Archive for May 2013
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Steel Structure Trivia: The First NSSBC
Posted by Tasha Weiss on May 31, 2013 at 11:31 AM.
Here’s MSC’s May Steel Structure Trivia question! The above is a flashback photo from the first-ever National Student Steel Bridge Competition (NSSBC), when Michigan State University hosted 13 teams. Things have come a long way in the competition since then (for instance, standing on the bridge is now against the rules!) but the level of action and excitement hasn’t changed a bit! Today and tomorrow, nearly 50 university teams will converge at the University of Washington in Seattle to compete in the 2013 NSSBC finals. Your trivia question is: What year did the NSSBC begin? Photo: Frank Hatfield
The first NSSBC was held in 1992. Congratulations to our winners: Aaron Daley, a civil engineering student at the University of Kentucky; Ryan Couto, a structural engineer with Parsons Brinckerhoff, Boston; and Matthew Turner, a UC Davis alumnus who was the head advisor and designer on the university’s 2007 steel bridge team, nicknamed “Chrome Ollie,” which took second place overall that year.
Our trivia challenge was sort of a trick question. We had a few people respond to us with the year 1987, which is technically when it all started, but with a local competition. Bob Shaw, then AISC director of university programs, arranged a student steel bridge competition for three Michigan universities: Lawrence Technological University, Southfield, Mich.; Michigan Technological University, Houghton, Mich.; and Wayne State University, Detroit.
Over the next four years additional schools joined the Michigan competition, and other local competitions developed throughout the country. Each of the local competitions claimed to have the best bridges in the country. To settle the issue, in 1992 Michigan State challenged all bridge teams to the first national competition in East Lansing, Mich.
Fromy Rosenberg, AISC director of university programs from 1990 to 2008, provided organizational, moral and monetary support for the competition. Thirteen teams competed and Michigan State won.
To learn more about the history of the NSSBC, you can read an article from our July 2011 issue.
Last weekend, the student engineering team from the University of California, Berkeley, were named champions in this year’s NSSBC, held at the University of Washington in Seattle.
You can view photos from the competition on AISC’s Facebook page at www.facebook.com/AISCdotORG in the “NSSBC 2013” photo album. More info on the results to come soon!
2013 NASCC Recorded Sessions Now Available
Posted by Tasha Weiss on May 31, 2013 at 9:27 AM.
While there’s no substitution for attending NASCC: The Steel Conference in person, AISC offers the next best thing. The proceedings document much of the material presented at the conference, including a synchronization of the speakers’ voices along with their visual presentations.
The recorded sessions from this year’s conference in St. Louis are now posted online at www.aisc.org/2013nascconline (you can find previous conference seminars by visiting www.aisc.org/freepubs and clicking on “NASCC: The Steel Conference”) and all are available in MP4 format.
Why does AISC do this? The Steel Conference is a bit different from other conferences. While most conferences issue a call for papers, consider abstracts, and then select those who will present a paper, The Steel Conference takes a different approach. The planning committee selects topics and then seeks out the top experts on those topics. As a result, we don’t require our presenters to produce papers. Instead, our proceedings are an actual documentation of the material presented at the conference. AISC then makes much of this material available at no charge as part of its mission to disseminate information that makes it easier to design and build with structural steel.
This year’s Steel Conference boasted a record-breaking attendance of 3,748 people. You can find photos from the conference on AISC’s Facebook page at www.facebook.com/AISCdotORG in the “NASCC 2013” photo album, as well as videos on AISC’s YouTube channel (www.youtube.com/AISCSteelTV) showing highlights from the opening day of the conference.
Next year’s Steel Conference will take place in Toronto, March 26-29, and will be held in conjunction with NSBA’s 2014 World Steel Bridge Symposium. To learn more about The Steel Conference, visit www.aisc.org/nascc.
Temporary Washington I-5 Bridge Replacement Underway
Posted by Tasha Weiss on May 30, 2013 at 4:58 PM.
Workers are already assembling a temporary Interstate 5 bridge span to replace the section that collapsed into the Skagit River near Mt. Vernon in Washington last week, according to an article published yesterday in The Seattle Times.
According to the article, steel plates, girders and truss beams were unloaded in stacks yesterday at the now-unused strip of freeway just north of the bridge, where officials say the first few parts are being fastened together.
