Iconic Structures of Indiana: IND Airport

The Indianapolis Midfield Terminal is a lesson in successful long-term infrastructure planning. The site of the airport was picked in the 1930's, the "temporary" terminal was built in 1957, the upgraded control tower was finished in 2006, and the current terminal was finished in 2008. The current location was picked over 70 years ago, and the wait has been worth it.

South elevation and main entry

As is customary, I would like to refer readers to my fellow Indianapolis A/E bloggers and their thoughts on the new airport:
Urbanophile (start here and find links to all 7 pieces)
Circles & Squares (pre-construction review here, great photos too)

The new terminal is a great piece of infrastructure because it has made the Indianapolis Airport one the most convenient, comfortable, and successful airports ever. The iconic structural elements including the exposed roof trusses, vertical bowstring trusses, and eccentric braces give it an open, industrial grandeur. The structural system is easy to comprehend and the building feels safe and comfortable inside.

Interior of plaza (construction)

One of my favorite structural features is the column/brace system supporting the main roof. Depending on which direction is considered, the members will act as a column or an eccentric brace, and no moment connections were required. The trusses above did require a little bit of extra detailing, I'm sure, but everything looks great and I'm sure the system performance had to meet strict requirements with all those windows.

Brace columns and skylights

Pin connections at column base

I asked the original designers about these columns. I never got a clear answer about what seismic classification was used, but I would bet they considered them eccentric braces. The connections were designed as conventional pins per AISC specifications. They pointed out that while the trusses and braces were different from typical construction, the contractors were experienced with this type of construction and thus construction problems were limited.

Another unique element used on the airport is the vertical bowsting truss. These trusses are used on the huge expanse of glass fronting the passenger drop-off area, resisting the large wind forces that develop on this face. The open web design matches the architectural style of the interior, and the ratio of open-ness allows natural light to filter throughout the building.

Bowstring window trusses near public plaza (construction)

Vertical trusses near front entry (construction)

Much of the project was LEED registered (still awaiting USGBC confirmation), and it is clear that some sustainable thinking went into the project. A good writeup of the Airport's efforts towards acquiring LEED certification is here, or you can visit Blackburn Architects who were responsible for managing the LEED documentation (but you must use IE not Firefox).

Roof detailing on eastern side (construction)

Braced column supports and art space below (construction)

This was the first terminal to open under the new regulations passed since the 2001 terrorist attacks. A great deal of planning went into ensuring this airport would be able to meet all of the new regulations enacted to tighten security. Several areas of the airport are hardened against natural and manmade hazards, and new technology rapidly screens problems out of the system in case anything strange is found.

Tornado shelter entry

The front approach from Interstate 70 is convenient, and the traffic arrangement on the airport property is simple yet logical. Economy and long-term parking is the first option, and it sits in a field dominated by the new control tower. The tower makes it easy for people to orient themselves, even with the tall berms obscuring any other visual landmarks.

Air traffic control tower

Next up is the parking garage. This pre-stressed concrete structure has some really cool features that raise it above the banality of most parking structures. Several locations are high-lighted by tensile membrane roofs. The corkscrew vehicle ramps add flair to the southern corners, while the central pedestrian area is covered by another fabric roof. This central pedestrian area is actually quite attractive. There are automated people movers, glass enclosed elevators, kinetic sculptures, and a ground transportation center directly across from the main terminal.

Corkscrew vehicle ramp membrane structure

Tensile membrane roof over parking structure

The bridge structure linking the parking structure and the terminal is basically a trussed pedestrian bridge. Automated people movers and a central aisle are covered with an amazing bit of public art. This multimedia installation involves sound, light, movement, and sense of awareness that makes the traverse across the bridge an interesting experience. The bridge delivers travelers to a mezzanine level with escalators heading up or down.

Pedestrian bridge and front entry (construction)

The up option delivers another great experience as the expansive main plaza opens to view as you raise up to the main floor level. This room contains all of the ticketing areas and while there is no easy way to find where each airline is but the area is small enough, and interesting enough, to encourage a bit of exploration.

