Prestressed concrete tank

Prestressed concrete tanks are usually designed as circular or rectangular tanks with rounded corners. These tanks are often used in the field of waste water technology or as industrial tanks. Due to the inner filling, ring tensile forces are generated in the tank wall, which cannot be absorbed by the concrete and the reinforcement. To overcome these tensile forces, prestressing strands are arranged and pre-stressed inside the tank walls.

The tanks can be installed as in-situ concrete or with prefabricated elements. After the concrete has hardened sufficiently, the tensioning strands are drawn into concreted empty conduits and pretensioned. The effect of creep and shrinkage of the concrete and immediate loss of tensioning force from the tensioning process (wedge slip) must be determined and taken into account. This serves to ensure a sufficient level of prestressing force throughout the entire service life and to overpress the tensile forces in order to prevent leakage.

Other factors are also taken into account in the design. For example, a sufficient crack width limited reinforcement must be inserted. This is usually done by means of small bar diameters at a closer spacing to limit the crack width to the required values. Furthermore, a sufficient exposure class has to be chosen to resist the chemical attacks of the medium or from outside.

Our services

The dimensions for the prestressed concrete tanks are based on the Eurocodes and the respective approvals of the prestressing systems. The following services for tank construction can be provided by SKI Ingenieurgesellschaft:

Static calculations for tanks and foundation slabs
Evidence and assessments concerning the increase of existing tanks
Detailed proofs (e.g. for breakthroughs, connections, punching)
Dynamic calculations (e.g. due to an agitator)
Evidence for earthquake loads
Design of the clamping systems (number, position, preload level)
Numerical simulationsn (z.B. Ermittlung von temperaturabhängigen Dehnungen)
Dimensioning of the foundation (e.g. circular foundations, foundation plates, individual supports)
Anchoring in the foundation (e.g. connection weighting)
Reports in cases of damage and accidents