Archive for March 2012
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Steel Structure Trivia: Reigning Roof
Posted by Tasha Weiss on March 30, 2012 at 10:01 AM.
Here’s MSC’s second Steel Structure Trivia question! (We’ve decided to go a bit easier on you all for this one) Shown above is one of two 17-ft-wide by 35-ft-deep arch box trusses spanning 1,225 ft and supporting the world’s largest single-span roof structure. The question is: Can you identify what famous facility holds this retractable domed roof? Photo: Blake Marvin, HKS Inc.
Answer: This steel roof structure is part of none other than Cowboys Stadium in Arlington, Texas. (Not too far from where the upcoming NASCC: The Steel Conference will take place, April 18-20!) Congratulations to Jason Bastien with Professional Metal Works in Freeburg, Ill., Matt Thomas with Holabird & Root in Chicago, and Scott L., Texas A&M University, for being the first three people to submit the correct answer! And thank you to all who participated.
AISC member Walter P Moore served as lead structural engineer for the project. The $1.15 billion, 80,000-seat, three million sq. ft, retractable roof superstructure has set at least three structural engineering world records. It is the longest single-span roof structure in the world; it boasts the world’s largest center-hung HD video display board; and its operable glass doors are the world’s largest.
The 660,800-sq.-ft retractable roof features a 256-ft-wide by 410-ft-long roof opening. In addition, it has the first application of a rack-and-pinion retractable roof drive system in North America, which can open and close the bi-parting roof panels in less than 12 minutes.
The project received a President’s Award of Excellence in Engineering as part of AISC’s 2010 Innovative Design in Engineering and Architecture with Structural Steel (IDEAS2) program.
You can read an in-depth description of the project in the May 2010 issue of MSC, available at http://bit.ly/HkW7ZL, as well a feature article in the December 2008 issue, available at http://bit.ly/HHezih. For more images of Cowboys Stadium, visit our slideshow gallery at http://bit.ly/HC2hd6.
Think you have what it takes to win? You can test your steel structure knowledge right here on our MSC website on the last Friday of each month, where a new photo showing only a detailed portion of a steel structure will be posted to the Steel in the News section as our weekly “Steel Shot.” Your challenge is to correctly answer the trivia question provided in the news post, based on what you see in the photo. The next question will be posted at 10 a.m. (CDT) on Friday, April 27.
The first three people who supply the correct answer will receive an MSC-branded stainless steel back scratcher! You’ll need it to successfully tackle those pesky itches after the trivia pressure subsides. (And check out that telescoping action! Wow!) Its five-fingered curved design reaches from 7 in. to 20 3/4 in. in length.
Steel Supports Solar in SoCal
Posted by Tasha Weiss on March 29, 2012 at 2:32 PM.
A 3.72-MW steel-framed solar carport structure was completed last week at the West Los Angeles Veterans Affairs Medical Center, wrapping up Phase 1 of what will be the largest installation of solar canopies on a VA hospital in the U.S. Design-build contractor Build Group, Inc., performed the massive installation while keeping the parking lots in full operation.
In total, 6.8 MW of solar carports are slated for installation at the hospital, totaling 562,293 sq. ft of elevated photovoltaic surface area. The project design incorporates seven solar panels across each T-structure, compared to an industry standard of only six panels. By elevating more panels with the same amount of structure, the per-unit watt return is maximized for each structure. Also, the structure is designed to withstand winds of 85 MPH.
For more information about the project, you can view Build Group’s press release at http://bit.ly/GZeoQM.
Student Bridge Competitions in Full Swing this Spring
Posted by Tasha Weiss on March 28, 2012 at 11:27 AM.
The 2012 ASCE/AISC Student Steel Bridge regional competitions have kicked off, with four competitions held last week and 13 more set for the next five weeks. (This photo shows Tennessee Tech University’s bridge from the Southeast regional competition. Photo: Renee Whittenberger)
About 200 university teams participate in a total of 18 regional competitions (the first regional competition took place in January), and the top teams will qualify to compete in the finals at Clemson University, May 25-26. Now in its 21st year, the competition convenes engineering students from across North America to build their designed and fabricated steel bridges under the pressure of the clock.
There are plenty of opportunities to attend one of these exciting events! View the full schedule of upcoming regional competitions (including host school contact info) on ASCE’s website at http://bit.ly/z6uGHm. You can find out more about the national competition on Clemson University’s website at www.clemson.edu/ces/steel-bridge.
For more information about the 2012 Student Steel Bridge Competition, visit www.aisc.org/steelbridge or www.nssbc.info.
Last Day to Register for AISC’s Connection Design Communication Webinar!
Posted by Tasha Weiss on March 27, 2012 at 3:43 PM.
If you haven’t already registered for AISC’s live webinar, “Effective Communication of Connection Design,” tomorrow, March 28, you still have time! Online registration will remain open until 10 p.m. (PDT) tonight on AISC’s website at http://bit.ly/GWXvBO.
