June 2022 - American Institute of Steel Construction
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June 2022
June 2022
in every issue features
departments
30 Immersive Installation
6 EDITOR’S NOTE BY JOHN JUCHA, SE,
9 STEEL INTERCHANGE SHAUN FRANKLIN, PE, AND
12 STEEL QUIZ MICHAEL OLSEN, PE
Steel helps arts and entertainment
62 NEW PRODUCTS
company Meow Wolf achieve its
63 NEWS & EVENTS
immersive vision with a quirky new
66 STRUCTURALLY SOUND venue on a tight site in Denver.
resources
65 ADVERTISER INDEX 36 Treading Lightly
BY BRETT SAUTER, SE, PE
65 MARKETPLACE A Chicago bridge project powers
& EMPLOYMENT through COVID-19 impacts while
minimizing its own impacts on the
train and highway traffic it traverses.
40 Faster and Faster
BY BRETT MANNING, SE, DAVE P.
WRIGHT, KEITH D. PALMER, SE, PHD,
AND RYAN COOKE, PE, PHD
An already speedy steel plate
core system becomes even faster
thanks to an innovative “split”
planning mindset.
40 48 Hillside Steel
BY RALPH PARRISH AND
ROBERT HORTON, PE, PENG
A new steel fabricator headquarters
building is both carved out of and
columns blended into the foothills of the
steelwise field notes Appalachians.
16 Are You Properly Specifying 26 Intercontinental Connection
Materials? INTERVIEW BY GEOFF WEISENBERGER
Gian Rassati, a 2022 AISC Special
54 Navigating Sustainability
BY LAURA MICHELI, PHD, BRUCE
BY JONATHAN TAVAREZ, PE
Learn what’s new in the world of structural Achievement Award winner, began life in a BROTHERSEN, SE, PE, PENG, AND
steel materials. small Italian mountain town and has gone on SCOTT RUSSELL, SE, PE, PENG
to do big things in bolting research. Notes on navigating the evolving
data driven sustainability landscape.
business issues
24 Rough Waters
BY JOE DARDIS 28 A Letter to Entry-Level Engineers 60 And We’re Back
As we navigate the turbulent seas of BY RYAN CURTIS, PE BY GEOFF WEISENBERGER
construction pricing, remember that we’re all Advice for today’s young engineers on NASCC: The Steel Conference
in the same boat. their way to becoming tomorrow’s returns to an in-person format for
engineering leaders. the first time since 2019.
ON THE COVER: It’s a tight squeeze for a new Denver museum located on a sliver of land between highways, p. 30.
(Photo: KL&A Engineers and Builders)
MODERN STEEL CONSTRUCTION (Volume 62, Number 6) ISSN (print) 0026-8445: ISSN (online) 1945-0737. Published monthly by the American Institute of Steel
Construction (AISC), 130 E Randolph Street, Suite 2000, Chicago, IL 60601. Subscriptions: Within the U.S.—single issues $6.00; 1 year, $44. Outside the U.S. (Canada and
Mexico)—single issues $9.00; 1 year $88. Periodicals postage paid at Chicago, IL and at additional mailing offices. Postmaster: Please send address changes to MODERN
STEEL CONSTRUCTION, 130 E Randolph Street, Suite 2000, Chicago, IL 60601.
DISCLAIMER: AISC does not approve, disapprove, or guarantee the validity or accuracy of any data, claim, or opinion appearing under a byline or obtained or quoted
Printed on paper made
from an acknowledged source. Opinions are those of the writers and AISC is not responsible for any statement made or opinions expressed in MODERN STEEL from a minimum of
CONSTRUCTION. All rights reserved. Materials may not be reproduced without written permission, except for noncommercial educational purposes where fewer than 25 10% recycled content.
photocopies are being reproduced. The AISC and Modern Steel logos are registered trademarks of AISC.
4 | JUNE 2022
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editor’s note
Editorial Offices
130 E Randolph St, Ste 2000
If you were a teen (or like me, Chicago, IL 60601
312.670.2400
had teenage or pre-teen kids) Editorial Contacts
CHIEF EDITOR
a decade ago, you were Geoff Weisenberger
312.493.7694
probably all too aware of a weisenberger@aisc.org
handful of mildly entertaining, PUBLISHER
Keith A. Grubb, SE, PE
mostly harmless Nickelodeon 312.804.0813
grubb@aisc.org
shows such as iCarly GRAPHIC DESIGN MANAGER
Kristin Hall
and Victorious. 773.636.8543
hall@aisc.org
EDITORIAL DIRECTOR
What you probably aren’t aware of is that more have carbon footprints around half the industry Scott Melnick
recently, millions of people like my youngest son world average (by comparison, Chinese steel has 312.804.1535
melnick@aisc.org
have watched hours and hours of online videos roughly three times the greenhouse gas emissions
talking about these shows. These videos include of American steel). AISC Officers
recaps longer than the actual episodes, as well as And improvements are steadily advancing. CHAIR
incredibly dense philosophical discussions of the Some of the reductions are organic. Remember Stephen H. Knitter
Geiger & Peters, Inc.
shows’ impact on the greater metaverse. And to be that a large portion of steel’s carbon footprint
VICE CHAIR
clear, I have no idea what all of that means. is purely based on its energy intensity—and as
Hugh J. McCaffrey
But if you can imagine the level of complexity the U.S. grid moves to more renewable energy,
Southern New Jersey Steel Co.