The new crossing is being installed by Acrow (an AISC member), a New Jersey-based firm that specializes in the design, manufacture, and supply of modular prefabricated steel bridges. You can see how a temporary bridge is built via an animated video that shows how an Acrow bridge is erected on land, in a manner similar to a big erector set, then launched cantilever-style across the waterway.
Governor Jay Inslee announced the I-5 bridge replacement plan on Sunday: “We will install a temporary span on the bridge that will restore traffic while we build a safe and durable permanent span adjacent to it,” he said. “This plan ensures the economic vitality of Washington state and the communities along this important corridor.”
WSDOT says the temporary four-lane bridge will carry I-5 traffic over the Skagit River at a reduced speed and capacity. The bridge will consist of two, 24-ft-wide structures to replace the collapsed section of the bridge. These structures will be pre-built and trucked to the site to allow for accelerated installation. The remaining southern section has been examined and will not need to be replaced.
WSDOT released a visualization of the temporary replacement bridge.
If the remaining inspections of the bridge structure find no additional damage, the temporary bridge could be in place within weeks. Once debris has been removed, further underwater structural examinations will determine if additional repairs are needed before installing the temporary span.
Crews will immediately start work on the permanent bridge when the temporary span is put in place. They’ll put temporary piers into the river to support a platform adjacent to the collapsed span where the new section will be built. Once complete, the temporary span will be removed and the new permanent span will be moved into place. WSDOT hopes to have the permanent bridge open to traffic in early fall.
According to another article published on Monday in The Seattle Times, the permanent bridge will probably rest upon a half-dozen steel girders, each 160 ft long, that reach from the shore to the first in-water concrete pier.
Harvey Coffman, bridge-preservation engineer for the state Department of Transportation, said steel girders are preferred because they’re lighter than concrete girders, and therefore put less strain on the existing columns, built in 1955.
For additional information on the I-5 bridge replacement plan, see WSDOT’s news release.
Buckner Companies Chairman Wins Prestigious N.C. Award
Posted by Tasha Weiss on May 29, 2013 at 11:35 AM.
Eddie Williams, chairman of Buckner Companies (an AISC member and advanced certified erector), has received North Carolina’s Order of the Long Leaf Pine Award for his accomplishments, service and contributions throughout the steel industry.
Former N.C. Senator Bob Atwater presented the award on behalf of former N.C. Governor Beverly Perdue, stating, “One would be pressed to find any individual that has devoted more time, resources or effort working for the betterment of the steel construction industry.” (Photo: Former N.C. Senator Bob Atwater (left) with Williams. Courtesy of SEAA.)
The Long Leaf Pine Award, one of the most prestigious that a North Carolina governor can bestow, recognizes a citizen’s contributions to his or her community and dedication to his or her profession. Williams joins a notable rank of more than 7,000 recipients, including Billy Graham, Michael Jordan, Charles Kuralt and political cartoonist Doug Marlette.
Williams started working with C.P. Buckner Steel Erection, Inc., in 1952 where he began his career as a rebar laborer, eventually achieving the position of Chairman of the Board of one of the country’s most respected steel erectors. Williams made his way to the top by working in most every trade and management position within his company as well as holding leadership positions at virtually every major trade organization in the steel construction industry.
He is one of six founding members of Steel Erectors Association of the Carolinas that evolved into the Steel Erectors Association of America (SEAA), and even secured SEAA a voice on the SENRAC Committee, providing the organization the opportunity to influence the writing of OSHA law that would govern how the entire construction industry would conduct business for the foreseeable future. He has served as SEAA President three separate times, including as founding president in 1972.
Williams has served in many positions throughout his community as well as industry organizations including: past member of the Board of Directors for Alamance County’s Chamber of Commerce; President for American Subcontractor Association of the Carolinas (ASAC); member of AISC’s Roundtable and Certification Committee; and member of AISC’s NASCC: The Steel Conference Planning and Awards Committee.
He was recognized with the William Davis Service Award by SEAA for his numerous contributions to the association and in 2005, he was awarded an AISC Lifetime Achievement Award.
At age 79 he still serves on the Board of Directors for the American Subcontractors Association of the Carolinas and for the Steel Erectors Association of America.
He has been married for 60 years to Pat Williams. They have one daughter, Teri Atkins; one son, Douglas E. Williams; and five grandchildren. Following in his father’s example, Doug provides leadership as the current CEO of Buckner Companies, Inc.
