Analysis on bonding failure model between reinforcing steel and all-lightweight concrete based on pull-out tests
YANG Jianhui
YANG Nianxu
LIN Xinyan
ZHANG Han
Abstract：In order to investigate bond-slip (BS)behaviors of hot rolled crescent-shaped bars (HRCSB)and hot rolled plain steel bars (HRPSB) in all-lightweight concrete (ALWC),the pull-out (PO) tests were carried out under different conditions in the paper.PO force (F)-displacement (S) curves were gained and failure modes were observed.The results show that the PO failure (POF) is found in PSB,while the POF and splitting failure (SF) are found in CRB.Based on the analysis of the above failure modes and the transformations of bond stress (BS)with (τ)-displacement (S)curves by F-S curves,the bond failure (BF)mechanism and the BS curves are found similar with normal weight concrete (NWC).Therefore,the classic τ-s curves adapted for ALWC are given.Although the BS increases with the strength of concrete and the diameter of reinforcement increasing,and for the CRB,the contribution of mechanical bite force between the crescent rib and concrete to BS is more than 95 percent.However the PO force will generate retraction when the diameter is 20 mm.A physical-mechanical analysis model on CRB is put forward based on the characteristics of crescent rib and the corresponding mechanical models are also derived according to different stress stages.The relations between the diameter of CRB and equivalent radius is given,which is verified correct by test data.
Keywords：all-lightweight concreteplain steel-bars and crescent ribbed barscrescent ribbed barspull-out testbond stress-displacement modelequivalent radius
Publication Date：2018-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 117-124,138 )