Bond behavior between deformed steel bars and recycled aggregate concrete after freeze-thaw cycles. (30th January 2020)

• Record Type: Journal Article
• Authors: Liu, Kaihua; Yan, Jiachuan; Meng, Xiangxin; Zou, Chaoying
• Is Part Of: Construction & building materials. Volume 232(2020)
• Publication Date: 2020-01-30
• Subjects: CDW construction and demolition waste -- NAC natural aggregate concrete -- RAC recycled aggregate concrete -- RCA recycled coarse aggregate -- NCA natural coarse aggregate -- FTC freeze-thaw cycle; Bond behavior -- Recycled aggregate concrete -- Freeze-thaw cycles -- Bond strength -- Bond stress-slip; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2019.117236
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: The bond behavior between RAC and deformed steel bars after FTCs was investigated. The bond stress distribution for RAC after FTCs was discussed. A bond stress-slip model for RAC after FTCs was proposed and verified. Abstract: In cold regions, freeze-thaw damage can deteriorate the structural performance of reinforced concrete structures. This paper investigated the bond behavior between recycled aggregate concrete (RAC) and deformed steel bars after freeze-thaw cycles (FTCs). Sixty-three specimens for pull-out tests were prepared with three different recycled coarse aggregate replacement ratios (0%, 30% and 50%) and seven different FTCs (0, 50, 100, 150, 200, 250 and 300). Additionally, nine made-to-measure pull-out specimens with built-in strain gauges were tested to tentatively study the bond stress distribution along the interface between the steel bars and the RAC after the FTCs. The results show that as the FTCs increased, the bond strength decreased and became increasingly significant as the RCA replacement ratios increased, while the bond slip was relatively stable as the FTCs increased and exhibited a similar increasing trend for all the mixtures at the higher number of FTCs. The bond stress focused on local areas and formed local stress concentrations when the pull-out force was close to the peak value. Finally, a two-segment bond stress-slip model to describe the bond behavior between RAC with RCA replacement ratios less than 50% and deformed steel bars after FTCs was proposed, showing a good correlation with the test results.