Shankar Nair has engineered bridges and buildings that

Transcription

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Shankar Nair has become a noted bridge engineer, but he also had a hand on some of the skyscrapers dotting the Chicago skyline.
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12 Shankar Nair:
All about the basics
16 Constructability
drives bridge design
38 Structural changes in the
2012 International Building Code
Relying on the brass tacks of physics and
mathematics, Shankar Nair has engineered
bridges and buildings that prove all you need
sometimes are the fundamentals to create
magnificent structures.
Need for speed drives the emergency replacement
of the Lake Champlain Bridge to restore a region’s
mobility.
Part I of this two-part article provides a brief overview
of the more significant changes to Chapter 16 of the
IBC, which covers design loads for structures.
BY THEODORE P. ZOLI, P.E., M.ASCE
BY JOHN R. HENRY, P.E.
30 2013 Best Firms To Work For
42 ‘Prognosis Negative’
The 2013 Best Firms To Work For award recognizes
A/E/P and environmental consulting firms for their
superior achievements in workplace practices,
employee benefits, employee retention rates and
much more.
Like in the fictional movie, it is clear that careful
attention to details and proper diagnosis of the
issues at hand will minimize risk, as well as longterm consequences
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• Wood rising higher
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on the cover
Shankar Nair, a strong foundation for sound engineering.
Cover photo: Michael Schacht, www.312elements.com
July 2013
Structural Engineer
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Structural Engineer
July 2013
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Best Firms To Work For
One of the features in this month’s issue of 6WUXFWXUDO(QJLQHHU is all about our annual Best Firms To
Work For awards.
Being a great place to work is more critical today than ever. Even though the recession of 2007-2012 had
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truly outstanding employees do).
I like to put myself in the shoes of others every so often. This topic got me thinking about what I would
be looking for if searching for a job in our business today. Here are some of the things I would be looking
for in an employer:
1. Inspired leadership. Nothing good is going to happen without inspired leadership. This means the
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2. The organization has a real purpose and ongoing focus on a worthwhile mission and it’s clear how the
role relates to that. ,WLVFULWLFDOIRUPHDQGRWKHUVWREHGRLQJVRPHWKLQJWKDWLVZRUWKGRLQJ,W·VWKH
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will not do it. Good people want to know they are making a difference in others’ lives and not wasting
their lives on unimportant activities and trivia.
3. A place that has a culture of sharing glory and rewards. Any company that is too ego-driven by the
founder/owner is probably not one I would be happy working for. Sometimes this situation is not as
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We’ve got another great issue here of 6(IRU-XO\:HVLQFHUHO\KRSHWKDW\RXHQMR\DQGEHQHÀWIURPLW
Mark C. Zweig, [email protected]
6
Structural Engineer
July 2013
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A peculiar prognosis
This month’s article HQWLWOHG ´3URJQRVLV 1HJDWLYHµ LQ DGGLWLRQ WR
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demonstrating that accurate diagnosis of a structural problem requires
more than just obtaining test results. It also requires proper interpretation
of those results in order to determine the cause of the problem and draw
an accurate conclusion as to the condition of the structure.
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a nearby building and expressed interest in possibly leasing space in our
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they had been told that their existing building was unsafe and needed
to be evacuated in six months. They asked if the leasing agent could
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opinion and a nice lease deal.
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a testing laboratory to investigate the problem. An on-site testing
program revealed that carbonation of the concrete had occurred at the
lower level columns. Carbonation occurs when carbon dioxide from the
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level of the concrete and reducing the concrete’s ability to protect the
reinforcing steel from corrosion.
The testing laboratory issued a report stating that the carbonation would
continue and render the building unsafe in six months. The report even
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thought it was somewhat ironic that the closing paragraph of the report
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to determine that the original design of the concrete structure was
conservative. Upon further investigation of the lower level columns that
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more likely due to corrosion of the reinforcing steel resulting from leaks
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corrosion from carbonation. This conclusion was supported by the fact
that the depth of carbonation had not yet penetrated the full thickness of
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were inside the building and not exposed to the atmosphere.
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measures to reduce the ingress of moisture into the concrete.
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that they could decide whether to stay in the building or abandon it.
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approximately 20 lawyers were in attendance!
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with a graph showing typical column strength versus time. The graph was
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WKHWLPHD[LVLH]HURVWUHQJWKLQVL[PRQWKV+RZHYHUWKHUHZDVRQO\
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testing engineer how the slope of a line could be determined using only
one data point. His response was that the column strength at the time of
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there was no data at the time of original construction and that the testing
engineer’s conclusion was only one possibility and could be overly
conservative.
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Daniel A. Cuoco, P.E., F.ASCE, [email protected]
8
Structural Engineer
July 2013
AUGUST
Feature: Tech solutions for project management
Today’s increasingly complex building projects challenge A/E
firms to achieve client goals along with their own internal
resource utilization and profitability objectives. As a result,
it’s vital to get a complete picture of project performance and
management across the board. As with other areas of our
lives, software has become the answer.
Materials feature: Where structure meets style
As U.S. building markets continue to improve, so does
the outlook for multifamily housing. Mid-rise, mixed-use
developments are filling in urban skylines across the country
and an increasing number of engineers and architects are
using wood to take advantage of that opportunity. Owners of
The Stella, a new 244-unit apartment complex in Marina del
Rey, Calif., recently did just that.
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Wood rising higher
There is growing movement among leading architects to embrace
wood as a structural replacement for concrete and steel in mid-rise
and even high-rise projects. The trend and the growing exploration of
new engineered and hybrid technologies is driving the wood to soaring
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structures within their lifetime.
Correction
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Massachusetts Institute of Technology to get a master’s degree and engineer’s
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July 2013
Structural Engineer
9
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Code query
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interesting reading.
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2FWREHU
I took a look at Section 3 in the 2005 and 2010 versions of the Code of Standard
Practice. One of the major differences is that an option (3) for connection design was
added, which requires that the connections be designed by a licensed professional
engineer working for the fabricator. This is a requirement that has been included in
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one of the consequences of the collapse of the Kansas City Hyatt walkways in 1981.
I’ve got a webpage if you’re interested: abeldetailing.com. I’ve been a joist and
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In the case you mentioned, I suspect that the designer is looking to the Code
of Standard Practice solely to provide requirements for fabrication, erection,
and other contractor responsibilities, which constitute the major portion of
the Code’s content. By excluding Section 3, I would think that there should
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responsibility for connection design.
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decided to get your take on one of the little idiosyncrasies some engineers have
been practicing.
Hope this is helpful.
