Cooling Tower Foundation & Structural Support, Ottawa

A cooling tower system needed a modified concrete pad engineered to carry its steel framework, and the site fought back. Dense blue clay subgrade made the required 98% compaction hard to reach. This is a foundation job that came down to solving the ground before pouring anything. 

The pad had to support the full steel framework of a cooling tower, but the subgrade was dense blue clay, which made achieving the required 98% compaction particularly difficult. Get the sub-base wrong and the whole structure is exposed to shifting over time, so the ground had to be corrected before any forming started. 

The team over-excavated an additional foot of clay and replaced it with layered 4-inch stone wrapped in filter cloth, building a stable 3-foot sub-base. After successful compaction testing on both sub-base and base materials, they formed the main pad with integrated piers engineered to carry the steel framework. The design included high-load rigid insulation beneath a 12-inch slab, with columns reinforced by a dense double rebar mat for long-term stability and resistance to shifting. Once poured, the pad was tarped and heated to meet curing conditions and pass concrete strength tests, then the team moved on to forming and pouring the structural columns. 

Despite unexpected challenges, the team held the schedule, including weekend work, and advanced to the final stages, using specialized equipment to assist with the precise installation and connection of the cooling tower. 

• Structure: cooling tower foundation and structural support
• Subgrade challenge: dense blue clay, 98% compaction required
• Sub-base: 1 ft over-excavation, layered 4-inch stone in filter cloth, 3-foot stable build-up
• Slab: 12-inch with high-load rigid insulation beneath
• Reinforcement: dense double rebar mat, engineered piers and columns
• Curing: tarped and heated, passed concrete strength tests
• Scope: excavation, forming, concrete, structural columns, equipment set
• Location: Ottawa and surrounding areas

Have a foundation or equipment pad with tricky ground conditions? Send the drawings or site details for a quote. Call or text (613) 370-0158.