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.
Benefits include:
- 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°F, 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.
About the American Institute of Steel Construction
The American Institute of Steel Construction, headquartered in Chicago, is a not-for-profit technical institute and trade association established in 1921 to serve the structural steel design community and construction industry. AISC's mission is to make structural steel the material of choice by being the leader in structural steel-related technical and market-building activities, including: specification and code development, research, education, technical assistance, quality certification, standardization, and market development. AISC has a long tradition of service to the steel construction industry of providing timely and reliable information.
Related Stories
| Aug 16, 2022
DOE funds 18 projects developing tech to enable buildings to store carbon
The Department of Energy announced $39 million in awards for 18 projects that are developing technologies to transform buildings into net carbon storage structures.
| Aug 16, 2022
Multifamily holds strong – for now
All leading indicators show that the multifamily sector is shrugging off rising interest rates, inflationary pressures and other economic challenges, and will continue to be a torrid market for design and construction firms for at least the rest of 2022.
| Aug 16, 2022
Cedars-Sinai Urgent Care Clinic’s high design for urgent care
The new Cedars-Sinai Los Feliz Urgent Care Clinic in Los Angeles plays against type, offering a stylized design to what are typically mundane, utilitarian buildings.
| Aug 15, 2022
IF you build it, will they come? The problem of staff respite in healthcare facilities
Architects and designers have long argued for the value of respite spaces in healthcare facilities.
| Aug 15, 2022
Boston high-rise will be largest Passive House office building in the world
Winthrop Center, a new 691-foot tall, mixed-use tower in Boston was recently honored with the Passive House Trailblazer award.
Architects | Aug 12, 2022
Goettsch Partners names James Zheng, CEO, and Paul de Santis, Co-design Director
Global architecture firm Goettsch Partners (GP) announces that James Zheng, AIA, LEED AP, has been named CEO, and Paul De Santis, Assoc. AIA, LEED AP, joins James Goettsch, FAIA, as co-design directors for the practice. As the primary partners in the firm, the three have worked closely together for more than 17 years. Goettsch will also continue to serve as chairman while Zheng now assumes the full CEO title as well as president.
| Aug 12, 2022
Monthly Construction Input Prices Decreased 2% in July, Up 17% From a Year Ago, Says ABC
Construction input prices decreased 1.8% in July compared to the previous month, according to an Associated Builders and Contractors analysis of U.S. Bureau of Labor Statistics’ Producer Price Index data released today.
Hotel Facilities | Aug 12, 2022
Denver builds the nation’s first carbon-positive hotel
Touted as the nation’s first carbon-positive hotel, Populus recently broke ground in downtown Denver.
| Aug 11, 2022
Report examines supposed conflict between good design and effective cost management
A report by the American Institute of Architects and the Associated General Contractors of America takes a look at the supposed conflict between good design and effective cost management, and why it causes friction between architects and contractors.
Architects | Aug 11, 2022
Mancini Duffy Bill Mandara on expanding through diversification
In this segment for HorizonTV, BD+C's John Caulfield interviews Mancini Duffy's CEO and Co-owner William Mandara about his firm's recent growth, which includes an acquisition and new HQs office.