NSRB at Duvernay (BF71116) Strengthening for BLE

GeoMetrix was retained by Mammoet Canada to perform a Bridge Load Feasibility Study for a Splitter Permit Load Transported on Bunked 4- File 26 Line Conventional Scheuerle Configuration Crossing Nine Bridges on the Transport Route between Edmonton, AB and Redwater, AB. From this load evaluation it was found that the North Saskatchewan River Bridge (NSRB) on Highway 29, at Duvernay (BF71116) required strengthening for the load. The bridge consist of 76.5 – 77.0 – 77.0 – 76.5, continuous spans and a 12.2 m simple span (North end). The girders are supported on mass concrete piers and conventional abutments. GeoMetrix designed a post tension system using Dywidag bars to provide enough post tensioning moment effect to counteract the additional live load from the permit load. In conjunction with the strengthening, the analysis of the North Saskatchewan River Bridge (BF71116) assumed that the permit load may have an accident eccentricity of up to 0.60 m as per typical conditions for PC type loading. GeoMetrix considered limiting this eccentricity to 0.30 m during crossing via use of cones on the bridge. Using this approach, the moment distribution factor was reduced from 0.32 to 0.298.