Main ticketing and entry lobby (construction)

On the way towards the gates and security areas is the circular plaza that establishes a special place within the airport. The circular public area is surrounded by retail and food establishments, which is one of the best public spaces in the city. The translucent roof panels add natural light to the space, and the hanging arts offers a visual reward for looking upwards.

Sky plaza

My favorite part, however, is the elevated catwalk that rings the public space. This links the administrative areas on the east and west wings, but it adds a new dimension of walkable space that really helps to enclose the area. It is a shame that the city has not learned how to apply these concepts to the cityscape, there are many places that could be reclaimed for pedestrians in a simlar manner.

Public space lined with shops

Upper walkway with torque-tube (construction)

Passengers can go through security at either concourse, each has plenty of queuing room and the latest equipment that speeds people through the checks. This in contrast to the previous Indianapolis security experience, and to many other airport terminals around the country which were not built to handle the new security provisions. Both security check areas have a large mosaic that adds visual interest.

View of the sky plaza and terminal from the tarmac (construction)

The A/B terminals offer a more typical experience, each gate has a seating area and the central area is taken up by automated people movers. The best part about these wings is the high ceilings and exposed structural members. The roof trusses and use of glass really shows the modernity of the airport. Once again, this is a night and day contrast with the previous Indianapolis terminal. While the overall feeling is still an industrial and impersonal one, the space is less depressing and fills travelers with confidence rather than despair.

Terminal A with Automated People Mover

Terminal structure with eccentric braces and steel trusses

Incoming passengers can easily find their way to the baggage claim. The automated baggage handling system takes up most of the space below the main floor. The system quickly routes each incoming and outgoing bag to the correct destination. It is so quick that it is possible for your bag to be waiting for you at the baggage claim before you are even on your way down the escalator. Siemens designed and installed the baggage system (more info here).

Braced steel frames and mechanical systems in lower level (construction)

One small turn within the 13,000 foot baggage handling system (construction)

The passenger pickup and dropoff area has been used to showcase even more structural elements. The cantilevered bus stops are similar to units covering the ticketing areas, tying the different areas together with a cohesive architectural style. The pickup/dropoff area has a great vista to the south, but it doesn't feel too open because the large glass backdrop provides a sense of enclosure.

Lower level exit from baggage claim to ground transportation

In general, one of the reasons that the airport seems so large is that people move through it so quickly that there are no large crowds of unhappy travelers. The limited time I have spent in the airport has been full of the typical travel issues: tickets lost in the computer system, baggage fees, expensive long-term parking, and neck cramps after falling asleep on the plane. But, it is all much more bearable when you aren't trapped in a building that looks as much like a military bunker as it does a functional piece of transportation infrastructure.

Baggage claim area (construction)

Baggage claim area

The airport managers realize that long-term planning allowed Indianapolis to accommodate the future growth of the airport corresponding to the growth of the city. They have further realized that expansion may be necessary in the future. This future expansion is provided for by adding extra gates in the A/B concourses. Room for an extra runway is located across the interstate.

The unused space between the parking structure and the nearest parking lot is expected to be taken up by a special-purpose hotel and convention center. I have even heard that there is an on-site location that can be used to link up to a mass transit system. If you don't think that is the definition of long-term planning, then you haven't spent much time in Indianapolis.

ASCE Plans Green Design Certification Program

The latest news about sustainability in the engineering industry is from the ASCE Smartbrief entry about ASCE initiative. By the way, the smartbrief newsletter is a great service and I strongly encourage you to sign up. Back to the issue at hand... the ASCE Sustainability Task Force has decided to create a new program that will "certify civil works". The ASCE president wrote (see blog post here) the following to explain the reasoning for this action:

We believe that ASCE and civil engineers should be the ones who establish good practices related to civil works.
...
We went green long ago; we just did not take credit for it.
...
If we fail to act, many other professions will be happy to do it for us and impose their ideas on our practice. We know better than others how to use our skills to benefit mankind by creating energy efficient and environmentally sensitive projects. Now, we will do just that.

