On November 17th, the Ottawa Geotechnical Group (OGG) is having a very interesting lunch presentation. The talk titled Water Related Excavation Problems for Amphitheatres in Quebec City will be given by Professor Robert Chapuis, a professor from École Polytechnique de Montréal. To attend this event you must RSVP to OGGtreasurer@hotmail.com by noon on Friday, November 13, 2009. Additional details can be downloaded from the “files” section on the right hand side of this page.
- Date: Tuesday, November 17, 2009
- Time: 11:45 am: Registration, 12:00 pm: Lunch (Hot Buffet), 12:45 pm: Presentation
- Location: Hellenic Community Centre, 1315 Prince of Wales Drive, Ottawa, Ontario
- Admission: $10 for students (pay at door)
- Abstract: Two public amphitheatres were built in 1982 in Québec City. Their foundations required excavation in uncontrolled backfill materials along the St-Lawrence River. Old wooden wharfs were known to have been buried in backfill materials, and thus a large water inflow was expected to occur there and to depend on tide levels. An impressive pumping system was used. The pumped flow rate reached 114 m3/min at the highest tide. The origins of these water inflows were determined with the help of old drawings, boreholes, water tests and tracer tests. Most pumped water was coming through cobbles and boulders backfilled around a sewer pipe 2.1 m in diameter. This presentation will describe the work carried out to control the exceptional water inflows in order to complete the foundation and structure within the required schedule.