Presented by Patrick J. Fortney, Ph. D., P.E., manager of engineering and chief engineer at Cives Engineering Corporation, Roswell, Ga., the 1.5-hour webinar will cover common communication issues related to connection design contracts, and various solutions for effectively executing this type of complex contract, supported by techniques and examples provided in AISC’s Code of Standard Practice.
The webinar will begin at the following times, relative to your time zone:
10:30 a.m. PDT
11:30 a.m. MDT
12:30 p.m. CDT
1:30 p.m. EDT
The cost of the webinar is $185 for members, $285 for non-members and $155 for students and educators. (Fees are based on a per-site connection basis. Purchase one site connection and any number of members in your company or organization may view the webinar at that site connection. All attendees are eligible to receive CEUs/PDHs.)
Registrants will receive access to a PDF file of the presentation slides prior to the webinar, CEU/PDH certificates for all attendees upon completion of the live webinar (0.15/1.5 CEUs/PDHs) and complete instructions for accessing the live webinar.
To learn more about this live webinar, visit AISC’s website at http://bit.ly/GUdcug. More information about AISC webinars can be found at www.aisc.org/webinars.
Made in America? “Should Be!” Says New Campaign
Posted by Tasha Weiss on March 26, 2012 at 3:47 PM.
The “Should Be Made in America” campaign, created by the Alliance for American Manufacturing (AAM), was launched today at the new San Francisco-Oakland Bay Bridge, a massive construction project that was outsourced to China at the cost of thousands of American manufacturing jobs. The campaign urges the use of American-made components for infrastructure projects financed with U.S. tax dollars.
The National Steel Bridge Alliance (NSBA) has issued a public statement commending AAM for the new campaign:
“The campaign brings into focus how decision makers on the San Francisco-Oakland Bay Bridge financed the project with American tax revenues while circumventing Buy America provisions. This federal rule is designed to ensure that taxpayer-supported projects help the American economy. On this project, the bridge authority carefully segmented the job to ‘segregate’ the federally funded portion and allow the steel fabrication of the bridge to go overseas. Despite media claims, this project was not a success for American taxpayers. It’s far over budget, way behind schedule, and has resulted in the transfer of thousands of jobs and hundreds of millions of dollars from America to China.”
To learn more about the Should Be Made in America campaign, visit www.shouldbemadeinamerica.com.
Steel Shots: Accelerated Bridge Construction–Live!
Posted by Tasha Weiss on March 23, 2012 at 2:59 PM.
A live webcam view, looking from Indiana to Kentucky, of the existing Milton-Madison Bridge (at left) and one of the new steel truss spans being assembled, on barges, for the replacement bridge. (OK, this shot is from yesterday; today’s weather isn’t being as cooperative for a clear image.) Photo: www.miltonmadisonbridge.com
A 600-ft, 1,700-ton steel truss span for the new Milton-Madison Bridge is rising above the shoreline in Milton, Ky. Workers are currently assembling the new truss bridge on barges just west of the existing bridge and, once complete, the span will be floated a short distance upstream for replacement of the existing bridge.
Special jacks will lift the entire section into place onto temporary piers that are being built just downstream of the existing bridge. A second, 727-ft section of span will also be built and “lifted” in a similar manner; the remainder of the truss will be erected on top of the piers using cranes.
By early 2013, the new Milton-Madison Bridge, spanning the Ohio River between Kentucky and Indiana, will be closed for just a few days while it is slid sideways from the temporary piers, upon which it is being constructed, onto rehabilitated and enlarged original piers, after serving as the traffic detour while the old bridge superstructure is being demolished.
The sliding technique allows the project to be built while minimizing disruption to traffic, accelerating construction and reducing costs considerably for a bridge of this scale. (The four steel truss spans measure 2,430 ft and weigh 15,260 tons in all!)
You can track the bridge’s construction progress in real time via a live webcam on the project website at www.miltonmadisonbridge.com/gallery/live
-bridge-cam (the above image is from the view of “Live Bridge Cam 2.”). All images are automatically archived for public viewing (with cool zoom features!) and you can also watch time-lapse videos. There you’ll also find the latest news and other information about the project.
You can learn more about the bridge’s innovative sliding technique in the February issue of MSC. The article, “Move That Bridge,” explains how the decision to use this system stemmed from its success on the Capilano River Bridge project in Vancouver, Canada.
Smith Center Takes Center Stage in Vegas
Posted by Tasha Weiss on March 22, 2012 at 3:05 PM.
