January 2022 - American Institute of Steel Construction
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January 2022
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January 2022
40
columns
steelwise
16 A New Shine on Steel Design
BY NANCY BADDOO, CENG, AND
MARK HOLLAND, PE
A look at the new AISC Specification for
Structural Stainless Steel.
field notes
20 By the Book
INTERVIEW BY GEOFF WEISENBERGER
As one of AISC’s longest-tenured employees,
Cindi Duncan has wrangled countless
committee members to keep publications on
track and on schedule.
business issues
in every issue 22 Looking Ahead
A group of construction professionals
departments
ponders the future of the industry and what
6 EDITOR’S NOTE can be done to ensure it’s a bright one.
9 STEEL INTERCHANGE
12 STEEL QUIZ
61 NEW PRODUCTS resources
62 NEWS & EVENTS 65 ADVERTISER INDEX
66 STRUCTURALLY SOUND 65 MARKETPLACE & EMPLOYMENT
features conference preview
26 Early to Rise
BY JIM FOREMAN AND WADE LEWIS
40 Building for the Future
BY BEN LOCKHART
54 Of Codes and Contracts
BY JASON COPLEY, ESQ, AND
For a new Denver hospital, early A general contractor known for self- MATTHEW SKAROFF, ESQ
coordination allowed for mill order and performing concrete work looks to steel to Tips for understanding the interplay between
steel detailing packages to be issued prior to frame its new headquarters building in Salt contracts and the AISC Code of Standard Practice.
construction documents. The result? Lake City.
A faster project. 56 Plan the Work, Work the Plan
BY BILL BORCH
48 Texas-Sized Steel Thoughts on how to improve erection
32 Elevating Engineering
BY ANGELA FANTE, PE
BY GEORGE R. BATCHA, IV, AND
MICHAEL T. KEMPFERT
planning and execution.
The University of Rhode Island’s new A steel producer for which sizable facilities
engineering building was designed to are the norm goes bigger than ever with its 59 Avoiding Surprises
BY BRUCE F. BROTHERSEN, PE
instigate interdisciplinary interaction. new sheet mill in Texas.
Notes on delegated design and the role of the
design professional of record.
ON THE COVER: Steel bracing is on full display at the the University of Rhode Island’s Fascitelli Center, p. 32. (Photo: James Ewing)
MODERN STEEL CONSTRUCTION (Volume 62, Number 1) 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 | JANUARY 2022
editor’s note
Editorial Offices
130 E Randolph St, Ste 2000
Chicago, IL 60601
Let’s talk about 312.670.2400
fried chicken for a minute. Editorial Contacts
EDITOR AND PUBLISHER
Scott Melnick
312.804.1535
I live in Chicago and commute melnick@aisc.org
to work via train. My local train SENIOR EDITOR
Geoff Weisenberger
station is right across the 312.493.7694
weisenberger@aisc.org
street from a Popeyes. DIRECTOR OF PUBLICATIONS
Keith A. Grubb, SE, PE
312.804.0813
grubb@aisc.org
GRAPHIC DESIGN MANAGER
Here are two facts, which are in direct be 200 technical sessions delivered by the Kristin Hall
conflict with one another. One, I’m one of best minds in the steel design and construc- 773.636.8543
those people that prefers to patronize local tion industry. There will be a trade show floor hall@aisc.org
restaurants and generally avoids chains. Two, with more than 250 exhibitors. There will AISC Officers
CHAIR
I love Popeyes, which, of course, is a rather be the exceedingly popular Thursday night Stephen H. Knitter
large restaurant chain (there are nearly 3,500 Conference Dinner. There will be keynote Geiger & Peters, Inc.
locations worldwide). addresses and the T.R. Higgins lecture. There VICE CHAIR
When I walk by this Popeyes location in will be opportunities to earn up to 21 PDHs. Hugh J. McCaffrey
Southern New Jersey Steel Co.
the morning, it’s closed. But in the evening, it There will be multiple conferences within a
SECRETARY/LEGAL COUNSEL
smells magical, and every day, I almost dare conference: the World Steel Bridge Sympo- Edward Seglias, Cohen Seglias
myself to wander in the front door and get in sium, QualityCon, and the NISD Conference Pallas Greenhall & Furman, PC
line. Of course, I make excuses not to: I should in Steel Detailing. There may or may not be PRESIDENT
save money, I should eat at home, there are fried chicken, but there will likely be green Charles J. Carter, SE, PE, PhD
better places to get fried chicken (and, let’s be chile (a popular local addition to Mexican SENIOR VICE PRESIDENT
Scott Melnick
honest, fried chicken isn’t exactly the healthi- food and anything else you might want to
VICE PRESIDENT
est food in the world anyway), and so on. slather it on; Google it). And one low regis- Carly Hurd
So the compromise is that we get chicken tration fee gains you access to all of this. VICE PRESIDENT
(and biscuits and other sides) from Popeyes And then there are the opportunities Lawrence F. Kruth, PE
twice a year: once on New Year’s Day (a tra- to catch up in person with colleagues and VICE PRESIDENT
dition that somehow started years ago) and friends, see a new place (or a place you’ve Brian Raff
once on some random day. been before and maybe visit some old VICE PRESIDENT
Mark W. Trimble, PE
My point is that you can always talk haunts), or simply get a change of scenery that
Editorial Advisory Panel
yourself into or out of anything. Take work is fortuitously tied to an event geared toward Caroline R. Bennett, PE, PhD
conferences, for example. They can seem making you better at what you do. And keep University of Kansas
expensive. They can take you or your in mind that this will be the first in-person Amanda Dean, PE
employees away from work for a few days. Steel Conference since 2019—all the more Walter P Moore
Bryan Frazier,
And they can seem unnecessary (though reason for those of us who are still working Zalk Josephs Fabricators, LLC
ask yourself how many other “unnecessary” from home all or at part of the time to go. Keith R. Griesing, PE
things you’ve talked yourself into doing or And did I mention that it’s in Denver? You Hardesty and Hanover
buying throughout your life and ended up may have heard that the Mile High City is Stephen H. Knitter
being glad you did). But the best ones are rather fun and is located near lots and lots of Geiger & Peters, Inc.
investments in your livelihood. mountains. Stick around after the conference Advertising Sales
Yes, this is the point where I remind you and make a vacation out of it! As a former M.J. Mrvica Associates, Inc.