I am a big fan of sustainability and green design, but I don't know if ASCE's certification program is such a good idea. For starters, if they want to emulate the LEED program then they are about 10 years away from market uptake, and probably 15 years from market penetration (and that is no guarantee). It took the USGBC quite a bit of effort and time to achieve consensus on how to define sustainability, and even longer to market the program to construction professionals. To assume that ASCE can replicate this process in the same time period is ridiculous. This plan cannot be ultimately successful because we are already too late. We must lower our CO2 emissions quickly, I don't see this plan catching up to the LEED program in time to make a difference.

Also, Klotz's own blog post betrays the real state of our profession. "We went green long ago... Now, we will do just that" [use our skills to benefit mankind by creating energy efficient and environmentally sensitive projects]. So did we really go green long ago, or are we just starting now? Let's just say I'm not convinced.

Another problem is that the ultimate goal has nothing to do with sustainability, but "communicating that fact to the public". It sounds like a PR gimmick from ASCE. It also sounds like a "me too" plan that does not have any original thought involved. If the ASCE sustainability task force is truly interested in sustainability, why is their best and most exciting piece of news that they are reproducing a program that someone else already does well?

The next problem I see is that this program may not be compatible with LEED Accreditation. The USGBC has spent a lot of time and money making sure their own program promotes sustainability in the construction industry, but also social and ecological sustainability. Studying for the LEED program promotes a greater understanding of what other professionals in the design field are concerned about. If civil engineers withdraw from that process then we are losing the greatest benefit of the LEED program, and certainly not learning a key lesson of the past years. Integrate, don't isolate.

Klotz believes that "civil engineers should be the ones who establish good practices related to civil works" and that "We know better than others how to use our skills to benefit mankind". I actually don't agree. Engineers are technical specialists, we use applied science. Engineers cannot exist in a vacuum, we can't set design criteria without collaboration with other fields. ASCE cannot unilaterally decide how to balance life safety versus sustainable design goals, this requires a public debate involving others.

I haven't seen any of the proposal beyond this short release by the president, but to move forward quickly on this proposal would require a top-down decision totally within the ASCE organization. That would concern me as well. We cannot be responsible for setting criteria, designing our structures to meet those criteria, and then judging if we met our own criteria. That kind of system has no oversight and no motivation to raise the standards once they have been set.

Most importantly, it would represent a slap in the face of the other building designers (architects, mechanical engineers, etc.) who have been trying very hard to get us to work together. This "we know better" attitude is dangerous, and is the very reason that others are already trying to "do it for us and impose their ideas on our practice". If ASCE wants to effectively manage sustainability then we need to extend our arms to all of the building design team and start learning what the others need and how we can support their efforts. Trying to siphon off of USGBC's hard work for our own glory is not my idea of a good long-term strategy.

Obviously ASCE's Sustainability Task Force did not consult me before they made their decision, but here is what my advice would have been:

1. Look to support other initiatives that have already achieved success (LEED, Energy Star, etc.) rather than beginning a separate certification program. Put all of your effort into supporting those programs and finding a way to create synergy.
   
2. All members of ASCE's Sustainability Task Force should have achieved LEED AP status by now. LEED AP's all learn a common language and use that to communicate their goals effectively. Klotz himself has a real chance to be a leader by acquiring LEED AP+ status, showing that he is serious about the process.
   
3. ASCE needs to define what metric they are using to determine sustainability: CO2 emissions, energy use, money saved? I don't see the ASCE organization achieving internal consensus anytime soon, just look at the comments on the blog page. Few engineers even believe the IPCC statements about anthropogenic CO2 emissions. It will be an uphill battle to say the least.
   
4. ASCE should plug into the LEED program by determing baseline material needs for different building types similar to the energy baseline models used in the EA sections of the LEED programs. This would provide the most effective way for engineers to determine if they are truly creating sustainable designs or overbuilding all of their structures.
5. Start an open dialogue about conflict of interests in the construction industry. Should an individual engineer be able to receive pens, pencils, and other marketing packages from material suppliers that might influence their decisions? Should an engineer be allowed to work for the ACI, AISC, or any organization that makes money from the amount of materials sold? Engineers are not so different from other professionals in this regard, and AMA is addressing this issue right now.
   
