Experimental investigation on axial compressive behavior of ultra-high performance concrete (UHPC) filled glass FRP tubes. (20th November 2019)

• Record Type: Journal Article
• Authors: Tian, Huiwen; Zhou, Zhen; Wei, Yang; Wang, Yongquan; Lu, Jiping
• Is Part Of: Construction & building materials. Volume 225(2019)
• Page Start: 678
• Page End: 691
• Publication Date: 2019-11-20
• Subjects: Ultra-high performance concrete (UHPC) -- FRP tube -- Confinement -- Axial compression -- Experiments; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2019.07.204
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: 54 UHPC filled FRP tubes are tested under axial compression. Effects of steel fiber of UHPC and FRP fiber orientation are investigated. Effects of curing regime and specimen end condition are also investigated. Failure modes, ultimate conditions and stress–strain relationships are discussed. Abstract: To investigate the axial compressive behavior of ultra-high-performance concrete (UHPC)-filled fiber-reinforced polymer (FRP) tubes, a total of 54 specimens, including 42 UHPC-filled glass FRP (GFRP) tubes and 12 unconfined UHPC specimens, were prepared and tested under axial compression. The effects of curing regime, steel fiber in the UHPC core, fiber orientation of the outer FRP tube, and specimen end condition during loading were examined. The test results indicate that UHPC-filled FRP tubes can exhibit highly ductile behavior and a significant enhancement in compressive strength, compared to the unconfined specimens. However, the axial compressive behavior of UHPC-filled FRP tubes is influenced by numerous factors. Hot-water curing can improve the performance of specimens unless the contribution from the enhancement of the UHPC core exceeds that from the damage of the outer FRP tube. Specimens without steel fibers experience a sudden strength loss in the transition region of the axial stress–strain relationship, and exhibit lower ultimate strength and strain than the steel-fiber-reinforced specimens. The test results indicate that aligning fibers in the hoop direction is the most effective way of improving the compressive performance of the specimens. Regarding specimens with thicker FRP tubes, loading the FRP tube can lead to a clear decrease in specimen ultimate strain; however, the influence of specimen end condition can be ignored for specimens with thinner FRP tubes.