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Oxford Northport Business Park Buildings A and B

Oxford Northport Business Park Buildings A and B
Date: 2014

The City of Edmonton has been experiencing an exponential growth in recent years. As part of the strategic urban development, the City’s northwest quadrant was chosen for commercial developments, housing warehouses, and distribution platforms. The Oxford Northport Business Park is one of the new developments seeking to accommodate existing companies looking to expand their business and to welcome emerging businesses wanting to use Edmonton as a base to supply their products to Northern Alberta. General contractor Dawson Wallace Consulting Group awarded Agra the piling subcontract for buildings A and B. The conditions on site were characterized by a succession of clay and sand layers overlaying clay till between 12 to 20 m deep. The sand layers were saturated with water and presented severe sloughing conditions.

Solution:

The original design consisted of cast-in-place belled piles with shaft/ bell diameters ranging from 406 mm/1219 mm to 762/ 2134 mm and a bottom-of-bell elevation of 12 m below the working grade. Due to the very heterogeneous soil conditions typical to this part of the city, the piles below Building B had to be extended to depths of up to 22 m below existing grade in order to reach adequate bearing ground for the bell. This situation, along with the presence of sand layers with sloughing conditions requiring the piles to be fully cased, resulted in a considerable increase in the final pile installation price and duration for Building B. Agra presented the client with a design build alternative solution for Building A: CFA piles proved to be more efficient in these soil conditions and generated increased productivity and considerable savings in the overall cost of the project.