Dan Cuoco
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Lack of control
To the Editor:
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rules I am to abide by.
This has been going on for the last couple of years. What I’d like to know is
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Thank you,
Don Abel
Don,
Took a while for me to respond because I wanted to research this a bit to see how
the latest AISC Code of Standard Practice compares with my past experience.
Frankly, I’m somewhat surprised to see that the entire Section 3 was excluded, since
this would not only exclude the designer from “abiding by the rules,” but would
exclude you as well with regard to a very important responsibility – connection design.
On the other hand, Section 3 can possibly be interpreted, albeit unreasonably in my
opinion, to require the designer to provide a “perfect” set of contract documents.
For example, it states that “all geometry and working points necessary for layout”
shall be provided on the structural design drawings. In some cases, geometry and
dimensions are best referred to architectural drawings, rather than duplicating them
RQWKHVWUXFWXUDOGUDZLQJVLQRUGHUWRDYRLGFRQÁLFWLQJLQIRUPDWLRQGXHWRODVW
minute architectural changes. Perhaps the designers that exclude Section 3 have
been burned in the past by delay claims because their drawings did not include
every dimension. There are other similar examples. Maybe it was just easier to
H[FOXGHWKHHQWLUH6HFWLRQUDWKHUWKDQSURYLGHPXOWLSOHTXDOLÀFDWLRQV
10
Structural Engineer
July 2013
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of a primary requirement for such testing. There appears to be no plan to erect a
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Even though the investigators may attempt to use the building itself as its
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uncontrollable factor in such tests will be the weather.
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LIRQWKHGD\\RXWHVWWKLFNQHVV´$µLWLVDVXQQ\)GHJUHHVRXWVLGHZLWKD
PLOHDQKRXUZLQGDQG5+EXWRQWKHGD\\RXWHVWWKLFNQHVV´%µLWLVDQ
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,IWKHDQVZHULV´:HZLOOFRUUHFWIRUWKRVHYDULDQFHVE\FRPSXWDWLRQµLWZRXOG
appear that the investigators are fooling themselves and the whole point of
building a full scale model becomes moot.
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VRODUUDGLDWLRQDOOYDU\HQRUPRXVO\KRXUE\KRXUDQGFHUWDLQO\GD\E\GD\DQG
WKHLUHIIHFWRQKHDWORVVDQGKHDWJDLQIURPDEXLOGLQJLVHQRUPRXV6RZLWKRXW
DQ LQVWDQWDQHRXV LGHQWLFDO ´FRQWUROµ EXLOGLQJ IRU FRPSDULVRQ WKH YDOXH RI DQ\
PHDVXUHPHQWVWDNHQLVOLNHO\WREHYHU\ORZDQGWKHFRQFOXVLRQVGUDZQVXVSHFW
Very truly yours,
Carl Mezoff, architect, P.E.
Stamford, Conn.
July 2013
Structural Engineer
11
EQXGTUVQT[
Shankar Nair: All about the basics
Relying on the brass tacks of physics and mathematics, Shankar
Nair has engineered bridges and buildings that prove all you need
sometimes are the fundamentals to create magnificent structures.
By Maureen Foody
Chicago is littered ZLWK QRWDEOH EXLOGLQJV IURP WKHLU IUDPHZRUN WR
KHLJKWWRFXWWLQJHGJHGHVLJQ,W·VDFLW\WKDWKDVD*HPLQLSHUVRQDOLW\
the old brick intermingling with striking new steel and glass. Shankar
Nair has assisted in creating many parts of that striking downtown.
1DLU LQLWLDOO\ ZDQWHG WR JR LQWR WHDFKLQJ EXW ´LQ HYHU\RQH
and his uncle wanted a teaching post to avoid the draft to Vietnam.
This proved to be a blessing in disguise. I turned to the consulting
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the universal language of science and mathematics. Nair wasn’t even
16 when he decided to go directly into engineering after attending the
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remembers a number of projects at Benesch as being especially challenging
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American education
After moving to the U.S. to pursue his Master of Science in Civil
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Alfred Benesch & Co. in Chicago as a structural engineer.
12
Structural Engineer
July 2013
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the authority to make all the engineering decisions without clearance
from anyone above. But I was also junior enough to spend all my time
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did not study plans of other tied-arch bridges. I just developed the
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The challenge for that project: Nair was able to reduce cost and avoid
the secondary stress issues common in box-section tie girders by
using I-section tie girders.
The Jefferson Barracks Bridge, which carries Interstate 255 over the Mississippi River from Illinois into Missouri. The view from below (during construction) shows the most important
structural innovation – the I-section tie girder. And this was at the time the longest tied arch in the world.
From bridges to towers
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had a hand in constructing some of the skyscrapers that dot the Chicago
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portion resulted in a highly economical structure while the steel portion
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of projects before settling down again at KKBNA Inc. as a principal
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New projects; old basics
Some projects in the works include two long-span bridges over the
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same basic processes he used early in his career for these projects.
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by a computer. This is done by an associate now but it was always by
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A hallmark example of this work is the extension of the CTA blue
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subway station under an existing multi-level parking structure. The
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Nair developed a combination underpinning and transfer system to
support the garage while the construction sequence continued without
a hitch. The project won an award for engineering excellence from
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Nair describes some of the challenges he and all structural engineers have
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LQ FRQIURQWLQJ WKH GLIÀFXOWLHV IDFLQJ WKH LQGXVWU\ IURP IDLOLQJ DQG
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work still being done around the world by structural engineers.
July 2013
Structural Engineer
13
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statics and the balance of forces in any structure and any part of a structure.
Eventually this will become instinctive and you’ll be well on your way to
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Finding his way
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happenstance. It didn’t have to end up this way but I’m very glad it did.
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Shankar Nair in his garage tinkering with the 620 horses of his Ferrari 599GTB
Fiorano, which he likes to take for rides on country roads in Wisconsin.
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Nair also contributes to the industry by serving on the Council on Tall
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The Old Plank Road Trail Bridge: A simple and direct solution to the problem of a
sharply skewed crossing.
The patented Eighth Street Bascule Bridge in Sheboygan, Wis. may be noted for the absence of a counterweight and the simple structure, the latter evident from the structural analysis model.
14
Structural Engineer
July 2013
When he isn’t using fundamental principles to
create structures or advancing the understanding
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Katharine. They met as graduate students at
University of Illinois-Urbana-Champaign while
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and two granddaughters. He also enjoys reading
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of op-eds in the Chicago Tribune in the mid- to
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Drive under the shadow of the skyscrapers he
helped design.
