New recommendations for safer concreteThe adaptation of fire spalling resistant concrete provides safer buildings and reduces the need for fire testing. Instructions on this process are contained in the new recommendations for fire spalling resistant concrete which have been prepared by the Swedish Concrete Association, SP Fire Technology and the Swedish Cement and Concrete Research Institute (CBI).
When compact and damp concrete is exposed to fire it risks cracking, referred to as spalling. This is common in, for example, tunnel fires and causes extensive damages with expensive and long-lasting repairs as a result. Polypropylene fibres are added to the concrete in order to prevent spalling. Prior to delivery the manufacturer needs to carry out fire tests on the concrete based on agreed limit values, which is an expensive and time-wasting process for manufacturers and purchasers.
As a part of targeting this problem, the Swedish Concrete Association established a committee for finding new solutions. CBI and SP Fire Technology have had leading roles in the work group and have performed extensive material and fire tests parallel to the research work. The result was a report with new recommendations which are the first globally to state both when the spalling resistant concrete should be used and also how much polypropylene is needed in the different cases.
Owing to this the manufacturer can deliver concrete which is directly adapted to the fire risk it is exposed to, which increases safety and leads to fire testing only being required in specific cases.
The Swedish Transport Administration already refers to the recommendations in its regulatory framework.