Very happy to report that I’ve accepted an invitation to join the University of Illinois’ School of Architecture as a Visiting Professor for the 2022-2023 academic year. Champaign-Urbana will be a great base camp as Chicago Skyscrapers, 1934-1986 finishes up–the School is just a few blocks from its publisher, the University of Illinois Press. Once the book is out in the world I’m hoping for many opportunities to talk about it in and around Chicago, which will be a short train ride away.
A short ride and a familiar one. Illinois is my alma mater and Champaign-Urbana is where I grew up. That train ride was a key element in early, formative trips to Chicago, and it’s been an enjoyable reprise to take it down to campus for studio reviews over the last few months. Those reviews have featured great work and Temple Hoyne Buell Hall has been full of impressive energy each time. I’m looking forward to being a part of that, teaching alongside some good friends and at least one of my undergrad professors, as well as completing the new book in particularly appropriate surroundings.
Our rough schedule for the Structures Zoo course is to go from heavy to lightweight, introducing students to more and more exotic structural types as we go (sort of like going from the goats in the petting zoo up through the penguins, orangutans, and eventually the lions…) We’re closing in on the end of the semester, and the last lab or two should be doozies, but the more recent one definitely turned a corner as we went from membrane structures to what I think of as networked structures.
The paradigm for these is the geodesic dome, invented by (or, really, rediscovered, packaged, and marketed by) Bucky Fuller. The evolution of the dome through his initial attempts at Black Mountain College (and, I think, at Chicago’s Institute of Design, but that’s another post), shows a gradual refinement from structures based on flat members arranged in “great circles” that failed, to geometric patterns that arranged nodes around a spherical surface, connected by multiple linear elements. The result was a structure with vast redundancy–like a monolithic concrete structure, a true geodesic presents a nearly incalculable number of potential paths for gravity and lateral forces to take. As a result, it functions very much like a shell structure, but with nearly all of the weight removed.
Exotic enough, but all of those elements are sized to take either tension or compression. A particular variant of the geodesic experiments, (pictured at the top) involved figuring out how to organize the linear elements so that compression and tension could be isolated–in other words, placing the heavier, compressive elements only where they were needed and rendering the rest of the dome in thinner, lighter, tensile elements–cables.
The instigator of this idea was Kenneth Snelson, who went on to a career as a sculptor and consultant for all sorts of projects employing this principle. But Fuller also co-opted it, calling it “tensegrity” and (depending on who you believe) claiming it as his own. While geodesics were a bigger business success, tensegrity ranks higher on the exotic structures spectrum because of the uncanny openness the principle creates:
Super weird-looking, right? But also completely stable. If you start at the base, you can see that the structure is based entirely on triangulation–think of it as a three-dimensional truss. Each compression element has its ends stabilized by three cables, fixing those two points in space. As long as you can trace those cables through other, similarly fixed points back to the foundation (the nice, boring equilateral triangle at the bottom), the whole thing is stable–at least mathematically.
So, on the desktop, using wood stirrer sticks for compression elements, regular string for tension, and duct tape to make joints, you can very quickly and simply build a network of triangulated members, finding stability where you can and fixing points by watching where the structure is floppy or where it feels fixed. Student teams started with sterilite boxes, and quickly realized that the secret to building these is that you have to go down to go up–that some tension elements want to pick up gravity loads by reaching down (thus ensuring that they’ll always be in tension), while you can use the compression elements to gain height–with impressive results. A second ‘family’ of cables stabilizes the compression elements’ upper ends, fixing points of triangles to give the whole structure geometric stability.
One team went with a precedent study, building an analogue version of the structure that held up the (now-demolished) Georgia Dome. You can see the “go down to go up” principle at work here as the structure “climbs” a series of (red) compression elements to gain height. Again, there’s some missing rigidity in the short axis, but they’ll get there.
These get impressive pretty fast–here’s Rob admiring that first team’s finished product, a cathedral-like tower of sticks that seems to float almost by magic, even if you know the trick (also, in the background, ace knitterbot sculpture by ace ISU digital fabrication team, for inspiration).
The Georgia Dome is still among the best examples of the principle at work in practice, and its limitations are apparent when you start poking at these models–even with all of the triangulation you’re dealing with inherently flexible structures, and once you realize that you have to design for wind-related lateral forces and uplift in addition to gravity the deflection issues get more difficult. But the results are, to say the least, visually compelling, and tensegrity’s material efficiency is remarkable.
