7.3.1.1 General requirements

Reinforced concrete structures with high resistance to water penetrating prevent water penetrating permanently in liquid form. As well as bearing loads, they also act as structural waterproofing.

Designing and constructing white tanks in Germany is governed by the DAfStb’s guidelines on ‘Water-impermeable concrete structures’, (WU guidelines) [98], as the generally accepted rules of the art. The WU guidelines provide instructions on requirements for fitness for use of water-impermeable reinforced concrete structures. DAfStb vol. 555 ‘Explanatory notes to the DAfStb guidelines’ [99] contains notes to the WU guidelines. Instructions are contained in DBV bulletin on ‘High-grade use of basement floors — building physics and indoor climate’ [100].

There are a number of constraints to be considered when building a white tank:

— nature of the moisture penetration

— design water levels

— type, characteristics and permeability of the subsoil

— chemical characteristics of the water

— establishing the type of use involved, particularly in the light of the stresses and special loads from external and internal events.

Supplementary drainage measures may be taken to protect the structure, particularly against non-pressured water or temporarily accumulating water. For drainage design, dimensioning and execution rules, see DIN 4095 [101].