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Entries in concrete (26)

Friday
Apr142017

material permanence for an impermanent architecture

Rau. Triodos Bank, Driebergen-Zeist, 2011-Thomas Rau was recently speaking at Ryerson; the notification was illustrated with his 2011 Triodos III project, a values-based bank in Driebergen-Zeist, which encapsulates his thesis that Nature is a bank and if we treated it as such we wouldn't exploit it as we do. By extension, every building should be considered as a bank of materials, valuable because finite, like currency, which circulates over and over again through time and society.  Triodos III is an example of such an architecture.  A logical extension of the idea of a building as a bank of materials would be an architecture that is demountable, with individual pieces salvageable as whole units rather than the pulverising demolitions that usually happen when a building reaches the end of its usefulness (not necessarily its life, but the limits of appreciation of its value).  In this it is assumed that buildings have a life span.  

from: Shaun Fynn. Chandigarh Revealed: Le Corbusier's City Today. Princeton Architectural Press, 2017Was this a consideration when Le Corbusier was building Chandigarh, seen in a new book, Chandigarh Revealed: Le Corbusier's City Today, by Shaun Fynn?  His was a hugely complex architecture built with a single material, concrete, that once cast cannot revert back to its original ingredients – the chemical reaction when water meets quicklime cannot be undone.  Correctly built, this kind of architecture was forecast to have an infinitely long lifespan; deconstruction and reuse of the materials was not considered.  

Unlike concrete buildings regularly demolished in the western world, despite the new-found mid-century love of béton brut — so much of it already gone, Le Corbusier's Chandigarh project persists: there has been little development pressure to constantly rebuild in what was the de-colonising, developing, third world.  Modernism was the architecture of liberation: it promised a new start, in all senses, and for this it retains a political and historic power that we don't recognise here.  New Generation Thinker Preti Taneja, Leverhulme Early Career Research Fellow at Warwick University, read an essay recently in the New Generation Thinkers series, about 'The first generation of post-Independence architects [who] built on this [modernist] legacy, drawing also from Le Corbusier, who designed India's first post-partition planned city, Chandigarh, with its famous 'open hand' sculpture; and from Frank Lloyd Wright and Walter Gropius, to create some of the most iconic public buildings across India today.' 

There is something about the utopian socialist roots of modern architecture that meant something in the developing world but which passed the developed world by. Here, it is seen as a style, not as something for social good. Indeed, by the 1970s, projects just twenty years old, such as Yamasaki's Pruitt-Igoe in St. Louis, were totally discredited as the social ambitions of the architecture did not match at all the political fears of race and poverty.  

Rau: TurnToo, a declaration of material rightsRau's architecture as material bank refers to a pre-industrial model of building, where buildings were assembled and dis-assembled by hand.  He extends it to industrial processes, with the circularity potential of each material as the pre-condition for its use.  It has the potential to redevelop modernism without the extravagance of material exploitation that came so easily to us in the west, where the environment was assumed to be infinitely patient with us, self-healing the wounds we inflicted by fire, by mining, by impermeable cities, by voracious appetites.  His architecture of circularity assumes an impermanence to buildings whereby they can be constantly in flux, parts replaced, parts repurposed.  This is such the polar opposite to the still, eternal, immoveable architecture of Chandigarh.

from: Shaun Fynn. Chandigarh Revealed: Le Corbusier's City Today. Princeton Architectural Press, 2017

Thursday
Jun122014

Maracaña: O jogo bonito

Maracaña, 1950. Reinforced concrete stadium built for the 1950 World Cup, Rio de Janeiro.

In his 2004 book, Stades du Monde: sport & architecture, Angelo Spampinato listed the Maracaña stadium in Rio de Janeiro as one of the legendary temples of football. Built between 1948 and 1950 for the 1950 World Cup, it was deliberately designed to be the largest stadium in the world, seating 183,000 with standing room for 220,000.  The World Cup that year opened with Brazil-Mexico (4-0) and ended calamitously with Uruguay-Brazil (2-1).  