So, what’s lighter than light? That’s this week’s lab…
In post-Nervi lecture Q&As, this question almost always comes up: what made his work so architecturally distinctive? My answer is that Nervi not only designed the structure of his buildings, he also designed the process (thus the subtitle of the book). In particular, since he was the contractor for most of his early work, he sought ways to reduce his costs by breaking down the large spans he built into smaller elements that could be fabricated by relatively unskilled crews, usually in parallel with excavation and foundation work. Distilling structural form into pieces that could be made and, more to the point, placed by small crews kept his equipment overhead low and it allowed him to telescope construction schedules. But it also imprinted his buildings with a definite grain; if all of his pieces were made at a human scale, their agglomeration into a long span would, inevitably, also express that human scale.
In short, I like to say, Nervi’s structures may have been large, but they were productively simple; in fact, if you had enough space and enough time, you could build the Turin Salone B (above) in your backyard–the basic units were made using the simple process of ferrocemento, or light cement troweled onto cages of steel mesh, and they were designed to be light enough that they could be hoisted into place by three or four laborers and a winch.
That combination of process and product has served me well as a great teaching example and, teaching a structures elective with Rob Whitehead this semester, we had the chance to put it into actual practice. Instead of building a full scale version in the parking lot (someday…) we decided to have two teams see if they could replicate the process at two smaller scales; one team fabricated 1/8 scale ferrocement elements with materials from the local hardware store, while the other used 3D printing to produce smaller scale elements, which they assembled during class in a piece of performance art/architectural gymnastics.
Ferrocement proves to be a lot like a loaf of bread: remarkably easy to make a good one, really hard t make a great one. This group got a lot right, making a mold out of foamcore and bending mesh over it–a pretty precise analog to the actual fabrication process that Nervi’s crews used. Quikcrete proved to be tough to work with, though, as it cured too quickly to get good finished edges or to get a full piece made monolithically in one attempt. But the process was fast, and as you can see from the structural test, they were both light enough to assemble by hand and robust enough to at least handle their self weight and resulting thrusts (assuming proper buttressing–Tara is doing a good job there…) Their appearance bothered some of the team, but the actual Nervi units were surprisingly crude, not all that dissimilar from the finish (or lack thereof) here–but they cleaned up well with a coat or two of plaster and paint on their undersides.
The modeling team had the advantage of farming out their fabrication to the school’s 3d printers, but they ran into similar fabrication issues that were analogous to real on-site problems. It took a few tries to get the orientation right (note the incomplete ones in the back), and to get them produced in a reasonable amount of time–the first efforts took something like eight hours to fully print. Getting the time-per-piece down was key to getting them all ready for class, in the same way that simplifying the algorithm in the job site yard was vital to getting hundreds of ferrocemento elements produced just in time to start hoisting them into place.
Our plan had been to have one team assemble a wooden centering that would replicate the traveling scaffold that Nervi used to hoist and place the units, but Nervi didn’t have to deal with errors in scaling in Rhinoceros, so while there’s a beautiful piece of centering in the pic above, it ended up being purely ornamental. We did have a team pour the buttresses while the 3d printing was going on–telescoping the assembly time–and at this point sort of considered delaying the assembly until we could get the scaffolding done to the right scale. Fortunately, the printing team had come up with a snap-tite connection detail in the units that allowed them to assemble multiple elements “off-site,” giving them just enough structural integrity that they could snap larger pieces onto the buttresses–no centering needed (or, really, human centering applied). It took a couple of tries, but once the pieces were all in place the resulting arch was just monolithic enough that it stood on its own, and even survived some tentative testing.
We’ll call it a modest success–certainly an accurate analog to one slice of the Turin hall, and (we think) a valuable lesson in how process–fabrication and assembly–influence and sometimes determine structural form, alongside actual statics. Lots that we would/will change for the next iteration–better cement, more attention to getting the centering right, and maybe jumping scale. Still, certainly proof of concept in that this structure–seventy plus years old at this point–has much to teach.
The best part? I’d given the class a line about making an “IKEA drawing,” or an instruction sheet, for how the process would work–based on the illustrations done by a then-grad student for the book. And did they take the opportunity and run with it? They did.
Not even kidding–my research is featured in a Vox news video this morning about the history of insulated glazing. Solid summary of one of my favorite deep dives over the last few years, and the production beats out my usual slides by a mile…(Also: There are penguins).
After ten years, things have cycled around to give my colleague Rob Whitehead and me half-course elective slots at the same time, so we’ve pooled our resources and put together what we’ve always talked about as our ideal structures class–one long session every Friday morning dedicated to hands-on structures labs. These have always been our favorite parts of teaching structures and, we think, the most effective since they get concepts off of the whiteboards and out of the textbooks and put them into the real world. Breaking stuff and getting students to talk about how and why failures happen is inherently messy and something of a tightrope act, but that mimics the real world, where nothing is ever quite as pure as the formulas make it seem.
