NEWS 2010

Posted February 15, 2010 (Updated March 20, 2010)

Event: March 25, 2010

GSE: 2010 Annual Symposium - AM: Ground Improvement by Hayward Baker & PM: Local Geotechnical Engineers, Reprise of 2009 CGS Papers

Location: Edmonton Petroleum Club (11110 - 108 Street, Edmonton)

Time: 8:30am - 4:00pm

$100 Members, $110 Non-members, $20 Students (Early Bird deadline has passed)

Morning Session: Ground Improvement Techniques

Tim Avery of Hayward Baker will present an overview of selected ground improvement methods, including deep dynamic compaction, vibro compaction/replacement, deep soil mixing (wet and dry), compaction grouting and jet grouting. Over the past 35 years, ground modification techniques have played an increasingly important role in geotechnical engineering. Ground modification is the in-situ treatment of soils to achieve such project objectives as increased bearing capacity, settlement control, soil stabilization, groundwater control, and liquefaction mitigation.

Tim Avery holds a B.S. & M.S. in Geological Engineering from the University of Arizona and has over 25 years experience in engineering and construction. Mr. Avery manages and coordinates the marketing and sales of Hayward Baker’s specialty geotechnical construction methods for the Western Region. Hayward Baker is a ground modification contractor specializing in grouting, liquefaction mitigation, ground modification and earth retention. They are part of the international contractor, Keller, which is based in London.

Presentation PDF's and other material provided by Mr. Avery:

• Introduction and Deep Dynamic Compaction (PDF 5 Mb)
• Deep Soil Mixing (PDF 11 Mb)
• Vibro Methods (PDF 5 Mb)
• Additional Material: FHWA papers, brochures, case studies, sample specifications (LARGE zip file, 180 Mb)

Afternoon Session: Encore Presentations of selected papers from the 2009 CGS Conference in Halifax

Analysis of field performance of landslide repair using a pile wall

C.K. Grapel, A. Azizian, A.F. Ruban, R. Skirrow and E. Szmata

Paper was not presented at Symposium

A historically slow moving embankment fill landslide on Secondary Highway 682:02 accelerated to failure in the spring of 2007. The landslide was translational with the failure plane located between 4.5 and 6.5 m depth within native lacustrine clay. The stabilization repair method selected was a pile wall that consisted of 67 cast-in-place reinforced concrete piles spaced at 1.5 m on centre. Field performance of the pile wall after completion of construction was verified using two slope inclinometers that were embedded in two of the concrete piles. Post-construction deformations were within the range suggested during the design. Analysis of the construction deformation using FLAC provided insight into the selection of material properties, especially soil stiffness moduli, for the future design of pile walls used for landslide stabilization.

Static axial load test on strain gauge instrumented concrete piles

Baocheng Li and Tony Ruban

CGS Paper (PDF 1 Mb)

The Edmonton New Remand Center (ENRC) will be a multi-building complex located in Edmonton, Alberta. The foundation system for the ENRC comprised more than 2,600 continuous flight auger (CFA) piles. The subsurface conditions at the project site consisted of lacustrine deposits of clay and silt underlain by highly variable strata of glacial clay till and clay shale bedrock. A pile load testing program was undertaken to optimize the design of the piles by determining the shaft resistance being developed along the length of the test piles within the different subsoil strata. The load testing program consisted of a total of four axial compressive load tests on strain gauge instrumented CFA concrete test piles. The pile load tests permitted a significant increase in the design shaft friction parameters, which provided substantial cost savings for the project foundations.

Lateral resistance of helical monopole bases

Mohammed Sakr

CGS Paper (PDF 13 Mb)

A Helical Monopole Base (HMB) is a two-section steel pipe shaft with a helix or more near the bottom of each shaft section. HMBs are used regularly in Alberta as foundation pockets for single and double circuit distribution power line poles. The results of a comprehensive lateral pile load test program and field monitoring of HMBs installed in organic soil (muskeg) over soft clay are presented in this paper. A total of eight full scale lateral load tests were carried out including six tests using HMBs with different diameters and embedment depths and two tests using single shaft helical piles. The prime objective of the study was to evaluate the lateral performance of helical monopole bases and to compare the lateral resistance of HMBs to straight shaft helical piles. This paper summarizes the helical pile installation, test setup and discusses the test results. The results of the load tests are compared to a theoretical model using LPILE Plus 5, a program widely used to estimate the lateral pile resistance based on the p-y curves.

Mechanisms and kinematics of three translational slides along the North Saskatchewan River Valley, Edmonton

K.W. Soe Moe, Dave Cruden, Derek Martin, Don Lewycky and Paul Lach

CGS Paper (PDF 2 Mb)

A study of three translational landslides along the North Saskatchewan River Valley in Edmonton is presented in this paper. The major focus is on kinematics and mechanisms of the river valley landslides in weak rocks. The study found that the river valley landslides are caused by a combination of several factors, including toe erosion by the river, residential developments behind the slope crests, the rise of groundwater levels due to urban development, and softening of the bedrock at the valley wall. Case studies revealed that river valley landslides in weak rocks developed in stages starting as a minor toe failure and gradually retrogressing upslope at a later stage causing major failure.

Comparison of shear-wave velocity measurements by crosshole, downhole and seismic cone penetration test methods

Nagula Suthaker and Robin Tweedie

CGS Paper (PDF 11 Mb)

A field testing program was undertaken at a proposed petrochemical plant site near Edmonton, Alberta to measure shear wave velocities. The proposed site in underlain by lacustrine clay, glacial till and upper Cretaceous clay shale and sandstone bedrock in descending order. The shear wave velocities were measured by Crosshole and Downhole Seismic tests as well as Seismic Cone Penetration Tests (SCPT). This paper describes the test results and comparison of three shear wave velocity measurement techniques and discusses the limitation of the various methods.

Comparison of static and high strain dynamic tests on driven steel piles at several industrial sites in Alberta

Robin Tweedie, Renato Clementino and Don Law

CGS Paper (PDF 1 Mb)

This paper describe three case histories where static load tests (SLT) and high strain dynamic tests (HSDT) were conducted on driven steel piles at industrial plant sites in Northern Alberta. The sites involved H-section and pipe piles up to 610 mm diameter driven to depths ranging from 10 m to 40 m, with design loads up to 2200 kN. A combination of SLT and HSDT provided information on capacity, distribution of shaft and end bearing resistance, and “set-up”. HSDT were an economical method of providing quality assurance and confirmation of pile capacities during construction.