A One-Day Workshop and Seminar by Bengt H. Fellenius, Dr. Tech., P.Eng.
Basics of Design of Piled Foundations
Monday, March 4, 2019
Coast Coal Harbour Hotel, 1180 West Hastings Street, Vancouver
This one-day event addresses the practice of piled foundation design. What data one must pull together and what processes of analysis and calculations necessary for a design of a specific project are presented. Negative skin friction and associated drag force and downdrag are emphasized along with settlement analysis. Various methods and aspects of determining pile capacity are presented and discussed. It is shown that the design emphasis should be on how to determine expected settlement and how to base a design on settlement. Indeed, the seminar makes it clear that deep foundation design involves a good deal more than finding some value of capacity.
The presentation includes both broad generalities and in-depth details. Specifics of where to install instrumentation, perform a test, and analyze the test data are addressed. Settlement analysis is of vital importance to the design of piled foundations, and the course addresses principles and mechanics of settlement analysis. How to consider and compare straight-shaft piles to piles with changing cross section, e.g., expanded base piles, open- vs. closed-toe pipe piles, is also addressed. Brief comments are given on some Code and Standards requirements for Limit States Design, LSD, (Ultimate Limit States, ULS, and Serviceability Limit States, SLS, by Canadian terminology, and Load and Resistance Factor Design, LRFD, by US terminology). The lectures are illustrated with case history examples throughout. Much emphasis is placed on the design and performance of pile groups and piled raft foundations.
Registration forms are provided here.
The registration deadline is February 22. The cancellation deadline is February 25, substitutions can be made after this date.
The registration fee is $325 for VGS/CGS members, $375 for non-members, and $200 for students.
All cheques and completed registration forms to be mailed to:
J.Y. (Yoshi) Tanaka
#65-1833 Coast Meridian Road
Port Coquitlam, BC
The course outline is provided here and summarized below:
8:30am Analysis of Load Transfer, Capacity, and Response to Load
Load-movement response of foundations; Bearing capacity and load-transfer; Set-up and relaxation; Design for scour condition; Residual force; Results of prediction events.
10:30am The Static Loading Test: Performance, Analysis, and Instrumentation
Methods of testing and basic interpretation of the results. How to analyze results from strain-gauge instrumented piles to arrive at resistance distribution along the pile shaft and the pile toe response. Determining pile elastic modulus. The importance of residual force and how to include its effect in the analysis. Principles and evaluation of the bidirectional test and case examples. Common mistakes in scheduling and performing static loading tests on instrumented piles. Case histories on results and analyses of static loading tests on driven and bored piles.
1:00pm Piles and Pile Groups — Long-Term Behavior and How We Know What We Know
Important case histories presenting studies that demonstrated the actual long-term response of piles to load and observed settlement of single piles, pile groups, and piled rafts. The lessons learned will be referenced to aspects of design applying the Unified Method for Design of Piled Foundations considering Capacity, Drag Force, Settlement, and Downdrag, including influence from adjacent structures, fills, and excavations. The presentation specifically addresses the response to load of piled rafts, pile enhanced foundations, and piled pad foundations ("inclusion" design).
3:15pm The Unified Design Method
Capacity (choice of factor of safety, and rules of LRFD and Limit States Design) and design for structural strength (including drag force).
Settlement of single piles and pile groups due to load directly on the piles and due to influence from adjacent activity (downdrag) as pertaining to single piles and pile groups (narrow as well as wide groups).
How to combine the various aspects for the design of an actual case with emphasis on foundation settlement illustrated with examples.
5:00pm Questions and Discussions
Dr. Bengt H. Fellenius is a professional engineer specializing in foundation design and studies by participation in project teams, special investigations, instrumented field tests, etc. Dr. Fellenius, Professor of Civil Engineering at the University of Ottawa from 1979 through 1998, is an internationally recognized authority in the field of soil mechanics and foundation engineering, and, in particular, in deep foundations. He has gained a wealth of practical experience during more than 50 years of work at home and overseas through a variety of assignments that encompass foundation, embankment, and soil improvement design for water and sewage treatment plants, industrial plants, as well as bridges, highway, and airport projects, and marine structures and urban area development projects; some of which he has written up in 350+ technical journal and conference papers, articles, books, and book chapters.
Dr. Fellenius moved from his native Sweden to Canada in 1972 from where he worked on foundation investigations and design and construction projects in North America and overseas. In 1973, he was one of the first to apply geotextile soil separation sheets to stabilize roadbeds and construction surfaces, investigating conventional carpet underlay (Celanese) for this purpose. He was active in promoting to the US market the splicing of prestressed concrete piles by means of mechanical full-strength splices, and he introduced to Canada and the USA ground improvement applications of lime column method for reducing soil compressibility and wick drains (the Geodrain and Alidrain) for accelerating consolidation and stabilizing landslides. He was one of the earliest (1977) practicing engineers to research and use dynamic testing and the Pile Driving Analyzer in actual project design and construction.
In 1984 he introduced the Janbu method of determining soil compressibility and analysis of settlement to North-America. He has also had a fundamental part of the development of commercial software for analysis of settlement from loads on natural soils and soils subjected to soil improvement methods, design of piled foundations, and other software. In 1984, he published the design and analysis method for foundation design known as the “Unified Method of Design for Capacity, Drag Force, Settlement, and Downdrag”.
Dr. Fellenius is and has been an active participant in many national and international professional societies and research associations and in Canadian and US Codes and Standards Development.