devoted to analyzing innocuous TV programming, we can expect a continuing decrease in carbon
SECRETARY/LEGAL COUNSEL
you can probably begin to grasp the complexity of footprint (by some estimates, the pivot to more Edward Seglias, Cohen Seglias
looking at a topic like sustainability. renewable energy alone will lead to around a Pallas Greenhall & Furman, PC
On its most basic level, we can equate sus- 41% reduction in carbon emissions from domestic PRESIDENT
tainability in design with net-zero carbon con- structural steel production). Charles J. Carter, SE, PE, PhD
struction. The wood industry folks are gods at But we’re also seeing a lot of other SENIOR VICE PRESIDENT
oversimplifying this equation. They conveniently technological improvements that will further reduce Scott Melnick
ignore the details and make overly broad general- steel’s environmental impact. We’re seeing steel SENIOR VICE PRESIDENT
izations—e.g., what happens with the 40% to 60% producers begin to build their own sustainable Mark W. Trimble, PE
of material left behind when trees are harvested, power sources next to their mills. We’re seeing VICE PRESIDENT
the environmental differences between not just two the incorporation of carbon-scrubbing equipment. Todd Alwood
different species of tree but also two different trees We’re seeing mills retaining most of their cooling VICE PRESIDENT
within the same species, what percentage of wood water in closed-loop systems, as well as looking Carly Hurd
products is actually obtained from sustainably man- at alternatives to water as a cooling source. We’re VICE PRESIDENT
aged forests, and what happens to wood after a seeing mills move away from natural gas to power Lawrence F. Kruth, PE
building reaches the end of its life. (Seriously, does their preheat furnaces. And much more. VICE PRESIDENT
anyone really believe that 30-year-old CLT panels In fact, all the domestic structural steel mills Mike Mospan
are going to be carefully demounted from exist- have made substantial commitments to reduce VICE PRESIDENT
ing buildings and somehow incorporated into new their carbon footprint. For example, you can read Brian Raff
construction?). about Nucor’s commitment to reducing its carbon
Editorial Advisory Panel
Likewise, you can achieve today a net-zero footprint by 35% by 2030—and how they’ll accom- Brandon Chavel, PE, PhD
carbon project using structural steel. The nation’s plish it—at nucor.com/greenhouse-gas-reduction- Michael Baker International
largest steel producer, Nucor, is happy to sell you target-strategy. You can read about Gerdau’s Nat Killpatrick
its Econiq-branded product. Using a combination efforts at www2.gerdau.com/climatechange Basden Steel
of carbon offsets and purchasing agreements for and SDI’s at stld.steeldynamics.com/valuing- Christina McCoy, SE
renewable energy, the company can designate its our-environment. (You can also read more about Oklahoma State University
product as net-zero carbon—all for a very modest sustainability and steel on page 54.) School of Architecture
premium. And if the demand exists, other mills can Today, American structural steel, thanks to its Allison Shenberger, PE
offer a similar product. 93% recycled content, is already an earth-friendly ruby+associates
And as a first step, products like Econiq are construction material. But that’s not good enough— Justin Smith, PE
Walter P Moore
great. Fortunately, the steel industry isn’t content and thankfully, the industry is investing both time
with this approach alone. Companies like Nucor and money to truly reach the goal of being a car- Advertising Sales
are committed to continuous reductions in their bon-neutral material. And since video speaks louder M.J. Mrvica Associates, Inc.
2 W Taunton Avenue
carbon footprint and are investing millions of than words, check out aisc.org/vr to see the mod- Berlin, NJ 08009
dollars every year to develop and implement ern steelmaking process, as well as videos of other 856.768.9360
improved solutions. steps in the structural steel supply chain. mjmrvica@mrvica.com
For decades, American steel (and remember, Address Changes and
the U.S. structural mill capacity in 2022 already Subscription Concerns
exceeds the demand for structural steel for Ameri- 312.670.2401
subscriptions@aisc.org
can building and bridge projects, and new mills
are under construction) has worked to truly reduce Scott Melnick Reprints
its carbon footprint. Currently, the major U.S. mills Editorial Director Kristin Hall
hall@aisc.org
6 | JUNE 2022
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steel interchange
If you’ve ever asked yourself “Why?” about something related to structural steel
design or construction, Modern Steel’s monthly Steel Interchange is for you!
Send your questions or comments to solutions@aisc.org.
Significant Load Reversal: Part 1
The Commentary on page 16.2-34 effect and, therefore, whether slip can be were pretensioned as required in Section
of the 2020 RCSC Specification for permitted or must be prevented. 4.2 of the RCSC Specification but still
Structural Joints Using High-Strength High-strength bolting began to be used designed as bearing connections, as is done
Bolts states: “Joints that are required around the 1950s. In my experience (both in AISC Design Guide 29: Vertical Bracing
to be slip-critical joints include: firsthand dating to the early-to-mid-1990s Connections—Analysis and Design, the Design
(2) Those cases where a slip of any and secondhand looking at calculations Examples associated with the AISC Steel
magnitude must be prevented, such and interacting with older engineers), it is Construction Manual, and, I believe, in all of
as in joints subject to significant load rare to see bracing connections designed the handbooks I have ever encountered that
reversal and joints between elements as slip-critical connections when standard address such conditions. Given the ubiquity
of built-up compression members in holes are used. Note that Section 4.3.1 of the practice, one might expect problems
which any slip could cause a reduction states that slip-critical joints are required to have occurred in service if the practice
of the flexural stiffness, which is for “joints that are subject to fatigue load was likely to result in problems. The lack
required for the stability of the with reversal of the loading direction.” of issues might then be taken as evidence
built-up member." The AISC Specification for Structural Steel that there will not be future problems.
Some engineers in our office have Buildings (AISC 360-16), in Section B3.11, It is possible that one could have lateral
taken that to mean slip-critical bolts are states: “Fatigue need not be considered for force-resisting system connections that
required for all lateral force-resisting seismic effects or for the effects of wind will see tension and compression for which
system connections that will see tension loading on typical building lateral force- “slip of any magnitude must be prevented”
and compression. Is this correct? resisting systems and building enclosure because “slip at the faying surfaces would
components.” At this point, there must be detrimental to the performance of the
No, it is up to the engineer of record be thousands of structures in which the structure.” But based on my experience,
to determine whether the load reversal connections subject to “significant load this would be unusual.
produces a significant or negligible reversal” due to wind or seismic loading Larry S. Muir, PE
Significant Load Reversal: Part 2
Section 4.2 of the RCSC Specification These seem to be referring to the The critical statement in the Commentary
states: “Pretensioned joints are same thing. Is this an error in the is: “Those cases where slip of any magnitude
required in the following applications: RCSC Specification? must be prevented…” For joints subjected
( 2 ) Jo i n t s t h a t a r e s u b j e c t t o to significant load reversal, the joint must be
significant load reversal.” However, No, it is not an error. Section 4.2 and the pretensioned. If, for that same joint, there is
the Commentary on page 16.2-34 Commentary you refer to do not address also enough concern about slip such that slip
states: “Joints that are required to be the same thing, and I believe they are using of any magnitude must be prevented, then the
slip-critical include: (2) Those cases the term “significant load reversal” in a joint should be designed as slip-critical. Note
where slip of any magnitude must be consistent manner. that this is consistent with the requirement in
prevented, such as in joints subject Significant load reversal means that the Section 4.3 in the RCSC Specification, which
to significant load reversal and load reverses direction in a manner that states: “Slip-critical joints are required in
joints between elements of built-up causes more than a negligible effect. When the following applications involving shear
compression members in which any this occurs, the RCSC Specification Section or combined shear and tension: (4) Joints
slip could cause a reduction of the 4.2 requires the joint to be pretensioned. in which slip at the faying surfaces would
flexural stiffness, which is required for The RCSC Specification does not require be detrimental to the performance of the
the stability of the built-up member.” the joint to be designed as slip-critical. structure.”
Larry S. Muir, PE
All mentioned AISC standards, unless noted otherwise, refer to the current version and are available at aisc.org/specifications,
AISC Design Guides are available at aisc.org/dg, and Engineering Journal articles can be found at aisc.org/ej.
