"Why had she always felt that joyous sense of confidence when looking at machines?"

"[Dagny] felt the sweep of an emotion which she could not contain, as of something bursting upward. She turned to the door of the [diesel combustion engine], she threw it open to a screaming jet of sound and escaped into the pounding of the [locomotive]’s heart. . . . 

    "Why had she always felt that joyous sense of confidence when looking at machines?—she thought. In these giant shapes, two aspects pertaining to the inhuman were radiantly absent: the causeless and the purposeless. Every part of the motors was an embodied answer to ‘Why?’ and ‘What for?’—like the steps of a life-course chosen by the sort of mind she worshipped. The motors were a moral code cast in steel. 

    "They are alive, she thought, but their soul operates them by remote control. Their soul is in every man who has the capacity to equal this achievement.”

          ~ Ayn Rand, from her novel Atlas Shrugged

[Hat tip Stephen Boydstun]

.

Machine of the Day: The ‘zipper truck’ that makes building tunnels a breeze!

 

This beauty makes cut-and-cover tunneling a breeze!

[Hat tip Jeffrey Perren]

Machine of the day:

Capital leverages human effort. Capital in the form of modern machinery can make one person far more productive today than a hundred, or even a thousand might have been in the past. (Making a thousand of us … well, you work it out…)

Take this logging machine by Ponsse North America …

How cool is that!

PS: There are over 3 trillion trees on Earth, 7 1/2 times more than previously expected; and where property rights are strongest most trees harvested for commercial use today are re-planted, making plantation forestry an actual renewable resource. What’s more, rapid growth of plantation timber and rapid logging of it could, between them, rapidly lower the worldwide price of housing …

[Hat tip Betty Brock-Porter & Michael Adams]

What science makes possible

Science and technology making human life greater: watch a man see for the first time in 33 years, thanks to his new bionic eye.

[Hat tip Julian D.]

EARTHQUAKE ENGINEERING OF THE DAY: Early-warning system

Astonishingly, an early-warning system at UC Berkeley was able to give a 10-second alert before the Napa earthquake struck this morning.

That might not sound like much, but that is precisely 10 seconds more warning of destruction than anyone has been able to enjoy before. Even better…

California is working to complete a statewide system, which could be unveiled in the next few years.

Once fully developed, the system could give downtown Los Angeles 40 to 50 seconds of warning that the “Big One” was headed from the San Andreas fault, giving time for elevators to stop at the next floor and open up, firefighters to open up garage doors, high-speed trains to slow down to avoid derailment and surgeons to take the scalpel out of a patient.

It’s not magic.  It can’t look forward in time or anything.

The system works because while earthquakes travel at the speed of sound, sensors that initially detect the shaking near the epicenter of a quake can send a message faster -- at the speed of light -- to warn residents farther away that the quake is coming… “even a few seconds of warning will allow people to seek cover…”

So, if you’re at the epicentre you’re still stuffed. But anywhere further afield, and this could save your life.

Machinery of the day: Waterview spoil

Here’s the latest video showing the construction of the Waterview tunnel, this time highlighting the removal of spoil from the tunnel face. An almost wholly mechanised process, at the rate of one trailer truck load every ten minutes.

It reminded me of the observation that capital goods – machines and the like – all that good stuff that Thomas Piketty and his crowd think are unnecessary and irrelevant to production – are in fact tools by which human effort is vastly leveraged,, making work like this possible. (Not just more roundabout production, but production that wouldn’t be possible otherwise.)

Transport Blog has more of the tunnel story.

British motor engineering is dead?

As a driver of a classic British car myself, I too have subscribed to the view that British motor engineering is long dead. Not so, said this season’s final episode of Top Gear –apparently those feet in modern times still drive upon England’s mountains green:

Building revolution: contour crafting

There are several revolutions in building on the horizon*.

Here’s one:

[Hat tip Julian P.]

* * * * *

* Presuming any of them can sneak through the bureaucracy…

Earthquake engineering is not an exact science

AFTER THE REPORT ON the collapse of the CTV building, everyone now wants to hang the builder and designers.

“Someone is incompetent!” Is the cry. “Someone must be to blame!” “There's criminal negligence going on there somewhere…."

No. Not necessarily. None of that follows necessarily from the report.

It seems on the face of it that people are not so much blaming people for not being competent, but for not being omniscient.

Because I think the problem is not one of negligence but one of the nature of knowledge.

