Structural Strengthening
Structural Concrete Strengthening & Rehabilitation in Ontario
When aging concrete structures can no longer carry required loads — or when deterioration has compromised structural capacity — the choice is not always demolition and rebuild. Carbon fibre reinforced polymer (CFRP) and fibre reinforced polymer (FRP) systems restore and often exceed original structural capacity at a fraction of the cost and disruption of conventional reconstruction.
The problem aging infrastructure facilities face: Ontario’s industrial and municipal concrete infrastructure is aging. Beams, slabs, columns, and walls originally designed to earlier code standards, or deteriorated by corrosion and decades of service, may no longer meet current load requirements. Engineers and facility owners need rehabilitation options that extend asset life without multi-year capital construction programs.
Where Zimcoat Works in Aging Infrastructure Facilities
Beams & Girders
Externally bonded CFRP laminates bonded to beam soffits to restore or increase flexural capacity. NSM (near-surface-mounted) bars inserted into saw-cut grooves in the concrete cover for shear and flexural strengthening where access is limited.
Columns & Piers
CFRP wrapping to increase confinement and compressive capacity of circular and rectangular columns. Effective for seismic retrofit, corrosion-damaged section restoration, and load upgrade.
Slabs & Decks
FRP laminates bonded to slab soffits to increase flexural capacity for upgraded live load requirements. Used in parking structures, bridge decks, and industrial mezzanines.
Walls & Tanks
CFRP fabric and laminates applied to wall faces to increase out-of-plane bending capacity and provide crack containment in water-retaining structures and industrial tank walls.
Connections & Brackets
FRP and CFRP applied to corbels, haunches, and connection zones to address localized deficiency without reframing. Detailed connection analysis required.
Below-Grade & Submerged Structures
Wet lay-up GFRP (glass FRP) and CFRP systems suitable for application in wet wells, tanks, and below-grade structures where conventional repair access is limited.
Structural Strengthening Systems
| System | Best For |
|---|---|
| Externally Bonded CFRP Laminates | Pre-cured carbon fibre laminates bonded to concrete surfaces with structural epoxy. Highest stiffness-to-weight ratio of any strengthening material. Used for beam flexure and slab strengthening. |
| CFRP Fabric Wraps (Wet Lay-up) | Dry carbon fibre fabric saturated with epoxy resin and applied conformally to irregular or curved surfaces. Used for column confinement, wall strengthening, and complex geometry. |
| NSM (Near-Surface-Mounted) Bars | CFRP or GFRP bars inserted and bonded into saw-cut grooves in the concrete cover. Provides shear and flexural reinforcement with minimal surface profile change. |
| Glass FRP (GFRP) Systems | Lower-cost FRP alternative where stiffness requirements are moderate and electrical non-conductivity or corrosion resistance in aggressive environments is a priority. |
| Structural Crack Injection | Epoxy injection of structural cracks prior to FRP application to restore substrate integrity and prevent FRP bond failure at crack locations. |
| Shotcrete & Concrete Jacketing | For members requiring significant section restoration, reinforced shotcrete jacket restores cross-section and provides a sound substrate for further FRP strengthening where required. |
What a Facility Assessment Includes
- Structural drawings review and original design documentation collection
- Site condition survey: visual inspection, delamination sounding, cover depth measurement, carbonation testing
- Structural analysis to confirm deficiency type and quantify required capacity increase
- Collaboration with your structural engineer of record or referral to qualified structural engineer
- Work access assessment: scaffolding, confined space, traffic management requirements
- Written scope including repair sequence, FRP system specification, and budget estimate
Common Questions from Aging Infrastructure Facility Teams
- When is structural strengthening the right choice versus rebuilding?
- Strengthening is typically advantageous when the existing structural geometry is sound, the deterioration is localized rather than global, and the facility cannot tolerate the disruption of demolition and reconstruction. A qualified structural engineer must confirm that the existing member can serve as a substrate for the strengthening system. Where deterioration has progressed to the point of global section loss or inadequate substrate strength, partial or full replacement is warranted. We provide an honest assessment.
- How does CFRP compare to traditional strengthening like steel plate bonding or section enlargement?
- CFRP has a tensile strength approximately ten times that of structural steel at one-fifth the weight. It does not corrode, is non-magnetic, and can be installed in confined spaces that steel plate cannot access. Concrete jacketing adds significant dead load and changes member geometry. CFRP is typically faster to install, causes less disruption, and is the preferred solution for most strengthening applications where the required capacity increase is achievable without section enlargement.
- Do you work with our structural engineer or provide engineering in-house?
- Zimcoat installs structural strengthening systems under the direction of a licensed structural engineer of record. Where clients have their own structural engineer, we work from their strengthening design. Where clients need a structural engineer, we can refer qualified firms in Ontario experienced with FRP strengthening. We do not provide structural engineering services directly.
- How long does structural strengthening work take?
- A single-beam CFRP strengthening can be completed in 1–3 days once surface preparation is complete. Multi-element programs in operational facilities are phased over weeks or months depending on access, structural sequencing, and operational constraints. Epoxy cure time (typically 7 days to full strength at 20°C) governs the loading timeline after installation.
Discuss Your Structural Rehabilitation Project
Bring us your structural drawings, inspection reports, or just a description of the problem. We will assess the scope, advise on the right approach, and develop a rehabilitation plan.
Request a Facility Assessment Call 905.450.2989