Earthquakes occur more often in Switzerland that one may think. But the people living in the affected areas notice only a few of these quakes. Thanks to the dense and highly sensitive network of seismographs to measure earthquakes in Switzerland, even the smallest quakes can be recorded and assessed at most locations in Switzerland.
Slight and moderate earthquakes are noticed by only a few persons outside, but by many people inside buildings. Some people are rudely awakened, crockery and windows rattle, or small objects are moved around. Cracks appear in the walls or plaster of buildings, and loose tiles can fall from the roof. It should be remembered that even minor damage to buildings can give rise to considerable costs.
Vaccines have been manufactured in Thörishaus since the beginning of the 1950s. Today, around two million doses of vaccine are manufactured here every year and Emergent BioSolutions is one of the biggest manufacturers of vaccines against infectious diseases in the world. The vaccine manufacturer is aware of the risk of earthquakes in Switzerland and therefore instructed its long-standing partner Weiss+Appetito AG to strengthen the four basic supports with concrete walls as part of the conversion of "Building 76". This improves the load-bearing capacity and gives the building better protection against earthquakes.
Around 1,000 bores were needed to attach the 5.3 tonnes of reinforcing steel in six stages. The formwork was filled with self-compacting cement pumped from a silo. Care had to be taken that the resulting concrete pressure did not damage the external façade as the concrete slabs were installed from floor to ceiling in the whole building. The entire project was realised on the inside of the existing façade. The project could be successfully completed and handed over after two months.