负载下轴压加固柱受力性能试验

Axial Compression Behavior of Column While under Load

为了进一步研究负载下外包钢筋混凝土法加固钢柱的轴压力学性能,进行了7根加固柱和1根纯钢柱的轴压静载试验.试验主要考虑初始负载大小、混凝土强度及箍筋直径三个参数对构件受力性能的影响.由试验得出加固柱在轴心载荷下的破坏形态、载荷-位移曲线及载荷-应变曲线,分析了加固柱的破坏机理和三个变化参数对其轴压性能的影响,提出了加固柱轴压承载力计算公式.结果表明,加固柱的承载力随配箍率和混凝土强度的提高而明显增加;初始负载越大,钢筋混凝土应变滞后现象越严重,加固柱承载力越低.加固柱轴压承载力的计算时对新增部分材料的强度应进行一定的折减.

In order to further research the mechanical properties of reinforced columns, experiments of seven reinforced columns and one steel column under monotonic axial compression are carried out. Three related parameters, the initial load size, concrete strength and stirrup diameter, are concerned. The failure patterns, load-displacement curves, and load-strain curves are obtained. The influences of three parameters on axial compression behavior are analyzed. The formula for axial compression load of reinforced column is presented. The results show that the bearing capacity of the column increases significantly with the increase of stirrup ratio and concrete strength. The strain hysteresis of reinforced concrete becomes greater and the load-carrying capacity becomes lower with the increase of initial load. A certain reduction should be done for the new materials in the calculation of axial compression bearing capacity of the reinforced column.