薄壁钢板组合PEC柱(强轴)滞回性能试验研究

目前我国规范关于PEC组合柱构件及由此组成的结构体系方面的有关内容还基本空白,通过了解国际上在PEC组合柱研究领域的现状,对3个变化混凝土强度等级和拉结筋间距的薄壁钢板组合截面PEC柱足尺试件在恒定轴压下进行水平循环荷载的滞回性能试验。观测记录各个试件加载阶段的薄壁钢板组合截面翼缘的局部屈曲和混凝土裂缝开裂与压溃现象,得到构件的荷载-位移滞回曲线。根据试验结果分析构件的承载力、抗侧刚度、构件的抗震延性和破坏模式等力学性能。结果表明:试验试件具有较好的变形能力和耗散地震能的双重功效;构件的破坏模式为薄壁钢板组合截面翼缘发生局部屈曲,随之柱脚部位混凝土压溃和拉结筋屈服甚至拉断。研究进一步丰富了PEC柱研究成果,为PEC组合柱组成的结构体系规范制订和工程应用提供了合理的理论依据。

Hysteretic behavior of PEC columns(strong axis) with thin steel plate composite section

According to the development in the field of partially encased composite columns(PEC) and the demand for modification of the relevant structural specification,PEC columns fabricated with thin-wall composite section were investigated.3 specimens with various concrete strength and transverse link spacing were manufactured to represent the middle-storey column of a PEC column-steel beam composite frame structure.The test of the specimens were conducted under lateral cyclic loading along the strong axis with constant axial compression,and the hysteretic curves were obtained.Base on the test results,the global responses were analyzed,including the load-carrying capacity,lateral-resistant stiffness,energy-dissipation capacity,the ductility property and the failure mode.The specimens exhibited sound ductility and energy-dissipation capacity;the failure mode was primarily local buckling in the flange of a thin-wall composite section,crushing and spalling of concrete at the corner region of the column and yield of the transverse links.