NSBA’s Statement on the Washington I-5 Bridge Collapse
Posted by Tasha Weiss on May 24, 2013 at 2:57 PM.
During this initial stage of shock, we as representatives of the bridge industry are thankful there were no fatalities and pray for the speedy recovery of the survivors, as well as applaud the excellent rescue efforts.
At this time, the Washington State Department of Transportation is starting their investigation. Premature speculation about potential causes is neither appropriate nor productive. Rather, this is a time for careful, comprehensive engineering analysis and for rapid response to the human and transportation impacts of this disaster. NSBA and the steel industry stand ready to aid in any way we can and will share more information as it becomes available to us.
Whatever the eventual findings, this unfortunate event serves to graphically illustrate the decaying state of our country’s infrastructure – not only bridges, but also roadways and railroads across the country. NSBA is dedicated to reversing this deterioration by urging Congress to invest in infrastructure improvements that will make our nation’s transportation systems more efficient, robust and reliable.
Bill McEleney, Director, National Steel Bridge Alliance
Free Steel Connection Software Webinar on May 30
Posted by Tasha Weiss on May 23, 2013 at 4:34 PM.
StrucSoft Solutions, a developer and distributor of BIM software components, is offering a free webinar next Thursday for structural engineers looking to speed up design and verification of structural steel connections.
The webinar will provide an introduction to LIMCON, a Windows-based, graphical software tool that allows you to quickly and easily design and check steel connections in both SI metric and U.S. customary units, using the latest code from AISC 360-10 LRFD and ASD, BS 5950, AS 4100 and CAN/CSA-S16-09.
In this informational webinar you’ll learn how you can:
- Easily choose and plug in hundreds of standard steel connection types, including support for multiple-row moment and end plate connections
- Perform calculations in real time
- Check bolt and weld groups
- Check support for multiple codes
- View connections in realistic 3D
- Integrate detailing with DXF output
The webinar will begin at 2:30 p.m. EST.
For more information about LIMCON, visit www.strucsoftsolutions.com/products/limc
New ASTM Standard Enhances HSS
Posted by Tasha Weiss on May 22, 2013 at 5:05 PM.
ASTM has released a new HSS standard, A1085 - 13 Standard Specification for Cold-Formed Welded Carbon Steel Hollow Structural Sections (HSS), which will result in the production of improved hollow structural sections (HSS). This specification is a big step forward in simplifying HSS design and usage, thereby making it a more desirable option for HSS.
“We were committed to the development of the new ASTM A1085 specification as it was needed to improve the performance of HSS used in structural applications such as seismic load resisting systems, bridge structures and other dynamically loaded structures,” said Brad Fletcher, senior sales engineer with AISC member Atlas Tube. According to Fletcher, round and square members from 6 in. and up will likely be the main shapes Atlas initially produce under the new specification.
Tighter material tolerances and a single minimum yield stress of 50 ksi. Because of the more stringent wall tolerances and the addition of a mass tolerance, it’s anticipated that AISC’s Committee on Specifications will shortly issue guidelines allowing the full nominal wall thickness can be used for design of HSS. This means no longer needing to reduce the nominal wall thickness by 0.93 as prescribed in the AISC Steel Construction Manual for both member selection and connection design. And more area available for design and a higher minimum yield mean that HSS will become a more economical and efficient design option.
Maximum specified yield stress of 70 ksi. This will result in a lower expected yield strength for seismic design, and thereby reduce capacity design requirements when HSS are the yielding element. For example, with ASTM A1085 HSS braces in a braced frame, the beams and columns will have lower required strengths. ASTM A1085 is the only HSS specification used in North America or Europe that limits the maximum yield stress.
Standard requirement for notch toughness. The specification will require all HSS to meet a minimum Charpy V-notch (CVN) value of 25 ft-lb at 40 degrees Fahrenheit, which corresponds to AASHTO Zone 2 requirements. Having the minimum CVN required makes HSS more suitable for use in dynamically loaded structures.