Structures Zoo has been colossal fun to scope out and start to put together. We had our first class yesterday, which was basically our thesis statement–that structural knowledge and awareness comes from our interaction with the actual world, and that we make the most progress (as a species and/or as students of the discipline) when we take a rigorous approach to assessing what works and how. We set the first class up as a structured set of four labs, each tied into the history of the deflection formula. Starting with Archtyras and Archimedes, there’s a very neat history-of-science approach to how we understand the deformation of a beam under load–I’ve written before about using this as a way of showing that structures has always been a scientific enterprise, subject to revision and addition as new technology (including Arabic numerals, algebra, calculus, etc.) has come on-line.
The final lab of the day tried to drive home how efficient the scientific method can be, and how quickly it can produce actionable and testable knowledge. The “E” in the formula above is Modulus of Elasticity or a numerical measure of stiffness (also called Young’s Modulus). That’s an intimidating name, but it’s really just a simple ratio of stress to strain–in other words, how much a material deforms under a given load.
In column theory this is most useful in helping to understand how a “long” column will buckle–you want a stiff material that will resist the tendency to get out of the way of a load and start a death spiral of deflection, increased bending forces, further deflection because of those forces, and failure. But in “short” columns–those not vulnerable to buckling because of their stout, hockey-puck-like proportions–“E” is really simple to measure if you have an accurate enough rig.
Or a squishy enough material. If you’re trying to do deflection calculations on steel, you’re dealing with a Young’s Modulus of something like 29,000,000psi. Here at Big State U., we do not have testing rigs in the Architecture department that can impart millions of pounds of pressure, so we have to scale things down. As it happens, there’s a very convenient kitchen staple that can put us in the desktop range of deflections and loads quite easily:
Jello’s natural squishiness (or, in technical terms, very low Modulus of Elasticity) means that it deflects enough to assess with a tape measure and some light weights. We fabricated columns with various concentrations of gelatin (Disclaimer: actual Jell-O is engineered for a much softer mouthfeel, making for an unworkable column, so we switched it up and went with Knox unflavored gelatin instead), all using high-tech formwork (yogurt tubs with the surfaces oiled for easy removal) that produced nice round columns of equal diameter:
To test them, we simply placed one-pound (ish) cans on a bearing plate that let us measure the height of the columns before and after loading. Adding weights one at a time let us plot a rudimentary stress/strain curve. In an ideal world, the slope of that curve is equal to the Modulus of Elasticity, and a simple calculation lets us put a number to that figure.
And, of course, we loaded them to failure, giving us a yield stress that marks the top of the curve:
Depending on the quantity of gelatin in the column, we got Modulus of Elasticity figures ranging from .8 psito 5.4 psi*, but the shape of the curve was interesting–those figures were the average of a slope that changes from a shallow slope to a steeper one. What that means is that the columns deformed more under the initial load, and underwent some kind of “strain-hardening” as loads increased–they got stiffer under higher loads. We hypothesized that this was due to the colloid nature of the gelatin, since the initial loading pressed excess water out of the material. As that water was pressed out, the material consolidated a bit and got tougher to compress. Further research may be necessary.
Doubling the quantity of gelatin made for a pretty stiff column (relatively speaking), but also a strong one–in addition to deflecting the least, it held the final test weight of 15 pounds without failing. Generic blueberry “gelatin dessert” didn’t do much as an additive, as you can see on the right.
All good fun, but with a point. The math behind our most common structural situations can get pretty simple, and the same forces that govern our largest structures can be observed and played around with at any scale. Similarly, we’re able to change any number of variables when we’re building–shape, scale, and material–but we only know how those changes impact what we’re trying to do by testing them out. And, finally, we’re firm believers that while knowledge can come out of textbooks and formulae, wisdom only comes out of taking those ideas into the real world and seeing where they work and what their limitations are. Hoping to take those principles into our weekly Friday sessions each week this semester…
*When we first thought of jell-o columns we were convinced it was an original idea, but a quick online literature search turns up numerous other efforts at determining the material properties of gelatinous desserts. We’re pleased to report that our measurements support conclusions reached by other squishy-column researchers…we stand on the shoulders of giants, etc., etc.
There aren’t many figures who span both of Chicago’s great historic skyscraper eras. The twenty-year commercial hiatus between 1934 and 1955 meant that lots of careers ended, or got their start, between the Field Building and the Prudential–few figures had the longevity or the timing to design in both.
