Refurbishment SBB service facility, Biel

The project
The wooden structure of the Biel service facility was generally in good condition during the inspection. The existing shrinkage cracks have no influence on the load-bearing behavior and the residues of mold are negligible. However, the condition survey and the structural calculations showed that action was needed in the arch trusses, purlins as well as the wind bracing. Due to the lack of bracing, the overall stability as well as the structural safety in the load cases earthquake and wind was not guaranteed.

The construction
The supporting structure was strengthened with transverse tension reinforcements, additional rafter purlins made of GL70 beech and new tie rods. Where necessary, a secondary supporting structure consisting of under-spanned arched trusses with rafter purlins was installed. Furthermore, various structural elements were replaced.

The challenge
As the building is a listed building, the structure was to be upgraded with minimal intervention. In order to satisfy the different needs of the parties involved (engineer, client, preservation of historical monuments), Timbatec worked out various renovation options. In the end, a coherent solution was found.