Maureen Foody is a freelance writer and editor who lives and
works in Chicago. She can be reached at [email protected].
Shankar Nair with daughter Janaki Nair and granddaughter Saraswati Guzzardo.
July 2013
Structural Engineer
15
EQPVGORQTCT[DTKFIGFGUKIP
Constructability
drives bridge design
Need for speed drives the emergency
replacement of the Lake Champlain
Bridge to restore a region’s mobility.
By Theodore P. Zoli, P.E., M.ASCE
Project owners
New York State Department of Transportation and Vermont Agency
of Transportation
Contractor
Flatiron Construction Corporation
Design consultant
HNTB Corporation
Detailer
Tensor Engineering, New York and Vermont approaches
Arch detailer
Candraft Detailing Inc.
Steel fabricator
High Steel Structures Inc.
Erection engineer
Erdman Anthony
When the Lake Champlain Bridge connecting Vermont
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and replaced the original bridge. The $76 million
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Before Vermont and New York declared states of
emergency and the New York State Department of
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The HNTB design team created several designs but the modified network tied arch design, featuring a network tied
arch main span, supported by triangular rigid frame elements at each end of the arch, was selected.
16
Structural Engineer
July 2013
$IWHU GHWHUPLQLQJ WKDW VWUHQJWKHQLQJ DQG UHWURÀWWLQJ WKH VWUXFWXUH allowed the contractor to construct the center arch span and approach
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WKH\ ZRXOG GHPROLVK WKH KLVWRULF VWUXFWXUH LPSOHPHQW D The heavy lift offered other advantages:
temporary ferry service and build a replacement bridge.
• Construction crews had easier access building the center span on the
Designed for constructability
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a delivery strategy to complete design on a compressed schedule • 7KHPRGLÀHGGHVLJQ·VGHOWDIUDPHSURYLGHGPRUHFOHDUDQFHPDNLQJ
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advertisement and permitting performed concurrently. HNTB
network tied-arch design.
Corporation was the design consultant on the project and designed
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of traditional cast-in-place decking. This eliminated the need for
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extensive formwork and lengthy cure times associated with cast-in7KH QHZ /DNH &KDPSODLQ %ULGJH LV FRPSRVHG RI D WRWDO RI HLJKW
place decks.
spans with one network tied-arch signature span. Total bridge length
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remained open for the duration of construction.
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An accelerated design schedule is meaningless if it results in a bridge ,Q DGGLWLRQ WR GHVLJQ GHWDLOV DQG PHWKRGRORJLHV RWKHU PHDQV RI
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turnaround times for shop drawing reviews and answering contractor’s
construction strategy informed the design.
requests for information were to be adhered to by the design team and
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The center arch span was maneuvered into place, suspended by four strand jacks, one stationed at each corner of the unfinished
bridge. The strand jacks raised the massive structure into place, chipping away at the 75-foot journey in 18-inch increments.
July 2013
Structural Engineer
17
VKVNGJGTG
At least it was to the construction team on the Missouri River Bridge
project when their initial concrete design priced over budget at almost
$45 million. They then had to scramble for other options.
Turned out the solution was steel. After coming up with a new design,
they turned to Nucor. And we were able to help them build a
beautiful, easy to maintain and environmentally friendly bridge at less
than half the cost of concrete. Who would’ve thought.
www.nucoryamato.com
It’s Our Nature.®
Heavy lift is successful
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any other time and when its stability was most compromised.
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erection sequence. Knowing the tension in each cable would change as
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simulated the load cases to ensure that while it was being pushed by
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remained at safe levels.
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Erdman Anthony not only monitored the amount of force each of the four
strand jacks carried to keep them as balanced as possible but also displacement
to make sure the four corners of the arch span remained as level as possible.
Best practices learned from an accelerated timeline for delivery
With an emergency mandate to reestablish the link between the two rural
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say the best jobs are the ones they receive in the fall because they have
the winter to prepare for work in the spring. Due to the need for speed on
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making the accelerated timeline the biggest challenge of this project.
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• Having the HNTB design team on-site and accessible during
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problems could be avoided proactively or addressed immediately.
• This project used traditional cofferdams and watertight enclosures to
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used to allow the contractor to work in the dry. These enclosures were
more like bathtubs with holes in the bottoms that sit on top of shafts
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dewatering all the way down to the bottom of the deep lake.
20
Structural Engineer
July 2013
Keeping the arch stable during the float was the most critical part of the erection
sequence. Knowing the tension in each cable would change as the arch was transported
and then lifted, HNTB designed the structure so cable tension could vary, depending on
the load applied to the structure.
Master of Civil
Engineering – Online
Build Your
Environment.
Help Shape
Your Future.
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July 2013
Structural Engineer
21
The new Lake Champlain Bridge is composed of eight spans with one network tied arch signature span. Total bridge length is
set at 2,200 feet with seven approach spans measuring up to 250 feet and a 402-foot-long network tied arch signature span.
The bottoms of the enclosures were precast and became a
permanent part of the piers. Only the walls were ultimately
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sat on top of those collars. The whole procedure worked very
well.
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frames anchoring either end of the center arch shortened the
main span and made the center arch span construction and lift
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Bridge is a model for success
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NYSDOT developed a plan to demolish the original truss bridge in just
over two months and to design and construct a new signature crossing
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as well as the teamwork between the two states and numerous local
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time- and cost-savings to the public.
In addition to their aesthetics, the five-story-tall delta frames anchoring either end of the center
arch shortened the main span and made the center arch span construction and lift easier.
22
Structural Engineer
July 2013
Theodore P. Zoli, P.E., M.ASCE is chief bridge engineer in charge of technical aspects of
HNTB’s bridge practice. Contact him at (212) 915-9545 or [email protected].
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Change orders, sureties and
master agreements
By Michael J. Baker, Esq.
Q: I am involved in a federal public works construction project. I was in a
meeting with the management team and we were discussing numerous
change orders that were pending on this project and our attempts to
negotiate the open items with the contractor. As part of the discussions,
one of the participants asked whether the contractor was entitled to its
negotiation costs incurred in negotiating change orders. The contractor
had included costs for its own consultants and attorneys’ fees since
it had retained them to help assist in the negotiation. Can you provide
some insight as to whether these costs are recoverable?
A: When parties to a government construction contract encounter
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EHLQFHQWLYL]HGWRQHJRWLDWHUDWKHUWKDQOLWLJDWHRYHUVXFKLWHPV7KLVLV
the general rule in many cases and describes accurately those involving
federal projects. The important thing here to keep in mind is to make
a distinction between contract claim preparation costs versus contract
administration costs. Only genuine contract administration costs tend
to be recoverable.
