Tacoma Narrows Bridge

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The Bridge: The Building of the Verrazano-Narrows Bridge by Gay Talese, Bruce Davidson

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delayed gratification, fixed income, New Journalism, Tacoma Narrows Bridge, transcontinental railway

After a re-examination, it was concluded that the Queensboro was inadequate to safely carry its intended load. So the four rapid-transit tracks that had been planned for the upper deck were reduced by two. The loss of the two tracks was compensated by the construction of a subway tunnel a block away from the bridge—the BMT tunnel at Sixtieth Street under the East River, built at an additional cost of $4,000,000. In November of 1940, when the Tacoma Narrows Bridge fell into the waters of Puget Sound in the state of Washington, O. H. Ammann was again one of the engineers called in to help determine the cause. The engineer who caught the blame in this case was L. S. Moisseiff, a man with a fine reputation throughout the United States. Moisseiff had been involved in the design of the Manhattan Bridge in New York, and had been the consulting engineer of the Ambassador Bridge in Detroit and the Golden Gate in California, among many others, and nobody had questioned him when he planned a lean, two-lane bridge that would stretch 2,800 feet over the waters of Puget Sound.

There was also a prewar trend toward economizing on the over-all cost of bridge construction, however, and one way to save money without spoiling the aesthetics—and supposedly without diminishing safety—was to shape the span and roadway floor with solid plate girders, not trusses that wind could easily pass through. And it was partially because of these solid girders that, on days when the wind beat hard against its solid mass of roadway, the Tacoma Narrows Bridge kicked up and down. But it never kicked too much, and the motorists, far from becoming alarmed, actually loved it, enjoyed riding over it. They knew that all bridges swayed a little in the wind—this bridge was just livelier, that was all, and they began calling it, affectionately, "Galloping Gertie." Four months after it had opened—on November 7—with the wind between thirty-five and forty-two miles an hour, the bridge suddenly began to kick more than usual.

pages: 442 words: 39,064

Why Stock Markets Crash: Critical Events in Complex Financial Systems by Didier Sornette

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Asian financial crisis, asset allocation, Berlin Wall, Bretton Woods, Brownian motion, capital asset pricing model, capital controls, continuous double auction, currency peg, Deng Xiaoping, discrete time, diversified portfolio, Elliott wave, Erdős number, experimental economics, financial innovation, floating exchange rates, frictionless, frictionless market, full employment, global village, implied volatility, index fund, information asymmetry, intangible asset, invisible hand, John von Neumann, joint-stock company, law of one price, Louis Bachelier, mandelbrot fractal, margin call, market bubble, market clearing, market design, market fundamentalism, mental accounting, moral hazard, Network effects, new economy, oil shock, open economy, pattern recognition, Paul Erdős, Paul Samuelson, quantitative trading / quantitative finance, random walk, risk/return, Ronald Reagan, Schrödinger's Cat, selection bias, short selling, Silicon Valley, South Sea Bubble, statistical model, stochastic process, Tacoma Narrows Bridge, technological singularity, The Coming Technological Singularity, The Wealth of Nations by Adam Smith, Tobin tax, total factor productivity, transaction costs, tulip mania, VA Linux, Y2K, yield curve

However, the strong wind of that day was only the “local” cause, while there was a more fundamental cause: The bridge, like most objects, has a small number of characteristic vibration frequencies, and one day the wind was exactly the strength needed to excite one of them. The bridge responded by vibrating at this characteristic frequency so strongly, that is, by “resonating,” that it fractured the supports holding it together. The fundamental cause of the collapse of the Tacoma Narrows Bridge thus lies in an error of conception that enhanced the role of one specific mode of resonance. In sum, the collapse of the Tacoma Narrows Bridge as well as that of many stock markets during crashes, is the result of built-in or acquired instabilities. These instabilities are in turn revealed by “small” perturbations that lead directly to the collapse. The speculative attacks in periods of market instabilities are sometimes pointed to as possible causes of serious potential hazards for developing countries when allowing the global financial markets to have free play, especially when these countries come under pressure to open up their financial sectors to large foreign banks, insurance companies, stockbroking firms, and other institutions, under the World Trade Organization’s financial services negotiations.

