(Post and photos provided by John Turner, Ph.D., P.E., D.GE of DBA.)
DBA has had the privilege to be the geotechnical/foundation engineer for the Goethals Bridge Replacement (GBR)Project, a design-build project for the Port Authority of New York & New Jersey (PANYNJ). The project will replace the existing Goethals Bridge that was built in the 1920s and carries I-278 over the Arthur Kill River between Elizabeth, New Jersey and Staten Island, New York.
Construction of drilled shafts continues as the superstructure begins to emerge over the skyline between Elizabeth, NJ and Staten Island, NY. The new bridge will be a dual-span 1,983-ft long cable-stayed bridge with approach spans of over 2,500 ft on each side. The bridge is supported on over 200 drilled shaft foundations ranging in diameter from 4.5 ft to 10 ft and socketed into Passaic Formation siltstone.
The GBR is a Public-Private Partnership (P3) that represents a major milestone for the PANYNJ in its distinguished history of bridge building in the greater New York City metropolitan area. The existing Goethals Bridge along with the Outerbridge Crossing and the Bayonne Bridge comprise the three Port Authority bridges connecting Staten Island with New Jersey. The Goethals Bridge and the Outerbridge Crossing are cantilever truss structures and both opened on the same day in 1928. They were designed by J.A.L. Waddell under the supervision of the eminent engineer Othmar H. Ammann (1879-1965), who was the designer of many other iconic bridges in the NY City area including the Bayonne Bridge (1931), the George Washington Bridge (1931), and the Verrazano Narrows Bridge (1964). The designer of record for the replacement Goethals Bridge is Parsons Corporation, which is the successor firm of Robinson & Steinman, whose principal David B. Steinman was also a notable NY area bridge designer and a contemporary and rival of O.H. Ammann.
Each main pylon tower of the GBR is supported on a group of six 9-ft diameter drilled shafts and each anchor pier is supported by two 10-ft diameter shafts. Approach piers are two-column bents with each column supported on a rock-socketed drilled shaft.
DBA is the foundation design engineer of record and this project provides an example of how rock-socketed drilled shafts can provide a reliable and cost-effective means of supporting a major bridge by taking advantage of the high resistances that can be achieved. Key factors involved in taking advantage of rock sockets for this project were: (1) load testing to demonstrate high axial resistances (>30 ksf side resistance and >300 ksf base resistance), (2) utilization of all relevant construction QC/QA tools to ensure that rock sockets are constructed in a manner that is consistent with construction of the load-tested shafts that provide the basis of the design, (3) close collaboration between all members of the design-build team, and (4) adequate subsurface characterization, especially a thorough characterization of rock characteristics and their effect on socket resistances. Load testing for this project demonstrates that side and base resistances can be used in combination to design rock socketed shafts for axial loading. This approach avoids the use of unnecessarily deep sockets, thereby minimizing the associated construction risks and costs.
The GBR project developer is NYNJ Link Developer, LLC and construction is being performed by a joint venture of Kiewit-Weeks-Massman (KWM). Parsons is the lead designer. A construction web-cam and additional information on the GBR can be found at the Port Authority’s website: http://www.panynj.gov/bridges-tunnels/goethals-bridge-replacement.html
The Transportation Research Board (TRB) has released a synthesis report prepared by Dan and Robert on large diameter piles: NCHRP Synthesis 478, Design and Load Testing of Large Diameter Open-Ended Driven Piles. The report is a summary of the state of practice with regard to Large Diameter Open-Ended Piles (LDOEPs) in the transportation industry. We conducted a survey of state DOTs as well as interviews with private practitioners to summarize current practices as well as recommend best practices with regard to the selection, design, installation, and testing of LDOEPs. Several state DOTs are using LDOEPs more regularly where large foundation loads may exist and/or the piles are subject to significant unsupported length due to scour, liquefaction, or very weak surficial soils. Marine construction conditions also favor the use of these piles, particularly where pile bents might be employed to eliminate footings.