The obvious question is then: What is a recoverable contract
DGPLQLVWUDWLRQFRVW"&RQWUDFWDGPLQLVWUDWLRQFRVWVDUHW\SLFDOO\GHÀQHG
by their purpose. Think of it like this: If a contractor incurred the cost
IRUWKHJHQXLQHSXUSRVHRIPDWHULDOO\IXUWKHULQJWKHQHJRWLDWLRQSURFHVV
such cost would normally be a contract administration cost even if
negotiation eventually failed and a claim was later submitted. What I
would look for is genuine negotiations wherein the consultant or the
attorney actually assisted in the process involving negotiation over the
price of the changed work and furthers the process along in a material
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it would be advisable to try to discern which party’s action is keeping
the price open. One such way to avoid this type of claim for the cost of
consultants and attorneys is to have the owner issue a unilateral change
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subsequent negotiations may be seen as claims motivated to recover
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light of the unilateral change order.
24
Structural Engineer
July 2013
Q: Our firm operates for several clients under a master services
agreement to provide design and engineering services. We find that this
is convenient. Our work usually is based upon a purchase order issued
by a party we have the master agreement with, subject to the terms
in the master agreement. We have several long-standing relationships
and some of these master service agreements are lengthy and old.
What are issues that we should be concerned about in these types of
arrangements?
A: The most common complication in this type of arrangement is that
over time the master service agreement is not closely followed or
circumstances have evolved such that the purchase orders issued to
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read in light of the master service agreement terms and conditions. One
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inasmuch as the purchase orders tend to leave out material terms such as
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DQGFRQGLWLRQVODLGRXWLQWKHPDVWHUVHUYLFHDJUHHPHQW,QDQGRILWVHOI
WKLVLVQRWDSUREOHPXQWLOWKHUHLVDGLVSXWH7KHQWRXQWDQJOHWKHGLVSXWH
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WKH PLQGVµ DV WR WKH ZRUN EDUJDLQHG IRU LQ WKH SXUFKDVH RUGHU WKDW LV
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There is a certain appeal to having this prearranged master service
agreement form. Such agreements help avoid negotiations over general
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WKHXOWLPDWHGDQJHULVWKDWRQDIXWXUHSXUFKDVHRUGHURUWDVNRUGHUWKH
parties forget what the master service agreement requires of them and
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territory when a sudden dispute arises that they did not anticipate. The
master service agreement works great when parties actually follow the
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master agreement. They do not work so well when parties’ conduct and
purchase orders make a departure from the written agreement.
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Q: There was no declared default on a project that I was working on
with respect to the contractor’s performance. However, the surety
funded the completion of the project. Is it a surety takeover of the
project under such circumstances? If so, is the surety then entitled
to the contract proceeds? The surety is now asking for the contract
proceeds after it paid to complete the work.
A: All that is necessary is for the contractor to default under its
contract. There does not need to be a declared default unless a bond’s
terms create preconditions to that trigger of default. The question also
focuses on whether the surety would be entitled to contract proceeds
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DVVHUWDOHJDOGRFWULQHFDOOHG´HTXLWDEOHVXEURJDWLRQµKHUHWRFROOHFW
the contract proceeds. Equitable subrogation basically means the
surety would stand in the shoes of the contractor to collect the contract
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complete the work. The owner or contractor would not be allowed to
reap a windfall by sticking the surety with the cost to complete. This
is similar to a concept where your insurance company would stand in
your shoes if it paid a loss and sought to recover and be reimbursed for
the loss caused by a third party. The ultimate issue here is whether the
surety was a volunteer in paying the money or actually took over the
SURMHFWDQGWKHUHIRUHDVDPDWWHURIIDLUQHVVVWDQGVLQWKHVKRHVRIWKH
contractor entitled to the contract proceeds. This will require a factual
determination to be made by the court and the court will look for
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but actually took over the work of the contractor. Important factors
include whether the surety asked that the payments be made directly
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DVVLVWDQFH WR WKH FRQWUDFWRU OHDYLQJ WKH FRQWUDFWRU LQ FRQWURO RI WKH
ZRUNDQGZKHWKHUDQ\FRQGLWLRQVRIGHIDXOWXQGHUWKHFRQWUDFWRUWKH
ERQGZHUHPHWLQGLFDWLQJLQYROXQWDU\WDNHRYHU
Michael J. Baker, Esq., is a partner in the Cerritos, Calif.-based law firm
of Atkinson, Andelson, Loya, Ruud & Romo. He is an expert in design and
construction contracts, mediation, and litigation. Please send him your
legal questions via e-mail at [email protected].
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A K E E S A F E T Y C O M PA N Y
Request a Free Catalog
888-724-2323
www.LNAsolutions.com/ICC
July 2013
Structural Engineer
25
EQFGUKORNG
Section 1604.8 – Anchorage
By ICC staff
1604.8.1 General. $QFKRUDJHRIWKHURRIWRZDOOVDQGFROXPQVDQGRI
ZDOOVDQGFROXPQVWRIRXQGDWLRQVVKDOOEHSURYLGHGWRUHVLVWWKHXSOLIW
and sliding forces that result from the application of the prescribed
loads.
1604.8.2 Walls. :DOOV VKDOO EH DQFKRUHG WR ÁRRUV URRIV DQG RWKHU
structural elements that provide lateral support for the wall. Such
anchorage shall provide a positive direct connection capable of resisting
WKH KRUL]RQWDO IRUFHV VSHFLÀHG LQ WKLV FKDSWHU EXW QRW OHVV WKDQ WKH
PLQLPXPVWUHQJWKGHVLJQKRUL]RQWDOIRUFHVSHFLÀHGLQ6HFWLRQ
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or cavity walls shall be embedded in a reinforced grouted structural
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DQGIRUHDUWKTXDNHGHVLJQUHTXLUHPHQWV
Q: Does the minimum anchorage force also pertain to interior non-loadbearing partitions that are not subject to wind forces?
A: <HV,IDZDOOUHTXLUHVDÁRRUURRIRURWKHUVWUXFWXUDOHOHPHQWIRU
ODWHUDOVXSSRUWWKHZDOOPXVWEHDQFKRUHGWRVXFKVXSSRUWLQJPHPEHUV
LQ DFFRUGDQFH ZLWK 6HFWLRQ 7KLV SURYLVLRQ LV LQWHQGHG WR
provide a minimum level of anchorage for walls irrespective of their
type or location.