Except for Al Shaw (1895-1970). Shaw was a Boston native, educated at the Boston Architectural Club. After serving in the Army Signal Corps during WWI he worked in Boston before coming to Chicago, where he joined Graham, Anderson, Probst, and White in the mid-1920s. Shaw was a formidable draftsman and designer, and he immediately took on some of the firm’s largest works in the wake of longtime chief designer Peirce Anderson’s death; he was chief designer for the Pittsfield Building, the Civic Opera, the Merchandise Mart, and the Field Building, as well as Philadelphia’s 30th Street Station, all of which featured sharply delineated vertical patterns ornamented in styles ranging from Beaux-Arts classical to moderne. He relied in part on the expertise of the more senior Sigurd Naess (1886-1970) to develop these. After Ernest Graham and Howard White died within weeks of each other in 1936, Naess and Shaw teamed up with the firm’s managing partner, Charles Murphy, to start Shaw, Naess, and Murphy, which rode out the last years of the Depression with industrial and institutional work, including DePaul’s O’Connell Hall and a three-story “taxpayer” building on the site of Burnham and Root’s demolished Masonic Temple, at Randolph and State–an early project of developer Arthur Rubloff.
The trio lasted for ten years, finally splitting up in 1947–in large part due to Shaw’s tempestuous personality, according to Murphy’s later recollection. Shaw was well-connected to Chicago’s art and social circles, though, having married Rue Winterbotham, heir to a barrel-making fortune and a major figure in the city’s cultural scene, in 1932. Shaw joined forces with structural engineer Carl Metz and mechanical engineer John Dolio, debuting with the moderne Florsheim Shoe Factory, on the block just north of Union Station.
The new firm designed industrial and retail buildings in its early years, including the Woolworth store on State Street downtown, which borrowed the vertical limestone striations of the Field Building, albeit at a far more modest scale. Like many fledgling Chicago firms in the late 1940s, though, Shaw, Metz, and Dolio concentrated on the surging residential market, designing seven walkup apartment blocks at Cottage Grove and 84th sts. that took advantage of a new FHA mortgage insurance program and designing a demonstration house in Lincolnwood that highlighted the battle between building trades in the Chicago Building Code debacle that occupied much of the late 1940s.
The firm’s growing residential expertise led to three commissions for apartment buildings along Sheridan Road in Lakeview East, all developed by John Mack and Raymond Sher with financing from Prudential, which like many insurance firms was pouring the proceeds from the postwar demographic boom into real estate and commercial properties through American cities. The first of these, at 3100 N. Sheridan, set the model for the firm’s early high-rise residential design, featuring long, horizontal strip windows set between simple brick spandrel walls, while the last–just two blocks north, between Sheridan and Lake Shore Drive at Belmont, arranged units around short, stub corridors and multiple elevator cores that allowed every unit to occupy the slab’s full width and, thus, to have both lake and city views.
Mack and Sher built on the success of this residential cluster, ultimately hiring Shaw, Metz, and Dolio for four large complexes that punctuate Lake Shore Drive today. The first of these, at Irving Park (3950 N. Lake Shore), adopted the horizontal strip windows of the earlier slabs, but for the subsequent projects Shaw adopted his earlier preference for stark verticality, rendering these in contrasting stripes of white face brick and windows with dark spandrel panels. 3600 N. Lake Shore, at Addison, was the paradigm of this approach, employing newly available low-profile air conditioning units to allow for larger window units in two parallel slabs set–counter-intuitively to some–perpendicular to the lakefront. This arrangement allowed Mack and Sher to claim lake views for all of the complex’ units, even if only the end apartments actually faced the lake itself.
More immediately recognizable were the two single slabs the firm designed for Mack and Sher along the Drive in 1962, at Belmont (3950 N. Lake Shore Dr.) and North (1550 N. Lake Shore Dr.). These were, again, set perpendicular to the Lake, and each one featured a signature metal enclosure around its rooftop mechanical plant, along with emphatic vertical striping.
These projects appealed to singles and families alike—3950 N. Lake Shore housed “mostly” families when it opened, drawing tenants for its “ranch house” like units and its location, just “10 to 15 minutes” from the Loop by car. But the firm also began drawing larger commercial clients, in particular United Insurance, a family-owned Chicago company that had found a niche by offering weekly premium plans to working-class clients. Shaw designed a 40-story tower for United’s highly visible site, at State and Wacker, that featured continuous stripes Georgia marble and recessed, black Vitrolite spandrels–repeating, more or less, the aesthetic formula of the later apartment buildings and making the building the “tallest marble structure in the world” when it opened in 1962.
The firm’s now trademark, gleaming white version of Shaw’s earlier moderne styling found its way to apartment buildings and commercial structures throughout downtown and along the Drive: the Continental Hotel and 777 N. Michigan, at the north end of the Magnificent Mile, were just two of the most visible examples of this formula (and they were–nearly–joined by a third Shaw building between them in an unrealized scheme for the site that became the John Hancock Center).
