高温后方钢管再生混凝土偏压柱受力性能试验

TEST OF RECYCLED AGGREGATE CONCRETE FILLED SQUARE STEEL TUBE COLUMN SUBJECTED TO ECCENTRIC COMPRESSION AFTER HIGH TEMPERATURE

对9个方钢管再生混凝土偏压柱在火灾(高温)处理后再进行静力单调加载试验,考察再生粗骨料取代率、最高恒温温度2个变化参数,对试件极限承载力、刚度、位移延性和耗能能力的影响,得到试件受力的全过程和试件破坏形态,获取了极限承载力、荷载-变形曲线、截面应变分布等数据。研究结果表明:高温后方钢管再生混凝土偏压柱受力破坏过程和形态与普通钢管混凝土相似,均经历了弹性阶段、屈服阶段和破坏阶段;温度对方钢管再生混凝土偏压柱的力学性能有显著影响,随着温度的升高,试件的极限承载力、抗压刚度明显降低;而再生粗骨料取代率的变化对试件的力学性能影响不大。

In order to investigate mechanical performance of recycled aggregate concrete filled square steel tube column after high temperature subject to eccentric compression,eccentric compression static monotonic loading test were carried out to nine specimens. Two main influence factors including replacement rate of recycled coarse aggregate and highest temperature of the specimens experienced were considered. It was observed the whole experiment process and the failure modes of the specimens,and got some important information such as ultimate bearing capacity,loaddeformation curves and cross section strain distribution. It was analyzed the influence of the changing parameters on the four main mechanical properties including ultimate bearing capacity,compressive stiffness,ductility and energy dissipation capacity. The destructive process was made up of three stages,the elastic stage,yield stage,and destruction stage. The results showed that the highest temperature had great impact on mechanical properties of specimens: with increase of temperature,the ultimate bearing capacity and the compressive stiffness of specimens decreased obviously; while the replacement rate of recycled coarse aggregate had little influence on the mechanical properties of specimens.