Modern Steel Construction | 9
steel interchange
Galvanized High-Strength Bolts
Is it permissible to galvanize high-strength “Mechanical galvanizing of spline-end Table 2.1
bolts? twist-off and fixed matched bolting Group Designations for Bolts and
assemblies shall be performed only Matched Bolting Assemblies
Yes, this is addressed in the 2020 RCSC under the direction of the Manufacturer
Matched
Specification in Section 2.8.1: and as permitted by their respective Tensile
Group Bolts Bolting
“Group 120 and Group 144 bolting standards. Hot-dip galvanizing of Strength
Assemblies
components are permitted to be hot- spline-end matched bolting assemblies ASTM
dip or mechanically galvanized, except is not permitted.” Group F3125 ASTM F3125
120 ksi
that direct-tension indicators are only 120 Grade Grade F1852
“Hot-dip or mechanical galvanizing A325
permitted to be mechanically galvanized
of Group 150 heavy hex bolts or Group ASTM F3148
in compliance with ASTM F959.” 144 ksi —
Group 150 spline-end matched bolting 144 Grade 144
“Hot-dip galvanized bolting components assemblies is not permitted.” ASTM
shall meet the requirements of ASTM Group F3125 ASTM F3125
150 ksi
150 Grade Grade F2280
F2329. Mechanically galvanized bolting The “groups” referred to here are
A490
components shall meet the Class 55 defined in Table 2.1, which lists the
requirements of ASTM B695. All applicable bolt ASTM standards. The Jonathan Tavarez, PE
threaded components of the bolting Commentary in this section also provides
assembly shall be galvanized by the helpful guidance that you should review.
same process.”
Various Interaction Equations
When designing a single-plate shear Each of the interaction equations you to determine what is appropriate for
connection for combined axial, shear, mentioned is valid for its intended your situation.
and flexural loads, the 15th Edition AISC purposes. Different equations are used in AISC Manual Equation 9-1 is applicable
Steel Construction Manual recommends various situations in AISC publications. to the plastic strength of members and
using Equation 9-1. However, in AISC In many cases, more than one interaction connection elements with rectangular
Design Example II.A-17B, which looks equation is valid, and the equation is cross sections. The development of this
at a connection subjected to axial selected based on the author’s judgment. partially empirical equation is discussed in
and shear loading, an equation that is I have used all of these equations and the first quarter 2015 Engineering Journal
derived from Chapter H in the AISC several more in my connection design article “Plastic Strength of Connection
Specification for Structural Steel Buildings practice. The selection of an appropriate Elements.” This equation is limited to
(ANSI/AISC 360), in conjunction with interaction equation is dependent elements with low slenderness (where
AISC Manual Equation 10-5, is used. on several considerations, including buckling is prevented). As discussed in
Can you help me understand why the cross-sectional shape (I-shaped, the fourth quarter 2016 Engineering
different interaction equations are used T-shaped, rectangular, etc.), the stress Journal article “Stability of Rectangular
for similar load combinations? distribution on the cross section Connection Elements,” when stability is
2 4
(elastic, inelastic, plastic), the loading a design consideration, the interaction
Mr
+ Pr + Vr ≤ 1.0 (9-1) types (shear, axial, flexure, torsion), equations in the 2016 AISC Specification,
Mc Pc Vc and the slenderness for members that Section H1.1 are more appropriate.
Vr 2+ Mr 2≤ 1.0 (10-5) are subjected to compression stresses. Bo Dowswell, PE, PhD
Vc Mc Ultimately, you must use your judgment
Pr
+ Mrx + Mry ≤ 1.0 (H1-1b)
2Pc Mcx Mcy
Jonathan Taverez (taverez@aisc.org) is The opinions expressed in Steel Interchange do not
necessarily represent an official position of the American
AISC’s structural steel specialist in the Institute of Steel Construction and have not been reviewed.
New York City Market. Larry Muir and It is recognized that the design of structures is within the
scope and expertise of a competent licensed structural
Bo Dowswell, principal with ARC Steel Interchange is a forum to exchange useful and
engineer, architect or other licensed professional for the
practical professional ideas and information on all phases
International, LLC, are consultants to AISC. of steel building and bridge construction. Contact Steel
application of principles to a particular structure.
Interchange with questions or responses via AISC’s Steel The complete collection of Steel Interchange questions and
Solutions Center: 866.ASK.AISC | solutions@aisc.org answers is available online at www.modernsteel.com.
10 | JUNE 2022This month’s questions and answers were developed by Michael Desch, an AISC intern
steel quiz and current graduate student at the Illinois Institute of Technology. Thanks, Michael!
This month’s Steel Quiz explores the design considerations that impact the structural
design of hybrid steel-framed structures with mass-timber floors.
For guidance, you can consult the newly released AISC 5 What is the maximum joint tolerance for panel gaps
Design Guide 37: Hybrid Steel Frames with Wood Floors suggested by the design guide?
(available at aisc.org/dg). a. 1∕8 in. b. 3∕16 in. c. ¼ in. d. 3∕8 in.
1 Which of the following is a benefit of hybrid steel-timber 6 Which of the following is an actual difference between
building systems?
glue-laminated-timber (GLT) and cross-laminated-timber
a. Larger columns sizes c. Less prefabrication
(CLT) products?
b. Increased construction speed d. All of the above
a. Layer-to-layer bonding differs. Adhesives are used to
2 True or False: For hybrid construction where both the steel bond the layers of GLT, while CLT uses mechanical
structure and mass timber are exposed, intumescent paint fasteners (screws, nails, or dowels).
may be used when fire protection is required for the steel. b. The layer type differs. The plies of GLT are made of
many thin layers of wood veneer, while CLT is made
3 True or False: A 6-in.-thick five-ply CLT floor panel alone from plies of dimensional lumber.
can sufficiently isolate acoustic transmission for most office c. The orientation of each layer differs. GLT layers may be
and residential applications. oriented in parallel, while in CLT, every layer is oriented
4 True or False: Two key advantages of the steel framing in perpendicular to adjacent layers.
a hybrid system are that (1) the flexibility of the steel lateral d. The fabrication location differs. GLT products are
force-resisting system (LFRS) can minimize the impact of the generally fabricated on-site, while CLT products are
lateral system on the building architecture and (2) using a usually prefabricated in factories
steel LFRS provides a proven path to code compliance.
TURN TO PAGE 14 FOR THE ANSWERS
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Everyone is welcome to submit questions and answers for the Steel Quiz.
If you are interested in submitting one question or an entire quiz, contact
steel quiz ANSWERS AISC’s Steel Solutions Center at 866.ASK.AISC or solutions@aisc.org.