COMPARING THE POOR STATE of Christchurch’s heritage buildings after the earthquake with most of its modern buildings is enough to tell you that earthquake engineering has improved rapidly over the last century. That knowledge has increased and will continue to increase.

It is a heroic tale. From a position of almost complete ignorance one-hundred years ago, engineers acquired increasing understanding and ingenuity in protecting buildings and the people in them--with new and revolutionary systems introduced in recent decades such as K-Braced Frames, Base Isolation and Ductile Design—saving literally millions of lives around the world, and hundreds of thousands in Christchurch.

Where just seventy years ago in First World countries like ours people still died en masse in earthquakes like the Napier disaster, today the earth can shake well beyond what even modern building were designed to handle—as it did in Christchurch on February 22nd—and ninety-nine per cent are still able to survive heroically and allow people to get out safely.

That we are talking about just two that didn’t (this one and Pyne Gould) is a tragedy on a massive scale. Let’s not downplay that. But that we are talking about just one that didn’t is a testament to the engineering in all the buildings that did. The engineers responsible used all the the knowledge acquired in recent years to design them; knowledge that will increase in future years.  But as the knowledge continues to increase, some of the methods used today will also shown to be wrong and less than adequate by engineers fifty years from now (as they undoubtedly will).

That  will not make today’s engineers negligent. They will simply be revealed as less than omniscient.

Just like every other human being.

SO EARTHQUAKE ENGINEERING IS still an inexact science, with new understanding emerging  after every earthquake that helps engineers understand more for the next one. After this one, for example, we’ve learned that the ground can move in very different ways than buildings have been designed for. It’s not necessarily a matter of criminal negligence, then—it’s more the nature of knowledge and how it improves, is tested and expands.

Reading summaries of the report with that in mind, when you boil it down it seems that in the early eighties we knew less about designing buildings to resist earthquakes than we do now.  Which is nothing to blame anyone for. And (perhaps) that too little was done to upgrade buildings like CTV’s that were designed before the modern era of seismic design.  Which is where any blame, if it’s deserved, probably lies.

This building for example was designed with its bracing walls disposed asymmetrically. But, for whatever reason, the importance of symmetrical bracing was less well understood then.

The building’s floors appear to have “pancaked,” which is what happens when columns collapse and one “soft storey” after another collapses on the one beneath. But back in the early eighties, engineering wisdom was still dictating that beams be designed stronger than columns—a situation eventually recognised as causing columns to fail before beams, leading inexorably to the pancake problem.

The columns are described as “brittle”—which is say they were not ductile—on which were imposed extra loadings from the increased twisting of the building. But the building was designed before the importance of Ductile Design was fully understood. 

As the engineers responsible for designing CTV, Alan Reay Consultants, said in a prepared statement yesterday:

We need to remember that the [design methods] of the day, when the building was designed and constructed, were not intended to withstand the magnitude and type of earthquake ... experienced on February 22.

They’re quite right.

Things have changed since then—but to call the engineers of the time negligent because they knew less than they we do now, and will know in the future, is to blame human beings for not being omniscient.

Which is not anything you can blame engineers for.

MACHINE OF THE DAY: The largest floating offshore facility in the world

Shell’s 488m long floating liquefied natural gas facility, the first ever of its kind, will allow oil producers to open up new natural gas fields at sea currently considered to costly or difficult to develop.

It’s “a game changer.”

Technology. It’s what keeps us alive.

GUEST POST: Watt a Genius

The first guest post here from our newly-minted (ir)regular columnist who we’ve dubbed, for reasons that will become apparent over subsequent weeks, InsideTheWall.

The release of the Atlas Shrugged: Part 1 movie found me reading the perfect accompanying book.

Called Great Inventors & Their Inventions, the first biographical account is of James Watt, the man who turned Newcomen's early attempts at a steam engine (at the time known as the Fire Engine) into a working, reliable and powerful engine that we all heard about in school.

Not only does the story tell of the money he spent and borrowed, the extraordinary graft, the years of trials and failures–it also tells a story of applied genius, of one man against the mob (a story which of course we didn't hear in school) and how he overcame all the hurdles to achieve eventual recognition and success, bringing a new thing into existence that transformed men’s lives.

So here's a long story short. The story began with him designing his engine simply to pump water out of mines. But he quickly saw there were hundreds more applications for it—particularly in mills  grinding corn and wheat which at that time were powered by either wind or water, making them either unreliable or unable to be located away from a water course.

