Top 5 Excel Resources...Plus Two More

If you search the web for Excel resources, it's often overwhelming (/frustrating) to navigate the slew of results that come back. "133 Excel Tutorials!" "50 Excel Shortcuts!"

In my ongoing quest to develop great Excel workbooks, here are the sites I seem to end up at again and again.


The tag line pretty much says it all: Become Awesome at Excel.


It's almost inevitable that you'll end up here if you're trying to figure out Excel charts.

The Spreadsheet Guru

A blog with some great excel tips. I tend to scroll through and think..."I want to know that!...and that!...and that!" It's click baiting for nerds.

StackOverflow and SuperUser

When you've Googled the heck out of your problem to no avail, head to these two StackExchange sites. Users collaborate to ask and answer questions, and literally thousands of Excel (SuperUser) and Excel VBA (StackOverflow) questions are archived here.

Chip Pearson

A great index of topics -- a fun way to figure out how just how much you don't know about Excel.

And now just for fun...


This one's for the day when you're feeling a bit quirky. Some of the posts I enjoy the most cover graphical expression of mathematical equations.


An online TV channel for Excel. 'Nough said. (*fistbump* ... *straightens pocket protector*)

If you know of a great Excel resource that's not listed above, add it to the comments!


As I noted in last week's newsletter (subscribe, and you too can be privy to exclusive content!) I'm pretty darn enthusiastic about the #ILookLikeAnEngineer Twitter extravaganza.

It struck me as a joyous coming together of outliers. A celebration of uniqueness, and a grasping for the empowerment so hard won by our grandmothers which too often we leave unclaimed. I felt...exultant seeing all the tweets come in. I felt proud to be an engineer, proud to be a femgineer.

Then, over breakfast, a friend and I got to talking. He is also an engineer, but to my surprise and chagrin he was pretty emphatically not a fan of the hashtag avalanche. Partly, his extremely literal nature had his hackles up - "But she doesn't look like an engineer, she looks more likely to be a model!" In marked contrast to my gut reaction, his instinct was to feel that women were asking for special acknowledgement and treatment. Personally, I think this speaks more to one too many sensitivity trainings and a general suspicion of advertising, rather than anything that might be termed misogyny. But I do wonder how many people out there felt the same way.

If I were being finicky over diction, I might have recommended #IAmAnEngineer instead. I think this would have significantly increased my friend's receptiveness. Myself, I would have loved it with equal fervor.

Semantics aside, I don't look like an engineer. (Actually, I don't know that I look like much of anything distinctive other than a female of the species.) When we say, "she looks like ______." we're fundamentally talking about conformance to stereotypes. Which is to say, unless you're a white male rockin' 1960s NASA Mission Control style, you probably don't "look like" an engineer.

Not that I'm dismissing the reactions to that OneLogin ad and everything that followed. Far from it. The gender gap in engineering is very real. And yes, that is probably due in large part to external social forces. But for every force there must be an equal and opposite reaction, lest we be pushed about at the whims of others. Like Isis Wegner, I imagine every female engineer has a story where they were made to feel "less than" specifically because of their gender. I've walked out of job interviews knowing my ovaries had put me out of the running, left meetings feeling like my voice meant less because I'd decided to wear a dress.

But I could have pushed back. Perhaps I should have pushed back. After all, it is a truism that no one can make you feel powerful without your consent.

Let's hold on to some of the power and pride we felt on August 3rd, 2015.

Sadly, the half-life of Twitter is astonishingly short, and I fear #ILookLikeAnEngineer is already a dwindling blip on the social media radar. But I'm hoping against hope that it will be the pebble dropped in a pond, the butterfly flapping her wings in a BART station, stirring waves and winds of change.

Postscript: I had a tough time finding the right words for this one, and I didn't 100% capture my tangle of thoughts on the present/future of women in engineering. So feel free to keep the conversation going in the comments!

An Ode to Statics


Thy name is statics.

A trinity of stillness

In that most fundamental rule of three.

Sigma F sub x to zero.

Sigma F sub y to zero.

Sigma M sub z to zero.

Faced with an FBD most tortuous,

Fear not - the forces ever balance.

Tip to tail and tail to tip,

The vectors point the way,

Toward stillness at all nodes.


Thy name is statics.

A Covered Bridge Turns 50

If you happen to be in Champaign, Illinois tomorrow, you can celebrate the 50th anniversary of the Lake of the Woods Covered Bridge. It strikes me as a testament to small-town America that this modest bridge is getting a party in its Jubilee Year.

Image Credit: Steven Severinghaus (Creative Commons)

Image Credit: Steven Severinghaus (Creative Commons)

The bridge was designed by University of Illinois Professor German R. Gurfinkel, and construction began in 1965. Eighteen months and $55,000 later, a new covered bridge stretched 140 ft. across the Sangamon River. The bridge was constructed of southern pine, Douglas fir...and steel girders.

That's the little secret of this picturesque covered bridge. It's not...technically...a covered bridge. Rather, it's a steel stringer bridge with a faux wooden Pratt through truss on top. According to FHWA guidelines, that ixnays it as an "authentic" covered bridge.