For 2014 the bottom tier was rebuilt, a new roof added and seating has been reduced to 79,000 with the loss of the Geral, the standing terraces. This took $735 million of Brazilian public money and then the running of the Maracaña was effectively privatised, turned over to AEG, owners of LA Galaxy and the O2 arena in London, on a 35-year contract.  A bit of controversy there.  An adjacent indigenous museum and a school were demolished.

The Maracaña is heroic in volume and history: Pele's first and thousandth career goals, thousands of match upsets, despair, elation, rock concerts, two masses by Pope John Paul.  Its original engineer was Paulo Phiheiro Guedes, working with a team of architects.  Evidently, as stadia go, it is very flat, just five storeys from pitch to the top of the top ring.  Most of the renovations are hidden: new media centre, locker rooms, auditorium, boxes. There are 1000 new parking spaces under the stadium, another 13,000 spread about the neighbourhood. Visible are new seats and the extended roof which now covers all the seats and is fitted with photovoltaic panels.  

Estadio Maracaña, opening after three years of renovations, April 2013Estadio Maracaña is one of twelve FIFA World Cup stadia, but of course its expansion is also part of the preparation for the 2016 Olympics. The World Cup is the preliminary scrubbing of Rio, which will continue for the next two years.  China was able to remove great chunks of old housing and historic infrastructure as it gives itself licence to do so.  Brazil is doing the same, without the licence.  The people are becoming obstructive, there will be delays. 

Tuesday
Oct292013

grafitti 2

grafitti, Southbank Centre, London

I published a photo of one of these mushroom columns during my concrete discussion last year, which covered issues of formwork, brutalism and transparent construction methods.  The historic value of brutalism, erupting in England over the demolition of Peter and Alison Smithson's Robin Hood Gardens, has reached this brutalism backwater, where the only truly béton brut building we have in this small city, the Planetarium, is never discussed, but dreary copies of copies of le Corbusier are.  It is as if theoretical debates are heard as murmurings from distant stars – misheard actually and applied to completely inappropriate pre-cast concrete-panelled buildings.  

The photo above, of a kind of grafitti paradise, says nothing about the architecture, its function or ownership (so this isn't political protest) but does say something about the identification of concrete surfaces as durable canvas and about gaps in surveillance.  Elaborate wall paintings take time; time is allowed here.  It isn't the grafittiists that disrespect the buildings, but the owners of the buildings themselves who are responsible for their care. 

Friday
Mar222013

Denys Lasdun: modernism deeply dyed

Denys Lasdun. Royal College of Physicians, London, 1960

Lasdun felt his best building was the 1960 Royal College of Physicians, set into the Georgian terraces of Regent's Park, London.  We don't get this kind of outside space anymore, noir-ish, uncompromising, heroic: terraces for the dark life of the soul.  Instead, having looked at an archive of drawings over the last year of contemporary civic public space proposals, according to the renderings, we must all gaily trip through our cities in full colour, casual clothes, balloons flying, children laughing.  

The public spaces of modernism were adult spaces. They weren't spaces of power but of public access, and that was, given the history of European property ownership and display, a serious business.  History wasn't interesting – it had caused two ghastly wars and in the 1960s the tall capacious houses of Regent's Park were likely to either be offices or carved up into a dozen cheap bedsits.  The bones of the elegant curved terrace could be honoured, but not much else.  

Denys Lasdun's son, James, seen below in an excerpt from a talk at the New York Writers Institute in 2009, speaks about the fierceness of the modernist tenets he grew up with.  Ironically, especially when he says that postmodernism was anathema to Denys Lasdun, James has recently published a book, Give Me Everything You Have, on the ultimate postmodern crime: he has been cyber-stalked since 2006 by a student he once taught at NYU.

