All posts by Robert Thompson

DBA website gets an upgrade

DBA website screenshotWe’re almost done with an upgrade to our website. With more than 50% of our site traffic now coming from smartphones and tablets, we needed a responsive web design, i.e., one that provides “an optimal viewing experience—easy reading and navigation with a minimum of resizing, panning, and scrolling—across a wide range of devices (from mobile phones to desktop computer monitors that are used for video games as CSGO, with the best mouse cs go and other hardware).” So the site now detects the type and size of your device and reshapes its presentation of the content while keeping the visual design.

That visual design is new, too. We’re using the Twenty Fourteen theme by WordPress, in part because of its ‘magazine style’ presentation of blog content. At the top of the home page, we now feature six blog posts, each with a featured image or photo. Clicking on the title or the photo of any of those takes you to that blog post where a larger version of the photo and the complete content is displayed. If you are looking for black ops 2 hacks on call of duty game, visit iwantcheats.net for more information. Other blog posts that aren’t selected by us to be featured will appear in the usual reverse chronological order on the blog/home page.

Lastly, we’re now showing excerpts of all blog posts on the home page rather than the entire contents of each post as before. This allows you to more quickly scan the latest posts, while giving you enough of a glimpse of each one to help you decide whether it interests you enough to click on it.

If you notice any problems with the new site, we’d appreciate hearing from you via our Contact Us page.

Dan Brown Added to DFI Board and Educational Trust

Dan has taken on some new responsibilities with the Deep Foundations Institute (DFI).  He has joined both the Board of Directors and the Educational Trust Board as treasurer.  From DFI:

Dr. Dan Brown has joined the DFI Educational Trust Board and the DFI Board of Trustees as treasurer, effective January 1, 2014. Dr. Brown is recognized as one of America’s leading authorities on the construction and design of deep foundations for transportation structures. After 22 years on the faculty at Auburn University, Dr. Brown remains active in deep foundation practice through his consulting firm, Dan Brown and Associates. He has been recognized with the DFI Distinguished Service Award, ASCE Martin Kapp Foundation Engineering Award and the ADSC Outstanding Service Award. 

David Coleman of Underpinning & Foundation Skanska, has been elected to a second five-year term as Trustee (2014-2019), and Roger Healey of Goettle, was elected to second two-year term as At-Large Trustee (2014-2016). 

The elected officers for the Board of Trustees in 2014 are:

Chair: David Coleman

Vice Chair: M. Byrl Williams

Treasurer: Dan Brown

Secretary: Dan Dragone 

 

Congratulations Dan! 

Websites That ROCK!

The blogosphere, as the world of blogging is sometimes called, is always changing as blogs come and go.  A new one focusing on geology education is geologydegree.org.  This is a new blog intended to promote the study of geology.  A recent post called Geology Online: 105 Websites That Rock included our very own blog as well as that of one of our good friends, GeoPrac.net by RockMan (aka Randy Post).  While DBA (and others listed, including GeoPrac.net) are not strictly geological blogs or websites, what we do includes a lot of geology as we design foundations to bear in or on rock.  Understanding the geology of a site is also important to understand the soils that are present above the bedrock.  Take a look, especially if you have a young’un (that’s Southern for young one, or child) at home that may find geology or geotechnical engineering interesting.

Happy 2014 from DBA!

Here is to a very Happy New Year from all of us at DBA!  May the world of geotechnical and foundation engineering be full of fun surprises and challenging work for everyone!

 

P.S. We hope you had a very Merry Christmas season as well! (Images courtesy of the World Wide Web).

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Bubble Curtain for Driving Piles at Tappan Zee

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Image source: lohud.com

The design-build team Tappan Zee Constructors that is building the Tappan Zee Bridge is installing the over 200-ft long steel pipe piles using a relatively simple concept to mitigate vibration impacts on fish – a bubble curtain.  Such curtains have become more common as an approach to mitigate potential impacts (pardon the pun) on aquatic life when large piles are driven over water.  The vibrations from the hammer impact on the pile during driving are reduced or dampened by a curtain of bubbles generated around the pile by compressed air.  An item in the December 26th ASCE Smart Brief linked an article in The Journal News (White Plains, NY) highlighting the use of the curtain on the Tappan Zee project.