But the firm’s success was tempered by failure and calamity. The firm’s design for the first McCormick Place, finished in 1960, was widely seen as a grotesque intrusion on the lakefront; its lack of sprinklers contributed to its destruction by fire in 1967. Worse, Shaw took on public housing projects for the CHA that proved disastrous, including the Robert Taylor Homes. Their track record with CHA projects had already been mixed; their designs for the Grace Abbott Homes, at 14th and Loomis, were compromised by shoddy workmanship. The Taylor Homes were beset by budget cuts that made for grossly inadequate elevator service and a program that called for an unrealistically large percentage of large family units. As a result, the towers’ plans were too deep to provide the ‘eyes on the street’ that had made an earlier generation of gallery apartment projects workable. Long wait times and a lack of visibility made the elevators magnets for petty crime and, eventually, assaults.
Dolio left the firm in 1959 and Metz in 1966. Shaw’s son, Patrick, joined the renamed Alfred Shaw & Associates, and carried on work that continued to translate the father’s trademark vertical striation in new materials–55 E. Monroe, for instance, which employed a block-long facade of aluminum mullions that produce that building’s corduroy-like effect along Wacker. Alfred Shaw died in 1970, ending a career that had spanned styles, building types, and eras, a spread that was equaled only by his former partner, Charles Murphy.
AIA Directory of Architects, 1962.
“Architect Alfred P. Shaw Dies.” Chicago Tribune (1963-1996), Dec 02, 1970, pp. 5.
Chappell, Sally A. Kitt, Architecture and Planning of Graham, Anderson, Probst and White, 1912-1936: Transforming Tradition (Chicago: University of Chicago Press, 1992), 259-281.
“Florsheim Shoe Will Construct 7 Story Plant: Output Facilities, Offices to be Included.” Chicago Daily Tribune, Oct 12, 1947, pp. 1-nwB.
Ernest Fuller, “Turn Ground This Week For 640 Flat Unit: Building To Cost 12 1/2 Millions.” Chicago Daily Tribune, Apr 19, 1959, pp. 1-a9.
Gavin, James M. “Shaw Metz Ledger Compiled in 18 Years: Shaw Metz Achievement Ledger Big.” Chicago Tribune, Jan 26, 1964, pp. 2-f1.
Charles Gotthart, “Unions, Realty Men Test New Home Methods: Model House to Aid Community Fund.” Chicago Daily Tribune, Oct 23, 1949, pp. 1-b9.
“Redesign, Loop’s Newest “Taxpayer”.” Chicago Daily Tribune, May 21, 1939, pp. 1-b8.
“Reveal Shoddy Work On New Housing Units: Two Contracting Firms, Architects Blamed.” Chicago Daily Tribune, Sep 15, 1953, pp. 7.
“Three Form a New Firm of Architects.” Chicago Daily Tribune, Dec 13, 1936, pp. 1.
Architecture Twitter has been ablaze this week with news that billionaire Charlie Munger has solved UCSB’s housing crunch with a proposal for a 1.68 million square foot largely windowless dormitory that will house 4096 students and that he, wait for it, designed himself. The campus’ Chancellor called it “inspired and revolutionary.” An architect on the University’s design review committee resigned in protest.
It has been pointed out that the Unite, like most housing, was subject to code regulations about light and air. Most cities have requirements that all living spaces have direct access to natural daylight and ventilation–which explains the walls in many apartment conversions that don’t go all the way to the ceiling, “borrowing” light and air from adjacent, windowed spaces. Technically, you could argue that these are outdated. They’re mostly from an era of tenement reform, when cities were finally cracking down on landlords who carved existing buildings into dangerous rat’s warrens of corridors and dark rooms that were fire hazards as well as being genuine public health problems–stale, unmoving air in crowded apartments during an era when tuberculosis was rampant was a recipe for contagion.
Dirty little secret: many state universities are actually exempt from local building codes since municipalities generally can’t override state regulations. Instead, campus buildings are often subject to less stringent state codes. So even if Santa Barbara does have light and air requirements, the University may not have to follow them. There’s still plenty of good research that shows correlations between connections with outside and mental health–of particular concern among college students these days. Munger’s response? “We want to keep the suicide rate low.”
So, that’s OK then.
Still, some have wondered, isn’t this a firetrap? Those long corridors, and, according to initial press reports, only two entrance doors? Well, eyeballing the plans, it looks like this would be code-legal. The two general principles of life safety are providing two exits from significantly occupied spaces (often portion of a building occupied by more than fifty people) and having exits or protected fire stairs no more than 300 feet from any space (in a building with sprinklers–much less in one without). Munger’s plan divides the floors into eight “houses” of eight suites, each with eight rooms (I have a suspicion there’s some amateur numerology at work here, but that’s for another post…). Each suite can exit in two directions through the long E/W corridors, which feed into the common rooms on the exterior and the “Main Building Corridor” in the center. Fire stairs in both locations lead to exit doors that open directly outside.