2 W Taunton Avenue
that NASCC: The Steel Conference is just Colorado resident, I can assure you there’s Berlin, NJ 08009
around the corner. This year’s show is taking plenty to do in the area. 856.768.9360
mjmrvica@mrvica.com
place March 23-25 in Denver. Registration Happy new year, and we look forward to
Address Changes and
opens on January 10, and you can find out seeing you in Denver! Subscription Concerns
more—and register—at aisc.org/nascc. If 312.670.2401
subscriptions@aisc.org
you’re already planning to attend, great, we’ll
see you there! If you haven’t quite made up Reprints
Kristin Hall
your might yet or are in the process of talking Geoff Weisenberger 773.636.8543
yourself into it, allow me to help. There will Senior Editor hall@aisc.org
6 | JANUARY 2022
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Scooping up
the PDHs
AISC Continuing Education
Education Archives
Did you know that AISC offers 30-minute to 6-hour
presentations on demand? Viewing is free—so grab some
hot chocolate (extra marshmallows!) and check them out!
And if PDHs are what you’re after, you can purchase,
take, and pass a quiz to earn a certificate. There are
over 200 hours of options to choose from.
aisc.org/educationarchives
Smarter. Stronger. Steel.
American Institute of Steel Construction
312.670.2400 | www.aisc.org
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.
All mentioned AISC codes, standards, or
manuals, unless noted otherwise, refer to
the current version and are available at
aisc.org/specifications.
Strengthening Existing
Columns
I have a question about dealing with the
pre-load in an existing column that is to
be reinforced by adding plates. The AISC
2013 webinar “Design of Reinforcement
for Steel Members” (which you can
access at aisc.org/educationarchives;
note that PDHs are available) indicates,
on slides 42 and 43, that whether the
reinforcement is stabilizing or non-
stabilizing should be considered.
Is the concept of stabilizing and
non-stabilizing reinforcement valid,
and what is the source for the limit on
the reinforced radius of gyration?
Pre-load does reduce the strength of
columns. However, this detrimental effect
can be partially or wholly offset by other
beneficial effects. For some conditions,
safe designs can be obtained with the
equations in AISC Specification Section E3,
which define the AISC Column Curve
(curve expressing the relationship between
flexural buckling and slenderness ratio). In
this case, a safe design can be defined as
the condition where the beneficial effects
equal or exceed the detrimental effects.
I developed the design guidance in the
2013 webinar based on an evaluation of the
available research. (Although I am planning
to write an AISC Engineering Journal
article, it has taken longer than expected.)
Residual stresses are self-equilibrating
stresses built into the member in the
unstressed condition (no applied load).
Due to uneven cooling after the rolling
process, all steel shapes have residual
stresses. I-shaped members usually have
compression residual stresses at the
flange tips. Although the magnitude can
vary significantly, they are often assumed
Modern Steel Construction | 9
steel interchange
to be about 30% to 40% of the yield load. The beneficial effects are the residual axis. The differences are caused by shape
stress. Longitudinal fillet welds cause welding stresses and the locked-in tension factors, geometric imperfections, and
residual tension stresses in the connected stresses caused by the pre-load. material imperfections (including residual
members near the weld. These stresses are Pre-load does not affect buckling stresses). The AISC Column Curve is a
approximately equal to the yield stress of in the elastic range. However, the yield lower-bound curve based on a statistical
the base metal. point in compression is dependent on the analysis of many shapes. Many of the
The locked-in stresses caused by magnitude of the locked-in compression shapes included in the analysis had residual
the pre-load can be considered residual stresses. This is important because any compression stresses at the flange tips,
compression stresses acting on the original yielding causes a significant reduction which is the most detrimental location.
cross-section. Because the reinforcing plates in buckling strength compared to the For non-preloaded columns with welding
are unstressed (excluding residual stresses) elastic section. For a given (non-slender) residual stresses near the flange tips, the
until an additional load is added to the column geometry, the flexural stiffness AISC Column Curve is conservative.
reinforced column, the plates effectively about the buckling axis is the primary After reviewing the available research,
have locked-in tension stresses caused by variable affecting the buckling strength. I determined that when rr ≤ 0.85ro, the
the pre-load. Conceptually, this is clearer if When a portion of the column yields, that AISC Column curve is appropriate for
we think about the stresses in the reinforced yielded portion can be assumed to have designing field-welded and pre-loaded
member if the pre-load is removed after the a negligible contribution to the flexural columns. This applies only to doubly
reinforcing plates are welded. stiffness of the cross-section. Therefore, symmetric shapes with a controlling limit
If everything else is equal, including inelastic columns are more efficient when state of flexural buckling. In practice, I
the initial out-of-straightness of the the elastic areas are located farthest from had used this method on several projects,
column, the beneficial and detrimental the centroid of the reinforced section. even before it was presented in the 2013
effects can be evaluated based on the All steel shapes have different column webinar. Ultimately, you must use your
locked-in stresses. The detrimental effects curves that define the flexural buckling judgment to determine what is appropriate
are the residual compression stresses and strength. For many shapes, the buckling for your situation.