Within the framework defended in this book, crashes occur as possible (but not necessary) outcomes of long preparation, which we term “herding,” which pushes the market into increasingly unstable regimes. When in this state, there are many possible “local” causes that may cause it to stumble. Pushing the argument to the extreme to make it crystal clear, let us compare this to laying responsibility for the collapse of the infamous Tacoma Narrows Bridge that once connected mainland Washington with the Olympic peninsula on strong wind. It is true that, on November 7, 1940, at approximately 11:00 a.m., the bridge suddenly collapsed after developing a remarkably “ordered” sway in response to a strong wind [418] after it had been open to traffic for only a few months. However, the strong wind of that day was only the “local” cause, while there was a more fundamental cause: The bridge, like most objects, has a small number of characteristic vibration frequencies, and one day the wind was exactly the strength needed to excite one of them.

Productivity: What Is It, and Why Do We Care about It? Working paper of the Federal Reserve Bank of New York. 416. Stiroh, K. J. (2001). Information Technology and the U.S. Productivity Revival: What Do the Industry Data Say? Working paper of the Federal Reserve Bank of New York. 417. Svenson, O. (1981). Are we less risky and more skillful than our fellow drivers? Acta Psychol. 47, 143–148. 418. Tacoma Narrows Bridge historical film footage showing in 250 frames (10 seconds) the maximum torsional motion shortly before failure of this immense structure, http://cee.carleton.ca/Exhibits/Tacoma_Narrows/. 419. Tainter, J. A. (1988). The Collapse of Complex Societies (Cambridge University Press, Cambridge, U.K. and New York). 420. Tainter, J. A. (1995). Sustainability of complex societies, Futures 27, 397–407. 421.

pages: 1,758 words: 342,766

Code Complete (Developer Best Practices) by Steve McConnell

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Ada Lovelace, Albert Einstein, Buckminster Fuller, call centre, choice architecture, continuous integration, data acquisition, database schema, don't repeat yourself, Donald Knuth, fault tolerance, Grace Hopper, haute cuisine, if you see hoof prints, think horses—not zebras, index card, inventory management, iterative process, Larry Wall, late fees, loose coupling, Menlo Park, Perl 6, place-making, premature optimization, revision control, Sapir-Whorf hypothesis, slashdot, sorting algorithm, statistical model, Tacoma Narrows Bridge, the scientific method, Thomas Kuhn: the structure of scientific revolutions, Turing machine, web application

They have been revised and polished until the author has shown us what he wishes he had done, not what actually did happen. —David Parnas and Paul Clements In my part of the world, a dramatic example of such a wicked problem was the design of the original Tacoma Narrows bridge. At the time the bridge was built, the main consideration in designing a bridge was that it be strong enough to support its planned load. In the case of the Tacoma Narrows bridge, wind created an unexpected, side-to-side harmonic ripple. One blustery day in 1940, the ripple grew uncontrollably until the bridge collapsed, as shown in Figure 5-1. Figure 5-1. The Tacoma Narrows bridge—an example of a wicked problem [View full size image] This is a good example of a wicked problem because, until the bridge collapsed, its engineers didn't know that aerodynamics needed to be considered to such an extent.

Avoid Failure Civil engineering professor Henry Petroski wrote an interesting book, Design Paradigms: Case Histories of Error and Judgment in Engineering (Petroski 1994), that chronicles the history of failures in bridge design. Petroski argues that many spectacular bridge failures have occurred because of focusing on previous successes and not adequately considering possible failure modes. He concludes that failures like the Tacoma Narrows bridge could have been avoided if the designers had carefully considered the ways the bridge might fail and not just copied the attributes of other successful designs. The high-profile security lapses of various well-known systems the past few years make it hard to disagree that we should find ways to apply Petroski's design-failure insights to software. Choose Binding Time Consciously Binding time refers to the time a specific value is bound to a variable.