You can download a PDF of the report or purchase a hard copy at the link below.
DBA is on the design-build team that is replacing the Goethals Bridge for the Port Authority of New York and New Jersey (PANYNJ). We are not able to post much about the project or our involvement due to security agreements. However, the PANYNJ has a public website for the project (http://www.panynj.gov/bridges-tunnels/goethals-bridge-replacement.html) that has several webcams. As is the case with most big projects these days, the webcams are a common feature and show some great views of the project.
To give you an idea of what the project involves, here is a summary from the PANYNJ site:
The replacement bridge will be located directly south of the existing bridge and will provide:
- Three 12-foot-wide lanes in each direction replacing the current two narrow 10-foot-wide lanes
- A 12-foot-wide outer shoulder and a 5-foot-wide inner shoulder in each direction
- A 10-foot-wide sidewalk/bikeway along the northern edge of the New Jersey-bound roadway
- Improved safety conditions and performance reliability by meeting current geometric design, structural integrity, security and seismic standards, and reduces life-cycle cost
- A central corridor between the eastbound and westbound roadway decks, sufficient to accommodate potential transit service
- State-of-the-art smart bridge technology
The project also includes the demolition of the existing bridge upon completion of the replacement bridge.
You can learn more about the project at the same web site. There is also a site for the current bridge, including history of the construction, etc.
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.
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.)
Although 2015 seems like a long way away, when you are planning the largest foundation engineering and construction conference in the U.S., you need to get started early! The organizing committee for the the 2015 International Foundations Congress and Equipment Exposition (IFCEE 2015) has released the Call for Abstracts here at the conference website.
This conference will be at the JW Marriott in San Antonio, Texas, March 17-21, 2015 and is hosted by a joint effort of ADSC: The International Association of Foundation Drilling (ADSC), Deep Foundations Institute (DFI), Geo-Institute of the ASCE (G-I), and Pile Driving Contractors Association (PDCA). The program will include technical paper sessions (as poster or podium presentations), panel discussions and debates, indoor exhibits, an outdoor equipment exposition, educational short courses, technical committee meetings, and networking events.
Early this year, NCHRP released a synthesis report on geotechnical practices related to design-build projects. I have had writing a blog post on this on my “to do” list for a few months and finally got down the list!
NCHRP Synthesis 429 – Geotechnical Information Practices in Design-Build Projects is a report on the current practices of allocating and managing geotechnical risk through the use (or lack of!) geotechnical information in transportation project bid documents. Even though design-build as a delivery process for projects has been around for a while now, the allocation of risk due to subsurface conditions is an issue still treated with a variety of approaches.
Those of us who have been in this industry for a while know that a thorough geotechnical investigation reduces both cost risk and construction/schedule risk. Design-build is an effective method for accelerating project construction and delivery; however, the acceleration of the schedule puts more pressure on the geotechnical design since “geotechnical investigation and design is usually the first design package that must be completed and geotechnical uncertainty is usually high at the time of DB contract award.”
Because geotechnical investigation and design is usually the first design package that must be completed and geotechnical uncertainty is usually high at the time of DB contract award, the design-builder’s geotechnical designers are under pressure to complete their work and enable foundation and other subsurface construction to commence. Successfully managing the geotechnical risk in a DB project is imperative to achieving the requisite level of quality in the finished product. The purpose of this synthesis is to benchmark the state of the practice regarding the use of geotechnical information in DB solicitation documents and contracts. The high level federal encouragement through EDC for state DOTs to accelerate project delivery by using DB elevates the need to manage geotechnical risk while expediting geotechnical design to a critical project success factor, and makes the results of this synthesis both timely and valuable.
As is the case with NCHRP synthesis reports, the authors conducted a literature review, conducted a survey of state DOTs and other agencies, and developed some conclusions that include effective practices for managing geotechnical risk.