A: No. Drilled mechanical or epoxy anchors may be used for wall
DQFKRUDJH+RZHYHUWKHHQJLQHHULVUHTXLUHGWRGHVLJQDQGGHWDLOWKH
DQFKRUDJHVRWKDWLWFDQSURYLGH´DSRVLWLYHGLUHFWFRQQHFWLRQFDSDEOH
RI UHVLVWLQJ WKH KRUL]RQWDO IRUFHVµ 7KLV PD\ SUHFOXGH WKH XVH RI
mechanical and epoxy anchors that have been shown by tests to not
perform effectively under seismic loading. The intent is that the anchors
be placed or detailed such that the reinforcing steel intercepts the failure
FRQH RI WKH DQFKRUDJH RU WKH FRQQHFWLRQ VKRXOG EH GHWDLOHG WR VKRZ
an effective load path through the reinforcing steel. Adhesive anchors
available commercially may also be considered acceptable for this
application if they have undergone a special seismic test and comply
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0DVRQU\(OHPHQWVµ$&
6HFWLRQUHIHUHQFHV6HFWLRQRI$6&(ZKLFKDSSOLHV
only to buildings in Seismic Design Category A. Refer to sections 12.11
DQGRI$6&(IRUJHQHUDOUHTXLUHPHQWVIRUDQFKRUDJHRI
structural walls.
These questions and answers are from the 2009 IBC Q&A Structural
Provisions. The questions are commonly asked questions which arise in the
application of code provisions during design and plan review.The 2009 IBC
Q&A Structural Provisions is available at iccsafe.org/store. Use ID # 4003S09.
The applications published herein are those of the ICC staff and are not
binding on the authority having jurisdiction. The authority having jurisdiction
has the ultimate responsibility for rendering interpretations of the code.
Q: Section 1604.8.2 requires a minimum level of anchorage of concrete
and masonry walls to roofs and floors that provide lateral support for
the wall. Does this section preclude the use of drilled mechanical or
epoxy anchors?
Editor’s note: In 2013, Code Simple will reproduce parts of “2009 IBC Q&A – Structural
Provisions,” which is a compilation of questions on the structural provisions of the code and
answers provided by International Code Council staff. Upcoming issues will include additional
Q&As on the 2009 IBC. We believe that this will be of interest to and benefit our readers.
26
Structural Engineer
July 2013
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July 2013
Structural Engineer
27
UVTWEVWTCNCTEJKVGEVCPFGPIKPGGT
Dynamic structures
By Ciro Cuono, P.E., LEED AP and Michael Wyetzner, AIA, LEED AP
Structural engineer
'\QDPLF RU NLQHWLF DUFKLWHFWXUH LV DOO DURXQG XV 'RRUV ZLQGRZV
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VWRUDJHV\VWHPVHWFDUHDOOVLPSOHH[DPSOHVRIPRYLQJDUFKLWHFWXUH
DOEHLWRQDVPDOOVFDOH2QDODUJHUVFDOHPRYDEOHDQGEDVFXOHEULGJHV
DQGPDQ\VSRUWVVWDGLXPVZLWKUHWUDFWDEOHURRIVDUHPRUH´VWUXFWXUDOµ
H[DPSOHV ZLWK PXFK ODUJHU DQG VLJQLÀFDQW PRYLQJ SDUWV 6WUXFWXUDO
engineers are often attracted to their craft because of a keen interest in
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DQGDUFKLWHFWXUHKRZHYHUFDQKDYHDSRZHUIXOHIIHFWRQRXUEXLOGLQJV
6LPSO\SXWZHSUREDEO\FRXOGQ·WIXQFWLRQZLWKRXWVRPHPRYLQJSDUWV
We have had a few opportunities to be involved with projects with some
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RQSLVWRQVDQGUHVWRUDWLRQRIDKLVWRULFJDWHRQDVLPSOHSXOOH\V\VWHP
Other examples include movable bleachers and rotating platforms at
some restaurants with interesting views.
There have been precedent projects involving revolving or rotating
KRXVHVVXFKDVWKH)RVWHUKRXVHLQ:LOWRQ&RQQ,QPRUHUHFHQW\HDUV
'DYLG)LVKHURI)ORUHQFH,WDO\KDGSURSRVHGDQH[WUHPHH[DPSOHLQDQ
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Velarium was installed with ropes and pulleys and tied to the heavy
masonry to protect spectators from the hot Roman sun. It is believed
that it was operated by sailors experienced with the ropes and winches
on ships. The Velarium was not different in concept from retractable
roofs in modern sports stadiums.
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the effects of dynamic loads and the increased complexity of the analysis
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the tendency to be stronger under dynamic or short-period loading. The
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requires the analyst to determine the worst case of loading.
28
Structural Engineer
July 2013
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to most structural engineers but more the realm of specialists.
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their name from the drafting instrument. A simple example is a vertical
lift or genie lift. With a push of a button the scissor trusses are raised
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This ability to deploy a structure from a compact form has lent the
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and an inspiring read for kinetic architecture.
Architect
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devices have long been used in industrial architecture to respond to and
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environment and become a great piece of architecture.
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In the closed position they protect from the severe weather of the Florida
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direct result of these dynamic panels.
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like metal apertures dilate and contract to control the quantity of sunlight
admitted through a curving glass curtain wall along the Seine. From the
interior these form a silhouetted screen against daylight. Reminiscent of
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the-art in solar technology. Today’s solar technology is capable of tracking
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uses movement to shield the sun and create sensation. A brise soleil
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allowing the outdoors in.
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disrupted. Discombobulated. Transformed. As David Greene of Archigram
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effective transformation of the space and the perceived metamorphosis.
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employing sliding walls to shift architectural perceptions into the fourth
dimension where time became an element in the experience of the spaces.
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shifting orientation and the experience of the room for the diner.
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perception and technology transform all buildings into the realm of the
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Ciro Cuono, P.E., LEED AP, is a principal at Cuono
Engineering PLLC, Port Chester, N.Y. He can be reached
at [email protected]. Michael Wyetzner,
AIA, LEED AP, is a partner at Michielli + Wyetzner
Architects, New York. He can be reached at mwyetzner@
mwarch.net.
July 2013
Structural Engineer
29
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2013 Best Firms To Work For
By Christina M. Zweig
The 2013 Best Firms To Work ForDZDUGUHFRJQL]HV$(3DQGHQYLURQPHQWDO
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Winners of this year’s Best Structural Engineering Firms To Work For
set themselves apart from their peers through superior leadership and
the careful creation of an environment that allowed every individual to
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2013 Best Firm to Work For²Structural Engineering
Place Winners
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30
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Barrish Pelham & Associates, Inc.