the locked-in stresses caused by the pre- curve is also dependent on the buckling Bo Dowswell, PE, PhD
Weak-axis Shear in a Wide Flange Member
I am using Equation G6-1 of the 2016 I believe the provision is presented elements,” and each of these elements
AISC Specification for Structural Steel the way it is because “doubly and singly may or may not have identical
Buildings (ANSI/AISC 360), but I am symmetric shapes” could include one, dimensions (tf, bf).
not sure I am using it correctly. Even two, three, or more “shear resisting Larry Muir, PE
though the wide-flange member is doubly
symmetric, the equation only seems
to allow me to account for the shear
strength of a single flange? Why can’t we
consider the strength of both flanges?
You have misunderstood the intent.
Equation (G6-1) provides “…the nominal
shear strength, Vn, for each shear resisting
element…” It is not intended that you use
“the strength of just one flange element”
as you have interpreted the requirement.
You can use both flange elements.
Bo Dowswell, principal with ARC The opinions expressed in Steel Interchange do not
necessarily represent an official position of the American
International, LLC, and Larry Muir Institute of Steel Construction and have not been reviewed.
are both consultants to AISC. It is recognized that the design of structures is within the
Steel Interchange is a forum to exchange useful and scope and expertise of a competent licensed structural
practical professional ideas and information on all phases engineer, architect or other licensed professional for the
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 | JANUARY 2022Better Together
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aisc.org/publications | 800.644.2400steel quiz
AISC turned 100 in 2021, and this month’s Steel Quiz takes a look at steel structures
from the past century. Learn more at aisc.org/legacy.
1 Proving to be stronger and more 2 What earthquake forever changed 3 What building took the title from the
weldable than its predecessor, A-7, the way steel structures are designed Empire State Building as the world’s
what year was A-36 introduced? and fabricated? tallest building?
a. 1962 c. 1960 a. Loma Prieta c. El Centro a. World Trade Center
b. 1966 d. 1964 b. Northridge d. Napa b. John Hancock Center (aka 875
North Michigan Avenue)
c. Sears Tower (now Willis Tower)
d. Salesforce Tower
4 What iconic steel structure was built
for a World’s Fair?
a. John Hancock Center
b. Space Needle
c. Citigroup Building
d. Sears Tower
5 Which U.S. President has their name
on a bridge in Louisville? (Hint:
Check the 1960s.)
a. Richard Nixon
b. Franklin Roosevelt
c. John F. Kennedy
d. Lyndon B. Johnson
6 What bridge has the 17th longest
main span in the world and longest in
the Americas?
a. Verrazano-Narrows Bridge
b. Rio Grande Gorge Bridge
c. Mackinac Bridge
d. Throgs Neck Bridge
7 What steel structure completed in
1969 contains striking X-shaped
exterior bracing?
a. Sears Tower
b. World Trade Center
c. One Liberty Place
d. John Hancock Center
8 What issue endangered the
Citigroup Center in New York? (Hint:
Check the 1970s.)
a. Underestimated seismic loads
b. Miscalculated wind loads
c. Potential liquefaction
d. Faulty fabrication
9 What steel was adopted in 1999 as the
new go-to material for rolled shapes?
a. ASTM A572 Grade 50
b. ASTM A500 Grade B
c. ASTM A992
d. ASTM A588
TURN TO PAGE 14 FOR THE ANSWERS
12 | JANUARY 2022steel quiz ANSWERS
1 c. A-36 was introduced in 1960 at the 6 a. New York’s Verrazzano-Narrows
National Engineering Conference. Bridge’s upper level opened in 1964,
the lower level in 1969.
2 b. The 1994 Northridge, Calif., earth-
quake spurred extensive research 7 d. The John Hancock Center (now
and work, leading to the develop- 875 North Michigan Avenue) is the
ment of the AISC Seismic Provisions fourth-tallest building in Chicago.
for Structural Steel Buildings (ANSI/
AISC 341, aisc.org/specifications).
8 b. Wind loads were deemed an issue
and corrected after a student raised a
3 a. The World Trade Center in Man- question to the building’s chief engi-
hattan used a novel system that neer. (See the People to Know item
relied on exterior walls to support the “Delayed Reaction” in the October
structure. 2012 issue, available in the Archives
section at www.modernsteel.com.)
4 b. Seattle’s Space Needle followed
the theme of “The Age of Space” 9 c. ASTM A992 has been the pre-
and was initially designed to with- ferred material specification for hot-
stand large earthquakes. rolled shapes since its adoption.
5 c. While still unnamed when Presi-
dent Kennedy was assassinated,
the bridge was later named the Everyone is welcome to submit questions
John F. Kennedy Memorial Bridge and answers for the Steel Quiz. If you
are interested in submitting one question
in his honor.
or an entire quiz, contact AISC’s Steel
Chicago’s John Hancock Center is known
Solutions Center at 866.ASK.AISC or
for its steel exterior X-bracing.
solutions@aisc.org.
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steelwise
A New Shine on Steel Design
BY NANCY BADDOO, CENG, AND MARK HOLLAND, PE
A look at the new AISC Specification for Structural Stainless Steel.
Premier Industrial/Westinghouse
A stainless steel support structure was used
for the passive cooling system in the containment
structure at the Vogtle Nuclear Power Plant (Units 3 and 4)
in Burke County, Ga. The tower is 30 ft tall and 11 ft square,
and made from duplex stainless steel S32101 plate and HSS.
