- Author
- Lim, L. C. S.
- Title
- Membrane Action in Fire Exposed Concrete Floor Systems.
- Coporate
- University of Canterbury, Christchurch, New Zealand
- Report
- Fire Engineering Research Report 03/2, April 2003, 343 p.
- Distribution
- FOR MORE INFORMATION CONTACT: School of Engineering, University of Canterbury, Private Bag 4800, Christchurch, New Zealand. Telephone: 643-364-2250, Fax: 643-364-2758, Website: http://www.civil.canterbury.ac.nz
- Keywords
- floors | concretes | concrete slabs | fire behavior | exposure | fire tests | reinforced concretes | codes | thermal properties | steels | multi storey building | temperature | fire resistance | structural elements | material properties | construction | storage | load bearing capacity
- Identifiers
- behavior of reinforced concrete slabs under fire conditions; SAFIR (Smoke Gas Analysis by Fourier Transform Infrared Spectorscopy); SAFIR finite element program; compressive membrane action in one-way slab under fire expsoure; experimental fire tests of two-way slabs; analysis of slabs at ambient conditions using the SAFIR shell element; 3D modeling of two-way slab behavior under fire conditions; comparison of SAFIR modeling with test results; behavior of fire-exposed two-way slabs with various support conditions
- Abstract
- The behaviour of reinforced concrete slabs in fire conditions strongly depends on the support conditions and the interaction of the slabs with the surrounding structure. Previous research has shown that compressive restraint forces from the surrounding structure can increase the fire resistance of heated slabs, and fire resistance can also be considerably enhanced if tensile membrane behaviour is mobilised. This study was carried out to investigate the effects of compressive membrane action and tensile membrane action on the behaviour of reinforced concrete flat slabs in fire conditions. The investigation into compressive membrane action was performed on single span, one-way flat slabs with a non-linear finite element program, SAPIR. The slabs were subjected to the ISO fire from below. The height of the line of thrust at the supports and the axial restraint stiffness were varied to model different support conditions. The investigation on tensile membrane action was performed on unrestrained two-way flat slabs and composite slabs. The study was performed with experimental fire tests and 3D finite element analyses with SAPIR, which was used to predict the behaviour of the tested slabs and also used to model different slab configurations. The experimental fire tests were carried out for six reinforced concrete and composite steel-concrete slabs on a fire resistance furnace, each of them exposed to the ISO standard fire while carrying a live load.