14
Sacramento, CA
2
ARW Engineers
22
Ogden, UT
3
Huckabee
88
Fort Worth, TX
4
Douglas Wood Associates, Inc.
14
Miami, FL
5
Hinman Consulting Engineers, Inc.
26
San Francisco, CA
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Structura, Inc.
11
Rockville, MD
7
Ehlert/Bryan, Inc.
34
McLean, VA
8
Bracken Engineering, Inc.
33
Tampa, FL
9
Simpson Gumpertz & Heger Inc.
453
Waltham, MA
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leading to many changes and improvements in all aspects of the operation.
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exactly where the company was going and what their individual roles
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with new clients. Other technological changes led to improvements
in connectivity such as the use of collaborative meeting technology
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provided with tablets and smartphones with unlimited texting and Internet
capabilities to ensure greater communication and telecommuting abilities.
The renewed optimism was celebrated in other ways as well. For
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that has historically led to staff being promoted to principal roles.
10
Mulhern & Kulp Structural Engineering Inc.
30
Ambler, PA
11
Baldridge & Associates Structural
Engineering, Inc. (BASE)
24
Honolulu, HI
Employees are encouraged and rewarded for speaking up regarding
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Reaveley Engineers + Associates, Inc.
31
Salt Lake City, UT
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Structural Engineer
July 2013
The Structural Engineer Professional Development Series offers structural engineers a QUICK and FREE
way to earn continuing education credit by reading specially focused articles and taking an online quiz.
The following Professional Development Series articles are
currently available online at http://continuingeducation.zweigwhite.com:
s BIM Enhances Structural Analysis Regardless of Project Size
s Thin Slab Floor Systems for High Rise Towers
s Guidelines for Development around Tunnels and Seismic Compliance
of Underground Structures
s The Design of Fiber Reinforced Composite Materials for Strengthening of Existing Structures
s Energy Analysis That Fits Your Building Project
s New Seismic Stabilization Technology for Retrofits and New Construction
s BIM in a Cloud II: BIM and Cloud Computing for Structural Engineering
s Differential Shortening of Tall Steel Building Columns
Slender Column Design
Based on ACI 318-08
By Mahmoud E. Kamara, Ph.D., and Lawrence C. Novak, S.E., SECB, LEED AP
The design of fiber reinforced
composite materials for strengthening
By Sarah Witt
of existing structures
For online access to all of
Structural Engineer PDH
articles, visit
http://continuingeducation.
zweigwhite.com
Energy Analysis That Fits Your
Building Project
By Jeff Yoders
October 2011
Sponsored by
JANUARY 2010
Content by
MARCH 2011
®
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Sponsors of the Structural Engineer
Professional Development Series
ZweigWhite is registered with the AIA Continuing Education System (CES) and is committed to developing quality learning
activities in accordance with CES criteria. ZweigWhite is also registered with the Florida Board of Professional Engineers.
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educational program that provides a ground-level education for
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of a new employee evaluation process.
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meetings and brainstormed for new ideas on how to increase the
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time employees.
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the company website to create an inviting feel. Staff photos were taken
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hours of time to help teams in their post-earthquake assessments.
32
Structural Engineer
July 2013
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employees. At this meeting CEO Chris Huckabee shares the strategic
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Best Firms – Architecture
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set apart from their peers through superior leadership and the careful
creation of an environment that allowed every individual access to their
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ranking showed an exceptional dedication to giving their employees the
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knowledge and give back to the community.
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service. Huckabee has a community outreach committee made up of
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without having to use vacation or sick time. Huckabee also has an
impressive summer internship program and a community excellence
fund.
2013 Best Firm to Work For²Architecture
Place Winners
1
Davis Bews Design Group, Inc.
Employees HQ
20
Oldsmar, FL
2
Huckabee
88
Fort Worth, TX
3
English + Associates Architects
16
Houston, TX
4
Randall-Paulson Architects, Inc.
23
Roswell, GA
5
M.C. Harry & Associates, Inc.
27
Miami, FL
6
FreemanWhite, Inc.
108
Charlotte, NC
7
Walcott Adams Verneuille Architects
13
Fairhope, AL
8
OPN Architects, Inc.
83
Cedar Rapids, IA
9
FRCH Design Worldwide
218
Cincinnati, OH
10
Lionakis
178
Sacramento, CA
11
Sillman Wright Architects
11
San Diego, CA
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KSQ Architects
69
Tulsa, OK
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month there would be a surprise gift or activity for employees.
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Huckabee coaching program added some new coaches and restructured
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to establishing a genuine partnership with their clients through exciting
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contributes to their success.
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Structural Engineer
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commitment and teamwork.
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to all ideas and give our undivided attention when discussing these ideas.
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either has been made. Sincerity: We will always be ourselves and always
be true to our own personalities. Commitment: We will do whatever it takes
to get the job done on time. Teamwork: We will assist one another when
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employees’ individual development plans quarterly to incorporate their
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but are encouraged to participate in setting and achieving those goals.
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employees. Our culture enables all employees to work as a team on the
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basis. We sponsored an Earth Day event for our employees and clients.
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34
Structural Engineer
July 2013
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Barrier-Bac protects middle
school from sub-grade
moisture transmission.
May 2013, the floor was finished and buildings were constructed.
Project: Sossaman Estates Middle School
Location: Gilbert, Ariz.
Architect: Hunt & Caraway Architects, Phoenix, Ariz.
Structural engineer: Beauchamp Engineering, Phoenix, Ariz.
General contractor: CORE Construction
Concrete subcontractor: Sun Valley Masonry
Product distributor: AMW Construction Supply, Phoenix, Ariz.
Product: Barrier-Bac VB-350 16 mil vapor barrier, manufactured by Inteplast Group Ltd.
Sixty-six classrooms DQGFXELF\DUGVRIFRQFUHWHDUHEHLQJSURWHFWHG
from sub-grade water vapor moisture transmission with Barrier-Bac
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chose Barrier-Bac’s product due to its extremely low water-vapor
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Sossaman Estates Middle School designers had the highest quality
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January 2013, Barrier-Bac VB-350 was applied on top of “sub-grade”.
The key to building and maintaining an excellent polished slab-on-grade
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high-performance moisture vapor barrier between the sub-grade and the
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vapor moisture migrating from the sub-grade.
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January 2013, all the penetrations were well sealed before concrete pouring.
36
Structural Engineer
July 2013
Superior
S
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APR 2012
VBC-350 / 31 mil
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EQFGU+$%
Structural changes in the 2012
International Building Code
Part I of this two-part article provides a brief overview of the more significant
changes to Chapter 16 of the IBC, which covers design loads for structures.
