从结构的边界条件入手,利用经典力学原理,分析了不同边界条件异形柱的力学特性,结果表明:异形柱截面不对称,即使在单向弯矩作用下,两端铰接以及一端固接一端铰接的异形柱也会产生双偏压特性,而两端固接的异形柱则是产生单偏压现象.并对"悬臂柱式"和"建研式"加载的异形柱低周反复荷载试验现象给予了理论上的分析和诠释;设计相关试验对理论分析结果进行试验验证,得出以下主要结论:"建研式"加载的低周反复荷载试验是对框架结构中异形柱力学性能的合理模拟,框架结构中异形柱的力学性能是单偏压特性以及滞回曲线对称,其破坏主要由承载力薄弱一侧的上下端部控制.
Based on the boundary conditions and the typical mechanical principle of the structure,the mechanical behaviors of special-shaped columns under different boundary conditions are analyzed.The special-shaped columns,where both are hinged or one is hinged and the other is fixed,showing the characters of two-way eccentric compression even under single-way moment and the both-ends fixed columns bring the performance of single-way eccentric compression.According to the results,the two types of special-shaped column experimental phenomena can be explained.Using different test setup to produce cyclic loading,one is for cantilever column loading device,and the other is a parallel crosshead equipment.The following conclusions can be drawn from theory etical analysis and experiment study: the experiment using parallel crosshead equipment can simulate mechanical behavior of special-shaped columns in the frame structure well.The special-shaped columns in the frame structure are a one-way eccentric compression under single-way moment.Hysteretic curves are symmetric and the destruction mainly took place near the top and the base side where the bearing capacity is weak.