river Valley at a high level so it’s almost Treetop walkway feel and in this one we wanted a really simple slim slender structure and bringing the abutments out to meet the structure keep the structures like short as possible uh in order to make it really slender we we pulled the tension member out of it and underslung a cable along the bottom so it’s similar to that German bridge but in this case even more kind of longer Slimmer more efficient and then third and final ones double to again totally desert you um the third one is right in the middle and it’s actually the lowest of the bridges so it’s in the the kind of flood zone needed to be really robust it kind of beds in well with the banks at either side it’s arounded a bend in the river so you’ve got asymmetry in the site one side it’s the inside of the curve where it’s it kind of gently comes down to the river and the other side is steep um so we’ve taken all of that on board and we’ve come up with a it’s like a segmental tension post tension Stone Bridge so breaking it up into slices of Stone Granite um stringing them all together tensioning them up um to serve as both the the structure but also the containment for vehicles so it’s really robust lots of opportunities for shaping that we’re excited about the shaping will of course have to do with the structural load going through it containing users something that’s tactile gives us a chance to play with structure and detail and all that stuff that’s Cedric price so we we’re wrapping up now and I think the moral of all of this stuff going back to that original quote you shouldn’t be interested in design of bridges is that actually all of us in this room are concerned with how to get to the other side and I mean that literally but also as a metaphor in terms of how we work together and and pursue the design of these things um thank you very much thank you very much that was excellent um you have any questions start with one go ahead if you do have a question and you’re at the table please pop the microphone so it this is probably a a bit of a a local question for based on the experience of London but um the victoria dot Bridge yeah in the plan you showed it was right next to the existing Victoria dock Bridge yep all spotted um yeah well I used to cyclopaths there all the time that’s quite the existing Victoria dock bridge for anybody who doesn’t know it’s a it’s a stay cable Bridge it’s of quite an unusual design but it’s quite high level because they built it on top of elevator shafts basically to give the clearance for like super yachts and stuff to that use a dock to you know get up and down um was there any it it just seems a little bit uh incongruous in terms of like you know the carbon emergency that you’ve got an existing Bridge here already yeah and then you’re building a brand new bridge right next to it absolutely was there any consideration given to reusing that structure or yes improving access yes sadly um it was that structure I mean Li Davidson who are The Architects I forgot the engineers Bureau app I can’t remember um I can’t remember who the engineers were but um they’re not in the room so I can say this that bridge is absolutely not fit for purpose in its current the current requirements of the bridge I mean it was fine when it was built CU you know it only had you know tens of people crossing it a day but the development that silver town is I we mentioned it’s going to have thousands of homes in what’s currently a derel part of London uh and then there’s a new station to the north as well so the bridge needs to cater for tens of thousands of people a day rather than tens of people a day and the so the LIF ships Bridge has the elevators which keep breaking down um and you got stairways and all the rest of it so if the elevator is not working then people who aren’t um you say Able Body can’t use the bridge um you know this there are so many problems with that structure the the deck is very narrow so even if you could guarantee getting people up to it you wouldn’t have the capacity so the AR bridge in fact um started off at 5 meters wide for capacity but we did additional capacity modeling with Arab um that suggests they need to be six six yeah six meters wide so um we’re talking of an entirely different brief um but I agree you on the face of it two Bridges next to each other they’ll seem a little bit odd but and I think we we’ve talked about moving that bridge or reusing it somewhere that makes more sense but I think there’s so much underground for that structure it’s not a simple pick up and move bridge but actually the one nice thing is at the ends of our Bridge there’s going to be signs saying it’s about to open and if you’re in a hurry go use the high high level bridge to bypass it because it it takes about 10 minutes open and close so it it will serve kind of an overflow function at times but yeah okay yeah a Prett good question though um typically in the in the UK is the architect commissioned first the engineer or is it typically a a team or is there a forced marri at some point has typically so in the best instances it’s a team because it being a team actually reflects the way in which the process occurs when it occurs well um the king’s cross Bridges so the red one and my favorite one um the architect was appointed and then AR were appointed secondary to us but that’s unusual I think normally we will be a subc consultant to an engineer very happy to be self consult to an engineer um but best instances are when when you go in as a combined team and whenn the commission anyone else I have one more um regarding the uh the pre-cast segmental Bridge