Most people wouldn't want to use their recreational time to scrutinize a 500-page source listing, but many people would enjoy studying a high-level design and dipping into more detailed source listings for selected areas. The software-engineering field makes extraordinarily limited use of examples of past successes and failures. If you were interested in architecture, you'd study the drawings of Louis Sullivan, Frank Lloyd Wright, and I. M. Pei. You'd probably visit some of their buildings. If you were interested in structural engineering, you'd study the Brooklyn Bridge; the Tacoma Narrows Bridge; and a variety of other concrete, steel, and wood structures. You would study examples of successes and failures in your field. Thomas Kuhn points out that a part of any mature science is a set of solved problems that are commonly recognized as examples of good work in the field and that serve as examples for future work (Kuhn 1996). Software engineering is only beginning to mature to this level.

pages: 259 words: 67,456

The Mythical Man-Month by Brooks, Jr. Frederick P.

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finite state, HyperCard, Menlo Park, sorting algorithm, speech recognition, Steve Jobs, Tacoma Narrows Bridge, Turing machine

He will set his direction much more crisply and quickly by doing so. Plan to Throw One Away Plan to Throw One Away There is nothing in this world constant but inconstancy. SWIFT It is common sense to take a method and try it. If it fails, admit it frankly and try another. But above all try something. FRANKLIN D. ROOSEVELT Collapse of the aerodynamically misdesigned Tacoma Narrows Bridge, 1940 UPI Photo/The Bettman Archive Pilot Plants and Scaling Up Chemical engineers learned long ago that a process that works in the laboratory cannot be implemented in a factory in only one step. An intermediate step called the pilot plant is necessary to give experience in scaling quantities up and in operating in nonprotective environments. For example, a laboratory process for desalting water will be tested in a pilot plant of 10,000 gallon/day capacity before being used for a 2,000,000 gallon/day community water system.

Despite its excellencies, I expect the WIMP interface to be a historical relic in a generation. Pointing will still be the way to express nouns as we command our machines; speech is surely the right way to express the verbs. Tools such as Voice Navigator for the Mac and Dragon for the PC already provide this capability. Don't Build One to Throw Away—The Waterfall Model Is Wrong! The unforgettable picture of Galloping Gertie, the Tacoma Narrows Bridge, opens Chapter 11, which radically recommends: "Plan to throw one away; you will, anyhow." This I now perceive to be wrong, not because it is too radical, but because it is too simplistic. The biggest mistake in the "Build one to throw away" concept is that it implicitly assumes the classical sequential or waterfall model of software construction. The model derives from a Gantt chart layout of a staged process, and it is often drawn as in Figure 19.1.

pages: 367 words: 99,765

Maphead: Charting the Wide, Weird World of Geography Wonks by Ken Jennings

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Asperger Syndrome, augmented reality, Bartolomé de las Casas, Berlin Wall, British Empire, clean water, David Brooks, digital map, don't be evil, dumpster diving, Eratosthenes, game design, Google Earth, helicopter parent, hive mind, index card, John Harrison: Longitude, John Snow's cholera map, Mercator projection, Mercator projection distort size, especially Greenland and Africa, Mikhail Gorbachev, New Journalism, openstreetmap, place-making, Ronald Reagan, Saturday Night Live, Skype, Stewart Brand, Tacoma Narrows Bridge, traveling salesman, urban planning

, Highway 99 once ran from the Canadian border all the way to Mexico, but it was decommissioned in 1968 when I-5 was completed, and much of it is now anonymous and unsigned. Roadgeeks are archaeologists as well, finding history in the modern urban ruins. They see the ghosts of Esso stations and motels shaped like tepees where now there’s only a waste-land of pawnshops and adult video stores. The last stop on our itinerary is another historic spot: the famed Tacoma Narrows Bridge, recently twinned with a new span heading west to the Kitsap Peninsula. The original bridge across this strait was the famous “Galloping Gertie,” which collapsed in a 1940 storm. If you were ever in an introductory physics class, you’ve probably seen the famous footage of the bridge wobbling and warbling terrifyingly due to harmonic resonance before it crashed into Puget Sound. The new bridge is reassuringly sturdy.