Las Vegas’ much-anticipated cultural centerpiece, the Smith Center for the Performing Arts, opened this month and is the first major multi-purpose performance center in the U.S. to earn LEED Silver certification. (Right Photo: Steve Hall, HedrichBlessing)
Inspired by many architectural styles, including art deco, the 358,000-sq.-ft Smith Center uses 4,000 tons of structural steel and nearly 2,500 tons of Indiana limestone. A 170-ft-tall Carillon tower (featuring 47 bronze bells and a stainless steel silver crown) provides somewhat of a town square feel, and several of the project’s details pay homage to the nearby Hoover Dam. (Left Photo: Courtesy of Walter P Moore)
Sited at the heart of 61 acres of environmentally remediated and reclaimed rail yards–the building is part of new urban development, Symphony Park, a 1.7-acre complex that will host performances and other entertainment events–the $470 million building houses multiple venues for a broad range of performance genres and events. The 2,050-seat Reynolds Hall will host orchestra, opera, dance, Broadway and first-run touring attractions from around the world, while the Boman Pavilion will play home to more intimate musical and drama settings.
You can find out more about the new Smith Center at www.thesmithcenter.com.
Steel Industry Leads U.S. Manufacturing Recovery
Posted by Tasha Weiss on March 21, 2012 at 4:20 PM.
America’s steel industry is leading manufacturing out of the recession, according to a new report by Timothy J. Considine, professor of energy economics, University of Wyoming.
Considine’s analysis, “Economic Impacts of the American Steel Industry,” finds the industry supported more than one million jobs in the U.S. economy in 2011 and is playing a significant role in leading manufacturing’s post-recession resurgence, primarily because it is highly interrelated with many other sectors of the economy.
The report reveals that each job in the U.S. steel industry supports seven jobs in the country’s economy, reflecting the industry’s ripple effect on employment. In 2011, the American steel industry directly employed 150,700 people and, given the multiplier effect, supported more than 1,022,000 jobs, as well as contributed $101 billion in gross domestic product and $246 billion in gross economic output.
Considine points out that the significant economic impact of the industry is based on the fact that steel is the most prevalent material in the economy, and the steel industry purchases a wide variety of inputs from other industries that create a favorable ripple effect. “This is one reason why so many countries around the world welcome investments that establish steel mills, because they stimulate industrial supply chains,” he said.
Considine’s analysis was commissioned by the American Iron and Steel Institute (AISI) to provide an updated look at the American steel industry’s overall impact on the U.S. economy.
Click here to read the full report.
Click here to read the Key Findings.
Thermal Bridging Addressed in New Free Resource
Posted by Tasha Weiss on March 20, 2012 at 1:08 PM.
Reducing energy usage in buildings has become one of the most widespread goals in the construction industry. While efforts in this area are typically focused on the mechanical, electrical and glazing systems and not the structural system, one area where structural designers can reduce energy consumption is thermal bridging–the loss of building energy via thermal conductivity of elements that “bridge” across the insulation of a wall or roof enclosure of a conditioned (i.e., heated or cooled) space when the outside temperature is warmer or colder than the interior space.
The joint Structural Engineering Institute (SEI)/AISC Thermal Steel Bridging Task Committee, in conjunction with the SEI Sustainability Committee’s Thermal Bridging Working Group, have produced a free resource, “Thermal Bridging Solutions: Minimizing Structural Steel’s Impact on Building Envelope Energy Transfer.” This document addresses thermal bridging issues in steel-framed structures and lists various solutions that can currently be evaluated and implemented.
The document is a supplement to the March 2012 issue of MSC and is available for free at http://bit.ly/GAZ7UH. You can learn more about the work of the Task Committee and other sustainability-related topics at www.seisustainability.org and www.aisc.org/sustainability.
Steel Shots: Spiraling Steel
Posted by Tasha Weiss on March 16, 2012 at 3:25 PM.
What on earth is this? It’s the “ArcelorMittal Orbit,” a 377-ft-high observation tower at Olympic Park in East London. Set to open for the 2012 Summer Olympics, the steel structure will be the tallest sculpture in the UK and will offer unparalleled views of the park and London’s skyline. Photo: ArcelorMittal
You may have already seen television commercials gearing up for the 2012 Summer Olympics, so we thought now would be a good time to reveal a glimpse of a towering steel structure that is expected to grab an equal amount of attention at Olympic Park in East London.
Sited between Olympic Stadium and the Aquatics Centre, the ArcelorMittal Orbit allows visitors to view the entire Olympic Park from two observation platforms. Designed by Anish Kapoor and engineered by Cecil Balmond, the tower represents a modern “twist” on combining architecture with structural engineering, where visitors can engage with its artistic expression via an incorporated spiral walkway.
Construction was completed late last year and the project is built with nearly 2,000 tons of steel, produced from ArcelorMittal plants around the world. Steel was the only material considered for this project because, according to Balmond, it was the only material that could provide the minimum thickness and maximum strength required for the coiling structure.
The tower is expected to open in May of this year, in time for the start of the Summer Olympic games.
You can find more information about the ArcelorMittal Orbit project, as well as galleries of construction photos and videos, at www.arcelormittalorbit.com.