The working people of these mills didn’t see the increased production of cheaper food that he saw however; they saw only a danger to their incomes, and began to protest at the installation of Watt’s new engines, often quite violently. Not for them the labour-saving utility of such a powerful and never-get-tired contraption, one that would eventually make everyone richer.

“It seems [wrote Watt at the time] these people are determined to be masters of us. To put a stop to fire-engine mills, because they come in competition with water mills, would be as absurd as to put a stop to canals, because they interfere with those who carry things by wagon. The argument that men are deprived of a work would put a stop to the use of all machines whereby labour is saved. Carry out this argument, and we must do away with water mills themselves, and go back again to grinding corn by hand labour.”

So strong were the feelings against Watt's machine that when he and his business partner built a sixty thousand dollar (do your own conversion into pounds and add inflation) working mill of their own it was deliberately burnt to the ground.

But all was not lost, the working mill lasted long enough that it created interest from industrialists from Britain to France, from Italy to America. The Luddites lost! Watt won. And so did we.

So successful did his engine prove to be that opposition changed from destroying his products to stealing them. Unscrupulous mine owners refused to pay for the machines that had raised their production. And perfidious competitors stole and used his patents unpaid, and attempted to have his ownership of them stripped—asking Parliament to do down the very man who had given them their chance at (unearned) piles of money.

"We are in the state of the old Roman [wrote Watt] who was found guilty of raising better crops than his neighbours, and was ordered to bring before the assembly of the people his instruments of husbandry, and tell them of his arts. He complied, and when he had done, said, 'These, O Romans, are the instruments of our art, but I cannot bring into the forum the labours, the sweats, the watchings, the anxieties, the cares which produce the crops.' So everyone sees the reward which we may yet probably receive from our labours; but few consider the price we have paid for that reward, which is by no means certain."

Eventually, however, the great man received the justice, and the honours, he deserved. And here, to show the esteem in which his country finally held him, is the inscription from the monument dedicated to him in Westminster Abbey:

“Not to perpetuate a name which must endure while the peaceful arts flourish, but to shew that mankind have learned to know those who best deserve their gratitude. The King, His Ministers, and many of the Nobles and Commoners of the Realm raised this monument to JAMES WATT who, directing the force of an original Genius, early exercised in philosophic research, to the improvement of the Steam Engine, enlarged the resources of his Country, increased the power of Man, and rose to an eminent place among the most illustrious followers of science and the real benefactors of the World.

Can you imagine any businessman having this said of him now?

Lifting man to the heavens…

This morning was the Space Shuttle Discovery touched down for the last time [VIDEO], the longest-serving and most-travelled winged spaceship ever. 

There are problems with government space exploration:

As the grandest of man's technological advancements, requires the kind of bold innovation possible only to minds left free to pursue the best of their creative thinking and judgment. Yet, by funding the space program through taxation, we necessarily place it at the mercy of bureaucratic whim. The results are written all over the past twenty years of NASA's history: the space program is a political animal, marked by shifting, inconsistent, and ill-defined goals.

And yet, we have seen a great human achievement.

It was other vehicles that first made space a place that man could visit. It was these Shuttles, allowing an easy return journey, that allowed men and women to begin the process by which man first began making a home there.

As the workhorse in that fleet retires, it’s a good time to celebrate that.

PS: the source of this picture is the blog Temple of the Human Spirit.
If celebrating human achievement is your passion, you should give it a regular visit.

Don’t get “tough” on Christchurch building standards. Get smart.

If I had a dollar for every time I’ve heard someone say we need “tighter” building standards, or that New Zealand’s “tight” building standards saved lives in Christchurch, I’d be, well, I’d be richer than I am now.

Many people seem to labour under the illusion that building standards are a gift of government. That all government needs to do is mandate tough standards for builders and designers to follow, and the world would be a happier place. 

This is really a child’s view of reality.  It’s as if there’s a bag of special tricks that everyone knows about, and nasty builders and designers hope to hoodwink the people who pay them by pretending not to know it’s there.

Off the top of my head, there’s at least three things wrong with this.

First of all, it’s not simply a matter of “tougher” or “softer” regulations. That’s a complete false dichotomy. Good ways to build are neither tough nor soft, they’re intelligent. They’re methods devised by smart people in every generation to do what needs to be done with the material at hand—and many of the smartest building methods use the least material: and the material that is used is used intelligently.

