Title:
The Implementation of Fire Resistance Recommendations in ACI Code-440.11
Author(s):
Mark Green
Publication:
Web Session
Volume:
ws_S24_MarkGreen.pdf
Issue:
Appears on pages(s):
Keywords:
DOI:
Date:
3/24/2024
Abstract:
Glass fiber reinforced polymer (GFRP) bars are a viable solution for corrosion-prone steel bars in reinforced concrete structures. However, the fire performance of GFRP reinforced concrete has been a major concern due to the degradation of GFRP material properties at high temperatures. The consideration of fire resistance in GFRP reinforced concrete has come a long way from not recommending GFRP internal reinforcement for structures, in which fire resistance is essential to maintain structural integrity, to providing design provisions to achieve the desired fire resistance. The former was from ACI 440.1R (2006) and the latter is from ACI CODE-440.11-22. Canadian standard CSA-S806-12 provides a semi-empirical approach for determining the fire resistance of FRP reinforced concrete slabs based on the minimum concrete cover which is overdue for an update incorporating the recent advances in the field. Several full-scale fire tests have shown that GFRP reinforced concrete structures can maintain stability in a fire if measures have been implemented. Past experimental studies aimed to represent the behavior of common GFRP reinforced concrete members such as with bar splices in the fire-exposed regions. The results had shown that the loss of GFRP bond to concrete can cause a premature failure of such members. Later experimental studies avoided the spliced GFRP bars and focused on providing protected cool zones to guarantee adequate bond strength. This study will provide some examples of how to effectively apply the fire provisions in the design of GFRP reinforced beams and slabs. The practical implications of this paper will answer the concerns of designers and GFRP producers on implementing the suggested fire provisions in ACI CODE-440.11-22.