1 b. Increased construction speed. reduced column sizes, lightweight exposed to fire. More information on
There are many advantages of construction, prefabrication, increased designing fire protection for hybrid
using a hybrid steel-timber build- speed of construction, and more. You systems can be found in Chapter 3 of
ing system. Both materials can can find more information on the ben- Design Guide 37.
play to their respective strengths efits of hybrid steel-timber systems in
Section 2.1 of Design Guide 37.
3 False. As discussed in Section 4.2 of
to provide benefits over typical
the Design Guide, a 6-in.-thick five-
steel or timber structures. These
2 True. Intumescent paint protects ply CLT panel will typically provide a
advantages include aesthetics, sus-
the underlying steel by charring and sound transmission class (STC) rating
tainability, long-span capabilities,
expanding to insulate the member when of about 40 and an impact insula-
tion class (IIC) rating in the mid-20s.
These ratings are insufficient for most
applications, with the International
Building Code (IBC) recommending
a minimum rating of 50 for both mea-
sures. Additional topping materials
can be used to improve the acoustic
performance of the floor assembly.
4 True. Braced frames and moment
frames are the most commonly
used LFRS. However, any steel LFRS
allowed by the authority having
jurisdiction can be used in a hybrid
project. In high-seismic areas, more
ductile LFRS are used in accordance
with the AISC Seismic Provisions for
Structural Steel Buildings (ANSI/AISC
341, aisc.org/specifications). CLT
panels can help reduce the mass of
the building, which in turn reduces
the seismic forces. More informa-
tion on designing lateral systems for
hybrid steel and mass timber floor
projects can be found in Section 6.2
of the Design Guide.
5 b. 3∕16 in. As discussed in Section 7.3
of the Design Guide, no standard
code of practice exists for erection
tolerances of mass timber construc-
tion. Therefore, the authors proposed
several erection tolerances to serve
as reasonable starting points when
discussing specific tolerance require-
ments with the contracting team.
6 c. The orientation of each layer
differs. GLT, due to the paral-
lel orientation of each ply and the
anisotropic nature of wood, offers
the most strength along a single axis,
so it is useful for beams, columns,
and slabs in one-way bending. CLT,
due to the alternating orientations of
each layer, provides strength in mul-
tiple directions. It is useful for walls,
floors, and roofs and has two-way
span capabilities. More information
on GLT, CLT, and other mass timber
products can be found in Section 1.2
of Design Guide 37.
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Are You Properly Specifying Materials?
BY JONATHAN TAVAREZ, PE
Learn what's new in the world of structural steel materials.
WITH THE UPCOMING publication of the ments but rather guidance (see the 65, or QST 70. Atmospheric corrosion
16th edition AISC Steel Construction Man- article “Says Who?” in the August 2013 resistance (weathering characteristics) can
ual comes an opportunity to verify that you issue, available in the Archives section be obtained by specifying ASTM A588
are correctly specifying materials. at www.modernsteel.com). AISC rou- for building construction or ASTM A709
As we know, ASTM specifications tinely surveys structural steel fabricators and Grade 50W and QST grades for bridge
undergo periodic revisions, and new ones producers to determine the most common construction. These and other material
come into existence. The design and con- and preferred material specifications for specifications applicable to S-shapes and
struction process is significantly simpli- various shapes. You may still be able to spec- M-shapes are shown in Table 2-4.
fied through the reference of appropriate ify something that does not align with these Channels. Both Standard Channels and
ASTM specifications because they allow recommendations, but this should only be Miscellaneous Channels (MC) are most
you to define all the relevant characteristics done based on engineering judgment and commonly available as ASTM A992. Some
of a specified product. after discussing with the fabricator. smaller channels less than 8 in. may still
However, with dozens of ASTM speci- only be available as A36 material. Please
fications applicable to steel construction Structural Shapes confirm with a local fabricator before spec-
alone, keeping the standard designations Let’s start with structural shapes, sum- ifying ASTM A992 material for channels
used in contracts current can be challeng- marized in Table 2-4. smaller than 8 in. Atmospheric corrosion
ing. Here, we’ll provide an updated sum- W-shapes. The preferred material resistance (weathering characteristics) can
mary of the most common ASTM speci- specification for W-shapes is ASTM A992 be obtained by specifying ASTM A588 for
fications used in steel building design and (Fy = 50 ksi, Fu = 65 ksi). The availability building construction. Also, refer to Table
construction, including standards for struc- and cost-effectiveness of W-shapes in 2-4 for the preferred material for channels.
tural shapes, plate products, fastening prod- grades other than ASTM A992 should be HP-shapes. The preferred material speci-
ucts, and more. This information is based confirmed before specifying. W-shapes of fication for HP shapes is ASTM A572 Grade
on similar information in the new version limited sizes with higher yield and ten- 50 (Fy = 50 ksi, Fu = 65 ksi); other grades’
of the Manual. Another useful AISC publi- sile strength can be obtained by specify- availability and cost-effectiveness should
cation is Selected ASTM Standards for Steel ing ASTM A529 Grade 55, ASTM A572 be confirmed prior to specification. HP-
Construction including Structural Stainless Grades 55, 60, and 65, ASTM A913 Grades shapes with atmospheric corrosion resistance
Steel, which provides a compilation of 98 60, 65, 70, and 80, or A709 Grades QST (weathering characteristics) can be obtained
structural and stainless steel-related ASTM 50S, QST 65, and QST 70. W-shapes with by specifying ASTM A588 Grade 50. These
standards. Selected ASTM Standards is pres- atmospheric corrosion resistance (weath- and other material specifications applicable
ently available at aisc.org/publications. ering characteristics) can be obtained by to HP-shapes are shown in Table 2-4.
The AISC 16th Edition Steel Construction specifying ASTM A588 for building con- Angles. The preferred material specifi-
Manual will be available in mid-2023. struction or ASTM A709 Grade 50W and cation for angles is ASTM A572 Grade 50.
