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
Multifamily Housing | May 5, 2022
An Austin firm touts design and communal spaces in its student housing projects
Rhode Partners has multiple towers in various development stages.
Legislation | May 4, 2022
Washington is first state to mandate all-electric heat for new large buildings
Washington recently became the first state to require all electric heat for new buildings.
Building Team | May 4, 2022
Mancini Acquires Gertler & Wente Architects, Expanding the Firm's Opportunities in New Market Sectors
National design firm Mancini Duffy - with a 100+-year-old history and tech-forward approach based in New York City - announces the acquisition of Gertler & Wente Architects to further expand its footprint in the healthcare, multi-family residential, restoration, institutional, and religious sectors.
Contractors | May 4, 2022
CFC Construction names Pat Smith president
CFC Construction is proud to announce that Pat Smith has been promoted to President of the Colorado-based general contractor.
Sponsored | Healthcare Facilities | May 3, 2022
Planning for hospital campus access that works for people
This course defines the elements of hospital campus access that are essential to promoting the efficient, stress-free movement of patients, staff, family, and visitors. Campus access elements include signage and wayfinding, parking facilities, transportation demand management, shuttle buses, curb access, valet parking management, roadways, and pedestrian walkways.
Sponsored | BD+C University Course | May 3, 2022
For glass openings, how big is too big?
Advances in glazing materials and glass building systems offer a seemingly unlimited horizon for not only glass performance, but also for the size and extent of these light, transparent forms. Both for enclosures and for indoor environments, novel products and assemblies allow for more glass and less opaque structure—often in places that previously limited their use.
Architects | May 3, 2022
A U.K.-based design firm flaunts industrialized construction as it expands into U.S.
Bryden Wood wants to set up a network for manufactured components for repeatable building types.
Codes and Standards | May 3, 2022
American Institute of Steel Construction updates environmental product declarations
The American Institute of Steel Construction has released updated environmental product declarations (EPDs) “to help designers and building owners design more environmentally friendly buildings and bridges,” according to an AISC news release.
Education Facilities | May 2, 2022
Texas School for the Deaf campus gateway enhances sense of belonging for deaf community
The recently completed Texas School for the Deaf Administration and Welcome Center and Early Learning Center, at the state’s oldest continuously operating public school, was designed to foster a sense of belonging for the deaf community.
Codes and Standards | May 2, 2022
Developer Hines, engineer MKA develop free embodied carbon reduction guide
Real estate management and investment firm Hines has released the Hines Embodied Carbon Reduction Guide. The free guide, produced with Magnusson Klemencic Associates (MKA), is the result of a two-year effort, relying on MKA’s industry-leading knowledge of carbon accounting and involvement in programs such as the Embodied Carbon in Construction Calculator (EC3) Tool.