Westbrook Pedestrian Bridge
Location: Calgary, AB
The area surrounding Westbrook mall was identified as a major activity center by the City of Calgary due to the Westbrook LRT Station and steadily increasing volume of pedestrians. The existing overpass crossing Bow Trail between 33rd and 37th Street S.W. was constructed in 1970, at a time when accessibility standards were much lower than they are today. Approaching 50 years old, the bridge was exhibiting significant deterioration and had numerous structural deficiencies.
The $6.7 million Westbrook Pedestrian Bridge Replacement Project (WPB) included the construction of a new coated steel bridge structure that ties into precast arch ends before transitioning to the curved wingwalls along the abutments. The new accessible ramps were constructed with a cast in place deck supported by conical pier sections. The four sections of the steel structure were fit up to the precast ends using temporary shoring designed by Ryan Loewen, who is the Project Engineer proposed for the Jaipur Bridge. Steel towers were designed and engineered to provide support for each of the connections while allowing for adjustments during fit up to match the angles of the abutment tie in points.
Handrail: Over 575 lineal meters of galvanized handrail was fabricated and installed on this Project. To accommodate the landing, stair, ramp and bridge geometry, unique part numbers were given to rails and posts of different shapes and sizes. For ease of installation on site, the part numbers were written right on the pieces with removable paint markers. This seems like a minor detail, but it turned out to be a large effort to remove these markings with a couple slight blemishes on the handrail left. During installation of the handrail on the Jaipur Bridge, special attention will be given to the handrail shop drawings layout to make sure an efficient plan is thought of for site installation. If part numbers are needed to be identified on site, marks will not be put on either the stainless or galvanized components or concrete deck. Tape or removable tags will be used instead. Specific luminaire attachments integrated in the handrail base will also be given special attention. On the Westbrook Project, the luminaires were set right in the grabrails and self-tapping screws were required to align the angle of the lights. This self-tapping screw method did not always secure the grabrail as some screws came loose, causing the grabrail to spin. A design that allows for a quick and correct luminaire attachment and alignment that is not affected by coating thicknesses will be something Graham will look out for when reviewing the handrail shop drawings on Jaipur Bridge. Deck Finishing: In order to open the project to the public as soon as possible, application of the silane sealer was required in winter months. Special care and attention was needed to ensure the deck was clean and free of ice and moisture before application. At some points the deck needed to be heated and tarped to achieve the proper temperature resulting in additional project costs and resources. For the Jaipur Bridge schedule, finishing work was pushed as far into Spring 2022 as reasonably possible to avoid Winter weather and ensure a quality finish on the concrete surfaces. The North stairs will be completed in summer/fall 2021 for this same reason. Arch Assembly and Dimensional Checks: Time spent in the early stages planning and coordinating with Subcontractors on their particular scopes was time well spent on the WPB Project. Coming up with an effective plan and schedule and communicating that plan clearly to the Subs to get their feedback and buy in helped keep the critical integration of the different bridge elements running smoothly.
Attention to detail on things like shop drawing reviews and dimensional hold point checks ensured the overall targeted design dimensions were never in question. It was never a guessing game of how elements were going to fit together, and Graham will take that success and lessons learned of efficient front end planning into the Jaipur Bridge Project as well. Partnering with the Project Team and using RJC and the City’s Project Manager Dwain Babiak as a resource to collectively come up with effective plans also contributed to this success. Once all parties of the Project started to trust each other’s skill sets, we were able to work together to collaborate and support what was best for the successful early opening and completion of this signature pedestrian bridge. This partnering and collaborative approach will be brought to the Jaipur Project.
Read Jones Christoffersen
City of Calgary