AS THE DEMAND for resilient, long- for the Design of Cold-Formed Stainless Steel following is a brief look into the new publi-
lasting structures with low maintenance Structural Members—has been around for cation and how it harmonizes with the 2016
requirements grows, so does the demand decades, there wasn’t a dedicated publica- AISC Specification for Structural Steel Buildings
for stainless steel in construction—and tion for welded and hot-rolled stainless (ANSI/AISC 360-16); both publications can
AISC has recently released a specification steel products until AISC published the be found at aisc.org/specifications.
dedicated to structural stainless steel. first edition of Design Guide 27: Structural
Stainless steels are attractive and highly Stainless Steel in 2013 (aisc.org/dg). Stainless Applications
corrosion-resistant steel alloys with favor- Subsequent interest from the industry First, it’s important to consider where
able strength, toughness, and fatigue char- spurred AISC to develop a specification structural stainless steel can be most useful
acteristics. They can be fabricated using a dedicated to structural stainless steel. Work or make the most sense. Prominent stainless
wide range of commonly available engi- began with the establishment of the AISC steel applications include external structural
neering techniques and, like traditional Committee on Structural Stainless Steel, members that are in close proximity to salt-
structural steel, are fully recyclable at the which includes stainless steel fabricators and water, exposed to deicing salts, or in heavily
end of their useful life. welding experts, metallurgists, designers, and polluted locations. Stainless steels are com-
While guidance for designing cold- academics. And the new publication, Speci- monly used for platforms, barriers, and equip-
formed structural stainless steel members— fication for Structural Stainless Steel Buildings ment supports for the water treatment, flood
in the form of ASCE/SEI 8-02: Specification (ANSI/AISC 370-21), is now available. The control, pulp and paper, nuclear, biomass,
16 | JANUARY 2022steelwise
Chattanooga Boiler and Tank Company
Stainless steel is increasingly being used for transit-related structures.
Over the last 12 years, curved stainless steel and glass canopies have
been installed over the entrances to 40 Washington, D.C., Metro
stations. The canopies adopt a modular design and are made up of
austenitic stainless steel S31603 rectangular HSS.
chemical, pharmaceutical, and food and bev- and the first stage of the design process supplemental seismic provisions available
erage industries. In such applications, elimi- should involve characterizing the service for stainless steel. The new publication’s
nating the need for coating maintenance or environment. The publication’s Commen- provisions apply to austenitic and duplex
component replacement due to corrosion can tary provides guidance in this area, and stainless steels, and some provisions are
result in significant long-term maintenance AISC Design Guide 27 also advises on the also given on the use of precipitation hard-
cost savings. Stainless steel structural compo- durability of different stainless steel alloys ening stainless steels for tension members,
nents are also a popular choice for cladding in various environments. fittings, and fasteners.
supports, roofs, canopy supports, security bar- Chapters A through N of the Stainless
riers, and other applications that take advan- Synching Up Specification mirror the equivalent chapters in
tage of the material’s corrosion resistance, The scope of the Stainless Specification the AISC Specification. The one exception is
strength, and fire resistance to reduce mainte- generally matches the scope of the AISC Chapter I, which currently serves as a place-
nance requirements and improve safety. Specification. Although structural stainless holder to retain the same chapter letters as
Choosing the correct stainless steel steel has some promising properties for the AISC Specification while design rules are
alloy for a specific application is crucial, seismic applications, there are currently no developed for inclusion in a later edition.
Stainless Structurals
Stainless steel S31603 laser-welded sharp-cornered HSS, wide-flange beams, and angles were used as structural members for the glazed
entrance structures and elevator shafts as part of the renovation of the Southeastern Pennsylvania Transportation Authority (SEPTA) station at
30th Street in Philadelphia.
Modern Steel Construction | 17steelwise
Silverstein Properties
The high-strength duplex stainless steel S32205 mullions in the glazed façade of the 60-ft-tall three-sided atrium to 3 World Trade Center are sharp-
cornered profiles of built-up structural tube, which was selected for its resilient design characteristics and excellent corrosion resistance.
Although the necessary steps to deter- assessment requirements for specifying • Chapter H gives the same interaction
mine the structural capacity of stainless steel corrosion resistance. expressions as those in the AISC
members and connections are very similar • In Chapter B, the limiting width-to- Specification.
to those of carbon steel, the nonlinear stress- thickness ratios are generally lower than • The Chapter J rules for determining the
strain characteristics of stainless steel impact the equivalent values in the AISC Speci- available strength of connections are
certain aspects of structural behavior—e.g., fication and are organized into fewer cat- generally the same as those in the AISC
local and global buckling response. A com- egories. A method is provided for deter- Specification, apart from the provisions
parison of the Stainless Specification and the mining the strength increase in stainless for bearing strength and slip-critical
AISC Specification is summarized here: steel cold-formed hollow structural sec- connections.
• In addition to applicable material tions (HSS) due to strain hardening. • The Chapter K provisions are the
specifications, Chapter A of the Stain- • There are some differences in the rules same in both specifications, except the
less Specification provides product order for stability in Chapter C. scope of this chapter in the Stainless
requirements, as well as minimum • In Chapter D, the provisions are gen- Specification is limited to square or
erally the same as the AISC Specification, round HSS and box sections of uniform
although there is specific guidance for wall thickness.
stainless steel members where deforma- • In Chapter L, the nonlinear character-
tion needs to be limited. istics of stainless steels mean it is nec-
• The Chapter E expressions for determin- essary to use the secant modulus, as
ANSI/AISC 370-21
An American National Standard ing the flexural buckling strength differ opposed to the modulus of elasticity, for
Specification for from those in the AISC Specification. estimating deflections.
