Monthly Archives: May 2009

Walkabout

Had I little walkabout around my neighborhood on a beautiful afternoon. We have a couple of bridges nearby. A 120 foot prefab truss that replaced a cool home built suspension bridge. (flood damaged)

A couple of older railroad bridges. (nothing is that old in America)

And a fracture critical road bridge.


Bridge Papers

The Happy Pontist pointed to the University of Bath’s bridge conference. (I’m getting the feeling I should just point this blog toward the pontist and start working in the yard.)

The website presents 39 papers by engineering students, reviewing different bridges in terms of aesthetics, with some general structural calculations thrown in for good measure.

I read the paper on the Leonard P. Zakim bridge, by N. Vadgama and the one on the Saint Anthony Falls bridge, by T. THorp. Both well written papers with some interesting images that I had not seen before. One of the things I am trying to learn is exactly what the papers are attempting, how to develop a framework for judging the success of a structure. (aahhh what defines success)

As I am learning, writing an effective critique is difficult.

Design thoughts

Sitting in diversity training today, I was thinking bridge design thoughts.

  • how long, how wide, materials, which codes, location, project coordination, ASTM
  • staging, timeframe, costs, spans, profile, loads clearances, guardrail
  • joints, fixity, expansion, slenderness, strength, aesthetics, lights, conduit
  • barrier rails, construction sequence, plans, hydrology, drains, public meetings

You could add more but you get the idea. Design takes a lot of thought. Go here for pretty bridge pictures instead.

Writing a book

A few years back I wanted to publish a book of structural engineering problems to sell to students. So I bought a pack of 10 Internationa Standard Book Numbers (isbn) for $250 dollars and started a publishing company. The first book had a limited run of 50 copies which I sold through the local university bookstore.

I made all the books myself, utilizing a grill hot plate to make the glue melt on the cover and spine. (Somewhat like this but I used hot glue sticks) The books were a little bigger than paperbacks but had the same type of binding. I used one of my isbn numbers and volia, instant vanity publisher.

My second book was made by Blurb. Blurb has software that allows you to place images and text into predefined templates for publishing through their online service. Since I already had isbn barcodes, it was a simple matter of adding one and vanity book two was born. The great thing about my second book was that it was deemed worthy enough to make it into the Keosauqua library and my local university library collection.

The downside of using Blurb was the final version of the book resides on their system and I can only buy books through them unless I take the time to reformat the book. The next thing I am going to try is a service called Magcloud for publishing magazines.

Sunday Random thoughts

Some random thoughts on a beautiful Sunday morning.

Photo by kalleboo - flickr

Photo by kalleboo - flickr

  • Bridges need more dragons.
  • The Happy pontist spoke about habitable bridges. Imagine designing all the water and sewer pipes. (Interesting live loads)
  • Where are all the bridge design competitions in America? I can never find them.
  • What blogs do bridge engineers read? Do engineers read engineering blogs?
  • Who is the most famous living, working engineer? (behind Calatrava?) Name five.
  • Can an engineer be an artist?

It would be fun to have a round table discussion about what makes an engineer, an engineer and if engineers should be on the same level as architects (doctors?)…

Update: one more thought. Is it possible for an engineer to volunteer their engineering knowledge in their own country? Doctors and Architects volunteer but engineers?

Engineering Fee structure

Two things, I just started teaching the summer session of concrete design and I also have been working on concept statements for bridge repairs utilizing new stimulus funding. What do these things have in common? Well, in teaching, I try to interject real life situations into the class and one of them is how engineers will get paid for their work.

Chris Wise, from Expedition Engineering, (their website layout is just cool) wrote about fee structures for engineers in the new issue of “Building” (an online magazine)

Mr. Wise suggests that fees should be based on engineering talent and not on an some nebulous percentage of the project. He argues that agencies should be “commissioning designers in a way that knowingly selects them for their talent not for their convenience.”

I have the same dream but I can see how this is a problem. How do you then judge engineers on talent? As a firm you need jobs to develop your talent before you could “show” your talent. I agree the fee structure does not always select the best engineers and may discourage innovation.