Monday
Jan072013

Eladio Dieste's bricks

Eladio Dieste. Salto bus station, Uruguay, 1974

Dieste's hallmark: double cantilever self-supporting thin-shell single-layer brick vaults.  Here for a bus terminal in Salto, Uruguay in 1974.  Dieste lived from 1917 to 2000, a surprisingly contemporary career, little known here.  Gaussian vaults: double curves.  The book on all of this is Remo Pedreschi's The Engineer's Contribution to Contemporary Architecture.  Pedreschi's explanation of masonry vaults points out that the thinness of the shell is dependent on the dimensions of the block and the finishing layer, typical ratio is 30/80. Dieste's vaults were 130mm thick, and the vaults spanned 50m, an astounding relationship using bricks and mortar and not achievable using concrete.

Pedreschi writes that 'Dieste's sense of cosmic economy' – what a lovely phrase – led him to derive strength from form, rather than from mass, using hollow brick (2/3 the weight of concrete) and extremely shapely catenary curves, i.e. higher, curvier vaults.

So, what was going on in Uruguay while this beautiful work was being built? State of emergency in 1968, Tupamaros geurillas defeated by the military in 1973, torture, break up of the unions, torture, the removal of the Communist Party, torture, political prisoners, dictatorship, mass emigration, economic crisis, desaparecidos. 

Does stability lead to complacency, and does complacency lead to dull thinking?  I've always thought so myself.  In theory it should be the opposite, but in practice it isn't.

Wednesday
Jan022013

Центросоюз: Tsentrosoyuz Headquarters, 1936

ⓒ Richard Pare. Chromogenic colour print: Centrosoyuz headquarters, Moscow, 1999.

Tsentrosoyuz [Центросоюз] headquarters [Central Union of Consumer Cooperatives], Moscow, 1929-1936. Le Corbusier, Pierre Jeanneret and Nikolai Kolli.
The astounding architecture of Soviet bureaucracy: offices for 3500, restaurant, lecture halls and theatre.  

The construction is reinforced concrete with 40mm thick blocks of red tuff used as insulation. Tuff is volcanic ash – small pieces of magma < 2mm – blown into the air during a volcanic explosion and consolidated into a porous aerated easily carved material.   The tuff used in the Tsentrosoyuz headquarters is from the Nagorno-Karabakh region, an area rich in limestones, tuff sandstones and clay shales.  This is all starting to sound familiar.

Friday
Dec142012

engineered cementitious composites

ECC incorporates super fine (100 microns in diameter) silica sand and tiny polyvinyl alcohol-fibres covered with a very thin (nanometer thick), slick coating. ECC has a strain capacity of 3%, regular concrete has a strain capacity of 0.1%.

ECC: a ductile concrete that does not use coarse aggregate and does include a coated network of fine polymer fibres within the cement that allow it to slide under stress, so no irreparable breaches, just thousands of fine cracks, dusted with cement, that self-repair with water.  

Engineered cement composites were developed at the University of Michigan by Victor Li in the early 1990s.  Although fibre reinforcement comes in many modes; the ECC uses micro-scale (10 micron) fibres that actually bond the cement within the concrete. They introduce a plasticity that allows the concrete to deform rather than break. In a paper by Victor Li, the abstract states: Engineered Cementitious Composites (ECC) is a material micromechanically designed with high ductility and toughness indicated by multiple micro-cracking behavior under uniaxial tension.

Neat.  Apparently ECC is of great use in bridge repairs where there is an incompatibility between old concrete under stress and new normal concrete patched in, which is both shrinking and calcifying at a different rate, introducing weakness at the old/new interface.  ECC's flexibility – its internal slipperiness – does not allow it to shrink and crack.  And in  2003 in Japan where most of the applications seem to be, it was sprayed in a 20mm layer over 600m2 of the aging, cracking, leaking and spalling Mitaka Dam.

To add to all of this wonderfulness is that its life cycle costs are lower than conventional concrete (tested on bridge deck systems: agency costs – material, construction, and end-of-life costs, plus social costs – emissions damage costs from agency activities, and vehicle congestion, user delay, vehicle crash and vehicle operating costs. These costs were estimated across all life-cycle stages (material production, construction, use, and end of life) over a 60-year analysis period.)