Structural Stainless • The Chapter F expressions for deter- • Chapter M contains some different
Steel Buildings mining the lateral-torsional buckling provisions that are necessary due to
strength differ from those in the AISC the different chemical compositions of
June 11, 2021
Approved by the Committee on
Structural Stainless Steel
Specification. stainless steels compared to carbon steel.
• In Chapter G, the provisions for shear Storage and handling measures to avoid
are generally the same as those in surface-finish damage are also given.
the AISC Specification, apart from the • In Chapter N, the requirements for
expression for calculating the web shear inspection and testing of welding in
strength coefficients. Provisions for tor- accordance with AWS D1.6/D1.6M
sion are given in Chapter G, as opposed replace those for carbon steel, where
to Chapter H. AWS D1.1/D1.1M is referenced in the
AISC Specification.
18 | JANUARY 2022steelwise
• There are some differences in the rules Inside Stainless Steel
for design by advanced analysis given in Stainless steels are a family of corrosion- and heat-resistant steels containing a mini-
Appendix 1. mum of 10.5% chromium and a maximum of 1.2% carbon. There is a wide range of
• Appendix 2 gives a deformation-based stainless steels with varying levels of corrosion resistance, strength, and weldability.
design method for determining the This array of properties is the result of controlled alloying element additions, each
strength of stainless steel cross sections, affecting specific mechanical properties and the ability to resist different corrosive
considering the benefits of strain hard- environments.
ening. It offers an alternative and less With a combination of a minimum chromium content of 10.5%, a clean surface,
conservative way of determining mem- and exposure to air, a transparent and tightly adherent layer of chromium-rich oxide
ber available strengths to the traditional forms spontaneously on the surface of stainless steel. If scratching or cutting dam-
methods given in Chapters D, E, F, and ages the film, it reforms immediately in the presence of oxygen. As long as the
H of the Stainless Specification. stainless steel alloy is corrosion-resistant enough for the service environment, it will
• The provisions regarding fatigue in not react further with the atmosphere. No applied coatings are necessary through-
Appendix 3 are the same as those in out the lifetime of a component.
the AISC Specification, although certain Stainless steel components are available in a range of finishes, from a standard
detail classes are removed as they fall mill finish suitable for applications where cosmetic appearance is less important to
outside the scope. brushed, polished, and even colored finishes for architectural applications.
• For fire design in Appendix 4, the
strength and stiffness degradation fac-
tors and the expressions for determining
the nominal compressive and flexural
strength for design by simple methods
of analysis are different from those in
the AISC Specification.
• In Appendix 5, the same procedures
apply to evaluating existing structures
as those in the AISC Specification.
• The provisions in Appendix 6 for the
required strength of bracing members
are different than those in the AISC
Specification.
• Appendix 7 gives the expressions for
modeling material behavior for stainless
steel at room temperature and elevated
temperatures.
Note that the Stainless Specification is a Stainless Structurals
standalone document with its own code of
standard practice, Code of Standard Practice for
Structural Stainless Steel (AISC 313-21); next
month’s SteelWise will provide information
on this forthcoming publication. In addition,
the second edition of Design Guide 27 will
be published at the same time as the Stain- Nancy Baddoo (n.baddoo@steel-sci.com)
less Specification to serve as its “handbook,” is an associate director with the Steel
providing examples and section property Construction Institute in the United Kingdom.
and member capacity tables for a range of She and her SCI colleague Francisco Meza
structural sections. (At present, there is no prepared the first draft of the AISC Specification
U.S. specification giving a standard library of for Structural Stainless Steel Buildings and are
sizes of stainless steel sections for structural also joint authors of the second edition of AISC
applications, so the tables cover the range of Design Guide 27: Structural Stainless Steel,
practical section sizes in typical use.) which is expected to be published later this year.
With the new stainless steel standard, its Mark Holland (mholland@pvsteel.com) is
related code, and the updated stainless design chief engineer at Paxton and Vierling Steel Co.
guide at their fingertips, designers will be able and chairs the AISC 370 Committee for
to design economic stainless steel structures Structural Stainless Steel.
with long service lives and low maintenance
requirements and, generally, get the most out
of their stainless steel projects. ■
Modern Steel Construction | 19field notes
By the Book
INTERVIEW BY GEOFF WEISENBERGER
As one of AISC’s longest-tenured employees, Cindi Duncan has wrangled countless
committee members to keep publications on track and on schedule.
CINDI DUNCAN HAS SEEN a lot of various committees to keep AISC’s publi- up changing my direction to architectural
changes to the steel construction industry cations on schedule, her advice to the next engineering in the middle of my junior year.
over the years—not to mention a lot of generation of female engineers, and more.
standards. What made you change your major/focus?