Code legal? Quite possibly. But there’s meeting the code, and then there’s good life safety design. Panicking humans are notoriously bad at finding exits, even clearly-marked, logically-placed ones. In general, we try to spread fire stairs out so that they’re at the extreme corners of a building so that once you’ve blindly run as far as you can, you’re taken care of. The stairs in the center corridor do that, but the ones on the exterior leave large open spaces in the common room that you can imagine filling up with confused, panicking students. But, OK, let’s give Munger that one. If he can sleep at night knowing that the fire exiting strategy meets minimum standards, great.
What I haven’t seen any analysis on, though, is the other big circulation oncern in multi-story buildings. This “monster” would have 4,096 bedrooms/occupants. All of them would be college students, getting up and going to class at more or less the same time every morning. How do eight floors of students, all rushing to class, get out of the building?
Hotel design has a well-known standard for elevator provisions–one cab for every 75-80 rooms. That’s for a building full of people on vacation, getting up at various times during the day, or a very gentle “peak load.” The number of cabs is the driving factor in wait and trip time. What slows elevators down are trips with multiple stops, since the time it takes for doors to open, passengers to embark or disembark, and doors to close is fixed, and usually more than the travel time from floor to floor. More cabs mean more single trips, which means more efficient operations in terms of wait time. What’s an acceptable wait time? Studies have shown that for Americans, 45 seconds is intolerably long to wait for an elevator.
That provision is confirmed by a rabbit hole I went down doing the latest skyscraper research. The social failure of Chicago’s Robert Taylor Homes was often blamed, at least in part, on their incredibly sparse elevator provisioning. Originally designed with three shafts for each tower of 450 bedrooms, that was cut at the last minute to just two, which led to wait times of up to five minutes–when both were actually working. Residents heading out–often with cash on them to go shopping–became easy targets for muggers and, eventually, gangs. That ratio, of 225 bedrooms to one elevator, was nearly three times that of typical Lake Shore Drive apartment towers, which had a hotel-like 80-85 bedrooms for every cab.
Munger Hall? Well, the plan above shows 12 elevators, which makes for a bedroom/cab ratio of 341:1, more than 50% greater than the failed Taylor Homes and suggesting wait times of 7-1/2 minutes under normal circumstances. Add the morning class rush and that could be even higher.
The punch line? Munger proposes a full-fledged shopping center on the dorm’s top floor–Costco and all. Retail populations are typically spread out during the day, but they’d add to that already unprecedented elevator load. Worse, if you look closely you can see that two of those twelve elevators are actually larger–the only freight elevators in the complex. I’m not clear on how trucks would unload their palettes of 5-gallon Costco mayonnaise barrels into those, but having to haul a full shopping center’s worth of freight up a single pair of what look like Class-A elevators would take a good couple of hours. Multiply that by a full complement of stores and those two would be in use all day during the week, leaving students and customers to just the ten regular passenger elevators.
There’s a good reason that we put retail and entertainment facilities on ground floors–it takes a lot of elevator capacity to move crowds and freight up in the air. Munger may well be correct in his opinion that “architects don’t know sh*t,” but at least a few of us have been in that meeting with an elevator consultant where the physics of vertical transportation and the impatient emotional DNA that underlies the typical American passenger collide…
Taking a bit of a break from Chicago to read up on some early 19th century wrought and cast iron reading, and finally decided to plow through Peter Berlyn and Charles Fowler’s account of the design and construction of the Crystal Palace, an exhaustive (and exhausting) monograph put out just after the structure’s opening in 1851. I’d been curious about the trusses that spanned the relentless 24 foot planning module–they were cast iron, with connections to the columns made with pegs and shims (!). The longer spanning girders over the main nave, however, were wrought iron, which checks out–the 1840s saw that material come on line as a viable solution to spanning structures. (You can tell the difference in the engraving above if you look closely–the trussed girders to the left are clearly cast iron, bulky in proportion, while the high girder on the right, where the transept vault sits, is made up of thinner elements that could only be rolled, not cast).