At 40 times lighter than conventional concrete, and with its bendiness, clearly it is headed towards earthquake zones, which perhaps is why it is well-deployed in Japan.  Life cycle costs can be misleading: although over a 60 year period it might be less expensive than ordinary concrete construction, I'll bet those little polyvinyl alcohol fibres with their slidey nano-coating cost a bundle, and are inaccessible to most of the people so devasted, and so regularly, by earthquakes.

Thursday
Dec132012

oyster shell middens

John Heron, Hidden Midden 1. 2011

We are talking about numbers of oysters at an almost inconceivable scale: there is an Oyster Shell Beach in Hong Kong, Oyster Bays in both New York and New South Wales, Oyster Creek in New Jersey, Oyster Point in San Francisco, Oyster Cove on Vancouver Island, Oyster Bed in Prince Edward Island.  There is an Oyster, Virginia.

Oyster middens can be miles wide: two kinds, the discards of oyster-eating peoples, and natural banks of oyster shells on beaches.  According to Kaitlin Pomerantz, the erosion of empty shells releases calcium into the water needed to build new oyster shells, plus providing a foothold and a habitat for new oysters.   

However, tons of oyster shells were used as road beds in the early twentieth century; more tons were ground up for chicken feed and agricultural use.  It is a similar story to the mountains of buffalo bones photographed beside the CPR line in Saskatchewan in the 1890s: destination, fertiliser.   Oysters are under threat from over harvesting and the removal of habitat. So, nothing new then.  

Pomerantz has built a monument, Hidden Midden, for Chesapeake Bay (between Maryland and Virginia), not quite as tidy as the drawing above, but better: it is topped by a slab of asphalt road that registers the destruction of oyster middens, and offers a footfall for occupation, not for oysters unfortunately given that it is in a sculpture garden, but for other kinds of life.

Kaitlin Pomerantz, Hidden Midden, Annmarie Sculpture Garden, Solomons, Maryland. November 2011.

Tuesday
Dec112012

tabby

From the elegantly sublime, Niemeyer, to the desperately expeditious:

Tabby concrete. St. Augustine, Florida. Photo by Nathan Wolkenhauer, 2011In between Roman concrete and the discovery of Portland cement in 1830, there was tabby: burnt oyster shells (lime), mixed with water, sand and broken shell.  Originally Moroccan, although North Africa was part of the Roman empire so it might be continuous with Roman concrete work, the use of tabby migrated to Spain and eventually to Spanish colonies, such as Florida, using broken shell as aggregate when stone was not available.  

The lime/sand/water combination occurs all along the lower east coast of the USA, dating generally from the early 1700s.  The oyster shells were found in huge middens left by the aboriginal peoples of the Atlantic coast. The reported size of the oyster shell piles, and the size of the shells themselves – 6 to 8" x 15 to 20", evidently oysters were gigantic in pre-historic times – indicates a cultural landscape rarely discussed and long vanished.There are shell middens on all coastlines, often thousands of years old, but not all were turned into sources of lime for concrete.   

An article by Jingle Davis on the Tabby Trail on the southeast coast of the US tells how the shells were found, mined, fired, and the resultant lime and wood ash mixed with clean sand and water.  Floors were laid and hammered with linseed oil into marble-like hardness. Walls were built up using slip forms.  

Now, here's a recipe: ten bushels of lime, ten bushels of sand, ten bushels of shells and ten bushels of water gives you sixteen cubic feet of wall. 
1 bushel = 8 gallons, so presumably a bushel of lime is enough lime to fill an eight gallon container.  There is something suspiciously coincidental that all the components for tabby are in ten bushel portions.  It might be loose science, done more by feel than precise measure.

It is interesting that the making of tabby almost replicates the process of producing calcareous limestone itself.  There is something about all this lime, heat and water process that is strangely circular.

