Abstract
In order to improve structural thermal performances, this paper designed a two-layered functionally graded concrete (FGC) slab composed of an ultra-high performance concrete (UHPC) layer and a lightweight aggregate concrete (LWAC) layer. UHPC layers are used as structural layers to bear loads while LWAC layers are used for thermal insulation. Fire tests were conducted to investigate the fire resistance behaviors of the FGC slabs with different LWAC thicknesses under the ISO834 heating regime while homogeneous UHPC and normal concrete (NC) slabs were prepared as a contrast. The experimental results revealed that the LWAC could significantly reduce the temperature transferred to UHPC layers, where the interfacial temperatures of FGC slabs with 40 mm and 30 mm thick LWAC layers were 197 °C and 325 °C respectively. Meanwhile, the maximal mid-span deflections ranged from 26.1 mm to 31.5 mm respectively, approximately 55%-65% lower than those of homogeneous material specimens. Besides, FGC slabs presented good explosive spalling resistance, no delamination or debonding occurred at interfacial regions, and LWAC layers adhered to UHPC layers in the form of “multi-point attachment”. The studies provided a solution to the fire resistance design of reinforced concrete structures under high temperature based on the structural level, and the thickness of LWAC layers was optimized by finite element analyses.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