AISC’s longtime director of engineering Where are you from, and where did you I’d taken a lot of liberal arts classes and
has spent much of her nearly three decades grow up? really enjoyed that, but then one day I real-
here guiding the development of our many I grew up in Osceola, Iowa. I had a fairly ized how expensive it was to go to medical
standards and manuals (and sometimes modest upbringing in a blue-collar family, school. My parents worked really hard for
Design Guides and Engineering Journal), but my dad worked hard to move up to a me to go to college. They always supported
encouraging the process’ evolution as well sales position for a linen company and then me even though they didn’t have that same
as being part of the evolution of the engi- eventually changed careers and owned his experience, and I knew they couldn’t help
neering profession itself. own business. My mom helped him and support me through a medical school edu-
As she nears retirement later this year, also sold real estate. Neither of my parents cation. I really enjoyed the sciences, and my
she reflects on how she got into the con- has a college degree. I’m the third of four roommate’s dad owned a structural engi-
struction world (after taking a detour from children and ended up being the first in the neering company in Denver, and I thought,
an early pre-med path), how she’s been family to get a college degree. “Oh, that sounds really interesting, designing
able to bring disparate parties together on buildings and constructing them.” And I
That’s great! On that note, where did changed to architectural engineering at that
you go to school (college)? point and ended up getting a bachelor of sci-
Field Notes is Modern Starting in middle school, when I took ence in that field from CU. And then I went
Steel Construction’s my first biology class, I wanted to be a doc- on to get a master of engineering degree
podcast series, where tor. So I started out at the University of (civil-structures) from Cornell University.
we interview people Iowa in pre-med/liberal arts classes. After
from all corners of two years, I transferred to the University That’s quite the change in direction!
the structural steel of Colorado-Boulder, mainly because my How did you get started at AISC?
industry with interesting stories to tell. family moved to Colorado, and it was a After getting my bachelor’s degree,
Listen in at modernsteel.com/podcasts. good excuse to get out of Iowa. I ended I worked in Toledo, Ohio, as a project
20 | JANUARY 2022field notes
engineer at the Lathrop Company. I was fabricators, producers, educators, and con- than men at AISC. It is good that AISC is
working in a field trailer and joined the sulting engineers, so you can imagine the now hiring women engineers regularly
project when they were drilling caissons, disagreements that may come up. When I now—but I think the percentage of women
and I remember wearing tall rubber boots first came to AISC in the mid-1980s, the big going into civil engineering in general
and getting stuck in the mud trying to walk debate I recall was related to which column compared to men has stayed about the same
around to review the project. I was not curve to adopt in the new LRFD Specification. since the mid-1980s for various reasons.
excited about being in the field, nor the This debate was primarily between educa-
lack of respect I experienced due to being tors, and you may be surprised how passion- What advice do you have for young
a female, so I went back to school after a ate they were about their related research. It women looking to get into engineering
year and a half, and that’s when I got my is interesting what can cause a heated debate, or construction in general?
master’s degree in civil engineering/struc- from italicizing glossary terms in the specifi- I suggest getting as much education in
tures. And then I ended up in Chicago as cation to whether to remove ASD and have your field as you can, including a master’s
my husband at the time took a job there. only the LRFD method of design. This has degree, then getting licensed as soon as you
I actually answered a Chicago Tribune ad been the most recent debate. are eligible. I made the mistake of letting
for a staff engineer position at AISC and I think in general, the technical debates life get in the way and put off my registra-
interviewed with Dr. Geerhard Haaijer, have been less volatile in the past 15 years tion, which made it very difficult to pass the
who was the vice president of engineering or so because most of the AISC standards licensure exams, especially since I have spent
and research at the time. I always say I got are now ANSI-approved, meaning that the minimal time in my career doing design.
the job because he knew my steel professor, consensus bodies approving the standards
William McGuire, at Cornell. have to be balanced with equal parts industry, You’re planning to retire later this year.
general interest, academia, and consulting What are you looking most forward to
How long have you been at AISC? engineers, and they have to follow a very when it comes to retirement?
I started at AISC in 1985, left in 1992 defined process, requiring 75% approval of a My time will be my own, all of the time!
to stay at home and raise my kids, and then revision, and all negatives have to be fully vet- I can sit down and play the piano when-
returned in 1997 and basically picked up ted and responded to. If a negative is found ever I like and spend all day learning a new
where I left off. Somewhere along the line, non-persuasive and the voter doesn’t wish piece if I wish. I can help my aging parents
I was promoted to senior engineer and then to remove the objection, the negative com- out or spend the day with my grandson. I
director of engineering. I have had various ment/responses have to be circulated and the would also like to make more quilts. I made
roles through the years, including secretary pertinent revision recirculated, allowing the my first quilt for my grandson when he was
of different task committees, from nuclear full committee to vote again. born. And I’d like to help my mother write
design to seismic design, and I currently her memoirs and publish them. I have an
serve as secretary of the Committee on I’m glad the volatility has lessened. Back interest in writing a book, too, just not sure
Specifications, Committee on Manuals, and to your history at AISC, I understand what topic yet! ■
Committee on Structural Stainless Steel. I that you were the first female engineer
have also been editor of Engineering Journal hired here. Can you talk a bit about that This column was excerpted from my conver-
and directly responsible for the develop- experience? sation with Cindi. To hear more about her,
ment of AISC’s Design Guides in the past. For the first seven years of my tenure at including her musical skills, her thoughts on
AISC, I am fairly sure I was the only female green and red chile, and her favorite things
Can you tell me one of your biggest suc- at the committee meetings. It is something about Chicago and Santa Fe (she splits time
cess stories in terms of working on an I got used to and was already used to since between the two and will be spending a lot
AISC publication? most of my classmates were men. I have to more time in one of them after she retires),
Most of my work has been involved in admit there were occasional sexist or chau- check out the January Field Notes podcast at
developing and preparing AISC standards vinistic remarks from my male colleagues modernsteel.com/podcasts.
and manuals for publication. There isn’t at AISC, as well as the committee members.
any one story that stands out, but the fact I doubt that most of them were meant to be
that they come out on time (they’re sched- malicious, but I have never forgotten most
uled six years in advance) is a big success of the comments. They stick with you.
story every time it happens—especially
since the AISC Specification and Seismic I can imagine. Have things changed
Provisions, in particular, have to be available much in terms of women joining and
by a specific time in order to be adopted in being more accepted in engineering
ASCE 7 and the International Building Code. and construction in general?