A tabby building at the Kingsley Plantation on Fort George Island in Jacksonville, Florida. Tabby concrete was used in the 1700s and early 1800s in Florida and coastal Georgia. In this photograph, one can see the slip-form casting method uses, whereby each course is a seperate pour. When set the board formwork is moved up for the next pour. photo credit: State Archives of Florida, Florida Memory

Thursday
Dec062012

oscar niemeyer

Oscar Niemeyer, Museu Nacional da República, Brasilia, 1958

Wednesday
Dec052012

concrete occupation

FIRST FARMERS FOR 2500 YEARS TO SETTLE GILBOA IN ISRAEL ; 4 DECEMBER 1962 ©TopFoto

This is from TopFoto's '50 years ago' from December 4, 1962. The note that accompanies the image reads: "David's Curse Lifted"  Mizpeh Gilboa, Israel.  Two of the new settlers at Mizpeh Gilboa are pictured mixing cement and sand for their new houses.  So far six permanent buildings have been erected in the settlement plan according to the settler's choice.  Water is still brought up by tankers from Nurit, but a pipeline [from] Beisan Wells is planned.  UPI Photo 1962

The headline indicates something of the myth of terra nullius that was prevalent at the time of the 1967 War: that no one lived in this new land, and if they did, they weren't taking advantage of it.  

It also shows how concrete allows relatively unskilled fabrication: two farmers, sand, rock and tankered-in water. And yet the results are so permanent that they take on the inevitability of geology.  It is that re-mineralisation that cement goes through that so distorts the legitimacy of construction.

Tuesday
Dec042012

on being brutal

Long & MacMillan Architects. Calgary Centennial Planetarium, 1966. Here, shown in 2009, during the construction of a new LRT line that sliced through the site. Stephen Barnecut photograph.

This past few weeks investigation into concrete started when I was asked why Calgary is over-represented by brutalist architecture.  This came as a surprise, as it hadn't occurred to me that it was, and I wondered why this very particular term was all of a sudden in common parlance.  As Adrian Forty mentioned, concrete can arouse great antipathy, and brutalism seems a fitting epithet.  

We do have a lot of semi-civic buildings done in the early 1960s for education boards, the library, the YMCA, a police station, a remand centre (torn down last year) which sit like dark suspicious toads at the east side of downtown.  Late 1950s / early 60s Calgary commercial towers, lovely office buildings of enamelled spandrel panels and opening clear glass windows, had none of the brooding qualities of the institutional architecture built at the same time. 

What were they brooding over?  Probably the threat of civil unrest that so dominated the United States at the time.  The concrete Calgary Board of Education Building is a version of the concrete Boston City Hall, which itself was a version of Le Corbusier's concrete La Tourette, a monastery for retreat and isolation, not qualities useful for either a city hall or an education administration building.  The line of influence from Paul Rudolph et al to Calgary came with the first oil boom.

Did we have civil unrest?  no.  Were we under threat from the USSR?  only geographically, as at the time everyone thought a US/USSR war would be fought over northern Canada.  Was the oil industry worried?  clearly not.  It built vulnerable, glassy, curtain wall towers, and still does.  

Our best building from the era was Long & MacMillan's Centennial Planetarium: a great eruption of roughly-poured concrete that looked as if the geologic substrata had cracked open the grassy prairie. It was topped with a moon-like dome that did all the stars and space stuff.  When space was no longer magical, it became the Telus Science Centre, which has since moved elsewhere.  The building might now become a city art gallery.  Somehow its architecture has become completely marooned, both formally, physically and conceptually.

Friday
Nov302012

Adrian Forty: the metaphysics of concrete (21 Feb 2012) 

For when you have 40 minutes, here is one of University College London's lunchtime lectures:

from the YouTube posting:

'Uploaded by on 27 Feb 2012

Professor Adrian Forty (UCL Bartlett School of Architecture)

Almost three tons of concrete are produced every year for each man, woman and child on the planet. It is now second only to water in terms of human consumption. Yet how has the astonishing take-up of this new medium within little over a century been accommodated into our mental universe? While it has transformed the lives of many people, in Western countries it has been widely vilified, blamed for making everywhere look the same, and for erasing nature. Architects and engineers, although they have primary responsibility for 'interpreting' concrete, are not the only people to employ the medium, and many other occupations - politicians, artists, writers, filmmakers, churchmen - have made use of concrete for purposes of their own. The results are often contentious, and draw attention to the contradictions present in how we think about our physical surroundings.'