6. Start asking professionals who are not civil engineers: "how can I support your efforts?"

Let me finish by saying I think that ASCE took a very important position by including sustainability in their 1996 code of ethics (see my earlier post & post about this topic). While it is wishy-washy language that would never hold up in an ethics investigation, at least they were trying. You can see how difficult this was for them to accomplish by checking the NCSEA model code of ethics. It is very similar to those of ASCE except that every provision regarding sustainability is noticeably absent.

Role of Structural Engineers in Sustainable Construction

As more and more structural engineers have been considering their role in sustainability, there have been more resources available. The best sources of useful information concerning structural engineering and sustainable development are the May and June editions of Structure Magazine. This printed publication is made available freely to all NCSEA and SEI members, but anyone can access the online articles.

Sustainability articles typically address either the entire design process or specific strategies. This provides a convenient way to separate them into categories. First up, we have the articles that address design in general:

Overall Design Strategies
Once again, Structure Magazine leads the way with an article "Sustainable Buildings and the Structural Engineer." This article delineates all of the issues that sustainable develop should address and then shows how the structural engineer can impact the design. This is a great way to see all of the ideas laid out in one easy to grasp format.

Another article that I found useful is hosted at GoStructural.com (publisher of the trade magazine Structural Engineer). This is actually a collection of articles all on the same topic of sustainability.

Reuse of existing structures
One of the great things about sustainable development is that it recognizes the importance of historic preservation, or retaining existing buildings of any type. You may have heard the expression "The greenest building is one that's already built." This is the title of an article published by the National Trust for Historic Preservation, written by Carl Elefante. It's a great introduction into how these two topics work together, and a great rallying cry for those who feel that LEED credits don't properly address the issue.

Building on this call to reuse rather than tear-down and rebuild, another Structure Magazine article "Missed Opportunities in Structural Sustainablility" quantifies exactly how effective it would be to reuse a building. The bottom line: very effective. Essentially, this article shows that tearing down a building in just about any condition is the least green thing that can be done.

The National Trust for Historic Preservation has issued a whitepaper laying out exactly why reusing buildings is sustainable, extending the definition to include economics, social benefits, and environmental benefits. Another great read for people looking for ways to change policy and public opinion.

Lastly, the NTHP has put up a fun slideshow of pictures of structures submitted by readers that show promise for renovation or adaptive reuse. So here is Reuse it! (a Flickr group). Feel free to add your own.

Minimizing use of materials
An interesting editorial in Structure Magazine on the topic of "Voided Two-Way Flat Plate Slabs". This is a particular strategy of sustainable design called dematerialization. Basically, if you consume fewer resources for a building of similar strength then you are doing good for the environment. Of course, you can't put that sort of strategy into a ratings system (e.g. LEED) because then every engineer will claim they are using less material. The USGBC handled this problem in other trades by creating a baseline case, so the strategy may still work for structural engineering. But few people want to encourage engineers to use less material, so it probably won't be included for that reason.

Maximizing material effectiveness
Another interesting Structure Magazine article addresses materials that act as structure, insulation, and soundproofing. "The Road to Code Acceptance for Autoclaved Aerated Concrete" details how AAC is being (slowly) approved by code provisions, as well as how to use it in your buildings even today by getting a per-project approval from your local jurisdiction.

And finally, news from the Pakistan Straw Bale and Appropriate Building (PAKSBAB). This group has more of a "damn the torpedoes" mentality because there really are no trade groups that would profit from such a low cost building material. So the only way this type of material will ever get used is from prototypes and bona fide living experiments. I wish them the best of luck!

Examination Complete

I have successfully passed the LEED NC examination, so as a reward I am now reviewing the LEED 2009 program. I didn't let myself look at it until today, I was worried I would get the old and new mixed up right before my test. But now it's all good...

The new LEED 2009 (or version 3) program look pretty solid. They have completely changed all of the certification thresholds and added regional credits. The old credits have been altered so the ones that are more effective are weighted heavier. Check it out sometime.

I'll be back next week to bask in the glory of new business cards and a busy work schedule. Until then, I am heading out of state for a vacation.

Still studying

Still busy studying for LEED AP exam, no posts for another week.