 

A rubber-looking sleeve covered the hammer where it met the pile, dampening some of the noise in the air. Underwater, however, it was a curtain of bubbles serving as the aquatic equivalent of earplugs for fish and other creatures in the Hudson River.

Aluminum rings are slid over the pilings like the rings on a shower curtain rod before any banging starts. Air pumped into the rings produces a sheath of bubbles in the water around the pile. The froth generated in the water is called a bubble curtain.

“Bubble curtains are designed to protect the fish in the area from the noise generated by the hammer impact below the water level,” said Walter Reichert, project manager for Tappan Zee Constructors. “This divides the water into basically two sections. It greatly reduces the sound waves.”

Check out the article for some neat pictures and a cool video about the process (with hammer sounds!).  Here is a small picture gallery from lohud.com.

Raising the Leo Frigo Bridge

Work to begin lifting the sagging portions of the Leo Frigo Memorial Bridge on I-43 in Green Bay, Wisconsin is scheduled to begin Tuesday.  According to the Green Bay Press Gazette,  Zenith Tech Inc. is working on the repairs.  It will be a BIG lift, indeed…..

Raising the troubled Leo Frigo Memorial Bridge back into place will be a task equivalent to hoisting an entire fleet of 747s into the air.

Experts have calculated that the sagging section of Green Bay’s distressed bridge weighs more than 3 million pounds, or about 1,600 tons.

……

Zenith Tech crews are expected to spend several days using hydraulic jacks to boost the Leo Frigo back into position — a process that will go slow, by design.

……

Starting with the northbound lanes, Zenith Tech will insert 10 hydraulic jacks beneath the bridge deck and operate them all simultaneously to raise the platform. Each jack will be exerting enough pressure to support 183,000 pounds, although Dreher said their capacity is 50 percent greater than that — just in case it is needed.

Dreher said the jacks will be calibrated carefully to operate in perfect unison, so there is no risk of the bridge deck leaning one way or the other as it is elevated.

“You can’t just go in there and start jacking away,” he said. “It definitely takes some coordination and good communication.

A very challenging and interesting repair project.  Kudos to the Wisconsin DOT and all involved in getting the repairs done quickly.

See our previous posts here.

Charles J. Berkel 1925-2013

A pioneer of the deep foundations industry has recently passed.  Charles J. Berkel, 88, Chairman of the Board and Founder of Berkel & Company, one of the largest piling contractors in the U.S., passed away November 4, 2013.  From DFI:

Berkel graduated from the University of Illinois in 1946 with a B.S. in Civil Engineering. A year later he began his career in deep foundation construction working for Intrusion-Prepakt in Chicago. While there he was the project engineer for the first commercial project supported on ACIP piles in the U.S. In 1959 he resigned from Prepakt and started his own company, Berkel & Company Contractors, specializing in pressure grouting and the installation of Auger Pressure Grouted (APG) piles. Over the decades, he grew the company to become one of the largest piling contractors in the U.S.

Funeral services were held Friday, November 8, 2013, in Lenexa, Kan. In lieu of flowers, the family suggests donations in Berkel’ s name to the University of Saint Mary, Leavenworth, Kan., the Sister Servants of Mary, Kansas City, Kan., or Sacred Heart Church in Shawnee, Kan.

Mr. Berkel was a Charter Member of Deep Foundations Institute (DFI), Berkel was the recipient of the 2007 DFI Distinguished Service Award, and a major donor to the DFI Educational Trust Scholarship Program.

You can read more about Mr. Berkel here.

Leo Frigo Bridge–Repair Design

The Wisconsin DOT was set to request bids this week for repairs to the Leo Frigo Memorial Bridge on I-43 in Green Bay, with an anticipated start of construction on November 4th and reopening of the bridge on January 17th.  The repair will consist of using drilled shafts installed adjacent to the existing piers with a post-tensioned extension of the pile cap to transfer the loads to the shafts.  A schematic of the design from Wisconsin DOT (via Milwaukee Wisconsin Journal Sentinel)

Scot Becker, director of the Bureau of Structures and the state’s bridge engineer, said the fix will consist of installing four concrete shafts beneath five affected piers to take over support from corroded underground steel structures, called pilings. Then, the bridge itself will be jacked up 2 feet, and concrete and steel will be poured to keep the bridge in position.