there were a couple of them I think at least one um was there am I correct that there was a moratorium of sorts on that type of yes Bridge so so T Val so the the one that I describe as Lego um yeah exactly right so in the UK for quite a long time there’s been a moratorium on that type of connection which is why the technology has advanced in for instance Spain so well in recent years on their high speed rail products but nothing has happened in the north of Europe and it’s basically through with um uh deicing salts on the road um and because it’s a railway it’s a long way from a road there aren’t going to any deicing salts so that has enabled that scheme to be progressed um but that’s the reason you’re quite right there is an moratorium or has been there yeah I think there was a there was a a detail with the the cables and there was some bad detail that was addressed yeah so it’s accept you’re exactly right yeah teolog yeah exactly and and and understanding you know changing shifting requirements as well yeah Could you um just talk a little bit about the um the process of conceiving the the the concept and then having the dialogue or the relationship with the engineer yeah and how critical that is to have super critical so um I mean that’s kind of goes to the absolute heart of it and I just sort of mention in passing that I don’t really like talking about disciplines particularly Architects Engineers or but I mean yeah we have our own responsibilities and um you know there there are liabilities and you know kind of areas of expertise absolutely but ultimately we’re all in this world we’re all kind of bridge designers so we’re all looking to achieve the same end ultimately which is really good Bridge um it’s perfect for its location and its use and Etc and um I’ve had conversations with Structural Engineers notably guy called Paul Sanders who’s a partner at Kobe in London um where Paul has suggested ways of looking at a structure from an architectural or an aesthetic point of view and in the same conversation I’ve had suggestions to him as to how this stru just going to stand up I can go into detail about it we we talk about it whenever we meet um it was like a complete role reversal but we was totally unself conscious it happened because we’re just working around a table and that’s the best situation to get in I mean if you rewind in history separate disciplines for Architects civil engineers stru didn’t exist you know there were I mean I don’t know what they call themselves they probably call themselves Architects sign but it was all combined Thomas Telford the great Scottish engineer who built you know hundreds of bridges in his lifetime started off as a stone Mason then became an architect then civil engineer but civil engineer only just became invented pretty much by him and his career um and then he went back to Bridges con structur all the rest of it but there was no difference for him it was just part of the same kind of continue with design and and what have you and so the best bridges are where you can’t tell whether an architect been involved or not really but it’s just invisible are there any questions online we have about 20 20 or so people if you have any questions please speak up two one is your project with stones post tensioning system with ston it’s very interesting it’s new technology I think never seen before are you in touch with any designers doing that or just uh are you getting any support from some specialist there well we we are again working with K on that on that one but um and they have a couple people who are looking in this Stone I I think there are some examples of it being already there’s a like a carbon footprint it’s brilliant yeah it’s amazing it’s a beautiful idea I like it I think it’s also in a location that has good Stone so the qu we’re not bringing in Stone from China so one point for you on that but on the other one I want to know you got on the bridges cotton yeah with the very nice idea don’t know jimo does think about that bridge I was expecting to you to comment on that bridge the LIF the yeah have you go any uh carbon Management in place there because I think with four tons right why do you want have four of them more maintenance more material the idea of having one that turns it’s very e this is also a brilliant question because you get to the heart of it so you got a good thing with stones but I’m really curious to know why you like you’re really putting us on the spot no I mean no just interesting and very interesting but well the SP this The Spar one is really interesting because we actually questioned it ourselves and we wondered and I mean this is stuff you guys want doing all the time but with if you look in the future to the cost of electricity and the cost of energy and you compare that to the investment in material up front was actually really close like if with no counterweight you just push on you just push harder over time it was actually going to break almost even but then you brought in the client and their need for something interesting and I think that kind of just tipped the balance towards doing a counterweighted structure no pun ATT um and yes you know there are more moving Parts but they’re off well relatively off the-shelf moving parts so they will require maintenance and the replacement but we thought overall it actually was more efficient if you’re going to do it try to do it as efficiently as you can and make the most use of that mass to to do the lifting as we want to okay well thank you very much thank you than you thank you confidence in you um e e e e e e e e e e e e e e e e e e e e e e e e e e e e