See a cookbook Snow, John, 59 social studies, 41 South Korea map conflicts with Japan, 62, 72 seen from space, 66 See also Jennings, Ken: in Seoul space exploration, 25–26, 59 Spafford, John, 166–68, 172–73, 182 spatial cognition, 16–29, 51–52, 233 Speer, Albert, 58 Stanley, Henry Morton, 79 Starbucks, 156–57, 164 Star Trek, 112, 197 Stevenson, Robert Louis, 108 Stewart, Isaac, 116–18 Stoppard, Tom, 42 St. Valentine Day’s Massacre (map rally), 177–85 subways, 136 surveyors brave and heroic, 88–89 unpopular and spooky, 63 swastikas, visible from space, 220 Sweden, plotting for world domination by, 136 Sylvie and Bruno (Carroll), 212–13 Taal, Lake, 2 Tacoma Narrows Bridge, 172 Tadataka, Ino, 62 Tallis, John, 97, 104 Tamir, Yuli, 64 Tannen, Deborah, 139 taxi drivers, 17, 236 Teague, Mike, 188–89 Terra Australis, 68, 81, 83 Tharp, Marie, 74 Theatrum Orbis Terrarium (Ortelius), 68 theft of maps, 93–97 Third Culture Kids, 30 Thompson, Almon, 242–43 Thompson, Nephi, 20 Thorpe, Jim, 69 Today (show), 34–35 Tolkien, J. R. R., 114–16, 119 toponyms, 4, 31, 49, 67–74, 219 politically incorrect, 67 risqué, 70–71 sellout, 69–70 topophilia, 14–15, 29–31, 45 Toscanelli, Paolo, 16 travel, systematic, 11, 149–65, 168 cost of, 151, 162–63 reasons for, 151, 153, 158, 160–61, 164–65 Travelers’ Century Club, 149–55, 158, 159–60 Travellers Club, 149 Treasure Island (Stevenson), 108 treasure maps, 62, 248–49 Trebek, Alex, 125–26, 129, 141, 143–45 after a few drinks, 147 civilian wardrobe of, 125–26 triangulation, 88–89 Truth or Consequences, New Mexico, 69 Tuan, Yi-Fu, 14 turtles, 21–23 Ulmer, Dave, 187–89, 191, 194, 201, 202–3, 210 United States Geological Survey, 59, 60, 234 University of Miami, 32–36 upside-down maps, 52–54, 53, 140 Upton, Caite, 38 Useem, Ruth Hill, 30 Utopia (More), 119 Uttal, David, 17–20, 24–25 Vatican Museum, 136 Veley, Charles, 158–62, 164 Vermeer, Jan, 99–100 Vespucci, Amerigo, 75–77, 90, 240 Victoria Island, Nunavut, 2 video games, 112 virtual reality, 225.

pages: 848 words: 240,351

The Great Bridge: The Epic Story of the Building of the Brooklyn Bridge by David McCullough

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death of newspapers, Isaac Newton, Menlo Park, Tacoma Narrows Bridge, transcontinental railway

Roebling in battles taken part in bridges built during correspondence with his wife tunnel at Petersburg and on the war social effects of “Turtles” used in Gen. Warren in Clarke, Thomas C., Jr Clausen, Henry Cleveland, Grover at Brooklyn Bridge inauguration Cleveland Rolling Mill Clifton Bridge (England) Clinton (ferry) Coal mine accidents Cochrane, Admiral Lord Thomas Collapsed bridges, casualties from Ashtabula bridge Quebec bridge Tacoma Narrows Bridge Tay Bridge Wheeling Bridge Collingwood, Francis, Jr Brooklyn caisson and Brooklyn tower accident and footbridge work and New York caisson and New York tower and W. Roebling’s correspondence with at RPI alumni gathering testifies in Miller suit Collins, Charles Colorado Fuel & Iron Company Coman, Thomas Comet (ship) Committee of Investigation (of New York Bridge Company) Competition among engineers Compressed air air system described compressors escape of, while pouring concrete fire in Brooklyn caisson increasing depth and air problems physical derangements caused by pressure required See also Air locks Compressed air “baths” against bends Concrete for Brooklyn caisson compressed air escape while pouring for New York caisson for repairing fire damage Coney Island (Brooklyn) Coney Island Railroad Connolly, Richard B., “Slippery Dick,” breakup of Tweed Ring and Rink Committee investigation and at marriage of Tweed’s daughter Cooper, Edward Cooper, Lucia, see Roebling, Lucia Cooper, Peter Cooper, Theodore Cooperation among engineers Cope (worker) Copeland, William Corliss, George H.

