Bridge eases Calgary growing pains
Residents of Calgary will be well
aware that the city’s growth has been accompanied by the seemingly
inevitable growing pains of traffic congestion.
Residents of Calgary will be well aware that the city’s growth has been accompanied by the seemingly inevitable growing pains of traffic congestion. This report describes one of several current roadbuilding projects to ease congestion.
The intersection of Beddington Tr. and Country Hills Blvd. is located in northwest Calgary and has seen rapid increases in traffic volumes with the growth of new residential communities on the north and west side of Calgary. Commuter traffic on both of these four lane roads has translated into significant delays, particularly during the morning and afternoon rush hour periods. Andrew Buchner, project coordinator for the Graham Construction and Engineering joint venture, explains that the project has three main elements to alleviate congestion. The project’s principal bridge structure will carry Beddington Tr. over Country Hills Blvd., while an existing bridge east of the intersection is being widened to accommodate an exit ramp for westbound Country Hills Blvd. traffic joining Beddington Tr. northbound or southbound. The third structure, a separate pedestrian bridge just west of the inter-section at Sanderling Dr. brings the values of the structures on the project to $13.7 million. Roadworks add $11.3 million, with utilities and street lighting adding another $2 million and $630,000 respectively for a total tender price of $32.3 million including contingency allowance and taxes. The contract was awarded in October 2007 and work began on site in December of that year. The two-year project is scheduled for completion in fall 2009.
This interchange improvement is Phase 6 of the SBC (Shaganappi Tr./Beddington Tr./Country Hills Blvd.) widening project being undertaken in response to growth in the northwest portion of the city. It includes four sections of roadway improvements including the interchange at Beddington Tr. and Country Hills Blvd. Phase 1 of the project, Beddington Tr. Widening from Deerfoot Tr. to Country Hills Blvd., includes widening Beddington Tr. from four lanes to six with intersection improvements at Beddington Tr. and Beddington Blvd. as well as Beddington Tr. and Berkshire Blvd./Country Hills Close. Phases 2 and 3 involve widening Shaganappi Tr. between Edgemont Blvd. to Hidden Valley Dr. from three lanes to five, three lanes southbound and two lanes northbound, and the widening of Country Hills Blvd. from four lanes to six from 14 Street N.W. to Hamptons Dr./Edgebrook Blvd. Phase 4 sees the widening of Country Hills Blvd. from four lanes to six between Beddington Tr. and Shaganappi Tr. with intersection improvements at Country Hills Blvd. and14 St. N.W. A 5th and final phase is currently being reviewed and would see the widening of Beddington Tr. from Country Hills Blvd. to Stoney Tr. N.W. from four lanes to six if given final approval. Currently there are no plans to construct Phase 5.
Construction is currently progressing on Phases 1, 2, 3 and 6 with the completion of Phases 1, 2 and 3 slated for later this year while Phase 6 will be fully opened to traffic in the fall of 2009. Phase 4 will be tendered some time later this year or early next for a 2009 construction season with an anticipated completion for the fall of that same year. Aside from the SBC Project, the city is also undertaking a small but crucial piece of widening on Deerfoot Tr. between Beddington Tr. and McKnight Boulevard N.W. that will see the addition of one right lane in the southbound direction to help alleviate some of the congestion on Deerfoot Tr. created by commuters trying to make their way into the downtown area. The city is undertaking this project on behalf of Alberta Transportation as it has a direct affect on the widening work associated with Phase 1.
At the time of Aggregates & Roadbuilding’s visit to the inter-change, earthworks subcontractor KLS was focussing on the placement and compaction of fill behind the main bridge abutments in preparation for placement of the twenty eight concrete girders. Some 120 000 m3 of imported soil fill was being compacted to a specified 100 per cent density for the top two metres and a minimum of 95 per cent beneath. During the same visit, formwork was being struck from the just completed single concrete pour of the bridge’s central pier. As a footnote, Buchner adds that the pier was completed in a single pour, with the somewhat unusual arched pier design incorporating post tensioning through the base and additional post tensioning in both shafts and the diaphragm.