Notre-Dame Basilica of Montreal
Fabrique de la paroisse Notre-Dame de Montréal
Montreal, Canada
2021-2024
SIMCO (formerly Cosigma) participated to two projects to restore the towers of Montreal’s Notre-Dame Basilica. The Basilica is a major heritage monument of the city, built between 1824 and 1843. Elevated to the rank of minor basilica in 1982 and designated a National Historic Site of Canada in 1989, its religious and artistic significance makes it one of the jewels of Quebec’s heritage.
Management of complex structural pathologies
SIMCO carried out the structural and dynamic analysis of the west tower:
- Detailed inspection
- Dynamic measurements of ambient vibrations from the bells
- Dynamic modeling of the structure
- Analysis of the impact of the vibration on the durability of the masonry
- Plan & specifications for the rehabilitation
- Technical support during the repair work
Historical Repairs and Material Challenges
Due to advanced stone deterioration, numerous prior repairs, variable material properties, and diverse mortars, the work required detailed analysis. The structural assessment was tailored to the heritage nature of the structure and included evaluating dynamic effects from bell and chime activation on masonry degradation. SIMCO further innovated by using in situ dynamic measurements to refine and calibrate the tower’s dynamic model, providing a more realistic understanding of its behavior and thereby limiting the scope of reinforcement interventions.
Quick fact
The innovative methodology applied by SIMCO for the dynamic modeling of the basilica towers was the subject of an in-depth study in collaboration with ÉTS and Mitacs. The research project made it possible to develop advanced methods for modal analysis and numerical modeling adapted to North American and Quebec heritage structures.