Image Credit: Gary Jazz (Creative Commons)

Image Credit: Gary Jazz (Creative Commons)

As I've mentioned before, I love bridges because all the engineering is on display, and it nettles me when a bridge pretends to be something it isn't.

Still, why do I care? Isn't "covered bridge" as much a visual aesthetic as a structural system?

And the truth is, when I visited the bridge a couple years ago, I didn't care at all. It fits in beautifully with its surroundings, is an icon of the park, and complements the nearby Museum of the Grand Prairie. (Where, if you wait patiently, you can pretend to be an 1800s blacksmith - loads of fun.)

Ultimately, authentic or not, there's still something nostalgic and wonderful about strolling across a covered bridge on a crisp autumnal day.


10 Engineering Quotes to Live By

I'm in the mood for musing today so I thought I'd share the 10 quotes that most inspire me to become a better engineer, and keep me laughing when I fall short of perfection.


Theory is the language by means of which lessons of experience can be clearly expressed.
— Karl Terzaghi


Engineering is the art of modeling materials we do not wholly understand, into shapes we cannot precisely analyze so as to withstand forces we cannot properly assess, in such a way that the public has no reason to suspect the extent of our ignorance.
— Dr. A. R. Dykes


All models are wrong. Some models are useful.
— George E. P. Box


I am opposed to the laying down of rules or conditions to be observed in the construction of bridges lest the progress of improvement tomorrow might be embarrassed or shackled by recording or registering as law the prejudices or errors of today.
— Isembard Kingdom Brunel


The joy of engineering is to find a straight line on a double logarithmic diagram.
— Thomas Koenig


Scientists study the world as it is, engineers create the world that never has been.
— Theodore von Karman


I am an Engineer. I serve mankind by making dreams come true.
— Anon


As for earthquakes, though they were still formidable, they were so interesting that men of science could hardly regret them.
— Bertrand Russell


When engineers and quantity surveyors discuss aesthetics and architects study what cranes do, we are on the right road.
— Ove Arup


Perfection is achieved, not when there is nothing more to add, but when there is nothing left to take away.
— Antoine de Saint-Exupery

Need a Bridge? Just Press "Print"

Come 2017, the denizens of Amsterdam may be able to stroll across the most unique pedestrian bridge in the world - a bridge 3D printed in midair. The project is a collaboration between R&D startup MX3D, Dutch construction company Heijmans, and Autodesk.

Artist's rendering of the proposed 3D printed bridge (courtesy of MX3D)

Artist's rendering of the proposed 3D printed bridge (courtesy of MX3D)

According to this FastCompany article, the bridge will be approximately 24 feet in length, and will take just two months to print, though the exact location of the bridge has yet to be determined. The 3D printing method used by MX3D is entirely different from the traditional methods for metals. There's no printer bed here, no powder layers or lasers. Instead, the additive process appears to be a little bit like accumulating a million tack welds in a line. Robots with six-axis arms will start at either end of the bridge, printing both the bridge and their own rails as they move along. This method of fabrication raises some interesting questions as to what the material properties and behavior will be.

The sketches of the proposed bridge suggest that topology optimization is being used in the design. I won't pretend to understand the required mathematics, but my bare-bones understanding is that topology optimization can optimize material for a given load (often yielding non-intuitive solutions). This is similar to what I suspect Arup did when they optimized a steel node for a building - which to date is just about the only other application of 3D printing that I know of in Structural Engineering.

The art of structure is where to put the holes
— Robert le Ricolais
Sketches of the bridge concept (courtesy of MX3D)

Sketches of the bridge concept (courtesy of MX3D)

Joris Laarman is listed as the designer on the MX3D website. The Dutch artist graduated from Design Academy Eindhoven in 2003, founded Laarman Labs in 2004, and received the Innovator of the Year award from the Wall Street Journal in 2011. He has 3D printed works in resin, metal, and ceramic, with work on display at MoMA, V&A, and Centre Pompidou. While his work in 3D printing is impressive, the first question in my mind is..."but what about the structural engineers?!" It may well be yet another case of heaping public praise on the architect while the engineer is treated as a silent partner. At least, I hope it is. The project may have an undeniable 'cool' factor, but without a structural engineer involved it's hard to see it as anything more than an art project.

Autobots roll out! (courtesy of MX3D)

Autobots roll out! (courtesy of MX3D)

California I-10 Bridge Collapse

On Sunday, July 19 an end span of California bridge 56-0576R on I-10 over Tex Wash collapsed in a flash flood.

Built in 1967, the concrete slab bridge is 90 ft. long with three 30 ft. spans at a 10 degree skew. The bridge was identified as functionally obsolete (most likely indicating vehicle capacity was inadequate or the geometrics substandard) but was not listed as structurally deficient. In fact, according to, the 48-year-old bridge had received a good rating in a 2013 inspection. The overall sufficiency rating was 91.5/100, deck 6/9, superstructure 7/9, and substructure 7/9. Furthermore, the channel was described as stable.

So how did the bridge come tumbling down? Flash flood is likely the key word. The storm dumped 6.7 inches of rain on a county where the average annual rainfall is roughly 3 inches. The channel may have migrated toward the abutment during the flash flood, causing significant undermining and leaving the bridge foundation unstable.