Roebling during Civil War “chain bridge,” first suspension aqueduct poorly built primitive as spiritual or ideal conception very first See also specific bridges Sutter Street Railways Swan, Alden S. Swan, Charles as member of Bridge Party retires J. Roebling and death of Roebling and W. Roebling and Swedenborg, Emanuel Sweeny, Peter (Brains) and breakup of Tweed Ring flees the country Rink Committee investigation and bridge stock and at marriage of Tweed’s daughter Swertcope, John Valentine Tacoma Narrows Bridge (Wash.) Talmage, T. DeWitt Tay Bridge (Scotland) Telford, Thomas Tennessee (ship) Terminals Thurber, H. K. Tilden, Samuel Tilton, Elizabeth scandal involving Tilton, Theodore Timbs, Patrick Titanic (ship) Tombs (N.Y.C. prison), materials used for building Tooker, Commodore Joe Towers Allegheny River Bridge Brooklyn accidents and deaths completing description from top of granite for height of keystone of arch masonry on roadway to tower finished work suspended for winter (1872) working on top years taken to complete Brooklyn Bridge architectural features of.

* With careful editing and numerous annotations she managed to turn a rather dry, colorless diary kept by a Putnam County preacher into an engaging chronicle. She also included an additional chapter on the Warren family. Titled The Journal of the Reverend Silas Constant, it was published in 1903. * All figures are based on the bridge as it was when completed in 1883. * The most famous latter-day example of this same phenomenon was the collapse of the Tacoma Narrows Bridge, over Puget Sound, in the state of Washington. On November 7, 1940, in a high wind, “Galloping Gertie,” as the bridge became known, began heaving up and down so violently that it soon shook itself to pieces. The bridge lacked “aerodynamic stability” the experts concluded, for the simple reason that the necessary stiffness preached by Roebling had been overlooked by the designer. Eyewitness accounts of the disaster are strikingly reminiscent of the one from the Wheeling Intelligencer, written nearly ninety years before

pages: 402 words: 110,972

Nerds on Wall Street: Math, Machines and Wired Markets by David J. Leinweber

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AI winter, algorithmic trading, asset allocation, banking crisis, barriers to entry, Big bang: deregulation of the City of London, butterfly effect, buttonwood tree, buy low sell high, capital asset pricing model, citizen journalism, collateralized debt obligation, corporate governance, Craig Reynolds: boids flock, creative destruction, credit crunch, Credit Default Swap, credit default swaps / collateralized debt obligations, Danny Hillis, demand response, disintermediation, distributed generation, diversification, diversified portfolio, Emanuel Derman, en.wikipedia.org, experimental economics, financial innovation, fixed income, Gordon Gekko, implied volatility, index arbitrage, index fund, information retrieval, intangible asset, Internet Archive, John Nash: game theory, Kenneth Arrow, Khan Academy, load shedding, Long Term Capital Management, Machine translation of "The spirit is willing, but the flesh is weak." to Russian and back, market fragmentation, market microstructure, Mars Rover, Metcalfe’s law, moral hazard, mutually assured destruction, Myron Scholes, natural language processing, negative equity, Network effects, optical character recognition, paper trading, passive investing, pez dispenser, phenotype, prediction markets, quantitative hedge fund, quantitative trading / quantitative finance, QWERTY keyboard, RAND corporation, random walk, Ray Kurzweil, Renaissance Technologies, Richard Stallman, risk tolerance, risk-adjusted returns, risk/return, Robert Metcalfe, Ronald Reagan, Rubik’s Cube, semantic web, Sharpe ratio, short selling, Silicon Valley, Small Order Execution System, smart grid, smart meter, social web, South Sea Bubble, statistical arbitrage, statistical model, Steve Jobs, Steven Levy, Tacoma Narrows Bridge, the scientific method, The Wisdom of Crowds, time value of money, too big to fail, transaction costs, Turing machine, Upton Sinclair, value at risk, Vernor Vinge, yield curve, Yogi Berra, your tax dollars at work