All ASTM standard specifications have QST grades for bridge construction. These Angles may be available in other strength, but
a typical format. Of course, the chemical and other material specifications applicable the preferred material is shown in Table 2-4.
and mechanical property requirements are to W-shapes are shown in Table 2-4. Structural tees. Structural tees are split
essential, but an often-overlooked section S-shapes and M-shapes. The pre- from W-, M- and S-shapes to make WT-,
is “Ordering Requirements.” This section ferred material specification for these MT- and ST-shapes, respectively. For the
lists the items necessary to list when pur- shapes is now ASTM A572 Grade 50 preferred material specifications and other
chasing materials to ensure that you obtain (Fy = 50 ksi, Fu = 65 ksi). The availability suitable material specifications for struc-
the product required. Some standards also and cost-effectiveness of S-shapes and tural tees, refer to the preceding sections
depend heavily on other ASTM standards, M-shapes in grades other than those listed on W-, M- or S-shapes, as appropriate.
with an example being the reliance on should be confirmed prior to their speci- Rectangular (and square) HSS. The
ASTM A6 for common delivery require- fication. S-shapes and M-shapes with a preferred material specification for rectan-
ments. Some standards also contain help- higher yield and tensile strength can be gular hollow structural sections (HSS) is
ful information in notes and Annexes that obtained by specifying ASTM A529 Grade ASTM A500 Grade C (Fy = 50 ksi, Fu = 62
should be reviewed as well. 55, ASTM A572 Grades 55, 60, and 65, ksi). Two notable options for HSS are A1065
Note that this article, along with the ASTM A913 Grades 60, 65, 70, and 80, or, and A1085. A1085 (Fy = 50 ksi, Fu = 65 ksi)
Manual, should not be taken as require- for bridges, A709 Grades QST 50S, QST provides actual wall thickness and tighter
16 | JUNE 2022steelwise
corner radii tolerances for design. Additional
benefits include a maximum yield stress of Table 2-4
70 ksi for A1085 and a defined standard for Applicable ASTM Specifications for Various Structural Shapes
Charpy V-notch material toughness. The Applicable Shape Series
availability and cost-effectiveness of rectan-
HSS
gular HSS in grades other than ASTM A500 Fy Fu
Yield Tensile
Round
Grade C should be confirmed prior to their
Rect.
Stressa Stressa
Pipe
ASTM
specification. Since A500 Grade C require- Steel Type Designation (ksi) (ksi) W M S HP C MC L
ments also meet the requirements of A500 A36 36 58–80b
Grade B, it is likely that you will receive A53 Gr. B 35 60
A500 Grade C material regardless of what Gr. B 46 58
you specify. It is, therefore, best to specify A500 Gr. C 50 62
Grade C to take advantage of the increased Gr. D 36 58
design strength. Rectangular HSS with
A501h Gr. B 46 65
atmospheric resistance (weathering char- Carbon
Gr. 50 50 65–100
acteristics) can be obtained by specifying A529c
Gr. 55 55 70–100
ASTM A847 or A1065 Grade 50W. These
A709 Gr. 36 36 58–80b
and other material specifications applicable
Gr. 36 36–52 58
to rectangular HSS are shown in Table 2-4. A1043d,g
Gr. 50 50–65 65
Round HSS. The preferred material
specification for round HSS is ASTM A500 A1085 Gr. A 50-70 65
Grade C (Fy = 50 ksi, Fu = 62 ksi). This is Gr. 42 42 60
a significant change from the 46-ksi yield Gr. 50 50 65
stress that was previously the standard for A572i Gr. 55 55 70
round HSS specified as A500 Grade C. This Gr. 60e 60 75
change occurred in the revision to ASTM Gr. 65e 65 80
A500 Grade C in 2021. Note that A1085 Gr. Iag, Ib
50f 70f
(Fy = 50 ksi, Fu = 65 ksi) may also be speci- A618h & II
fied for round HSS members for actual wall Gr. III 50 65
thickness. The availability and cost-effec- High-Strength Gr. 50 50 65
tiveness of round HSS in grades other than Low-Alloy A709 Gr. 50S 50–65 65
ASTM A500 Grade C should be confirmed Gr. 50W 50 70
prior to specification. Generally speaking, Gr. 50 50 65
only round HSS with the same cross-sec- Gr. 60 60 75
tional dimensions as steel pipe are stocked A913 Gr. 65 65 80
and readily available (see the “12 Tidbits” Gr. 70 70 90
sidebar for further information). Round Gr. 80 80 95
HSS with atmospheric corrosion resistance A992 50–60 65
(weathering characteristics) can be obtained A1065g Gr. 50 50 60
by specifying ASTM A847. These and other Corrosion- Gr. QST 50 50 65
material specifications applicable to round Resistant Gr. QST 50S 50–60 65
HSS are shown in Table 2-4. Quenched A709
and Tempered Gr. QST 65 65 80
Steel pipe. The Manual lists ASTM
Low-Alloy Gr. QST 70 70 90
A53 Grade B (Fy = 35 ksi, Fu = 60 ksi) as
Corrosion- A588 50 70
the preferred material specification for steel Resistant
A847 50 70
pipe used in structural frames—however, High-Strength
Low-Alloy A1065g Gr. 50W 50 70
the following considerations should be
addressed first. Round ASTM A500 Grade
Note: Referenced standards in Table 2-4 are intended to be the
C can be specified using pipe dimensions = Preferred material
versions specified in AISC Specification Section A2.
specification.
instead of A53 to take advantage of the a
Minimum, unless a range is shown.
b
For wide-flange shapes with flange thicknesses over 3 in.,
increased strength. A53 pipes need to = Other applicable
material only the minimum of 58 ksi applies.
be pressure tested, which results in an c
For shapes with a flange or leg thickness less than or equal to
specification,
unnecessarily increased overall cost for the availability of d
1½ in. only.
For shape profiles with a flange width of 6 in. or greater.
less strength than what could have been which should be e
For shapes with a flange or leg thickness less than or equal
obtained if round A500 Grade C was confirmed prior to 2 in. only.
to specification. f
specified. Additionally, regional availability Minimum applies for walls nominally ¾-in.-thick and under. For wall
thickness over ¾ in. and up to 1½ in., Fy = 46 ksi and Fu = 67 ksi.
may play a factor, so be sure to contact your = Material g This specification is not a prequalified base metal per AWS
fabricator. See the sidebar “12 Tidbits” for specification
D1.1/D1.1M:2020.
does not apply. h ERW or seamless HSS only.
further information. i Type 1, 2, or 3 only.
Modern Steel Construction | 17steelwise
Table 2-5 Plate Products
Applicable ASTM Specifications for Plates and Bars Next, let’s look at steel plate, which
is summarized in Table 2-5.
Plates and Bars, thickness, t, in.
Structural plates. ASTM A36 and
over 0.75 to 1.25
A572 Grade 50 should be readily avail-
over 1.25 to 1.5
able for main member or weldment
over 1.5 to 2
over 2 to 2.5
over 2.5 to 4
over 4 to 5
over 5 to 6
over 6 to 8
design. It is more common for plate
Fy Fu
material to ASTM A572 Grade 50 (Fy
to 0.75
Yield Tensile
over 8
Steel ASTM Stressa Stressa = 50 ksi, Fu = 65 ksi). If plate mate-
Type Designation (ksi) (ksi) rial is specified as A36 (Fy = 36 ksi, Fu
32 58–80 = 58 ksi), it is very likely that you will
Connecting
58–80 be receiving an A572 Grade 50 plate
A36 elements
36 since the mechanical properties of A572
All other
58–80 Grade 50 meets the same requirements
applications
Carbon d of A36. One caution when specifying
Gr. C 30 55–75
A238e d
plates over 4 in. thick. A572 Grade 50
Gr. D 33 60–80
material is not commonly available for
Gr. 50 50 65–100 b b b b b
A529 plates over 4 in. thick. When ASTM
55 70–100 c c c c c
Gr. 55 A36 is specified for plates over 4 in.
