Edmonton Technical Lunch - Thursday, January 25, 2018

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NASTT Colleagues and Friends

Please join us for the third technical lunch of the 2017-2018 season on Thursday, January 25th, 2018.

As part of their Urban Pipeline Replacement Program, ATCO Pipelines is working to replace and relocate its vintage high pressure natural gas pipelines in Calgary and Edmonton primarily into the Transportation Utility Corridors (TUCs) surrounding both cities. One of the projects as a part of this program, the Southwest Edmonton Connector (SWEC), includes the installation of 21 km of 508 mm diameter pipeline through southwest Edmonton. Due to the natural topography, unstable slopes and high level of existing infrastructure, Horizontal Directional Drilling (HDD) was utilized to complete 40% of the pipeline installations. The Whitemud Creek crosses the TUC near the eastern termination point of the project, and is at the bottom of a nearly 30 m deep ravine. Beginning in the early 1900’s, extensive mining was conducted which created hundreds of meters of room and pillar mine works which extend in all directions centralized at the Whitemud Creek. These workings were found in conflict with two of the HDD installations, the Whitemud Creek Crossing as well as a crossing of Anthony Henday Drive. An extensive borehole drilling program, as a well as seismic tomography survey, were used to map the mine works and to assess the level of potential collapse.

To facilitate the installation of the Whitemud Crossing, Thurber Engineering (Thurber) planned and executed an extensive geotechnical investigation. This included 24 boreholes up to 80 m deep and collecting seismic tomography data to determine the potential for voids and presence of existing mine works. Based on the information collected, a ground improvement plan was developed to grout a section of the mine that was determined to be non-collapsed. To maximize the ground improvement plan’s effectiveness, it was broken into two parts, a pilot grouting (proof of concept) section, and the full grouting section. A total of 105 grout holes were used for the ground improvement program.

Associated Engineering (AE) was retained to complete the design of the crossing by horizontal directional drilling methods. This included borepath design, hydrofracture, and pipe stress analysis. AE and Thurber carried out a parametric study using the finite element method (FEM) to optimize the pipe wall thickness within the limits of the ground improvement zone. As material stress aspects of the crossings were critical, aspects of the borepath design were refined further to maximize the opportunity for successful installations. This presentation provides an overview of the design and construction methodology utilized to successfully complete 700 m long crossing of the Whitemud Creek.

This month’s presenter is Jason Lueke. Mr. Lueke is the National Practice Leader for Trenchless Engineering at Associated Engineering. He has over 18 years of experience in consulting, construction, education, and research focusing specifically on trenchless engineering and construction. Jason served six years on the Board of Directors for the North American Society for Trenchless Technology (NASTT); and is an instructor for their Lateral Sewer Rehabilitation, Horizontal Directional Drilling, and Pipe Bursting Best Practices Courses. He has published over 60 journal and conference papers related to trenchless design, construction, and research; co-authored NASTT’s Laterals Good Practices Guidelines; served as the Chair of the Blue-Ribbon Review Committee on ASCE’s Pilot Tube and Other Guided Boring Methods MOP; and is on the Editorial Advisory Board of Trenchless Technology Canada Magazine.

Registration Closed

Place: University of Alberta Faculty Club, Papaschase Room, 11435 Saskatchewan Drive

Time:
11:30 am Registration
12:00 pm Lunch
12:30 pm Guest Speaker
1:30 pm Adjournment
Registration fees for the 2015-2016 program

Regards,
Greg Tippett, P.Eng.
NASTT-NW Chapter