Mr. Wise’s suggestion of a talent-based system would of course benefit his firm because of their cutting edge approach. But would they be the best value for a repair project? What is the best value?

I would love to work under a talent-based system (I have an ego) because it would mean the higher I reached as an engineer the more work I would get.

Expedition Engineering – finally cool engineers

I finally found a cool engineering company, with a Flash website and a blog!

Expedition Engineering does everything from engineering to planning, teaching, environmental, artistic and cultural projects. And bridges!
Lets see..I do,

  • engineering – check
  • teaching – check
  • environmental degree – check
  • Art – oil painting – check
  • cultural projects – hmmmm….does this site count? (www.engineeringforhumanity.org)
  • bridges – check

Successful like Expedition Engineering – well…I’m working on it…..

Keosauqua Bridge Successes & Failures

I don’t want to make this the Keosauqua 24 hour news channel but I would like to wrap it up with some of the success and failures. (Failure is a strong word, more like lost opportunities)

1) Success #1 – Public participation

I think the biggest success of the project was the strong public participation in the design. We had a number of public meetings, with great give and take discussions, along with a small bridge group that helped steer the details of the project. The bridge group would then spread the word throughout the community about what was happening with the bridge.

We also had a grand opening (inside because it was so cold) for the new bridge, with the Mayor, contractor, DOT staff and local citizens.

1) Failure – Building on success

The biggest “failure”, in my view,  was not utilizing all the expertise gained from this design on another project or using it as a springboard for new policies throughout our state. While this project was small in comparison to other bridges throughout the country it was really a new way of doing things. Allowing the designer to interact and work with the customer proved invaluable to the final design. Structural Engineers should be out there instead of just staying in the office and doing the calculations……

Continue reading

Bridge Lecture – World Steel Bridge Conference

I made the roster to give a talk on my last steel bridge design at the World Steel Bridge Symposium (WSBS), in November. I am also teaching concrete design this summer to third year civil and construction engineers.

My question is what makes a great lecture? I would really like to encourage, motivate and inform both groups but I am not sure I can. Is it possible to give a great talk to engineers? If I stress aesthetics, those engineers who favor economics will complain. If I focus too much on in-depth details I will put half the group to sleep and the other half will say I did it wrong.

I can’t really remember the last time I reallly enjoyed watching a lecture. What to do, what to do. Suggestions anyone?

Bridge Critique – Keosauqua Bridge Post #3

Back to the questions about the Keosauqua Bridge.

Was any effort made to reuse the existing pier positions by extending them sideways? It isn’t quite clear from the images so far.

The existing piers were not in the same locations as the new bridge piers. (The old piers were reused as revetment for the new bridge abutment slope protection and select stones were cut for the touch stones on top of the new piers. The touch stones allowed visitors to touch the “past” bridge. )

Any concern that the curved beam soffits makes it look like the bridge is a series of arches (especially in foreshortened perspective views), when structurally this is misleading?

Not until you mentioned it. (Ha!) It is a fair point, it depends on where you are located in relation to the bridge.  In this case the bridge has two prominent viewpoints.

One from the sides of the north abutment where people can play in parks and further downstream from the historic Manning Hotel.

This view is looking north on the upstream side. The girders look more like arches than haunched girders. (The touch stone are on top of the pier. Stones cut from the old truss bridge piers)

Continue reading

Bridge Critique – Keosauqua Bridge Post #2

I received some great questions about the last post that I think I should expand on, since I skimped on the reasons for the new bridge. (thanks for the questions by the way) I would have answered in a comment post but I wanted to add some images and frankly, I don’t know how to do that yet.

Given the width of footway provided on the new bridge, could the existing bridge have been retained as a footbridge?

Before replacing the truss bridge we evaluated whether or not it was possible to keep the old bridge in place, with one of the popular options being the use of the old bridge as a pedestrian bridge with a new vehicle bridge beside it. The problem essentially boiled down to money.

In 1937 the truss bridge was built on widened piers from the original 1873 bridge piers. Since we did not have any plans from that bridge it was difficult to determine the life left in the old limestone block piers and methods required to strengthen the piers would most likely rob them of their aesthetic appeal.

Continue reading