In the oil, gas, chemical and petrochemical industries, concrete structures generally comply with regulations. However, they are not evaluated or tested, at least with respect to concrete structures that form the foundation for processing plants or other structures.

To prevent escalation of fire in and damage to the installations and to keep production breaks to a minimum it is essential that the capacity of a concrete structure is maintained during a fire. A thorough evaluation of the fire resistance of concrete can therefore be very valuable. It can also lead to new recommendations for the fire safety of concrete structures in these industries, enabling fire damage to be minimised.

One of the greatest risk during a fire is spalling of concrete. This occurs especially when it is exposed to a rapid temperature rise. Hydrocarbon fires are a good example of this. Efectis Nederland has developed a method of evaluating the fire behaviour of concrete and the passive fire protection of concrete. This test procedure is suitable for concrete structures that have optional protection by means of various passive fire-resistant systems, such as fire-resistant cladding, mortar or polypropylene fibres.

The degree to which concrete spalls depends on the mix and strength of the concrete, the porosity, the moisture content, the form of the concrete, and the loading and heating conditions. These factors have to be taken into account if a good spalling test is to be performed. The basic criterion in this is ‘no spalling’, apart from minimal localised damage. The only way to determine the spalling behaviour properly is to ensure that the test specimens resemble the practical situation as closely as possible.

The new test procedure is called Fire test procedure for concrete structures in Oil & Gas, Petrochemical and Chemical installations (document no. EFTP002:2016) and can be downloaded from the Efectis website: https://efectis.com/app/uploads/2016/11/EFTP-002-2016-Fire-test-procedure-Oil-Gas.pdf

Contact: Tomas Rakovec – [tomas.rakovec@efectis.com]