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| Project Name: | Bridge Replacement on a Local Road over SMRID Canal |
| Location: | 1 km south of Lethbridge, AB |
Previous Structure: 2 span, 2 x 8.5 m type HC girder bridge on a treated timber substructure.
New Structure: 2 span, 2 x 12 m type SL-510 precast girder bridge on a steel substructure.
The existing bridge was nearing the end of its service life with abutment stability issues and serious checks and splits throughout the substructure. The replacement structure will provide 75 years of service life with excellent flow characteristics for the irrigation canal.
There were many viable replacement options at this site, including concrete box culverts, round culverts, and prefabricated bridges. The life cycle (net present value) analysis identified the cheapest options from a life cycle perspective, but the bridge structure vs. a concrete box structure was still too close to call after refining all of the design variables. The County decided to build a bridge structure because of the better flow characteristics versus a concrete box culvert.
A CP rail line ran along the east side of the canal, and came within 13 m of the east bridge abutment. Directly past the rail line was a major intersection with the divided Highway 4 (North-South Trade Corridor). Hence, communication with the two stakeholders (CP Rail and Alberta Transportation) was a critical factor in the success of the project.
The other (west) side of the bridge a sharp bend in the road, with a residence on either side, thereby creating a tight alignment that required significant analysis during the design stage to ensure the final product met road and guardrail standards.
The new bridge structure is an excellent solution for Lethbridge County which allows their bridge program to realize its maximum efficiency at the lowest cost. At Roseke Engineering Ltd. we love to assist Counties in making their bridge programs more efficient, cheaper, and effective.
We are here to help you deliver your bridge program efficiently and cost effectively. Our bridge team specializes in County/M.D. bridges:
Bernie Roseke, P.Eng., PMP is the founder and president of Roseke Engineering Ltd. He has 20 years experience in the design of rural bridges, culverts, and drainage structures, primarily for Counties, M.D.’s and Alberta Transportation.
Levi Ober, P.L.(Eng.) is our bridge manager and responsible for delivering bridge projects on time and budget. He has 14 years experience in the assessment, design and construction supervision experience on County, M.D. and Alberta Transportation bridges. He has designed every type of standard bridge and bridge sized culvert, and he is a certified class B bridge inspector.
Riley Johnson, T.T. is our junior bridge technologist. He has assisted with design and performed construction supervision services on numerous bridge projects, and his enthusiasm for bridge work is very high.