The bridge, which spans the Fox River in Green Bay, has been closed since late September, after pilings became corroded and buckled under one of the piers, causing a 400-foot-long section of the bridge to sink 2 feet. Since then, it has drooped another half inch, and the state is monitoring the bridge for further movement.

An investigation concentrating mainly in the area from Quincy St. to the Fox River found that soil surrounding the pier contained industrial byproducts over wetlands, which caused the corrosion.

Temporary supports are already being installed by Lunda to shore up the sagging spans until the repairs can be completed.

The Green Bay Press Gazette has a page archiving all of their stories, videos, photos, etc. concerning this event.

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Leo Frigo Bridge–Corroded Piling

Image: From GreenBayPressGazette.com

Early indications are that the settlement of the pier at the Leo Frigo Bridge in Green Bay, Wisconsin is the result of corrosion of the piling that supports the pier.  Randy Post over at Geoprac.net  has a post up with video and a link to this story in the Green Bay Gazette Press.  From the story:

Corrosion of steel pilings below a support pier on the Leo Frigo Memorial Bridge in Green Bay caused Pier 22 to buckle last week, creating a long, deep dip in the bridge deck and forcing the bridge’s indefinite closure.

The 100-foot-long pilings under the pier were degraded from a combination of water and the composition of soil surrounding the bridge support, Wisconsin Department of Transportation officials said Thursday.

It appears that the suspect piers are in an area of fill, the composition of which may be contributing to the corrosion of the piles:

The investigation is focused on the area from the Fox River east to North Quincy Street on the east side of the bridge, where fill materials like foundry sand and organic materials are part of the soil profile.

“We’ve encountered all kinds of different things,” Buchholz said about soil samples in that area.

In addition to investigating the cause of the settlement of the pier, the bridge has been inspected by the Wisconsin DOT and is not in danger of collapse.  As a precaution, the bridge remains closed during the investigation.

Happy Karl Terzaghi’s Birthday 2013!

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Happy Karl Terzaghi’s Birthday, my friends!  Yes, it is time to raise our coffee, espresso, tea, wine, beer or other beverage to toast the Father of Modern Soil Mechanics as has been our custom here at the DBA blog.

As I pondered what to write this year, I perused a couple of books and ended up looking through my copy of Richard Goodman’s  “Karl Terzaghi – The Engineer as Artist”.  Among the many stories and accounts, I found this passage recounting an incident in the late 1950s (Ch. 17, pp245):

At this critical time, the world was reminded of the terrible consequences of dam failure when Board member Andre Coyne’s Malpassat Dam failed in France, causing more than 400 deaths (in Frejus, very near Ruth’s 1939 refuge on the French Riviera).  It failed on the initial filling of the reservoir due to geological weakness in one of the rock abutments of the very thin concrete arch.Later Karl would express sever criticism of the decision to bold such a structure on a geologically inadequate site.  But now he comforted his distraught colleague, writing that “failures of this kind are, unfortunately, essential and inevitable links in the chain of progress in the realm of engineering, because there are no other means for detecting the limits to the validity of our concepts and procedures…. The torments which you experienced should at least be tempered by the knowledge that the sympathies of your colleagues in the engineering profession will be coupled with their gratitude for the benefits which they have derived from your bold pioneering.”

Throughout the book, Goodman does an excellent job of showing the different facets of Terzaghi, and this is no exception.  He had a reputation of being a tough, direct, and straight-forward engineer that did not pull punches.  Here we see a somewhat softer side as he comforts a colleague, who was an expert in his own right.

If you have not read Goodman’s book, I highly recommend it for all Terzaghi fans!  It is published by ASCE and can be found through the ASCE Bookstore, or at other book retailers.  (Disclosure:  Neither DBA or any of its employees receive any commissions, compensation, or other considerations for promoting this book.)