钢管再生混合短柱的轴压性能试验

Experimental study on the behavior of recycled-concrete-segment/lump filled steel tubular stub columns subjected to concentrically axial load

为揭示钢管再生混合短柱的轴压性能,通过17根试件的轴压试验,考察钢管再生混合短柱与钢管混凝土短柱的7d和28d轴向受力行为,比较二者的刚度、强度和延性。根据国内外钢管混凝土结构设计标准,对试件的抗压承载力进行计算,基于计算结果与试验结果的对比,建议钢管再生混合短柱的抗压承载力计算公式。研究结果表明:①虽然钢管再生混合短柱采用了32%～35%的废弃混凝土,但其轴向受力性能却与全现浇钢管混凝土短柱相当。②根据我国标准JCJ01—89给出的钢管再生混合短柱的抗压承载力计算结果与试验结果吻合较好。

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.