There are many civilian examples of bad engineering, ranging from simple miscalculation to astounding idiocy. Some had relatively minor consequences, as in the photogenic 1895 train disaster at Montparnasse Station, Paris, seen in Figure 12.2. Figure 12.2 The 1895 train disaster at Montparnasse Station: If only the other errors discussed in this chapter could have been avoided by a heavier foot on the brake. Source:Wikimedia. Shooting the Moon 289 The collapse of the first Tacoma Narrows Bridge in November 1940 (depicted in Figure 12.3) just four months after it opened is an example of the kind of bad modeling we have seen lately in asset pricing models.11 The mathematical model used to design the bridge, like those used to price mortgage-backed CDOs, was fatally flawed. What worked in light breezes (normal housing lending) failed spectacularly in a storm (no-income, no-job, no-assets undocumented lending).

Many involve management’s head-in-the-sand desire to avoid the expense of better safety. Parallels are found in many stories related by Wall Street quantitative risk analysts of their interactions with their bosses in 2007 and 2008. This kind of screw-up remains distressingly common.12 A multilevel Kansas City Hyatt Regency hotel walkway collapsed in 1981, killing Figure 12.3 Still from a video of the collapse of the Tacoma Narrows Bridge, which has been dear to engineering and physics students ever since. This is another still that really needs to be seen as part of a movie. Source:Wikimedia. 290 Nerds on Wall Str eet Figure 12.4 The Hindenberg, a potentially avoidable disaster. Our financial meltdown was avoidable too. Source:Wikimedia. 114 people. The walkways on floors two, three, and four of the hotel were supported by multiple steel rods tied end to end, instead of a single long rod passing through all three levels.

pages: 252 words: 73,131

The Inner Lives of Markets: How People Shape Them—And They Shape Us by Tim Sullivan

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Airbnb, airport security, Al Roth, Alvin Roth, Andrei Shleifer, attribution theory, autonomous vehicles, barriers to entry, Brownian motion, centralized clearinghouse, Chuck Templeton: OpenTable, clean water, conceptual framework, constrained optimization, continuous double auction, creative destruction, deferred acceptance, Donald Trump, Edward Glaeser, experimental subject, first-price auction, framing effect, frictionless, fundamental attribution error, George Akerlof, Goldman Sachs: Vampire Squid, Gunnar Myrdal, helicopter parent, information asymmetry, Internet of things, invisible hand, Isaac Newton, iterative process, Jean Tirole, Jeff Bezos, Johann Wolfgang von Goethe, John Nash: game theory, John von Neumann, Joseph Schumpeter, Kenneth Arrow, late fees, linear programming, Lyft, market clearing, market design, market friction, medical residency, multi-sided market, mutually assured destruction, Nash equilibrium, Occupy movement, Pareto efficiency, Paul Samuelson, Peter Thiel, pets.com, pez dispenser, pre–internet, price mechanism, price stability, prisoner's dilemma, profit motive, proxy bid, RAND corporation, ride hailing / ride sharing, Robert Shiller, Robert Shiller, Ronald Coase, school choice, school vouchers, sealed-bid auction, second-price auction, second-price sealed-bid, sharing economy, Silicon Valley, spectrum auction, Steve Jobs, Tacoma Narrows Bridge, technoutopianism, telemarketer, The Market for Lemons, The Wisdom of Crowds, Thomas Malthus, Thorstein Veblen, trade route, transaction costs, two-sided market, uranium enrichment, Vickrey auction, Vilfredo Pareto, winner-take-all economy

Things like Euler’s buckling equation, which provides the maximum axial load that a long, slender, ideal column can carry before it crumples, are important background knowledge for bridge builders to be. But the theoretical constructs involving “ideal” columns will take you only so far. A bridge that stands in theory may, in practice, sink into the riverbed or ripple with wave-like undulations when the wind blows just so. (If you want to see a dramatic example, go to YouTube and watch the Tacoma Narrows Bridge collapse.) Every bridge presents its own unique design challenges—the soil, the way the river flows, the weather, the wear and tear of cars and trucks speeding to and fro. You start with Isaac Newton and Leonhard Euler, but had better take into account the complexities of each situation even if it doesn’t allow you to derive a simple “final answer.” That makes bridge engineering a messier process, involving extended computer simulations, site visits to scope out the river-bank, analysis of soil samples, and stress testing scale models in a wind tunnel.