A709 Gr. 36 36 58–80 thick, the yield strength drops to 32 ksi
Gr. 42 42 60 rather than 36 ksi. One major change
Gr. 50i 50 65 in the new Manual is the preference
A572h Gr. 55 55 70 of material for connecting elements is
now ASTM A572 Grade 50. This does
Gr. 60j 60 75
not prohibit the use of A36, but it rec-
Gr. 65 65 80
ognizes the prevalence of 50 ksi mate-
A709 Gr. 50 50 65
High- rial in the supply chain. ASTM A36 is
Strength Gr. 36 36–52 58 included as the preferred material for
e
Low-Alloy A1043 50–65 65
Gr. 50 connecting elements with thicknesses of
Gr. 50 50 65 4 in. through 8 in. The availability and
Gr. 60 60 75 cost-effectiveness of structural plates in
A1066 Gr. 65 65 80 f grades other than these should be con-
Gr. 70 70 85 firmed prior to their specification. Note
80 90 g that thickness ranges are also different
Gr. 80
e
for other grades, as shown in Table
Corrosion- 42 63
Resistant 2-5. Structural plates with higher yield
A588 46e 67
High- and tensile strength can be obtained by
Strength 50 70 specifying ASTM A572 Grade 55, 60,
Quenched
90 100–130 or 65; ASTM A529 Grade 55; ASTM
and
A514e A1066 Grade 60, 65, 70, or 80; or
Tempered
Alloy 100 110–130 ASTM A514 Grade 90 or 100. Struc-
Gr. 50W 50 70 tural plates with atmospheric corrosion
Corrosion-
Resistant 50 70
resistance (weathering characteristics)
Gr. HPS 50W
Quenched can be obtained by specifying ASTM
A709 Gr. HPS 70W 70 85–110
and A588 Grade 42, 46, or 50. These and
Tempered Gr. HPS 90 100–130
other material specifications applicable
Low-Alloy 100We 100 110–130 to structural plates are shown in Table
Note: Referenced standards in Table 2-5 are intended to be the
2-5. For significant orders, ASTM A709
= Preferred material
specification. versions specified in AISC Specification Section A2. HPS 50 or70 can be considered.
a Minimum, unless a range is shown. Structural bars. The preceding
= Other applicable b Applicable for plates to 1 in. thickness and bars to 3½ in. thickness.
material c Applicable for plates to 1 in. thickness and bars to 3 in. thickness. comments for structural plates apply
specification, d Thickness is not limited to 2 in. in ASTM A283 and thicker plates equally to structural bars, though note
the availability of may be obtained but availability should be confirmed. that ASTM A514 is not applicable.
which should be e This specification is not a prequalified base metal per
AWS D1.1/D1.1M:2020. While frequently falling in the same
confirmed prior
to specification. f Applicable for plates to 3 in. thickness. size ranges as plates, bars are a separate
g Applicable for plates to 1 in. thickness. classification and are generally available
= Material h Type 1, 2, or 3 only as given in Specification Table A3.1
specification i Round bars up to and including 11 in. diameter are permitted. in widths up to 8 in. The terminology
does not apply. j Round bars up to and including 3½ in. diameter are permitted. section in the ASTM A6 Standard (see
18 | JUNE 2022steelwise
Selected ASTM Standards for Steel Construc- maximum carbon by heat analysis, and standard with many types and grades; the
tion including Structural Stainless Steel) pro- without specified mechanical properties.” structural steel type is designated “SS” and
vides thickness, width, and length defini- Alternatively, if a defined strength level is the standards provide for grades from 25
tions to differentiate between steel plates desired, ASTM A786 raised-pattern floor or 30 to 80. High-strength low-alloy and
and bars. plate can be ordered to a specific plate high-strength low-alloy with improved
Raised-Pattern Floor Plates. ASTM material specification, such as ASTM A36, formability are designated as HSLAS and
A786 is the standard specification for A572, or A588; see ASTM A786 Sections HSLAS-F, respectively, and may also be
rolled steel floor plates. As strength 5.1.3, 7.1, and 8.1. specified if needed. When using shims and
considerations seldom control the floor- Sheet and Strip. Sheet and strip prod- similar products, note that 3∕16 in. is the
plate design, ASTM A786 “commercial ucts, which are generally thinner than minimum thickness to specify and receive
grade” is commonly specified. In those structural plate and bar products, are pro- a mill test report conforming to an ASTM
cases, per ASTM A786-15, Section 5.1.3, duced to such ASTM specifications as A606, standard material. Availability should be
“The product will be supplied with 0.33% A1008, or A1011. This is an “umbrella” checked before specifying the grade.
12 Important Tidbits
Here are a dozen points to consider HSS6.000×0.250 is an HSS-only product to embarrass you by pointing out that
when specifying materials for your next and may require a mill-order quantity. you’ve specified a product that does
project. 5. Properly designate your HSS. not come in the length you likely speci-
1. When in doubt, check it out. A round HSS is designated by out- fied—or as a hooked or longer-threaded
Have questions about availability? Call side diameter and wall thickness, each rod. Use ASTM F1554, which covers
a fabricator or contact the AISC Steel expressed to three decimal places—e.g., hooked, headed, and threaded/nutted
Solutions Center (solutions@aisc.org; HSS6.625×0.28. A square or rectangular rods in three strength grades and even
866.ASK.AISC). Either one can keep you HSS is designated by nominal outside has only slightly greater tensile strength
swimming in available steel. Also, visit dimensions and wall thickness, each than A325 when specified as Grade 105.
aisc.org/aisc-membership to search for in rational numbers—e.g., HSS4×4×3∕8. ASTM F3125 Grade A325 has a tensile
member providers. Rectangular HSS with even dimensions strength of 120 ksi, while ASTM F1554
2. Times change. When ASTM A992 for sides—e.g., HSS6×4×5∕16—is more Grade 105 has a tensile strength of 125–
was initially introduced, only W-shapes readily available than odd-numbered 150 ksi.
