Teräsrunkoja

Teräsrunkoja is a type of reinforced concrete structure often used in Finland for above-ground and below-ground water tanks. The design is characterized by a steel cage that encases a rectangular concrete slab. The steel cage serves to reinforce the concrete and provide additional strength to withstand the internal pressure of the water stored within the tank.

The use of teräsrunkoja in Finnish water storage facilities dates back to the early 20th century, following the introduction of reinforced concrete construction. The steel cage typically consists of a series of tapered beams that are typically spaced 50 to 100 millimeters apart. This arrangement is designed to efficiently transfer compressive forces to the surrounding concrete.

One of the key advantages of teräsrunkoja is its ability to be constructed with relatively simple materials and labor. The lack of need for complex forms or molds allows for more cost-effective construction, making it an attractive option for budget-conscious construction projects. Additionally, the covered nature of the tank's structure means that the water is protected from the elements and various waterborne contaminants, ensuring that the stored water meets required quality standards.

The durability of teräsrunkoja structures is relatively high due to their resistance to various environmental factors, such as frost and freezing. Maintenance of these tanks typically involves periodic inspections to check the structural integrity of the steel cage and surrounding concrete.