Tag Archives: Engineering Research

Deep Foundations Research

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In the course of digging throughout the internet for data and information for a couple of projects using one of the best wifi routers, I came across some (relatively) recent research reports geared toward improving design of driven piles based on field testing.  A report from The Illinois Center for Transportation at the University of Illinois at Urbana-Champaign is focused on improving pile design through increased resistance factors and nominal bearing values.  A project by the Institute for Transportation at Iowa State University focuses on developing LRFD design procedures for steel piles in Iowa. It was published in two volumes, with Volume I covering the development of LRFD calibrations and a load test database, and Volume II covering field load tests performed for the project.

I have not had time to dig into them yet, so I just offer the links and abstracts to pique your curiosity.  Perhaps you may find something interesting in them, or maybe something applicable to a project.  There is a lot of research going on out there for TRB and NHI, so I figure sharing interesting tidbits helps get things circulated.

Click on the name of each of the research centers above to find out what other things they are doing, available reports, etc.

 

Improved Design for Driven Piles on a Load Test Program in Illinois, Research Report FHWA-ICT-12-011, Illinois Center for Transportation, University of Illinois at Urbana-Champaign, July 2012 (Authors: Jim Long and Andrew Anderson, )

Abstract:

Dynamic pile testing and one static load test was performed in accordance with ICT project R27-69, “Improved Design for Driven Piles Based on a Pile Load Test Program in Illinois.” The objectives of this project are to (1) increase the maximum nominal required bearing that designers can specify to reduce the number and/or weight of piles, (2) decrease the difference between estimated and driven pile lengths to reduce cutoffs and splice lengths by development of local bias factors for predictive methods used in design, (3) increase reliance of pile setup to increase the factored resistance available to designers, (4) reduce the risk of pile driving damage during construction, and (5) increase the resistance factor (decrease in factor of safety) based on increased data and confidence from load tests in and near Illinois. Project deliverables can be categorized as (1) better prediction methods for stresses during driving, (2) better prediction methods for pile capacities using resistance factors for driven piling based on local calibrations that consider the effects of pile setups, and (3) collections of static and dynamic load test data focused on Illinois soils and geology.

 

 

Development of LRFD Procedures for Bridge Piles in Iowa, Volume I: An Electronic Database for PIle LOad Tests (PILOT) (Volume I), Institute for Transportation at Iowa State University, January 2011 (Authors: Matthew Roling, Sri Sritharan, Muhannad T. Suleiman)

Abstract:

For well over 100 years, the Working Stress Design (WSD) approach has been the traditional basis for geotechnical design with regard to settlements or failure conditions. However, considerable effort has been put forth over the past couple of decades in relation to the adoption of the Load and Resistance Factor Design (LRFD) approach into geotechnical design. With the goal of producing engineered designs with consistent levels of reliability, the Federal Highway Administration (FHWA) issued a policy memorandum on June 28, 2000, requiring all new bridges initiated after October 1, 2007, to be designed according to the LRFD approach. Likewise, regionally calibrated LRFD resistance factors were permitted by the American Association of State Highway and Transportation Officials (AASHTO) to improve the economy of bridge foundation elements. Thus, projects TR-573, TR-583 and TR-584 were undertaken by a research team at Iowa State University’s Bridge Engineering Center with the goal of developing resistance factors for pile design using available pile static load test data. To accomplish this goal, the available data were first analyzed for reliability and then placed in a newly designed relational database management system termed PIle LOad Tests (PILOT), to which this first volume of the final report for project TR-573 is dedicated. PILOT is an amalgamated, electronic source of information consisting of both static and dynamic data for pile load tests conducted in the State of Iowa. The database, which includes historical data on pile load tests dating back to 1966, is intended for use in the establishment of LRFD resistance factors for design and construction control of driven pile foundations in Iowa. Although a considerable amount of geotechnical and pile load test data is available in literature as well as in various State Department of Transportation files, PILOT is one of the first regional databases to be exclusively used in the development of LRFD resistance factors for the design and construction control of driven pile foundations. Currently providing an electronically organized assimilation of geotechnical and pile load test data for 274 piles of various types (e.g., steel H-shaped, timber, pipe, Monotube, and concrete), PILOT (http://srg.cce.iastate.edu/lrfd/) is on par with such familiar national databases used in the calibration of LRFD resistance factors for pile foundations as the FHWA’s Deep Foundation Load Test Database. By narrowing geographical boundaries while maintaining a high number of pile load tests, PILOT exemplifies a model for effective regional LRFD calibration procedures.