The synthesis was based on a comprehensive literature review; a survey of U.S. DOTs, which received responses from 42 states (response rate = 84%); a content analysis of DB solicitation documents from 26 states; a content analysis of DB policy documents/guidelines from 12 state DOTs and 5 federal agencies; and interviews of 11 DB contractors whose markets encompass more than 30 states. The synthesis also furnishes three legal case studies (Colorado, Illinois, and Virginia) on cogent geotechnical issues and four geotechnical engineering case studies (Hawaii, Minnesota, Missouri, and Montana) that illustrate the methods transportation agencies use to deal with geotechnical issues on DB projects. Conclusions were drawn from the intersection of independent sources of information from the survey, case studies, and literature.
Some of the effective practices highlighted include the use of confidential Alternative Technical Concepts (ATC) during pre-bid, explicit differing site conditions (DSC) clauses that clearly quantify the design-build team’s risk and the threshold above which the DOT assumes the risk, the use of qualified personnel, and timely review schedules for geotechnical design items early in the project.
Our (DBA) experience in design-build has seen the range from effective practices to poor practices. This report provides a great summary of many of the effective practices we have found to be beneficial and that help reduce conflicts and delays. We can’t completely eliminate geotechnical risk, but it can be effectively and equitably managed.
Click on the link below to get a copy from NCHRP.
Earlier this week, officials from the Minnesota and Wisconsin departments of transportation (MnDOT and WisDOT) met for an official groundbreaking ceremony on the projected $629 million bridge and highway project that will connect Oak Park Heights, Minnesota, to St. Joseph, Wisconsin, just south of Stillwater, Minnesota, as highlighted in yesterday’s edition of The Minneapolis St. Paul Business Journal. The new bridge will replace the 80-year-old Stillwater Lift Bridge and relieve traffic congestion in nearby Stillwater.
DBA has been retained by MnDOT as the lead geotechnical consultant and foundation designer for the extradosed river bridge. Last summer, DBA aided MnDOT in the design and oversight of a load test program described in my blog post, “DBA Wraps Up Load Test Program and Proceeds with Design on St. Croix Bridge.” Following final design, which took place over the fall and winter, construction of the foundations will begin next week with the installation of a technique shaft. DBA will participate in construction as well, providing construction observation and review of the technique shaft and at least one shaft at each of the five production piers. Edward Kraemer & Sons, Inc. of Plain, Wisconsin, has been selected as the general contractor for the foundation contract with sub-contractor Case Foundation Company of Chicago, Illinois, performing the drilling. The extradosed bridge will feature five main river towers, each resting on two footings supported by a 4-shaft group of 8.5-foot drilled shafts, socketed 25-feet or more into sandstone bedrock.
I hope to have some more updates soon with some pictures following my upcoming site visits to observe the construction operations. In the mean time, you can stay updated by visiting the MnDOT project page and watching the “action” live via the construction webcam.
The months of September and October will be busy for several DBA team members speaking at a variety of conferences and events. Dan Brown and John Turner will be speaking at the ADSC/DFI Drilled Shaft Seminar and Field Day in Denver September 12 and 13. Dan will be giving the 4th Annual Osterberg Memorial Lecture at the DFI Educational Trust dinner being held on the evening of the 12th. Dan and John will be speaking mostly on construction issues during the seminar.
Later in the month, Dan and Robert Thompson are both featured at the 2012 Midwest Geotechnical Conference hosted by Ohio DOT in Columbus, Ohio. Dan will be speaking on base grouted shafts while Robert will give his presentation on the ADSC SE Chapter rock socket load test research program.
In October, Dan and Robert appear together again at the 2012 Southeastern Transportation Geotechnical Engineering Conference (STGEC) in Richmond, Virginia. This will be the 43rd installment of this conference, hosted this year by the Virginia DOT. Dan will speak on design-build construction issues for deep foundations, while Robert will again present the load test research project. Dan will also speak at the 26th Central Pennsylvania Geotechnical Conference in Hershey, Pennsylvania in October, and Robert will speak at the ADSC Carolinas Chapter meeting in Greenville, NC.