The CAD Insider

How Much Does Your Building Weigh?

Architects struggling to get in touch with their inner environmentalist may need to look no further than the weight of their buildings.

I'm heading back from New York City, after an Imaginit-hosted event on sustainability in architecture. I'm composing this on an airplane. Airlines are slavishly weight conscious (a trait not shared by my 300 lb neighbor who is very much in my personal space). The building industry may do well to copy the airlines' lead. After all, less bulding materials equal less trees being cut for lumber, less earth ripped up to make concrete and gather ore, and less energy used to create steel.

Duh, you say? Yeah, I know, it seems obvious. Yet, weight optimization -- a requirement for just about every part that flies --is a rarity for things that sit on the ground. While a slender skywalk may have a FEA done (after all who wants another Kansas City hotel disaster?), most build structures seem incredibly overdesigned -- and weighty. Concrete is poured by the truckload and massive I-beams are in place to support circus elephant acts on every floor.

A ThorntonTomasetti-designed stadium (top), which relies on structural members in tension, may be an order of magnitude less weighty than Beijings's famous birds nest stadium, which doesn't.

So forget the living roof, the epitome of green design, even if you are trying to get on the cover of Architecture magazine, there is a substantial amount of man made material used in the construction of a living room. It might take a hundred years before the environmental benefits of a living roof negate the cost of creating it. 

Shaving tons of your next high rise may not get you any prizes. But at least you and your inner environmentalist will know you did the right thing.

Shut Up and Listen - the John Francis Story

John Francis became a UN Goodwill Ambassador (yes, a real title) in the most unlikely way - he stopped talking and started walking. His walking took him all over the United Stares and parts of South America. It all started after he witnessed the devastating effects of an oil spill in San Francisco Bay 1971. He gave up on motorized transportation. The he got so sick of arguing with people -- maybe do do the same -- that he then gave up talking. He remained silent for 17 years.

By the time I saw him addressing an audience of architects at an Imaginit -hosted event in NYC, he had given up his vow of silence. He was warming the stage for an evening centered on sustainability  and Autodesk's tools to help architects get in touch with their inner environmentalist. As Dr. John Francis' message was decidedly anti-technology, it was appropriate that a canned PowerPoint presentation suffered technical difficulty.  Undaunted, he strolled onto the stage strumming a banjo. 

He told how he had no idea what he wanted to accomplish back when he first started walking. Along the way, he actually acquired a Masters degree, then a PhD, even led a discussion group while a TA -- all without talking.

Eventually, John realized his self-imposed silence and transportation limitations were a "prison."  Having learned much from listening and travelling all those years, he was eager to spread the knowledge. His first words "Thank you all for coming" raised a "Hallelujah" from a relieved mother and made him spin around -- he didn't recognize his own voice or where it was coming from.

Takeaway: John was recruited by a US Coast Guard commission on oil spill regulation, thereby putting him in a position to prevent the very sort of thing that got him all riled up. Had he not undertaken the walking path, would he have been able to have as much impact? Do the right thing and paths and opportunities will open up, he says.

John has told his own story in a book entitled PlanetWalker, available at www.nationalgeographic.com/books. More about John on his website.

Bentley Annual Meeting - Small but Busy

CHARLOTTE, NC, October 13, 2009 - Bentley is piling it on. Eight press releases. It's 7AM. The coffee hasn't even kicked in. Some of us press are grumbling and I hear "I don't do morning."

So kicked off is Bentley's annual user meeting. It is substantially downsized from previous years. This year it is "invitation only." Users consist mostly of creators of exemplary projects, the kind that fill up Bentley's annual tome, The Year in Infrastructure. The awards will be presented during a dinner ceremony, an event retained from previous years and serving as focus of this year. Gone, however, is the popular conference aspect as classes have all gone online. 

Also present are 35 of the press, though not were able to get up so early. We're asked to stand up during the keynote.