Second, it ignores most of human history. This might surprise some people, especially the paid lap-bloggers at the Sub-Standard, but for most of human history there were really no building codes at all. And the best of what was built over most of that history can be seen on my fridge, because every time friends go overseas they send me postcards to taunt me with where they’ve been. Bastards.

Now sure, the Code of Hammurabi certainly goes back to ancient times—and for those who don’t know this was a rule in ancient Babylon that said if your building falls on someone else’s head, then Hammurabi will cut off yours.  But while tough, this was hardly a prescriptive Building Code. It still relied on some smart person to work out how to build so everyone’s head (especially the smart person’s) was safe.

Which brings us to our third and most important point. The techniques for building so things don’t fall down don’t pre-exist; they have to be created.

Making buildings so they don’t fall down is a science. Some smart person had to look at the problems making other buildings fail, and devise a real-life solution to make sure his building doesn’t. (This is how we got everything from pointed arches to flying buttresses to hypar shells to K-braced frames to slotted concrete seismic shear walls—indeed, this is how we got everything that goes into making every modern building. They represent embodied intelligence. The techniques weren’t simply sitting around waiting for governments to make them compulsory.)

The residue of what these smart people do does might eventually end up in a building code somewhere—if the building code itself hasn’t been written to make these new techniques impossible. (You see one of the problems with a “tough” building code?)  But it sure as hell didn’t start there.

Now, one of the things seismic engineers do especially well is to devise new solutions to the problems that have made other buildings fail—because as most of you will by now have discovered by reading around, the way the earth acts on a building in an earthquake is not always easy to predict.

The Christchurch earthquake is a perfect case in point. 

Up to now, buildings have largely been designed to take gravity loads (which act downwards) and wind and earthquake loads  (which after decades of analysis have always been assumed to act sideways, as you can  see in these Shake Tables use to test building models.)

But this last big earthquake in Christchurch was different. The ground didn’t act that way—and not just because some it liquefied under some of the buildings.

Instead in Christchurch the ground exerted a big sideways force (about as big as the force of gravity, only sideways), and also a big upward force as well. Big enough to be twice as big as the downward gravity force.  Essentially the earthquake threw buildings up in the air (severing some piled foundations in the process) and then let the ground catch them.

And Christchurch’s buildings weren’t designed for that. Nor are any buildings anywhere anywhere else.

This is why a lot of seismic engineers like to keep a fully loaded suitcase by the bed.  Every time there’s an earthquake anywhere in the world, the world’s top seismic engineers head to the airports in droves to see what happened this time, and how the latest theories about seismic engineering have held up.  This is one reason that makes them top engineers.

In Christchurch what these engineers will  surely discover, despite the braying about modernbulding codes saving people’s lives, that both modern buildings and heritage buildings have failed alike. Provincial Chambers, CTV, Pyne Gould, Park Royal, Gallery Apartments, the new council building, Cashel St Bakery building, Old Arts Building, virtually every church in the Cathedral City … all now have either failed or have problems.  Some modern buildings collapsed in surprising ways. Many failed while still saving the folk within. And many heritage buildings lost their outer brick skins, while still keeping roofs, partitions and structural frames intact.

Many of these building were even built (or renovated)  to modern building codes.

They still failed.

Which tells us once again if we’re open about it that it’s not a case of simply being “tough” or “soft” about how people build. If it was that easy to know what to do we wouldn’t have seen over the last few months the government’s and council’s pendulum swinging from insisting before the last earthquake that no heritage building will be demolished (“You will not touch your heritage buildings,” an emotional councillor Sue Wells harangued building owners before the last earthquake) to insisting this week that every heritage building must go.(''What we've got in the CBD is 500-plus [heritage] buildings that will need to be demolished,'' Gerry Brownlee told those building’s owners through the media.)

This is the way governments act when they get “tough.” Without a clue.

The point is not to act tough, but smart.

The real point, perhaps, is to let those who know best do their best.  And people like Gerry Brownlee and Sue Wells are very much not those people.

It’s a matter of devising a method by which those who actually do know the field of risk and structures and construction between them, by voluntary agreement, produce smart intelligent ways to allow people to build in a smart and intelligent way---in a way that doesn’t require ratepayers and taxpayers to assume financial responsibility.

One thing Gerry Brownlee could do if he was smart enugh is to get started on enacting such a proposal that is already sitting around all ready to go in the Department of Building and Housing. The proposal would essentially allow standards to bet set voluntarily by those who benefit most from high standards, and requires risk to sit with insurers, who do that best.

