Balmer Transformer Station
The Balmer transformer station is housed within a masonry tower featuring large openings on several sides. In 2024, LEO Consulting was commissioned to assess the global seismic safety of the facility.
Based on the available drawings, site photographs and information collected on site, the structure was analysed with regard to its seismic behaviour. Due to limited material information and the geometry of the tower, a simplified mechanical model was adopted, which is suitable for vertically oriented structures such as towers. Particular attention was given to the influence of the openings on the lateral load-resisting system and the seismic behaviour in both principal directions.
The assessment followed a risk-informed approach. In addition to the structural evaluation, potential scenarios involving life safety, economic losses and operational impacts were considered. Alongside the requirements of SIA 269/8, international guidelines supporting such risk-based evaluations were also taken into account. The resulting scenario analyses provided transparency regarding the potential operational and economic consequences of a seismic event.
Throughout the project, the owner was informed about the relevant risks. The results provided a transparent and risk-informed basis for decision-making, particularly with regard to the remaining service life, economic proportionality and potential measures to improve seismic safety.