Anyway, the Crystal Palace is sort of a running joke in Construction History as the “first everything,” at least if you’re British. First curtain wall? Crystal Palace. First fully industrialized building? Crystal Palace. First skyscraper? Crystal Palace. But it certainly earned its accolades–there are legitimate arguments to be made for all of those, even that last one. One way that I’d never thought of the structure being modern, though, is described brilliantly by Berlyn and Fowler early on in their design history. Joseph Paxton, after touting his idea for a mass-produced filigree of iron and glass in the London Illustrated News, joined forces with contractors Fox and Henderson just days before tenders were due for the project. While his basic scheme was as simple as it could be–just a handful of components repeated hundreds or, in some cases, thousands of times across the sixteen acre site–having confidence in the abilities of iron, glass, and timber manufactures to produce that much material in northern factories, deliver it to London in time to construct the building in just a few months, and to price it reliably, relied on technology of a far different sort:
“It was now Saturday, and only a few days more were allowed for receiving tenders. Yet before an approximate estimate of expense could be formed, the great glass-manufacturers and iron-masters of the north had to be consulted….But in a country of electric telegraphs, and of indomitable energy, time and difficulties are annihilated; and it is not the least of the marvels wrought in connexion with the great edifice that, by aid of railway-parcels and the electric telegraph, not only did all the gentlemen summoned out of Warwickshire and Staffordshire appear on Monday morning at Messrs. Fox and Henderson’s office in Spring Gardens, London, to contribute their several estimates to the tender for the whole, but within a week the contractors had prepared every working drawing, and had calculated the cost of every pound of iron, every inch of wood, and of every pane of glass.”
A first instance of Building Information Modeling? I’ll let a U.K. partisan make that argument, but it’s clear from that description that, without the telegraph and railways annihilating “time and difficulties” Paxton’s scheme could never have come together in the time it did. The railway required and inspired development in the iron industry, but easing the flow of information between manufacturer, designer, and contractor isn’t one I’d thought of before…
It was a great thrill yesterday to take part in a Construction History Society of America webinar (credit-free learning!) with David Macaulay, one of my all-time heroes and the author/artist behind many great books that shaped my childhood. Many thanks to Peter Hilger, Melanie Feerst, and the staff at the University of Minnesota for hosting.
My contribution was a quick preview of one emerging theme in the new Chicago book–the “secret history” of SOM’s tube structures. The standard story is fairly well documented–Fazlur Khan is credited with naming the structural type, if not exactly inventing it, and there’s a very clear progression of the idea from the Brunswick and DeWitt-Chestnut buildings of 1961-65 through the world-beating Hancock and Sears Towers a few years later. The basic idea is to think of high rise structures as “super-columns,” pushing all of the structural material to the perimeter of the floor plate so that it gains maximum resisting leverage over wind forces. The analogy I use in class is a paper towel roll. It will take far more axial compressive load in when intact than if you slice it down the side and roll it up into a tighter cylinder, since shortening the resisting moment arm makes it far more vulnerable to buckling.
Brunswick was a cautious step in that direction, but it paired perimeter structure with a traditional shear-core (the green walls in the model above by ace undergrad research assistant Jack Strait). One key to its performance is that the perimeter columns in plane with the shear walls (red in the model) are deeper than their neighbors, reflecting the concentration of loads being transferred from the sail-like exterior walls to the upturned-beam like interior core. Dewitt-Chestnut, on the other hand, was a pure tube structure, with irregularly-placed columns in the center of its floor plate that handled gravity loads only, leaving the perimeter to carry the entire wind load:
I’ve posted elsewhere about I.M.Pei’s proto-tube structures in New York and Chicago–the precursors to Brunswick, according to Bruce Graham. I made that point, and showed how construction improvements led to another set of tube structures that enclosed apartment and condominium buildings throughout Chicago, by the firm of Dubin, Dubin, Black, and Moutoussamy that deserve far more attention than they’ve typically received. But a friendly email from a regular Architecturefarm correspondent this morning points out that I didn’t get to one of Chicago’s biggest–and purest–tube structures, one with a legacy that stems directly from SOM’s work.
Standard Oil was designed by a pair of firms–Edward Durrell Stone from New York and Chicago’s own Perkins + Will. After the Hancock was completed, P+W hired away one of SOM’s lead engineering partners, Al Picardi. At the time of the Hancock, Fazlur Khan was still a relatively junior member of SOM’s office, having joined in 1955. Picardi was more senior and was in fact the lead engineer on Hancock–Khan reported to him. He switched firms, apparently, to lead the engineering of Standard Oil, which from its inception was intended to be colossal, at over two million square feet (far larger, incidentally, than the original masterplan for Illinois Center, which at first included Standard Oil’s site…)
Picardi’s structural system is a clear adaptation of the tube structure to Stone’s heavy-handed massing. The perimeter is composed of hollow, triangular steel columns tied into deep edge girders, while the interior structure is gravity-only columns concentrated in the core. The result is clear span office space and–a Stone trademark–narrow slit windows with starkly vertical proportions.