The discussion document tucked away in the DBH – the Building Act Review – … hints … in short, [that] compliance and regulation would be taken off local government and handed to the building industry. Insurers would indemnify the builder and if a leaky home popped up, the insurer would deal with the homeowner and fix the problem.

Essentially it’s not Sue Wells and her employees that builders and designers would have to convince, with all the risk that implies for ratepayers, but their insurers. This should save everyone in time, lives .. and money.

Councils would not be collecting building permit and inspection fees – the average $15,000 per new house spent in this way would more than cover the cost of indemnity.
    If the developer or builder went bust, the insurer would find another they could trust and fix the problem. The insurer would decide which builders – and developers – to trust. All the council would do would be to identify where the house would go, how high and wide it would be, and what services would hook up to it.
    Looking at the case of [the failed subdivision of] Bexley [for example, where the council allowed the subdivision and home building to proceed on the assumption that designed engineering solutions could compensate for the instability and lack of support of the ground], the indemnifier might want something better than the assurance of an ‘engineering solution’ for the ground problems.
    If the insurer refused to cover the subdivision, the houses wouldn’t be built there.
    This approach would oblige the industry to get out of nappies. It would take licensing builders away from the DBH and cut many of the DBH tentacles gripping and, in some cases, choking the industry. The DBH [or, indeed, whomever the various insurers chose to specify as their variously chosen authorities] would deliver a building code everyone could use and which would ensure safe and functional buildings. That would be the end of its responsibility on behalf of the taxpayer.
    This approach would also require the building industry to face its skill issues. This could be as simple as having labourers capable of following manufacturers’ directions properly when fitting windows, flashings, cladding systems and so on. This was a key factor in the leaky home scenario.
    Insurers would also bring architects in line, with design constraints and manufacturers guidelines. If a homeowner wanted the architect to move beyond certain parameters, it would be the insurer the architect would have to convince, because that’s who would carry the cost if the design ran into problems.
    The phased changes in the Building Amendment Act 2009 are a watered-down version of the changes needed – changes that, ultimately, would take the taxpayer out of the picture if something went pear-shaped, or, as at Bexley [and now the rest of Christchurch], turned to custard.

This makes infinitely more sense than anything I’ve heard in recent days from people talking about “tougher” building standards.

Don’t get tough. Get smart.

And if you need to, get started on getting smart in an Enterprise Zone in Christchurch.

MACHINE OF THE DAY (RE-POST): Inflatable Jacks—the perfect thing for earthquake rescue

I first posted this in January last year after the Haiti earthquake. With the fanning out around Christchurch today of specialist urban search-and-rescue crews, we might see some of these beauties being used to save human lives.

Our ‘machine of the day’ today has to be the amazing rescue air bag. An inflatable jack.  So simple, yet such an effective way to rescue people trapped under wrecked cars or buried under tons of rubble.

Just like they are in Haiti (where the only good news today is that their tax office now lies in ruins).

Inflatable jacks are especially effective when a building’s floors have “pancaked”—i.e., when the columns have collapsed in a quake letting the floors fall, sickeningly, in sequence, one on top of another.  With people trapped in between.

Just like that pile of rubble on the right that used to be a six-storey building.

But you’re no less trapped under the collapsed two-storey below.

Instead of using your regular hydraulic or scissors jack to lift the rubble (with their point-loads creating problems and their inherent instability) or the agony of carefully (and slowly) hacking through layers of rubble with pick and hammer, these inflatable babies can be slid underneath and inside the layers and easily inflated: safely spreading the load as they lift so they don’t  disturb the debris any father or set up dangerous new load paths to endanger other folk who are trapped. 

You can lift gently and simply, with the lift always controlled and stable—even during aftershocks.  The bag is always its own “safety mat.”

Brilliant!  The mind’s ingenuity applied to the rescue of human life.

I hope there are truck loads of ‘em on their way to Haiti Christchurch right now.

NB: I can’t finds any clips showing the inflatable jacks in use in earthquake rescues.  I guess everybody’s always too busy.  But here’s a few clips showing ‘the power of the bag’ for lifting vehicles.  You’ll have to extrapolate.

