Characterising component failure in composite structures exposed to fire
Lead Research Organisation:
University of Edinburgh
Department Name: Sch of Engineering
Abstract
This PhD project will examine the behaviour of concrete composite construction in fire, focusing upon the performance of slab reinforcement through a combination of modelling and experimental work. Steel-framed construction with composite concrete floor slabs enjoys a reputation as a robust construction type in the fire limit state, as a result of substantial research that has established its alternative load-carrying mechanisms. This was initially prompted by the response of the Broadgate 8 building in fire, leading on to the successful Cardington fire tests in the 1990s, and subsequent research at the Universities of Edinburgh, Sheffield and Manchester. Arup staff have also been active in this research, both as part of the above research institutions and independently as part of their commercial project delivery.
During a fire, the composite floor slabs develop large deflections. Structural stability of the building relies on the bond and strain capacity of the internal steel slab reinforcement. The implications of their behaviour for the overall slab performance at the fire limit state is therefore not fully understood. For example, construction now relies on deformed rebar that provides a high degree of bond with concrete. The Cardington tests were based on smooth rebar and therefore the increased bond of the newer products might reduce the robustness of the building at the fire limit state due to stress concentration across cracks leading to premature rupture of the rebar.
The project will involve numerical modelling to examine heat transfer, mechanical properties, and thermo-mechanical response of the shear studs, reinforcement, and the implications for the composite slab as a whole. Small-scale tests will be conducted within the University's well-equipped fire and structural research laboratories. The outcome of the project is intended to be a library of material properties that can be used for analytical and computational assessment of composite structures at the fire limit state.
During a fire, the composite floor slabs develop large deflections. Structural stability of the building relies on the bond and strain capacity of the internal steel slab reinforcement. The implications of their behaviour for the overall slab performance at the fire limit state is therefore not fully understood. For example, construction now relies on deformed rebar that provides a high degree of bond with concrete. The Cardington tests were based on smooth rebar and therefore the increased bond of the newer products might reduce the robustness of the building at the fire limit state due to stress concentration across cracks leading to premature rupture of the rebar.
The project will involve numerical modelling to examine heat transfer, mechanical properties, and thermo-mechanical response of the shear studs, reinforcement, and the implications for the composite slab as a whole. Small-scale tests will be conducted within the University's well-equipped fire and structural research laboratories. The outcome of the project is intended to be a library of material properties that can be used for analytical and computational assessment of composite structures at the fire limit state.
People |
ORCID iD |
| Tim Stratford (Primary Supervisor) | |
| Russell Wallace (Student) |
| Description | The project is in early stages of developing new test methodology. The research is to improve composite structure design methodology. |
| Exploitation Route | The outcomes may be directly applicable in the design of composite structures / building design. |
| Sectors | Construction |