 

Thursday
Nov292012

concrete bombs

Soviet WWII 25kg concrete Avia bomb

I'm not sure that this isn't some elaborate hoax, but there seems to be enough history from different eras that it must be true. 

Concrete bombs were made between November 1941 and August 1942 in Novorossiisk, USSR, until the German Army approached and the concrete plants were moved away from the front to Georgia.  Concrete casings were made for bombs up to five tons, stuffed with either explosives or chemicals.
Slate mines, also Soviet WWII weapons, cast asbestos concrete into slabs (or slates) which then were assembled into boxes and stuffed with explosives.  Only the fuses were metal, so escaped mine-detectors. Slate mines were very inexpensive, but quite fragile.

Solid low-collateral damage small-dimension concrete bombs were used by the US Army in the late 1990s and again in the Iraq War, laser-guided for direct hits on specific targets. In theory, there is less collateral damage in civilian areas because there isn't the wide spread of shrapnel.  Some concrete bombs are loaded with explosives; many are concrete alone, relying on speed and weight to knock out a narrow target.

A 300kg concrete bomb was dropped by a French Mirage on a Libyan tank in 2010.



Iran's ultra-high performance concrete, UHPC, is made of sand, cement, powdered quartz and, variously, polypropylene fibres, long steel fibres, plus various metal-oxide nanoparticles. The stronger the concrete bunkers, and UHPC is seven times stronger, the larger and more penetrating must the missiles be.  The larger the missiles and bombs, the larger and more reinforced the bombers must be.  Right now, according to this 2012 piece in the Economist, 'Smart concrete', there are 'bombs which can tunnel through hundred of metres of rock and concrete'.  

On one hand we have great chunks of concrete dropping from the sky onto tanks, on the other we have nanotechnology escalating bombing and bunkering to a scale unimaginable to civilians.  The US Air Force has acquired the Guided Bomb Unit-57A/B Massive Ordnance Penetrator which weighs 15 tons and can penetrate 200' of hardened concrete.  There is more semi-technical stuff here.

Someone on one of the military forums, which one is inevitably drawn into when tracking down anything at all to do with war things, commented, 'it is the 1st century meets the 21st', by which I think he meant laser-GPS-guided boulders.

Wednesday
Nov282012

aggregate

Metalled road, Reinga, New Zealand.

Aggregate, in general, is mined, either as gravel or as stone which is then crushed to roughly 10mm sized pieces for concrete.  Historically this rock was called metal, from the Greek, metallon, or quarry/ore/metal, from which comes the term, a metalled road, something one finds in John Buchan novels where the hero and his invariably boyish girl companion hurtle across Scotland in their roadster on narrow tracks and if lucky, a metalled road.  Which merely means a gravel road.  The term is still used in New Zealand evidently.

Metalling is a process developed by John McAdam in 1820 where layers of ever-smaller sized aggregate are laid down on the road bed and with wear the sharp edges will pack together making a dense and weatherproof surface.  It is made even finer if the surface is coated with a mixture of stone dust and water, filling up any gaps between the stones.  Coating the lot with tar (tarmac) reduces dust as the surface stones break down with excessive wear.  

Asphalt is a name for bitumen, something we know a lot about here: originally called the tar sands of northern Alberta, the scientifically neutral term is the bitumen sands, the industry term is the oil sands: it is all heavy semi-solid petroleum.  Whatever, an asphalt concrete road which is what most of our roads are, is a gravel road topped with a layer of aggregate mixed with bitumen as the binder, rather than cement.

None of this is exotic, the basic materials seem to be everywhere, and evidently aggregate mining is what most of mining consists of.  There is a nasty history to rock breaking however, considered hard labour and done by prisoners well into the 20th century – including Nelson Mandela on Robben Island, and it is still done by women and children in the more benighted parts of the world.

 

Tuesday
Nov272012

glass cullet

Glass cullet is what all your recycled bottles become: pieces of glass smaller than 19mm but larger than .075 mm, $300-500/ton depending on colour, composition (borosylicate lab glass for example) and destination – glass production, landscape material or aggregate.