As you see, they come in all sizes, large and small. And they can be used so delicately, they’re also just the thing for moving your Polaris rocket:

RELATED POSTS:

• EARTHQUAKE ENGINEERING OF THE DAY: The K-Braced Frame
• EARTHQUAKE ENGINEERING OF THE DAY:  Base Isolation
• EARTHQUAKE ENGINEERING OF THE DAY: Ductile Design
• Something Smells in the Christchurch Civic Centre

EARTHQUAKE ENGINEERING OF THE DAY: Ductile Design [updated]

“Ductile, a., malleable, not brittle; capable of being moulded; pliant, tractable, yielding to persuasion or advice…”

Most buildings don’t use the sort of fancy nancy systems I’ve already described like base isolation or K-braced frames. They use something more subtle and much less expensive called “ductile design”—not making buildings strong so much as making them flexible.

You might think that answer for better earthquake protection is to make buildings stronger and more rigid.  But this is no more true for a building in an earthquake than it is for a car in a crash.  The best kind of car to drive into a brick wall is not one that’s strong and rigid, but one that crumples in a way that protects the occupants and absorbs the energy of the crash. And so it is with a building: no building could fight the power of the earth by staying perfectly rigid—such strength acts like a lightning rod to the earth’s forces, inviting your building to be shaken to pieces  The best structures in which to ride out an earthquake are designed not to stand up rigidly but to absorb the earthquake’s energy by yielding gently while the earth moves—in the same way a willow tree moves with the wind instead of standing up to it rigidly.

People speak of tall buildings swaying during a high wind.  Let me assure you, tall buildings sway just as much (or more) during an earthquake, and they’re designed to.  Leastways, modern buildings are.  And as they sway, the frame of the building is absorbing the violence of that horizontal motion imposed by either wind or earthquake, and transmitting it evenly throughout the joints of the building.

It’s those joints between columns and beams where the ductility of a building’s structure is really designed in. Imagine a chest of drawers with all the drawers out and the back taken off.  That’s something like the typical structural frame of your tall building—except in a tall building the joints where uprights meet horizontals are designed to take the strain. Push your chest of drawers from the side and at the top while keeping its feet on the ground, and you’ll hear its joints creaking as they (hopefully) take the strain of your shove. In a building frame that’s been designed with ductility, those joints won’t creak (not if designers and builders have been doing their job) but will instead remain elastic as the building sways gently from side to side.

(Now you understand that a modern building is designed to move during an earthquake, you’ll be less frightened when you feel it moving.)

Naturally, the material of which your building frame is designed makes a difference to how it performs. Ductile is better than brittle. 

Steel is a naturally ductile material—at least until successive shakes turn it plastic—so is a popular material in an earthquake zone. Concrete reinforced with steel can be made ductile with careful detailing, especially at those joints.  Timber itself is more brittle than ductile, but the things that hold it together (like nails, nails plates, steel connectors etc.) give a timber frame its ductility.

Brick walls, however are not ductile (as you can see in the video below). Not ductile at all. They can be tied back to things that are, but since the brick walls and steel frames to which they’re tied move at different rates, this is not as easy as it sounds.  This explains why the Christchurch earthquake was felt so severely by the plaster facades of Christchurch’s heritage buildings, and the brick walls on which those facades were installed.

There are obviously some subtleties involved there that it took some time for even experienced earthquake engineers to discover and work out.

They discovered it was more economical not to design a typical workaday building to be completely damage-free after a quake, but primarily to ensure that people inside will be safe when the ground is moving, and when the shaking does finally stop that they can get out safely—and the building itself can be easily repaired. That If the structural frame is allowed to sway, then you need to detail walls and windows to fit inside these swaying frames so that the movement of the structure doesn’t damage these secondary elements. 

And they discovered that if a ductile building is to remain standing then its beams need to be made to fail before its columns—and that the “plastic hinges” formed as the beams do fail actually help to absorb the earthquake’s energy, protecting the rest of the building. (It was this insight that inspired the plastic “hinges” of the K-braced frames.)

Good:

Not good: Because you really want to avoid having a “soft storey.”

Ductile design.  One of engineering’s primary means of ensuring our buildings can protect us while resisting the worst the earth can throw at them.

UPDATE: Watch this great video:

In seismic design, designing a system to be stronger than the earthquake was typically the approach: “the stronger we make it, the safer we are.” That approach has been proved to be wrong…
Dr Stefano Pampanin from the University of Canterbury explains how the ‘smarter’ idea of ductile design originated at the University in the 1960s and is currently under further developments and refinements. Making buildings stronger is not the answer for earthquake protection.

EARTHQUAKE ENGINEERING OF THE DAY: Base isolation

It's surely occurred to everyone at some stage during an earthquake that when the ground is moving underneath you, the best place to be would be well away from the ground.

