Réservoir d’eau « Königshof »

A new drinking water reservoir for civil use is being built in the Swiss municipality of Rüttenen in the canton of Solothurn. The construction company in charge of the work must of course ensure compliance with safety rules, which are numerous in Switzerland, but that’s not all…

A regional energy supplier commissioned Marti AG to build the “Könighof” reservoir. With a capacity of 6,000 m³, this reservoir should ensure the region’s drinking water supply for the next 100 years and be used to store the fire reserve. After completion of the work, the new reservoir will replace two old installations and will no longer be visible at all, as it is well hidden underground. The structural work, carried out by the team of site manager Liridon Haxhimurati and team manager Peter Kaufmann, began in February. The well-known construction company relied on the production capacity of the Mammut 350 wall formwork, the reliability of the SecuritBasic safety system and, for the casting of the columns, on the ease of use of CaroFalt.

The 60 m long, 30 m wide and 13 m deep excavation was carried out in January 2021. The excavation of the very hard sedimentary rock of the puddingstone was difficult and time-consuming. The floor area of the tank is 51 x 26 m. There was therefore little space left for the installation of the equipment, the storage and the maintenance of the equipment on this cramped site, located in the middle of the countryside and only accessible by a forest road. It was in particular the installation of the high-rise formwork and the installation of the SecuritBasic security system that were complex to achieve in this limited space. Several Mammut 350 panels were therefore assembled, including the SecuritBasic platforms, to achieve 7 m high formwork trains and facilitate formwork craneage after each casting.

Particularity of the project: the formwork of the very thick corner walls which, to be reinforced, were made with

with a 45° angle on the inside. i
To withstand the heavy loads in the corners, the fresh concrete pressure resistance of the Mammut 350 formwork has been increased from 100 KN/m² (usually) to 80 KN/m². The formwork was also stabilized using corner stiffeners specially designed for this purpose so as to perfectly control the strong pressure exerted by the concrete in these difficult areas. The Mammut 350 formwork and the CaroFalt column formwork were covered with fleece strips to drain excess water from the facings. At the level of the rod passages, waterproof sleeves were embedded in the concrete.

Workers on a construction site in Switzerland must apply the prevention principles of the SUVA (Swiss national insurance fund in the event of accidents); on the construction site of the “Königshof” reservoir, they also had to comply with the prescriptions of the SSIGE (the professional association of distributors of gas, water and remote heat). MARTI construction companies are familiar with MEVA technologies thanks to the many projects already carried out together, often very complex projects.