Concretes made with green glass cullet aggregate have been found to be stronger, attributed to better bonding with the cement – this reported in the Magazine of Concrete Research in 2004.  And while it seems that glass cullet concrete is used for lots of rough applications such as roadbeds and fill, as an aggregate in concrete it increases the strength and insulation value, glass having better thermal qualities that other aggregates.  

So, what does it look like?  This is a decorative application, if used as normal aggregate it would be invisible.

 pretty, but is it only used for counter tops? Ah. yes. washed gravel aggregate is $4/ton.

However, milled glass has been used as a partial replacement for cement, where the glass undergoes 'pozzolanic reactions with cement hydrates, forming secondary calcium silicate hydrate', producing 'significant gains in strength and durability of recycled aggregate concrete'. [This from a really interesting paper by Roz-Ud-Din Nassar and Parviz Soroushian here]   Milled glass in the cement allows a greater range of waste material to be used as aggregate.  

It is very interesting that such an ancient building material, formed through a series of chemical reactions, is so complex, certainly not to be taken for granted that we know all there is to know about it after many centuries of use.

Glass in all its lovely varieties – Gabbert Cullet in Williamstown West Virginia:


Gabbert Cullet, Williamstown, West Virginia. The backlot

Monday
Nov262012

t-walls

New World Design LLC, the Future Project – T-Wall Housing Proposal, Al Querna, Iraq

T-walls are the concrete units devised for the West Bank barrier wall in Israel.  Different versions are used throughout Iraq and Afghanistan by the US Army: the 1.1m Texas, the 3.7m Bremer, the 6m Alaska.  The 1m traffic barrier, Jersey, has sloped edges at the base and is used on highways seemingly everywhere.

New World Design, Jeffrey Olinger, Heather Boesch, Darby Foreman and Cliona McKenna, have developed a housing project based on T-walls for Al Querna, Iraq.  The T-wall unit is at once concrete wall and foundation: the units are deployed in a morse code grid, and houses are developed from and between them.  A basic L-shaped house unit multiplies to make alleys and courtyards in a number of configurations.  

The project is simple and subversive.  It is useful and uses the defences of war.  It is culturally cognisant and based on imperialist debris.  How much more interesting can this be?

Despite that the term, T-Wall, is a registered trademark of the Neel Company in Virginia for precast retaining walls, t-wall is the common name for the barrier units.  The Arab Land Group, established in 2003 and headquartered in the UAE to work with the US Army, manufactures the barriers.  

Clearly the shape of a pre-cast reinforced concrete slab with a footing cannot be proprietal, any more than can be a gable roof.  What New World Design has done is to appropriate a form that divides and obstructs, and to de-nature its malevolence as a form by embedding it in the construction of housing.

Friday
Nov232012

concrete cities

Palestinians sort through the rubble of a house hit by an Israeli air strike in Gaza City, Nov. 18, 2012. Alessio Romezi, photographer, for Time

In the recent coverage of the civil war in Syria and just this past few weeks, the bombings in Gaza City, one is struck by the sheer amount of concrete and rebar left in great tumbled piles.  No trees, no wood, no parks or lawns, Palestinian refugee camps and Gaza itself are dense concrete worlds.  

North Africa and the Middle East sit on a shield of limestone, interleaved with layers of sandstone.  It is all made clear in a really interesting paper on the significance of reef limestones. Calcareous limestone: fossils and shells, sand from the edges of the ocean, oil from the animals and vegetation that lived there: it is geology itself that produces the wealth, the tensions and the landscapes of the Middle East, and has for a long time: the pyramids are sandstone blocks, faced with limestone sheets.  Photographs of Palestine in the 1920s show a sandstone architecture, however, quarrying and building in stone is not the process for quick reconstruction in war, concrete clearly is.  