 

 

Development of LRFD Procedures for Bridge Piles in Iowa, Field Testing of Steel H-Piles in Clay, Sand, and Mixed Soils and Data Analysis (Volume II), Institute for Transportation at Iowa State University, September 2011 (Authors: Kam Weng Ng, Muhannad T. Suleiman, Matthew Roling, Sherif S. AbdelSalam, and Sri Sritharan)

Abstract:

In response to the mandate on Load and Resistance Factor Design (LRFD) implementations by the Federal Highway Administration (FHWA) on all new bridge projects initiated after October 1, 2007, the Iowa Highway Research Board (IHRB) sponsored these research projects to develop regional LRFD recommendations. The LRFD development was performed using the Iowa Department of Transportation (DOT) Pile Load Test database (PILOT). To increase the data points for LRFD development, develop LRFD recommendations for dynamic methods, and validate the results of LRFD calibration, 10 full-scale field tests on the most commonly used steel H-piles (e.g., HP 10 x 42) were conducted throughout Iowa. Detailed in situ soil investigations were carried out, push-in pressure cells were installed, and laboratory soil tests were performed. Pile responses during driving, at the end of driving (EOD), and at re-strikes were monitored using the Pile Driving Analyzer (PDA), following with the CAse Pile Wave Analysis Program (CAPWAP) analysis. The hammer blow counts were recorded for Wave Equation Analysis Program (WEAP) and dynamic formulas. Static load tests (SLTs) were performed and the pile capacities were determined based on the Davisson’s criteria. The extensive experimental research studies generated important data for analytical and computational investigations. The SLT measured loaddisplacements were compared with the simulated results obtained using a model of the TZPILE program and using the modified borehole shear test method. Two analytical pile setup quantification methods, in terms of soil properties, were developed and validated. A new calibration procedure was developed to incorporate pile setup into LRFD

Characterization of Loess for Deep Foundations

loess map

 

I have added a recent paper that Dan and Steve contributed to concerning loess that is in the November, 2009 issue of the DFI Journal.  The paper describes the results of site investigation and laboratory tests at a site in Kansas with loess deposits.  The effectiveness of various correlations between field and laboratory tests and design properties are evaluated.  Steve is currently working on the follow-up paper that evaluates lateral load tests of drilled shafts at the site.

Parson, R.L., Johnson, R.M., Brown, D.A., Dapp, S.D., and Brennan, J.J., 2009. “Characterization of Loess for Deep Foundations”, DFI Journal Volume 3, No. 2, November 2009, Deep Foundations Institute, pp14-24.

Another Legend Passes – Dr. Lymon C. Reese

I wanted to make a quick post on the passing of Dr. Lymon Reese – Dan’s mentor, Ph.D. advisor, and a great engineer.  I’ll post more later as it becomes available. (and catch up posts on our normal activities that I am way behind on).  Below is from an e-mail sent by the ADSC.

 

Drilled Shaft Foundation Industry Giant

Dr. Lymon C. Reese Passes

       Drilled Shaft Foundation Industry Giant  Dr. Lymon C. Reese Passes

We are sad to report that Dr. Lymon C. Reese, Professor Emeritus, University of Texas, Austin, and one of the world’s leading drilled foundation experts, passed away on Monday, September 13, 2009. Dr. Reese was an ADSC Honorary Technical Affiliate Member and a great friend to the ADSC and to the drilled foundation industry. His seminal drilled shaft foundation research conducted for the Texas Department of Transportation and his subsequent writings are among the most important work ever conducted in the field. His graduate students have achieved international acclaim in their own right, and include: Dr. Michael W. O’Neill (deceased), Dr. Dan A. Brown, Larry Olson, Dr. Magued Iskander, Dr. James Long, and many others, all of whom have had a major impact on the advancement of the drilled shaft foundation industry. Dr. Reese was one of the last surviving early “giants” of our industry. At age 92, he remained a vibrant contributor to the profession. To say he will be sorely missed is an understatement. We have lost a most beloved friend.

Further details regarding a Memorial Service will be posted on the ADSC website as they become available.

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Foundation Drilling article (May 2009): Drilled Shaft Loadtests in Limestone by Dan and Robert

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The May 2009 issue of Foundation Drilling had an article by Dan and Robert summarizing the recent research on drilled shafts socketed into rock for the Southeast Chapter of ADSC .

The article has been posted to our Publications Page.  The full report is located here, for those looking for a little light reading. 

A test site has been selected for Atlanta in the Piedmont formation.  Check back here or at the project page for updates as things move forward.

 

Nashville site shaft excavation

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