“A1085 makes designing with HSS easier and more efficient for both building and bridge construction,” said John Simon, vice president of sales with AISC member EXLTUBE. “We are hearing a great response from structural engineers who have begun to learn about this new spec through efforts at NASCC: The Steel Conference and other communications, and we’re working closely with AISC and the Steel Tube Institute to begin promoting A1085 to our customers. EXLTUBE will be supporting these efforts with inventory as soon as we’ve determined the sizes the market will require from us.”
John Tassone, marketing manager for AISC member Independence Tube, also commented: “We will be manufacturing and inventorying the product as the need arises,” adding that the company will likely concentrate on squares and rounds 4 in. and above to start.
For specific price and availability information, please contact HSS producers and service centers. Contact information is available at www.aisc.org/hss.
AISC Achievement Awards Video
Posted by Tasha Weiss on May 22, 2013 at 1:48 PM.
Every year since 1999, AISC’s Lifetime and Special Achievement Awards have been given to outstanding industry professionals for their exceptional contributions to the advancement of the structural steel design and construction industry.
You can see what some this year’s winners had to say about their awards and achievements, favorite parts of their jobs and more via a new online video. You’ll also hear from a few of the industry experts who serve on the selection panel and learn about what they look for in award candidates.
This year, 10 leading professionals were honored for making a difference in the fabricated structural steel industry’s success and were presented with these distinguished AISC awards at the 2013 NASCC: The Steel Conference last month in St. Louis.
Photos of all of this year’s award winners and additional information about their achievements can be found in AISC’s press release.
Engineering Journal Q2 Now Online
Posted by Tasha Weiss on May 21, 2013 at 9:41 AM.
The second quarter 2013 issue of Engineering Journal is now available online. Did you ever wonder how EJ got its name when it started 50 years ago? You can find out in this issue.
Papers in EJ Q2 include:
- Flange Bending in Single Curvature by Bo Dowswell
- Buckling Restrained Braced Frame with All-Bolted Gusset Connections by Patrick S. McManus, Addison MacMahon and Jay A. Puckett
- Uncertainty in Life-Cycle Assessment Induced by Life-Cycle Inventory Data: The Case of Structural Steel by Iordanis Zygomalas and Charalambos Baniotopoulos
- Current Steel Structures Research No. 33 by Reidar Bjorhovde
Article searches for the complete collection of EJ remain available at www.aisc.org/ej. Downloads of current and past articles in PDF format are free to AISC members and ePubs subscribers. Non-AISC members may subscribe to Engineering Journal at AISC’s website.
Is there a steel design topic that you would like to see addressed in more detail? EJ is always looking for your ideas. Email them to Keith Grubb, editor, at firstname.lastname@example.org.
Steel Shots: Going Big in Ohio
Posted by Tasha Weiss on May 20, 2013 at 11:39 AM.
The largest project in Ohio DOT history replaces an historic Cleveland crossing - the Interstate 90 Innerbelt Bridge - with a new delta girder bridge. The above photo shows a perspective of the “knuckle” portion of a delta girder at AISC member fabricator High Steel Structures’ shop. The new westbound portion of the bridge under construction will use 20,000 tons of structural steel in all. Photo: Courtesy of High Steel Structures
Interstate 90 provides major east-west access over the Cuyahoga River and through downtown Cleveland via what has become a functionally obsolete 1959 deck truss, thanks to a nearly 40% increase in vehicular traffic. Originally designed to carry a maximum of 100,000 vehicles daily, it now handles more than 138,000 cars a day.
When it came time to replace the historic structure, citizens were asked to vote on three steel alternatives: a cable arch scheme; a design with the deck supported on a series of slender, parallel beams spanning from pier to pier; and a delta girder scheme (the latter won). According to Dave Lastovka, project manager for the Ohio Department of Transportation (ODOT), the design is intended to complement Cleveland’s historic collection of steel river bridges while honoring steel’s role in the region’s economy.
At $640 million, which includes $79.4 million in American Recovery and Reinvestment Act funds, replacing the I-90 Innerbelt Bridge is the largest single infrastructure investment in ODOT history. And because the project is so large, ODOT broke it into two: a westbound bridge, which is under construction, and an eastbound bridge, scheduled to begin later this year.
The design-build team of Walsh Construction and HNTB Corporation (the latter also designed the original Innerbelt Bridge) was awarded the westbound bridge contract in September 2010.
The June issue of MSC (available June 1) will feature additional photos and detailed information about the Interstate 90 Innerbelt Bridge replacement project; stay tuned!