Concrete debris can be re-used as aggregate: it isn't as strong, but there is lots of it.  All the steel reinforcing bars and mesh can be hammered out and re-used, and concrete can always be mixed in small batches, by hand if necessary.  Not that the entire Gaza Strip is in rubble; there are concrete companies with perky websites just as there are anywhere else.

The Israeli blockade of Gaza allows the entry of construction materials from Egypt only for Palestinian Authority projects.  As the PA does not operate in Gaza, Hamas does, the list is effectively embargoed.  Nonetheless, the territory sits on limestone, abuts an ocean full of sand, and is provided with rubble of all kinds on a regular basis.

Thursday
Nov222012

mega-quarry woes

Melancthon is 120 kms north west of Toronto. This area is classified as Class 1 agricultural land, boasting a rare and unique soil called Honeywood Silt Loam which grows a multitude of vegetables, especially potatoes, and serves as a source of local food production for the Greater Toronto Area

Melancthon Township, Ontario, potato farms.  2011 a US-backed company applied to the provincial government for a limestone quarry.  2400 acres, a billion tons of Amabel dolostone 58 metres deep.  Big protests: farmers, First Nations, ranchers, environmentalists.  Big problems with water, as 58 metres is well below the water table, water, 600 million litres a day would rush into the excavation and have to be taken away.  To where and how?

Yesterday, project abandoned.  The Globe reports that 6 years ago a purported potato farmer started to acquire land, and last year the mega-quarry was announced.  The spokesperson for Highland Companies which owns the land and will continue to farm it, said the problem is that they didn't engage the local community or explain well enough the benefits of the mega-quarry. 

This is how CAPP always puts it and why they run a massive campaign on how wonderful oil sands development is on Canadian television channels: if the public objects to any kind of resource-extraction development such as the oil sands, or in this case, a mega-quarry, it is because the public doesn't have the right information.  Then throw in how many jobs have now been lost with both the quarry and related industries and well, the public is a fool.

The Suzuki Foundation didn't think it such a good idea; they aren't exactly ignorant, and the local website the map above comes from lays out some very convincing information. And it might be that the public does have the 'right information' but doesn't like it, or believe it. Must the equation be money/jobs vs environment, even if that environment isn't wilderness but is already engaged in some other industrial capacity, such as agriculture?  

It shows what a player limestone is: roads, building, development – a mega-industry with mega-installations. 

Wednesday
Nov212012

lime kilns

Near Victoria, BC: the lime kiln of the Atkins Brothers Silica Lime Brick Company, near the boundary of View Royal and Langford. Enough lime was being produced to justify a spur line from the E.&N. Railway, shipping a thousand barrels up island in 1899. Lime operations continued until the 1930s when the land was purchased by the Department of National Defence. Robert Duffus: 1977 photograph

There is a Lime Kiln Lake near Pincher Creek in southern Alberta, the Lime Kiln Trail in Ottawa, the Hart Road Lime Kiln Conservation Plan in View Royal near Victoria BC, Lime Kiln Bay in New Brunswick – when you start to look, they were everywhere.  

Funny how things channel sometimes.  Last night was reading Agatha Christie's The Disappearance of Mr Davenheim, written sometime before 1924, where Mr Davenheim walks to the post office and vanishes.  However, there is a lake, a path, a gate, and beyond it, a lime kiln.  Ah.  This is how a body can be disposed of – throw it into quicklime which will dissolve everything except Mr Davenheim's distinctive gold and diamond ring – well, it didn't happen that way, but it does indicate that lime kilns were local, ubiquitous and in use.  Every town, every estate, every builder probably had one, for lime is essential for all cement work: mortar, parging, grout, stucco, pathways, foundations, floors.  It was also used as fertilizer and so essential to agriculture.

I'm closing in on the process: you burn limestone, or calcium carbonate (CaCO3), which gives you quicklime, or calcium oxide (CaO).  You mix quicklime with water to get slaked lime, or calcium hydroxide (Ca[OH]2).  This is used in cementitious building products, including whitewash, which is slaked lime and chalk.  Over time as slaked lime dries and hardens, it loses water and absorbs carbon dioxide from the atmosphere, reverting back to limestone.   What a process.