Fire resistance tests on thin CFRP prestressed concrete slabs

• Novel, optimised CFRP prestressed concrete elements offer great potential.
• Fire performance of CFRP prestressed concrete elements, which is not well known, is investigated in detail.
• Propensity for concrete spalling may be influenced by in-depth temperature distributions.
• Loss of anchorage of CFRP tendons is critical, and is fundamentally influenced by their temperature.

Optimised, high-performance concrete elements, prestressed with carbon fibre reinforced polymer (CFRP) tendons offer great potential within the sustainable modern built environment. However, the performance of these elements in fire is not well known and must be better understood for applications where fire resistance is required. Findings from large-scale fire resistance tests on thin CFRP prestressed concrete slabs are presented and discussed. Results show that explosive spalling in fire results in sudden collapse, and when spalling is avoided failure occurs by loss of anchorage, which is in turn governed by the temperature of the tendons.