were covered. A later revision to this dimensions—e.g., HSS5×3×3∕8. 8. Have all the information at your
ASTM standard expanded its scope to 6. Properly designate your steel fingertips. More extensive information
include other hot-rolled structural cross pipes. Use nominal pipe size (NPS) des- can be found in the 16th Edition Man-
sections (channels, angles, S-shapes, ignation through NPS 12—e.g., Pipe 5 ual (available in 2023) and the Selected
etc.), allowing them to be made to ASTM Std., Pipe 5 x-strong, or Pipe 5 xx-strong. ASTM Standards for Steel Construction
A992. Nevertheless, A992 still is not Note that this notation has commonly including Structural Stainless Steel (avail-
common in shapes other than W-shapes been abbreviated for the examples able at aisc.org/publications).
and channels. given: P5, PX5, and PXX5, respectively. 9. Remember to specify the alter-
3. Round HSS ≠ steel pipe. Know Above NPS 12, use the format “Pipe” nate core location CVN requirement
the difference between ASTM A500 and followed by nominal diameter × nominal when you have heavy shapes or plates
ASTM A53. While ASTM A53 (Fy = 35 ksi) wall thickness, each expressed to three with CJP groove welds and subject to
is the listed preferred material for pipes, decimal places—e.g., NPS 14 Standard tension; see AISC Specification Sections
ASTM A500 (Fy = 50 ksi for Grade C) is designated Pipe 14.000×0.375. The A3.1c and A3.1d for further information.
can be specified instead of using pipe latter format also applies to any steel 10. When specifying weathering
dimensions. See Tidbit 4 to learn how to pipe size smaller than NPS 12 that does steel plates or bars, think ASTM A588
specify pipe dimensions for round HSS. not have an NPS size. first. ASTM A242 is no longer commonly
4. Generally speaking, only round 7. Don’t confuse anchor rods with used and has been removed from Table
HSS with the same cross-sectional structural bolts. Do not specify your 2-5 in the Manual.
dimensions as steel pipe are stocked anchor rods as ASTM F3125 Grade A325 11. Use the MC12×14.3 for stair
and available. Avoid specifying a round or A490. The ASTM F3125 standard cov- stringers. Due to its flange width, the
HSS with a cross section that does ers headed bolts, with limited thread handrail pipe sizes will fit, as will the fillet
not match up to one of the steel pipe length, generally available only up to welds used to connect them to this new
cross sections. This is much easier than 8 in. in length and governed by provi- channel with a wider flange.
it sounds; use round HSS with non- sions for steel-to-steel structural joints 12. When in doubt, check it out
zero numbers after the decimal point. only. You say you’ve always specified and ask your fabricator. Oh wait, this
For example, HSS6.625×0.28 has the your anchorage devices this way and it’s is number 1; well, it’s important enough
same cross section as a Pipe 6 Std. never been a problem? Well, the reality that it warrants being the first and last
And it will generally be available, while is that your fabricator has been nice not consideration.
Modern Steel Construction | 19steelwise
Fastening Products Specification for Structural Steel Buildings for anchor rods are usually larger than
Next, let’s explore fasteners, summa- (ANSI/AISC 360, aisc.org/specifications) those for steel-to-steel structural bolting
rized in Table 2-6. to use other material specifications in applications. AISC Manual Table 14-2 pro-
High-strength bolts. The umbrella steel-to-steel bolting applications, the use vides recommended hole sizes that corre-
bolt standard ASTM F3125 includes grades of materials besides those identified in this late with anchor rod placement tolerances
that were previously manufactured under article is relatively rare. from ACI 117. Accordingly, washers used
the standards ASTM A325, A490, F1852, Nuts. The preferred material specifica- in such applications generally must be
and F2280 for high-strength bolts in steel- tion for heavy-hex nuts is ASTM A563. The larger and require design consideration for
to-steel connections. Under the umbrella appropriate grade and finish for steel-to- proper force transfer, particularly when the
standard F3125, the previous ASTM stan- steel structural bolting applications are sum- anchorage is subject to tension. Table 14-2
dard designations become grades—i.e., marized in Section 2.3 of the 2020 RCSC is revised to reflect different material thick-
Grade A325 and A490 and Grade F1852 Specification for Structural Joints Using High- nesses for Grade 36, 55, and 105 anchor
and F2280. A325 and A490 are hex-headed Strength Bolts (aisc.org/specifications). If its rods. Such anchor rod washers are generally
bolts, while F1852 and F2280 are twist-off availability can be confirmed prior to specifi- made from rectangular plate or bar material.
tension-controlled bolts. Additionally, the cation, ASTM A194 Grade 2H nuts are per- Compressible-washer-type direct-
bolts were previously grouped by strength mitted as an alternative, as indicated in Sec- tension indicators. When bolted joints are
groups: Groups A (120 ksi), B (150 ksi), and tion 2.3.2 of the RCSC Specification. While specified as pretensioned or slip-critical and
C (200 ksi). Group C bolts were ASTM RCSC (Research Council on Structural the direct-tension-indicator pretensioning
F3043 or F3111 bolts. An additional bolt Connections) is the authority on the use of method is used, ASTM F959 compressible-
was added to the AISC Specification in 2022. nuts, Table 2 in the ASTM F3125 specifica- washer-type direct-tension indicators can
The new bolt standard ASTM F3148, with tion may have more up-to-date information be specified. Type 325 is used with ASTM
a tensile strength of 144 ksi, is introduced as and should be checked. F3125 Grade A325 or F1852 assemblies,
an applicable material for spline drive bolts Washers for structural bolts. The pre- and Type 490 is used with ASTM F3125
where the spline is used to pretension the ferred material specification for hardened Grade A490 or F2280 assemblies. ASTM
bolt, but it does not twist off. steel washers is ASTM F436. This speci- F3148 bolts are pretensioned to the same
To more clearly designate these bolts, the fication provides for both flat and beveled tension as Group 150 bolts (Grade A490),
previous Group letters were replaced by the washers. An “extra thick” option is available so the A490 DTIs should be used for this
material strength designations—i.e., Groups for the cases in RCSC Specification Table 6.1 application if DTIs are required. The use of
120, 144, 150, and 200. Type 1 is the most that require a special 5∕16 -in. thickness (when these devices must conform to the require-
commonly specified (medium-carbon steel). oversized or slotted holes are used in the ments in the RCSC Specification, which pro-
When atmospheric corrosion resistance outer ply of a steel-to-steel structural joint). vides detailed requirements for preinstal-
is desired, Type 3 can be specified. While Washers for anchor rods. In base lation verification (Section 7), installation
it is still formally permitted by the AISC plate applications, anchor rods’ hole sizes (Section 8), and inspection (Section 9).
New Things low alloy steel flux cored arc welding also be obtained and are discussed
Here’s a list of recent developments to electrodes. This standard is currently in the article “Larger Hollow Struc-
help guide your material specifications. present in D1.1:2020, but it has since tural Sections” in the November 2011
• Several new W, WT, and HSS shapes been withdrawn, with the two previous issue (www.modernsteel.com). This
are introduced in the 16th edition Man- standards remaining as the applicable includes a discussion of ASTM A1065
ual and are listed below: specifications. shapes produced by forming two chan-
– New W Shapes: W44×408, • A new bolt standard, ASTM F3148, is nels and welding them together.
