Reduction of fire spalling of concrete with small doses of polypropylene fibers
(English)Manuscript (preprint) (Other academic)
The addition of polypropylene fibers has been shown to reduce the fire spalling propensity of concrete. This has been proven in many fire tests; but, very few large scale tests exist showing the function of polypropylene fibers at low dosages. In this study results on polypropylene fibers included in w/c 0.40 mixes typical used in tunnel construction that is spalling sensitive without fibers shows that an amount of only 0.6 kg/m3 (1.01 lb/yd3) has a significant effect on the spalling propensity and that even lower amounts reduce the spalling although they do not eliminate it entirely. During one of the fire tests on large slabs loaded in compression, unloaded cubes of the same mixes were also included in the furnace. None of the small specimens spalled whereas some of the corresponding large slabs spalled beyond the layer of reinforcement. This showed that the cube test method is not conservative.
concrete, fire, spalling, polypropylene fibers, admixture, tunnel concrete, fire, spalling, polypropylene fibers, admixture, tunnel
IdentifiersURN: urn:nbn:se:kth:diva-128370OAI: oai:DiVA.org:kth-128370DiVA: diva2:647376
QS 20132013-09-112013-09-112013-09-11Bibliographically approved