A slimmed down Greg Bentley addresses a slimmed down annual meeting.But there's no shortage of information -- 8 announcements already.

A shame it couldn't be bigger. Bentley has so much to tell. It is the company's 25th anniversary. The company did the right thing by cutting back but a couple of thousand users would have made it a heck of  a party. Maybe next year. The event returns to Philadelphia next year (May 17-21, 2010).

I better scramble. Gotta process the press releases. 25 year anniversary, country licensing, 3 acquisitions. Damn, no graphics--I'll have to hunt some down.

Physics Based -- What the Hell Does that Mean?

I know about a little physics -- enough to be dangerous. Enough to wonder what people mean when they say their sofware is "physics based."

I hear "physics-based" a lot at the GPU Technology Conference. For example, virtual dummies, roughly the shape of humans, are being flung through virtual wall, much to enjoyment of the assembled. The "simulation" is termed physics based. It is said in a way that insists that, yes, that is exactly how a body would crash, how fast it has to be flung before the wall starts to break up, how the pieces of the wall fly through the air, etc.

Oh, yeah? I have not studied realism in crash test dummies personally. I have witnessed the effect of a large calibre bullet bust up a thick steel plate. The shock wave from the impact of the bullet made a chunk of the plate break off on the opposite side and fly around the room -- an effect known as spalling. I pondered the equations that would model the shockwave. They were intense. The modeling of a dummy through a wall -- hmm... let me see. You could assume the dummy is an articulated collection of rigid body masses but what about the point of contact? The local deformations would be key in determining local failure of the wall at point of impact so rigid bodies need not apply. The wall itself was not simple, composed of vertical structural members and several layers. This was a far more complex problem than my bullet/plate problem. 

Now do you think NVIDIA was solving all those equations. I think not.  It's for fun and games. The results will not protect crews in armored vehicles, or protect office occupants from catapulted bodies. (Didn't they use to dead plague victims into besieged cities?). We see more "physics" applied to splashing water. I think modeling fire and explosions is absorbing our brightest minds -- for the movie industry. 

It would be nice if the industry adopted a level of physics based. At the lowest level, say level 1, would be if F=ma could be found any where in the code, even if it used for only one object. At the highest -- and possibly unattainable theoretical limit -- the magical physics based level 10, where every molecule in the picture behaves according to known laws, with each contributing to the motion and interaction of the bodies of which they are part. 

Why Are the Smartest Guys Flying Fat Boy Scouts?

SAN JOSE, CA, Oct 1, 2009 - Does going to a really popular restaurant make you expect a good meal? But the waiter ignores you, the menu's in a different language and most of the entries are meat -- you've just turned vegetarian. All the other diners are having a great time, eating it up, and getting lots of attention. 

So it seemed at the sold out, standing room only GPU Technology Conference. I was curious how the GPU power very much in evidence was going to help CAD, CAM and CAE users. But I was feeling like the bastard child.

Stanford professor Pat Hanrahan tells us the hottest trends in visual computing are in movies and games. Are the smartest guys in the room using their brains to make sure the fat boy scout floats a house into the sky with a bunch of balloons? I'm hearing that was the funniest animated movie ever, but ---damn, shouldn't they be doing something important. I'm about to deliver yet another righteous rant about how really important design and engineering is in the scheme of things ...until it occurs to me that back at the office we are currently helping an inventor model a contraption that keeps piss from splashing on the walls of the bathroom. 

Or wait...maybe I can be righteously indignant after all. Piss on walls must be a real world problem -- unlike the house on  balloons. There must be thousands of maids cursing errant pissers in hotels. Or marraiges breaking up because the male of the house considers forceful urination his terrritory and the cleanup, someone else's.

The light bulb goes on: Instead of modeling water splashing trivially in a invisible cube, which is nothing but an excercise for the graphically gifted, why not model Pissing in Toilets. A splash resistant toilet is a worthy goal and could occupy the brighter minds among us. At least it would keep them out of the animation studios and game labs.