Experimental study on the behavior of recycled-concrete-segment/lump filled steel tubular stub columns subjected to concentrically axial load
Wu Bo1 Liu Wei1 Liu Qiongxiang2 Xu Zhe1(1. State Key Laboratory of Subtropical Building Science,South China University of Technology,Guangzhou 510640,China;2. Shenzhen General Institute of Architectural Design and Research,Shenzhen 518000,China)
In order to investigate the axial compressive behavior of recycled-concrete-segment/ lump filled steel tubular (RCS/LFST) stub columns,based on the tests of 17 specimens,the 7d and 28d axial mechanical properties of RCS/LFST stub columns and concrete filled steel tubular (CFST) stub columns are studied,and a comparison is conducted for stiffness,strength and ductility of the two kinds of stub columns. According to the domestic and foreign design codes for CFST structures,the axial load bearing capacities of the specimens are calculated and compared with the test results. Then a suitable formula is chosen to determine the axial ultimate strength of RCS/LFST stub columns. Test and simulation results show that:(a) although 30% ~ 35% of the concrete used in the RCS/LFST specimens is demolished concrete,the axial mechanical properties of these specimens are almost the same as those of the CFST specimens; and (b) the axial load bearing capacities of the RCS/LFST specimens calculated according to the domestic standard JCJ 01—89 are in good agreement with the test results.