After I returned to AISC in 1997, there
Have you witnessed some interesting or seemed to be a change in direction and pos-
heated discussions when it comes to a sibly a change in upper management so that
committee or a particular publication? finally, more women engineers were hired. Geoff Weisenberger
This happens often. Our commit- At one point in the last ten years or so, I (weisenberger@aisc.org) is senior
tees have a mix of industry folks, such as believe we have had more women engineers editor of Modern Steel Construction.
Modern Steel Construction | 21business issues Looking Ahead A group of construction professionals ponders the future of the industry and what can be done to ensure it’s a bright one. IT’S NEVER TOO EARLY to think about “The goal is to empower young lead- specifically on challenges that can create the future—and an unjaded perspective ers that are not yet fatally infected with resistance to change throughout the pro- can help expand the range of possibilities. the ‘I-do-not-trust-you’ bug to describe cess. These include issues such as mistrust That’s the mindset of a new panel a desirable future state for the construc- between team members, lack of transpar- of young design and construction pro- tion industry,” summarized Marc Dutil, ency between owners and stakeholders, fessionals. Initiated by AISC member president and CEO of Canam Group, and short-term thinking. The group fabricator Canam Group, the Future who helped launch the program. wholeheartedly believes these are solvable Leaders Program (FLP) gathers young Over the last two years, the group’s challenges and that now is the time for leaders (under the age of 40) from various participants have worked to identify the open dialogue, interdisciplinary trust, and branches of the architecture, engineer- most challenging and frustrating issues collaboration, and the goal is to shift the ing, and construction (AEC) industry for in the construction process—many of collective mindset of the AEC industry to open discussions about the state of the which can be traced back to the early improve relationships and create better industry and where it is headed. stages of projects—and have narrowed in outcomes for clients and project teams. 22 | JANUARY 2022
business issues
A recent panel discussion facilitated by Should owners ask for more collaboration According to Erdy, ‘’It’s really about
the FLP leaders featured four highly suc- between designers and contractors (gen- trust and how much you trust the team;
cessful professionals representing various erals and subs) during design? that’s the fundamental road to success.’’
construction disciplines, with many years The panel was unanimous that owners Tessier also added that there is a prob-
of industry experience and varied project should ask for more collaboration. lem in the construction industry: a lack
types between them: Frodyma said, “Yes, it’s important and if of collaboration and communication. To
• Scott Erdy, Lead Design Principal, you are not doing it, you should because improve collaboration, he stressed, the
Erdy McHenry Architects you’ll save time, you’ll weed out mistakes project team needs to create open lines of
• Janis Vacca, Principal, The Harman in design and make your building more communication and make sure that every-
Group efficient, cost-effective, etc.’’ one can bring their best ideas forward.
• Daniel Tessier, Vice President, Collaboration early on is important, ide-
AECOM Tishman ally with consultants, contractors, and client Do you think the emergence of new tools
• Robert Frodyma, Vice President of involvement, because trusting the team is the and technology—e.g., BIM, 4D schedul-
Design and Construction, Canadian key, noted Vacca. “You can build that trust ing (combining a traditional construction
Tire Real Estate Limited working together with the same purpose: schedule with a 3D model), and modular
Together, they answered some key ques- doing what’s best for the project and under- construction—is enough to help the indus-
tions about where the industry is headed standing the actual project priorities. When try keep up with the fast pace of today’s
and how to drive positive change. The everyone works together from the start, com- construction? What does the construction
following feedback was summarized by municates and listens to each other, you can industry need to change to ensure quality
members of the FLP team. understand their diverse perspectives.” and efficiency are maintained?
Modern Steel Construction | 23business issues
Scott Erdy Again, there was unanimous agree- trained and educated on soft skills in
ment amongst the panel that technology schools, with communication and people
will increase speed and agility to deliver skills being a top priority. We should be
construction projects more efficiently. pushing to integrate more of this train-
Vacca pointed out, “Let’s be honest, the ing into our education programs. There
number one stressor for everyone is is also the issue of fear: fear of not know-
money. Technology can impact the speed ing and fear of asking questions. We need
of delivery which ultimately correlates to to cultivate a climate where people feel
financial savings.” comfortable and safe in asking questions,
Erdy suggested that the best option in asking for help, and in looking to the
is where there is a collaborative relation- younger generation to help answer tech-
ship where models are shared in real time. nological questions.
However, the industry is very diverse in
the technology used by different-sized What would be the best advice to an
companies as well as different trades. “Our owner before selecting the project team
schools need to do a better job in teaching and the type of contract/bidding for
the new generation the technology and construction?
tools that will provide a common language Tessier’s advice was to be sure to select
in the industry,” he noted. engineers, architects, and contractors who
Janis Vacca Tessier added, “From a field office per- are good team players. “They should be
spective, our most critical tool has always able to collaborate respectfully and pro-
been the paper version of the drawings, and actively with each other,” he explained. “If
in the last five years this critical tool has possible, they would have collaborated pre-
turned into the iPad. Technology, used the viously together. There should be an open
right way, can fast-track a building. The line of communication between these three
one thing we need to make sure is that all and also with the client.”
parties involved are on the same page as to Vacca believes it’s also best to bring key
how to use the programs, and that includes subcontractors on board earlier with the
having access to adequate training.” design team. Erdy recommends know-
The consensus amongst the panel was ing the reputation of the people you will
that capacity for change and elasticity of work with. Finally, Marc recommends that
the mind is an individual phenomenon. clients should pay their professionals well.