In addition to the large, clear span floors, the structural advantage to this was a core unconstrained by large shear walls and a lightweight spanning structure. With the building’s stiffness taken up entirely by the exterior, the interior structure could be made of light, open-web steel joists:
Standard Oil’s structure was a successful application of the tube to another tall building–Leslie Robertson engineered a similar pairing of stiff, tightly spaced exterior columns with long span open web joists for New York’s World Trade Center at around the same time, which was further proof-of concept. But the building was an architectural disaster–in addition to being wildly overscaled for the emerging Illinois Center district, Stone’s trademark vertical style struck many as alien to Chicago, where skyscraper facades were known more for their rich interplay of verticals and horizontals. Like many other tube structures, Standard Oil hit the ground with a thud–the need to bring so many tightly spaced columns all the way to the ground proved difficult for nearly every architect, but many got the sense that here, Stone didn’t even try, simply filling in the narrow interstices with glass revolving doors that proved treacherous during downdraft winds.
Stone himself gave the building a luke-warm reaction, remarking only that “it’s good looking” on seeing the project firsthand. The Tribune’s Paul Gapp, on the other hand,was furious. “The Standard Oil Building,” he wrote, “is perhaps the worst thing that has happened to Chicago’s skyline in the last 30 years.” The Prudential’s “headstone by the Lake” was now matched, in Gapp’s view, by Stone’s scale-less, “unbroken verticality.” Its blazing contrast between brilliant white marble and the narrow, dark recesses hid any sense of floor-to-floor rhythm or Picardi’s ingenious structural fabric behind facile elevational stripes. “If you stare at the building from a short distance for more than 15 seconds,” Gapp complained, “it is almost disorienting.”[i]
[i] Paul Gapp, “Ambiguous Statement Snarls Center Debate.” Chicago Tribune, June 30, 1974. 1-e3.
The Chicago project is taking a breather while I get ready for the semester, and in the spirit of constant improvement, I’ve been rewriting the syllabus for Big and Tall: A History of Construction from the Pyramids to the Burj, which I’m teaching this Fall for the first time in a couple of years. The first couple of thematic lectures, on ancient timber and stone construction, have always relied on Vitruvius and the Yingzao Fashi, a 12th century Chinese treatise that was a combination of Sweet’s Catalogue, MasterSpec, and the International Building Code.
Inspired to dig a little deeper into Roman sources, though, I’ve discovered Pliny the Elder, whose Naturalis Historiais a thorough (and gloriously grumpy) chronicle of, well, the whole known world in 70 CE or so. Among his thoughts on building is a recognizable plea for a more sustainable approach to construction and an agonized accounting of the widespread pillaging caused by quarrying:
“Nature made mountains for herself as a type of bond for compressing the bowels of the earth and at the same time for holding in check the rushing strength of rivers and breaking the waves of the sea and to restrain with her hardest substance her least quiet parts. We quarry these mountains and drag them away for no other reason than that our pleasure dictates it—mountains which it was once astonishing even to cross. Our ancestors considered it almost a portent that the Alps were climbed by Hannibal and later by the Cimbri: now these very peaks are quarried into 1000 types of marble. Promontories are laid open to the sea, and nature is made flat. We carry away features, which were meant to serve as barriers for keeping nations apart. Ships are built for the sake of transporting marble, and so here and there over the waves, the wildest portions of nature, are carried mountain peaks….Each of us who hears the price of these items and sees the massive quantities, which are being dragged around should meditate on how much better life would be without them. Oh, that men should do these things—or rather, endure them—on account of no other purpose or pleasure than to recline surrounded by varicolored stones!”
–Pliny, Natural History, 31.1-3
The hubris that went into laying promontories open to the sea and the call for simplifying, downsizing, and thinking about whether the ability to topple mountains means that one should do so rings pretty true today.
But Pliny also found quotidian examples of the corruption inherent in Imperial construction. Not only were the mountains being pillaged, but client’s budgets were, as well. Here he is describing the process of fabricating marble slabs out of those Hannibal-trod blocks of stone:
“But whoever first discovered how to cut marble and split luxury into sheets showed harmful ingenuity. This seems to be effected by iron but actually is done by sand, as the saw presses the sand on a very narrow line and brings about the cutting by its very passage back and forth. Sand from Ethiopia is rated most highly….Later, a no less esteemed sand was found on a certain shoal in the Adriatic Sea, uncovered by low tide and not easy to spot. But now, deceitful workmen have dared to cut marble with any sort of sand from any river, a source of waste, which very few notice. For the coarser sand cuts less accurate slices, wears away more of the marble, and by its rough finish increases the work of polishing. Consequently, the revetment slabs are thinner. Again, Theban sand is suitable for polishing, and a compound made form limestone or pumice.”
–Pliny, Natural History, 36.51-53
Thinner slabs from cheaper sand…those ‘deceitful workmen’ were basically proposing an unapproved substitution, and I’m guessing that Roman practice and current AIA contract documents both took a dim view of those sorts of shenanigans. You can totally imagine the equivalent of the email to the client: “We have reviewed the proposed substitution of sand from the Tiber and find it unacceptable. The project specifications upon which the workmen’s bid was submitted clearly call for Theban sand, and…”