Construction products detail

The construction techniques described here include, e.g.:

Construction techniques comprising steel fibre-reinforced concrete

• Steel fibre reinforced members solely reinforced by pretressed reinforcement and subjected to normal force, shear force and/or bending, e.g. wall elements, floor elements or prestressed beams.
  The steel fibres serve to resist the shear and splitting forces in the area in which the prestressing force is introduced. They can serve as a required minimum reinforcement in terms of a surface reinforcement, as a transverse reinforcement and/or for crack width control. DIBt decisions in this area primarily serve to provide design and execution specifications in the event of deviations from the provisions set out in the DAfStb Guideline on steel fibre concrete (DAfStb-Richtlinie Stahlfaserbeton). The application is currently restricted to predominantly static loads. Upon request, fire protection properties can also be comprehensively covered where relevant fire safety requirements exist.

Construction techniques comprising textile-reinforced concrete, e.g.:

• Sandwich walls comprising a load-bearing inner leaf made of reinforced concrete, thermal insulation layer, textile-reinforced outer leaf made of normal weight concrete and textile connection system, currently only for static and quasi-static loads
• Walls and floor construction techniques for tiny buildings made of textile-reinforced concrete, of various basic types, special provisions for fire protection possible

• Textile-reinforced floor elements, slabs subject to bending and shear loading below the design limits set out in DIN EN 1992-1-1 for strenghtening other structural members.

Regulatory framework

DIBt grants national technical approvals (abZ) for non-regulated beams, floor and wall elements made of steel fibre reinforced concrete, usually in combination with general construction technique permits (aBG) for the design and execution of the related construction techniques.

Regulatory verification of the fitness for use and/or application is required, in particular, when the elements are manufactured without the minimum amounts of reinforcing steel ('combined reinforcement') set out the DAfStb Guideline on steel fibre concrete (DAfStb-Richtlinie Stahlfaserbeton). A regulatory verification of fitness for use is also required when fibres not covered by DIN EN 14889, Parts 1 and 2, are used. You may apply for a national technical approval to obtain such verification of fitness for use. European Technical Assessments (ETAs) can also be issued for such fibres.

Note: The durability of fibre-reinforced concrete manufactured using plastic fibres cannot be declared in accordance with DIN EN 14889-2:2006-11. The building authorities recommend separate verification of this characteristic in the technical documentation. Upon request, DIBt can issue a European Technical Assessment or an evaluation of fitness for use in this respect on a voluntary basis.

Elements made of textile-reinforced concrete and non-metallic bar reinforcement have not yet reached sufficient maturity for standardisation. Regulatory verification of fitness for use is required. Because generally accepted design and execution rules are also missing, the construction technique is also considered to be non-regulated.

Upon request, DIBt grants national technical approvals for non-metallic bar reinforcements covering the properties, composition, field of use as well as the external surveillance of the reinforcement products. In a general construction technique permit included in the decision, design and execution specifications for the corresponding construction techniques are given.

DIBt also approves elements reinforced exclusively with textiles or with textiles in combination with other forms of reinforcement upon request. Any necessary specifications concerning the design, execution, use and maintenance as well as connection of the elements to other parts of structural works can be added to the decision in the form of a general construction technique permit.

In principle, DIBt can also issue ETAs for elements made of textile-reinforced concrete and non-metallic bar reinforcements. These would cover the characteristics of these construction products in relation to the basic requirements for construction works. Design and execution provisions for the installation of the products in specific structural works can currently only be established in light of detailed application conditions. A construction technique permit is required for this.