As such, change starts with oneself, and “Contractors are not ‘out to get’ clients,” he
we should learn these competencies noted. “It’s not just about the money; their
as early as possible. They’re applicable pride is in a job well done.” Overall, the
both in the professional realm and in lowest-bidder approach was not recom-
personal lives. Students should also be mended as the end all, be all option.
24 | JANUARY 2022business issues
How do you see your role in construction have a major impact on the industry. He Daniel Tessier
projects evolving over the next few years? pointed out that we already use AI tech
The panelists predicted that technology saying, “At the most basic level, think of
will continue to improve, changing the all the auto-correct your phone does, or
design process and allowing all stakeholders jump into a fighter plane and start flying a
to understand projects more clearly. Erdy jet that’s auto-correcting to what it thinks
pointed out that we can use current technol- you want. That’s Revit in a nutshell.”
ogy to help everyone (from the client to the While the potential impact of AI may be
construction team) visualize the final prod- huge, both Erdy and Tessier think it’s best
uct, and find potential conflicts before proj- to resist the urge to dive head-first into new
ects are physically constructed. However, technologies. Erdy cautioned, “I think that
technology has also allowed stakeholders while our tools try to help us more, we must
to dehumanize aspects of construction, and remain masters of our tools.” Tessier added,
the decades-long trend of society deempha- “Technology has to be used correctly. I think
sizing the importance of tradespeople has that’s the key point. If we’re not using it
affected the quality of the trades today. correctly, whatever the program is, it’s a
Tessier noted that construction was waste of time or somebody could get hurt,
one of very few industries that didn’t stop whether hurt physically or financially.”
throughout the COVID pandemic because The FLP is an ever-evolving orga-
it is a critical service. Alongside technologi- nization of like-minded AEC industry Robert Frodyma
cal advancements, he would like to see a professionals that are eager to engage in
change in the secondary school education an impactful dialog and create a road-
system so that the trades are encouraged map and strategy for disseminating ideas
as a valued career, which contradicts his and future-oriented practices. Over the
experience where kids were pushed into coming year, the group will continue its
the trades when they were not considered thought leadership approach, includ-
“good enough” to do anything else. ing industry talks, internal dialog, and
public dissemination of forward-thinking
What innovations in technology do you ideas. Please join us in shaping the next
believe will impact your day-to-day generation of talent and moving the
work the most? What will this change industry towards more open models of
offer the other project stakeholders? communication and collaboration. If our
The panelists highlighted cutting-edge mission resonates with you, reach out via
technological advances, support for the the LinkedIn page for “Future Leaders
skilled trades, and a cautious approach to AEC’’ (linkedin.com/groups/12478835)
adopting new technology. From Erdy’s to stay informed and discover ways to get
perspective, artificial intelligence (AI) will involved. ■
Modern Steel Construction | 25Early
to
Rise
BY JIM FOREMAN AND WADE LEWIS
WORKING CLOSELY WITH A STEEL FABRICATOR is the Early Engagement
best way to ensure your steel details are efficient and economical. The new tower, including mechanical penthouses, is 205 ft tall,
And the more complex a project, the greater the benefit. and the structural system comprises steel columns, composite steel
Tower 3, a 13-story addition to an existing inpatient pavil- floor framing, and drilled pier foundations, with a concrete lateral
ion at UCHealth University of Colorado Hospital on the system. A key feature of the building is its open ambulance bay
Anschutz Medical Campus in Aurora, Colo., is one such com- on the north side, where a large, open space was critical to allow
plex project. Built to meet a growing demand for medical care, ambulance drivers direct access in and out of the drop-off zone. To
this new addition presented a variety of design challenges and accommodate this feature, two-story steel trusses were designed
goals. One of them—for the entire project team—was produc- to keep a 160-ft by 130-ft area of the building free of interior col-
ing a structural design that facilitated an aggressive construc- umns at the lowest level and also support the 11 steel-framed floors
tion schedule. To accomplish this, the general contractor and above the ambulance bay.
steel trade partners were included early in the design process. Haselden Construction, the general contractor, was engaged
Steel systems and details were designed specifically for the at the start of the project to assist the design team, allowing for
fabricator and erector’s preferences and resulted in an efficient various structural systems and details to be studied, priced, and
design that could be built on schedule. Steel for the project scheduled to determine the best approach for constructability and
topped out in October 2021, and the new addition is expected schedule. Steel fabricator Puma Steel, also brought on board early,
to open this year. was involved in the steel design and detailing process and helped
26 | JANUARY 2022For a new Denver hospital,
early coordination allowed for mill
order and steel detailing packages
to be issued prior to construction
documents. The result?
A faster project.
Steel for Tower 3 of the UCHealth University of Colorado Hospital on
the Anschutz Medical Campus in Aurora, Colo., topped out this past
October, and the addition is expected to open this year. Bringing
fabricator and detailer Puma Steel on board early in the project
helped optimize connection design and keep things on schedule.
EYP
with connection type selection. For the most
typical and complicated connections, the two
companies assisted the design team with select-
ing connections that balanced material cost and
labor with schedule.
To assist with the schedule, the design team
issued several steel mill order and detailing pack-
ages before final structural design was complete.
Mill order package and mill rolling schedules
were coordinated for optimal efficiency, and the
detailing package deadlines were coordinated
with fabrication and erection schedules.
High-Strength Steel
Grade 65 (A913) steel sections were chosen
for the tower project. When comparing prelimi-
EYP
nary designs between 50-ksi members and 65-ksi
Modern Steel Construction | 27You can also read
