Award of Merit
CEA Showcase Awards 2020
Small Firm - Big Impact

Project Description

Repairs to the existing reservoir and pump station were a major undertaking and required expert knowledge and technical support. To meet the structural needs of the project, our in-house structural team collaborated with Rick Imai, P.Eng. from Ptarmigan Engineering. The combined experience and perspectives allowed our team to explore and understand the original design, previous repair designs, select the best path forward for our repair design, as well as quickly react when concealed conditions were revealed during construction.

Rick Imai started his career in 1973, with over 45 years of experience in the design of water retaining structures. Rick has experienced the evolution of design approaches. At project initiation, our first impressions of the structure were that the slab looked thin compared to current designs. Rick was able to provide perspective on the original structure design approach.

Our structural design team was able to identify issues with the initial design and construction that led to premature failure of different elements. Some of these issues were: not enough concrete cover below the pump station slab reinforcing, slab stress from differing joint conditions along the corners, inadequate beam shear reinforcing, and expansion joints that didn’t line up at roof to wall intersections. These issues were addressed in our repair design by adding concrete cover to repair areas, providing additional reinforcing, decreasing thermal movement with insulation, and adding movement joints to connect the roof joints to the wall joints. The contractor was provided with a detailed concrete repair procedure and quality assurance requirements to confirm that the new concrete would become one with the existing structure.