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Indexed by:Journal Papers

Date of Publication:2019-09-01

Journal:KSCE JOURNAL OF CIVIL ENGINEERING

Included Journals:SCIE

Volume:23

Issue:9

Page Number:4000-4009

ISSN No.:1226-7988

Key Words:CFRP; high-strength concrete; expansive agent; prestress; intercept stress; peak stress

Abstract:Due to the advantages of FRP (fiber reinforced polymer), such as light weight, high strength and corrosion resistance, FRP-confined concrete columns are gradually applied in civil engineering structures and have drawn wide attention from the engineering community. In order to avoid the stress hysteresis of CFRP (carbon fiber reinforced polymer) and make full use of FRP materials, expansive agent was added to concrete to make self-stressing high-strength concrete. In this study, the axial compression performance of 18 CFRP-confined self-stressing high-strength concrete cylinders was examined. The parameters include the CFRP layers and the level of prestress (with or without prestress). Experimental results show that 3.53-5.34 MPa prestress in concrete and 799.3-1584.2 MPa prestress in CFRP are produced in the composite cylinder. The stress-strain curves obtained from the experiment shows that the intercept stress, inflection stress and peak stress of the self-stressing specimens are all higher than those of the non-prestressed specimens. With the application of prestress, the utilization ratio of CFRP increases as well. In the theoretical calculation of intercept and peak stress, by modifying the existing models, the experimental results are in good agreement with the calculated results.