W44×368, W36×387, W36×350, introduced and is meant to provide a • A channel especially for stair string-
W36×318, W36×286 strength between that of F3125 Grade ers. The MC12×14.3 that was recently
– New WT Shapes: WT22×204, A325 and A490, hoping to supersede added to ASTM A6 was conceived as
WT22×184, WT18×193.5, them both in the future. ASTM F3148 a stair stringer. It has a 21∕8-in. flange
WT18×175, WT18×159, WT18×143 bolts are also able to be mechanically width, wide enough to accept the stan-
– For brevity, the entire list is not galvanized. dard handrail pipe size and fillet weld
included here but note that there • Larger HSS. Until recently, ASTM around it. No more crimping the pipe
are 16 new square HSS shapes, A500 HSS was limited to 7∕8-in. thick- or goobering the weld!
130 new rectangular HSS shapes, ness and 88-in. perimeter. It now per- • Bigger HP-shapes. While not recently
and 64 new round HSS shapes. mits HSS to 1-in. thickness and 88-in. added to ASTM A6, the HP18 and HP16
• It should be noted that the AWS A5.36 perimeter. While the standards permit series shapes provide for even higher
standard was previously introduced these larger sizes, they are not currently pile strengths. Like all HP shapes, they
with the intention of combining A5.20 made in the U.S.; availability should be have thicker webs (tw = tf) and may help
and A5.29 into a single specifica- checked. HSS with sizes that exceed eliminate the need for stiffeners and
tion covering both carbon steel and ASTM A500’s 88-in. periphery limit can doublers when used as columns.
20 | JUNE 2022steelwise
Anchor rods. The preferred material
specification for anchor rods is ASTM Table 2-6
F1554, which covers hooked, headed, Applicable ASTM Specifications for Various Types of Structural Fasteners
threaded, and nutted anchor rods in two Bolts Anchor
Washers
strength grades: 36, 55, and 105. ASTM High-Strength Rods
F1554 Grade 55 is most commonly speci-
Threaded & Nutted
fied, although grades 36 and 105 are gener-
Tension Control
Tension Control
Threaded Rods
Common Bolts
Direct-Tension
ally available. Note that per Section 6.4 in
Twist-off-type
Conventional
ASTM F1554, when Grade 36 is ordered, Fy
Fixed-end
Hardened
Min. Fu
Indicator
the supplier may substitute weldable Grade
Hooked
Headed
Yield Tensile
55 at their discretion. ASTM F1554 Grade
Plain
Nuts
ASTM Stress Stressa Diameter
36 may be welded as is, and Grade 55 may Designation (ksi) (ksi) Range (in.)
be welded if ordered with Supplement S1; Gr. A325d – 120 0.5 to 1.5
ASTM F3125
this is the more common approach when Gr. F1852d – 120 0.5 to 1.5
welding is required. Grade 105 may not be Gr. A490d – 150 0.5 to 1.5
welded, as the heat will detrimentally affect Gr. F2280d – 150 0.5 to 1.5
performance. Several other ASTM specifi- F3111 – 200–215 1 to 1.25
cations may also be used. ASTM A36, A193, F3043 – 200–215 1 to 1.25
A307, A354, A449, A572, A588, and A687 F3148d – 144 0.5 to 1.25
can be specified for applications involving A194 Gr. 2H – – 0.25 to 4
rods that are not headed. All except A572 A563 – – 0.25 to 4
and A588 can be specified for applications F436 – – 0.25 to 4b
involving headed rods. F844 – – any
Threaded rods. The preferred mate- – 0.5 to 1.5b
F959 –
rial specification for threaded rods, whether
A36 36 58–80 to 15
provided with plain or upset ends, is ASTM
105 125 to 2.5
A36. Other material specifications that can
A193 Gr. B7 95 115 over 2.5 to 4
be specified include ASTM A193, A307,
75 100 over 4 to 7
A354, A449, A572, A588, and F1554. Note
that ASTM A354 Grade BC and A449 are A307 Gr. A – 60 0.25 to 4
125 0.25 to 2.5 e e
permitted to be used for bolts when the Gr. BC
109
A354
e e
size required is outside the range of ASTM 99 115 over 2.5 to 4
F3125 Grade A325. ASTM A354 Grade Gr. BD 130 150–173 0.25 to 4 e e
BD is permitted when the size required is 92 120 0.25 to 1 e e
outside the range of ASTM F3125 Grade A449d 81 105 over 1 to 1.5 e e
A490. These standards are material stan- 58 90 1.75 to 3 e e
dards, not bolt standards, so the desired Gr. 42 42 60 to 6
dimensions must be specified as per ANSI Gr. 50 50 65 to 4c
ASME B18.2.6 heavy hex class 2A.
A572
Gr. 55 55 70 to 2.5
Shear stud connectors. Shear studs Gr. 60 60 75 to 3.5
are specified as given in AWS D1.1 Clause Gr. 65 65 80 to 2
9, with material as required in Clause
50 70 to 4
9.2.6. Type B is usual, and the correspond-
A588 46 67 over 4 to 5
ing mechanical requirements are stated
42 63 over 5 to 8
in AWS D1.1 Table 9.1 (Fy = 51 ksi, Fu =
Gr. 36 36 58–80 0.25 to 4
65 ksi). When ordering, remember to add
F1554
Gr. 55 55 75–95 0.25 to 4
the required length by the amount of the
Gr. 105 105 125–150 0.25 to 3
“melt-off,” which depends on the number of
deck plies the stud is shot through.
Filler metal. AWS provides specifica- = Preferred material Note: Referenced standards in Table 2-6 are intended to be the
specification. versions specified in AISC Specification Section A2.
tions for filler metals in the A5 series of – Indicates that a value is not specified in the material specification.
specifications. Typically, there are two filler = Other applicable a Minimum unless a range is shown or maximum (max.)
metal specifications for each process: carbon material specification, is indicated.
the availability of b For use with fasteners with diameter range given.
steel for strengths up to E70 and low alloy which should be c ASTM A572 permits rod diameters up to 11 in., but practicality
for higher strengths or other properties such confirmed prior to of threading should be confirmed before specification.
d When atmospheric corrosion resistance is desired,
as weathering. These specifications provide specification.
Type 3 can be specified.
chemical composition requirements for the = Material specification e See AISC Specification Section J3.2 for limitations
filler metals and tensile property and CVN does not apply. on use of ASTM A449, A354 Gr. BC and A354 Gr. BD.
Modern Steel Construction | 21You can also read