Heading in to an El Niño year, this raises questions about the ability of California infrastructure to withstand increasingly extreme weather. According to the 2014 National Bridge Inventory, California has 25,406 bridges, with 2,501 identified as structurally deficient and 4,306 classified as functionally obsolete.

Interstate 10 serves as an important route between California and Arizona, and the economic impacts of this bridge failure are likely to be staggering. The collapsed eastbound structure typically carries in excess of 11,000 vehicles per day, roughly 40% of which are trucks. Granite Construction was hired to enact emergency repairs to the westbound bridge (namely, filling in the abutment undermining and placing tons of riprap). Granite also constructed crossovers that allow eastbound traffic to be diverted on to the westbound structure, with traffic resuming on Friday, July 24.

The cost to "rebuild" the eastbound bridge is estimated at $5 million, with $2 million of that coming from the Federal Highway Administration. I'm not entirely clear whether "rebuild" means "repair" or "replace". Caltrans' stated goal of September completion makes me think "repair", but then again, design of a workhorse bridge is fairly quick and history has shown that with financial incentives contractors can just about move mountains.


Four Favorite Bridges

Awhile back I was listening to the podcast Hello Internet when to my delight, the subject of favorite bridges came up. I thoroughly enjoyed listening to the hosts discuss their favorites, and based on the Twitter response to the episode, many other listeners did too.

For me, it raised the question - why do so many of us love bridges? Why the visceral response to the signature bridges of the world?

I’ve been asked many times why I like bridges and I’m generally a bit at a loss for words. I like bridges because…I love bridges! It’s just a gut-level fact. But when pressed to quantify my affection, I usually say that it’s because all the engineering is on display. The fundamental workings are right there for you to see, not hidden behind facades and bulkheads and aesthetic treatments as in our sister industry. If a bridge appears elegant, if it has “good bridginess,” I think it’s usually because the engineering itself is elegant.

I suspect there are also myriad intangible reasons for liking a particular bridge. The symbolism of connecting two disparate places. Memories of what we were doing and who we were with when we happened across a particular bridge. And surely each of us have a few special bridges where we recall the satisfaction of triumphing over design challenges.

In short, that podcast prompted me to create my own list of favorites (the only rule being that I had to have physically visited the bridge.) After racking my brain and whittling down my list I arrived at four favorite bridges.

Number 4. Lane Avenue Bridge - Columbus, Ohio, USA

This one I literally stumbled across while out for a long run with my best friend. It was the first time I encountered a cable-stayed bridge in the flesh, and I was infatuated. As a bonus, I was able to visualize the flow of forces and I'm always very excited when I can "read" a bridge.

Number 3. Multnomah Falls Bridge - Multnomah County, Oregon, USA

Try not to hold its association with the Twilight franchise against it. The Multnomah Falls bridge is elegance embodied, and it meshes with its environment in a way that definitely qualifies as "good bridginess". To heighten the pleasure of a visit, traverse the Historic Columbia River Highway (an engineering marvel in its own right) on your way to the bridge. You'll enjoy a leisurely drive dotted with waterfalls, sweeping vistas, and several other open spandrel concrete arch bridges.

Number 2. Auburn-Foresthill Bridge - Placer County, California, USA

Designed to accommodate a reservoir that never came to fruition, the Auburn-Foresthill bridge now soars 730 ft above the American River. It’s a special one for me because this seismic retrofit was the first major project I worked on. When I look at it, I’m immediately taken back to the camaraderie that came with grinding out 60 hour weeks, and the excitement of learning steel design.

Number 1. Millenium Bridge - London, England

It may be pedestrian of me, but I have a particular fondness for the Millennium bridge. It connects two place I enjoy - the Tate Modern and St. Paul's Cathedral. It recalls memories of my amazing study abroad trip to London. And while sometimes maligned, its "blade of light" aesthetic appeals to me, particularly when lit up at night. Finally and foremost, I love the story of its engineering. The snafu arising from the opening of the Wobbly Bridge was met with a focused "we can fix this" attitude. They researched, they tested, and they succeeded. (I also love that to generate randomized pedestrian vibrations for the final test of the retrofitted structure, a hoard of volunteers was told that free food was available at the other end of the bridge.)

For a great paper describing the retrofit, visit:

In Which We Make a Beginning

I’ve long mulled over ways to share my enthusiasm for bridges. Podcast? K-12 outreach?


I’m quite excited to finally be off the ground with a concept. There’s a paucity of bridge blogs out there and I hope this will become a collaborative space for practicing engineers, a resource for students, and pleasure reading for armchair bridge enthusiasts.

Building the website has been such fun (I’m particularly enamored with the logo) and my list of potential post topics is growing rapidly. With that said, feel free to contact me with any topics or topic categories you’d be particularly interested in reading about. (email: , twitter: @cablestay)

As for myself, I work as a bridge engineer in Lincoln, Nebraska in the United States. Accordingly, my perspective is likely to be a bit US centric. Hopefully this will make a nice complement to the wonderful UK based Happy Pontist blog, which – seriously – every bridge engineer should read.