By John R. Henry, P.E.
About 100 successful code changes to the structural provisions of the
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into the current 2012 edition of the IBC. The 2012 edition of the
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The main structural standards referenced in the 2012 IBC for loads
and materials are shown in the following table.
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Key referenced structural standards in the 2012 IBC
Subject
1
2
38
IBC Chapter Referenced Standard in 2012 IBC
Structural loads
16
ASCE/SEI 7-10
Concrete
19
ACI 318-11
Aluminum
20
ADM1-2010
Masonry
21
TMS402-11/ACI 530-11/ASCE 5-11
TMS602-11/ACI 530.1-11/ASCE 6-11
Structural Steel
22
AISC 360-10
AISC 341-10
Cold-formed steel
22
AISI S100-07/S1-101
Wood
23
AWC NDS-2012
AF&PA SDPWS-082
See Chapter 35 for complete list of AISI standards referenced in the IBC.
Same as 2009 IBC (no change in 2012).
Structural Engineer
July 2013
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and to coordinate the terminology with ASCE 7-10.
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implies something about the nature of the building occupants and
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structures regulated by the IBC and IEBC are not even occupied but
are assigned an occupancy category because their failure could pose
a substantial risk to the public.
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Section 1605, Load Combinations. The strength design and allowable
stress design load combinations in the 2012 IBC have been coordinated
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for ice-sensitive structures. These sections reference ASCE 7 Section
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Design & investigation
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were deleted from the code and replaced with a reference to similar
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Figure 1. Approximate Relationship between Number of Lives Placed at Risk by a Failure
and Risk Category (Courtesy of ASCE, ASCE 7-10 Commentary Figure C1-1).
Section 1605.2, Load Combinations Using Strength Design or Load and
Resistance Factor Design. The wind design requirements of Section
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account for the new strength level wind forces in ASCE 7-10.
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both the basic and alternative basic ASD load combinations to account
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Table 1607.1, Minimum Live Loads. 0DQ\OLYHORDGVLQ&KDSWHURI
ASCE 7 were updated in the 2010 edition of the ASCE 7 standard.
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live loads prescribed in IBC Section 1607 and Table 1607.1 have
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code were deleted because they were incorporated into ASCE 7-10.
40
Structural Engineer
July 2013
Section 1607.6, Helipads. The terminology and live load design
requirements for helicopter landing areas have been updated and
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of helicopters. The previous provisions were unclear as to whether or
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criteria required to design helipads were updated and coordinated with
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Section 1607.7, Heavy Vehicle Loads.3URYLVLRQVUHODWLQJWRWKHGHVLJQ
RI VWUXFWXUHV VXSSRUWLQJ KHDY\ YHKLFOH ORDGV LQ H[FHVV RI pounds gross vehicle weight have been updated. Structures intended
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parking garages. Changes were also made to loading requirements
for forklifts and movable equipment.
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is impounded upon and the primary drainage system is blocked.
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per foot or greater toward points of free drainage are not considered
susceptible and need not be designed for ponding.
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John R. Henry, P.E., is the principal staff engineer, International Code Council. Contact him at
[email protected].
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EQPETGVG
‘Prognosis Negative’
Like in the fictional movie, it is clear that careful attention
to details and proper diagnosis of the issues at hand will
minimize risk, as well as long-term consequences.
By Chris Gray, P.E.
You may have KHDUG ´3URJQRVLV 1HJDWLYHµ UHIHUHQFHG LQ WKH SRSXODU
´6HLQIHOGµWHOHYLVLRQVHULHV´3URJQRVLV1HJDWLYHµUHIHUVWRDÀFWLRQDO
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in fact developed a script of the concept. According to Terry Gross of
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Concrete cores for investigative testing.
:KLOH /DUU\ 'DYLG PRVW DVVXUHGO\ PHDQW WKH VFULSW WR EH D FRPHGLF
SDURG\ RI KLV RZQ OLIH HYLGHQFHG E\ WKH ´&XUE <RXU (QWKXVLDVPµ
VHULHVWKHFRQFHSWSUHVHQWHGRIIHUVDQLQWHUHVWLQJFKDOOHQJHWKDWPDQ\
of us face in our lives.
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XSIURQWULVN":HFRQIURQWWKLVTXHVWLRQLQRXUSURIHVVLRQDOZRUOGVDV
well as our personal lives.
,QWKHSURIHVVLRQDOFRQWH[WRISDUNLQJPDQDJHPHQWWKH%HUNV&RXQW\
3DUNLQJ*DUDJHSUHVHQWVDQLQWHUHVWLQJORRNDWKRZWKLVGLOHPPDUHODWHV
to the construction industry.
7KH &RXQW\ RI %HUNV UHFRJQL]HG WKH FULWLFDO QHHG WR HYDOXDWH WKHLU
20-plus-year-old parking structure properly. The garage’s condition had
deteriorated over the years due to lack of proper attention. To evaluate
WKH VWUXFWXUH SURSHUO\ WKH &RXQW\ UHWDLQHG D SDUNLQJ H[SHUW IDPLOLDU
ZLWKQHZFRQVWUXFWLRQDQGUHVWRUDWLRQRISDUNLQJVWUXFWXUHVQRWXQOLNH
a patient seeking a medical specialist to diagnose and treat him or her
for a unique condition.
Accurate diagnosis and treatment of any disease would not be
possible without thorough testing and investigative work. The parking
expert implemented concrete testing to evaluate chloride levels in
WKH FRQFUHWH VLPLODU WR D SK\VLFLDQ FKHFNLQJ D SDWLHQW·V FKROHVWHURO
levels. High chloride levels in concrete result in corrosion of steel
UHLQIRUFHPHQW ZKLFK LV WKH OLIHEORRG RI FRQFUHWH $GGLWLRQDOO\
the owner implemented petrographic testing to determine existing
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FRQWHQW $V D FRPSDULVRQ SK\VLFLDQV PXVW XQGHUVWDQG D SDWLHQW·V
previous medical history to know what to recommend and treat him or
her effectively.
42
Structural Engineer
July 2013
Pachometer reading near column.
Investigative pit near column.
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39. CONTINUOUS BEAM ² THREE EQUAL SPANS ² ALL SPANS LOADED
Figure 1: Table 3-23, AISC Steel Construction Manual Thirteenth Edition, 2006.