That thought also occurred to a very smart New Zealand engineer back in the 1970s, Dr Bill Robinson (right), and in 1976 he developed a system to do it that is now implemented in around 3,000 buildings and bridges worldwide—including, unfortunately, Wellington’s parliament buildings (simultaneously protecting its inhabitants, and making the idea of a Wellington earthquake far less attractive).

Robinson’s basic system is essentially a lead-rubber bearing (left) placed between the ground and a buildings foundations either during original construction (as with Te Papa) or afterwards (as with the parliament buildings) to reduce the force exerted on the building by the ground’s movement.  The outer rubber “sandwich” gives the bearing flexibility, while the lead damps down the movement and absorbs the earthquake’s kinetic energy, turning it into heat. 

 Working together in the same way a car’s springs and dampers do, they reduced the earthquake force in buildings and bridges in both the Northridge and Kobe quakes to about one-fifth the seismic force that un un-isolated building or bridge would suffer—allowing bridges, hospitals and buildings necessary after a major shake to to ride out the earthquake undamaged, even while all around them is a sea of destruction.

You can see how effective it is in these videos of building models on a “shake table” set up to compare buildings that have been base-isolated and those which haven’t.  It’s a pretty persuasive demonstration.

Since Robinson’s invention of the lead-rubber bearing, many other systems have been developed following the same principle—including base-isolated tables designed to protect fragile objects during a quake. And there’s even one Canterbury economist who’s protecting his child right now with what he calls “a Gerry-rigged earthquake base isolation unit” for his 4 month old, which has successfully kept Eric Crampton’s youngster safe through two aftershocks.

There’s a neat video here at the Science Learning site where Robinson explains the life-saving concept of his lead-rubber bearing and how he came up with it—and there’s plenty more links there to take you further…

Earthquake Engineering of the Day: The K-Braced Frame

New Zealand engineers are among the world’s leaders when it comes to earthquake engineering—everyone in Christchurch right now might like to pause at some stage and say a silent “Thank you” to the men and women who designed the structural systems that kept them safe through an earthquake of the same strength that killed hundreds of thousands of poor souls in Haiti last January.

So I thought over the next few days, by way of thank you, I’d start showing you just a few of the ingenious creations of seismic engineers that help keep people safe, beginning by re-posting a system I talked about a few months ago, the “K-braced frame.”

There are people who say engineers aren’t creative. Not true. Just look at this cunning rearrangement of traditional structural elements that makes tall buildings less expensive to build for earthquakes, safer in an earthquake, and more likely to be useable afterwards.

You might have seen ‘K-braced frames’ on the outside of buildings all over the world, and you’ll certainly have spotted them if you’ve ever taken a decent look at Auckland Hospital (right), which is a variant on the theme.

And it’s a pretty good theme. You see, the main aim in earthquake design is to make sure people can get out safely – which means to avoid the building collapsing.  The K-brace (and its cousins the V-brace and the D-brace) do that and much more: they also make it easy to repair the building after an earthquake so that it can get straight back into action – which is pretty important for a major hospital.

The two key elements of these bracing beauties are, 1) the “triangulation” of the structural members, and 2) that little piece labelled ‘e’ on the drawings above. ‘e’ is actually called a “link”—a “sacrificial link.”

The seismic engineer uses the nature of both geometry and earthquakes to make your tall building safer. And how he does it is so elegantly simple it’s almost laughable. He does it by making that little link act like the fuse in your fusebox.

You see, earthquakes tend to shake buildings from side to side, the result of which which you can see happening in that diagram on the right.  And since triangulated structures tend to be rigid, when the building moves a little to one side the geometry of the K-brace means that the link moves a lot.

So as the building moves from side to side in a quake (and some quakes can go for a minute or more, meaning lots of shimmying) that link is working up and down and up and down so many times it eventually turns the heavy section steel into chewing gum. Into plastic. And and in the process of being deformed, it’s absorbing much of the earthquake’s energy that would otherwise have gone into destroying the parts of the building that hold it up.

But as long as our sacrificial link is turning to plastic, then our beams and columns aren’t. That’s the beauty of the system. Let the link die, and use it to absorb and save the building and its occupants—and afterwards, by way of repair, all that’s often needed is to take out the deformed links and replace them with new ones.

Now how’s that for ingenious.  Taking the same materials normally used in a building frame, and placing them in an arrangement designed to better combat earthquakes. And since creativity consists of “the power to rearrange the combinations of natural elements” then this sort of ingenuity is the very acme of creativity, and much more interesting than most of the stuff that flies under that flag.