7KH SDUNLQJ VSHFLDOLVW WRRN SDFKRPHWHU UHDGLQJV ZKLFK DUH 2. 3HWURJUDSKLFUHVXOWVLQGLFDWHGPLFURFUDFNLQJLQWKHWRSLQFKRI
HVVHQWLDOO\;UD\VRIWKHFRQFUHWHWRGHWHUPLQHWKHGHSWKRIHPEHGGHG
the concrete surface. Micro-cracking is a channel for chlorides to
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membrane bridges these micro-cracks and prevents chlorides from
SHQHWUDWLQJLQWRWKHFRQFUHWHVXUIDFH&KDSSHGOLSV"8VHFKDSVWLFN
Investigative testing would be for naught without the ability to
to provide a protective coating over your lips and prevent further
understand and relate the results of the testing to assess the causes
cracking and/or blistering.
and determine the remedies of any issues discovered. In the case of
WKLVSDUNLQJJDUDJHWKHUHVXOWVRIWKHWHVWLQJFRQÀUPHGWKHIROORZLQJ 3DFKRPHWHU UHDGLQJV DQG WHVW SLWV FRQÀUPHG WKDW VWUXFWXUDO
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structural reinforcement is necessary to support the structure
of chlorides is critical to the longevity of the structure. Using nonchloride containing de-icing chemicals such as sodium acetate
SURSHUO\ DQG DYRLG RYHUVWUHVV %DFN VWUDLQ" 6WUHQJWKHQ PXVFOHV
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around the strained area.
preventing chlorides from penetrating the concrete’s surface with
DWUDIÀFGHFNFRDWLQJPHPEUDQHSURYLGHVIDLOVDIHSURWHFWLRQ+LJK
FKROHVWHURO"&XWWKHIDWRXWRI\RXUGLHW
44
Structural Engineer
July 2013
Having accurate information is necessary to provide an accurate
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DOO FRQFUHWH WHVW UHVXOWV VSHFLÀFDWLRQV DQG FRQVWUXFWLRQ GUDZLQJV
This information assisted the parking expert in providing an accurate
assessment of the repairs.
7KLVLVHYLGHQFHGE\WKHRYHUVWUHVVH[KLELWHGLQWKHÀOLJUHHEHDPV7KH
overhead cracking at midspan beam locations may have been assessed
by an engineer as the result of normal deterioration from corrosion.
+RZHYHUE\H[DPLQLQJWKHEHDPVFKHGXOHVRQWKHDVEXLOWGUDZLQJV
FORVHO\WKHSDUNLQJH[SHUWGLVFRYHUHGWKDWPDQ\RIWKHEHDPVZHUH
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too low) helped assess the true cause of overstress of the beams.
With the top reinforcement installed to a lower elevation than
GHWDLOHGWKHÀOLJUHHEHDPVZHUHWDNLQJDUHGXFHGQHJDWLYHPRPHQW
DQGWKHUHE\FDXVHGDQLQFUHDVHGSRVLWLYHPRPHQWZKLFKRYHUVWUHVVHG
the existing reinforcement at the midspan. Had this issue not been
“How can we
avoid long-term
consequences while
minimizing our
upfront risk? We
confront this question
in our professional
worlds as well as our
personal lives.”
SURSHUO\HYDOXDWHGZLWKWKRURXJKLQYHVWLJDWLYHZRUNWKH&RXQW\PD\
very well have paid for repairs that would have failed to address the
root cause of the failure.
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VXSSOHPHQWDOUHLQIRUFHPHQWLQFUHDVHGWKHQHJDWLYHPRPHQWFDSDFLW\
and relieved overstress of the beams.
6RSHUKDSVZHFDQFDOOWKHDERYHSKHQRPHQRQD´3URJQRVLV1HJDWLYHµ
moment.
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GLDJQRVLVRIWKHLVVXHVDWKDQGZLOOPLQLPL]HRXUULVNDVZHOODVORQJ
term consequences.
Chris Gray, P.E. serves as a project manager for Timothy Haahs & Associates, Inc. (TimHaahs)
in the firm’s Philadelphia area headquarters. Gray specializes in the project management
and design of complex parking and mixed-use structures, as well as condition appraisal and
restoration of structured parking.
^ƚƌƵĐƚƵƌĂů^ŽŌǁĂƌĞĞƐŝŐŶĞĚĨŽƌzŽƵƌ^ƵĐĐĞƐƐ
Ő
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July 2013
Structural Engineer
45
URGEKſECVKQPUQHVYCTGIWKFG
Steel foundations
Metal Foundations’ patented steel foundations are an
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Grove Products, Inc.
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S-FRAME Software Inc.
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Geopier Foundation Company
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46
Structural Engineer
July 2013
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48
Structural Engineer
July 2013
TGCFGTTGUQWTEG
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July 2013
Structural Engineer
49
VJGXKGYHTQOJGTG
Engineering, history and civilization
By Richard G. Weingardt, P.E.
A favorite adage XVHGE\WKRVHZKRSRQWLÀFDWHDERXWWKHJUHDWQHVVRI
RXUSURIHVVLRQLVWKLV´7KHKLVWRU\RIHQJLQHHULQJLVWKHYHU\KLVWRU\RI
FLYLOL]DWLRQµ
This statement has always seemed grand and inspiring to me. Yet few
structural engineers are well versed on the actual impact engineering
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that affect everyone’s standard of living.
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the media simply prefers to give full credit and accolades to architects
IRUDQ\H[WUDRUGLQDU\EXLOGLQJRUVWUXFWXUDOHQJLQHHULQJDFKLHYHPHQWV²
or credit scientists if an engineering feature has a technical breakthrough
attached to it. And when the media compiles lists of pacesetters and
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Yet engineers are the single most indispensable group needed for
developing and maintaining any country’s infrastructure and standard
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PRYHUV DQG VKDNHUV DURXQG XV ,QVWHDG RI EHLQJ SHUFHLYHG DV ´WKRVH
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are unlike other groups whose members dominate public and societal
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achievements and discoveries uplift the human spirit! Think of the
much-admired Eiffel Tower or Golden Gate Bridge. Engineering is the
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conceded that the engineer must take his [or her] proper place in society as
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This is more true today than it was then.
50
Structural Engineer
July 2013
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history of the profession and don’t care to understand what went before
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membership support requiring additional education in leadership and
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and public administration. The remaining portion of their time would
be left to concentrate on learning advanced engineering subjects. But
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What a shame!
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encouraged to step forward with a plan.
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Richard G. Weingardt, P.E., is CEO and chairman of Richard Weingardt
Consultants, Inc., a Denver-based structural engineering firm. He can be
contacted at [email protected].
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PUBLISHING

Shankar Nair has engineered bridges and buildings that

Transcription

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