MACHINE OF THE DAY: The household robot

Yes, it’s a specially designed machine just for one simple household task; yes, this video is sped up fifty times to make viewing easier; yes, it would cost more than a simple servant to do the same job; yes to all of that . . . but for a machine in 2010 to accomplish this task with objects of different dimension it hasn’t seen before, and which flap around so, suggests that machines not so many years from now will be performing all sorts of labour-saving tasks we’d rather not be doing ourselves.

Which promises to transform life in the Twenty-First Century.

And that’s pretty cool.

So thank the nice people at the UC Berkeley Robotics Lab who designed and built it. [Hat tip Willy S.]

MACHINE OF THE DAY: Inflatable jacks—perfect for earthquake rescue

Our ‘machine of the day’ today has to be the amazing rescue air bag. An inflatable jack.  So simple, yet such an effective way to rescue people trapped under wrecked cars or buried under tons of rubble.

Just like they are in Haiti (where the only good news today is that their tax office now lies in ruins).

It’s especially effective if a building’s floors have “pancaked”--when the columns collapse in a quake, and the floors fall, sickeningly, in sequence, one on top of another.  With people trapped in between. Just like that pile of rubble on the right that used to be a six-storey building.

But you’re no less trapped under the one below.

 

Instead of using your regular hydraulic or scissors jack to lift the rubble (with their point-loads and inherent instability0 or the agony of hacking through layers rubble with pick and hammer, these inflatable babies can be slid underneath and inside the layers and easily inflated: safely spreading the load as they lift so they don’t  disturb the debris any father, or set up dangerous new load paths to endanger other folk who are trapped. 

You can lift gently, simply, and always be controlled and stable—even during aftershocks.  The bag is always its own “safety mat.”

Brilliant!  The mind’s ingenuity applied to the rescue of human life.

I hope there are truck loads of ‘em on their way to Haiti right now.

NB: I can’t finds any clips showing the inflatable jacks in use in earthquake rescues.  I guess everybody’s always too busy.  But here’s a few clips showing ‘the power of the bag’ for lifting vehicles.  You’ll have to extrapolate.

 

As you see, they come in all sizes, large and small. And they can be used so delicately, they’re just the thing for moving your Polaris rocket:

Fine ‘Machinery’ of the Day: The K-Braced Frame

There are people who say engineers aren’t creative. Not true.  Just look at this cunning rearrangement of structural elements that makes tall buildings less expensive to build for earthquakes, safer in an earthquake, and more likely to be useable afterwards.

You might have seen ‘K-braced frames’ on the outside of buildings all over the world, and you’ll certainly have spotted them if you’ve ever taken a decent look at Auckland Hospital (right), which is a variant on the theme.

And it’s a pretty good theme. You see, the main aim in earthquake design is to make sure people can get out safely – which means to avoid the building collapsing.  The K-brace (and its cousins the V-brace and the D-brace) do that and much more: they also make it easy to repair the building after an earthquake so that it can get straight back into action – which is pretty important for a major hospital.

The two key elements of these bracing beauties are the “triangulation,” and that little piece labelled ‘e’ on the drawings above. ‘e’ is actually called a “link.” A “sacrificial link.”

The seismic engineer uses the nature of both geometry and earthquakes to make your tall building safer. And how he does it is so elegantly simple it’s almost laughable. He does it by making that link act like the fuse in your fusebox.

You see, earthquakes tend to shake buildings from side to side, which you can see happening in that diagram on the right.  And since triangulated structures tend to be rigid, when the building moves a little to one side the geometry of the K-brace means that the link moves a lot.

So as the building moves from side to side in a quake (and some quakes can go for a minute or more, meaning lots of shimmying) that link is working up and down and up and down so many times it eventually turns the heavy section steel into chewing gum. Into plastic.

But as long as our sacrificial link is turning to plastic, then our beams and columns aren’t. That’s the beauty of the system. Let the link die, and save the building and its occupants.

And there are two added treats:

1. the energy needed to turn the link into plastic helps absorb and dissipate the energy of the quake; and
2. when the earthquake’s over, the most major repair you might need to make to your building is to cut out the link and put a new one in.

Now how’s that for elegant.  And creative -- indeed if creativity consists of “the power to rearrange the combinations of natural elements,” then this is the very acme of creativity, and much more interesting than most of the stuff that flies under that flag.