预应力薄壁钢约束圆木柱轴心受压性能分析

Axial compression performance analysis of prestressed thin⁃walled steel confined circular timber column

为探索出性能更为优越的钢木组合柱,对薄壁圆钢筒施加预应力以形成主动围压,并设定预留量制作了预应力薄壁钢约束圆木柱试件,进行了其轴心受压性能试验,明确了其破坏过程和失效模式;整理获得了荷载-位移关系曲线和荷载-应变关系曲线,以及初始刚度、残余承载比和耗能等轴心受压性能指标,进行了轴心受压性能分析。同时,采用ABAQUS有限元软件开展了预应力薄壁钢约束圆木柱轴心受压试验的数值模拟分析,并提出了其轴心受压极限承载力计算公式。结果表明,预应力薄壁钢约束圆木柱受预留量、螺栓间距、薄壁钢厚度和长细比的影响,表现出四种不同破坏模式;考虑木材和钢材弹性模量差异大而设定一定的预留量,并采用合适薄壁钢厚度、螺栓间距和长细比,预应力薄壁钢约束圆木柱具有较好的轴心受压承载力、初始刚度、残余承载力和耗能等优越轴心受压性能。所建立的预应力薄壁钢约束圆木柱轴心受压有限元模型与轴心受压极限承载力计算公式计算结果与试验结果吻合良好,可用于相应的受力计算分析。

To explore the steel⁃wood composite column with more superior performance,the thin⁃walled steel cylinder is prestressed to form the active confining pressure,and the prestressed thin⁃walled steel confined circular timber column specimens are made by setting the reservation amount.The axial compression performance test is carried out,and the failure process and failure mode are clarified.The load⁃displacement relationship curve and load⁃strain relationship curve,as well as the axial compression performance indexes such as initial stiffness,residual bearing ratio and energy dissipation are obtained and the axial compression performance analysis is carried out.At the same time,the finite element software ABAQUS is used to carry out the numerical simulation analysis for the axial compression test of the prestressed thin⁃walled steel confined circular timber column,and the calculation formula of the ultimate bearing capacity of the axial compression is proposed.The results show that the prestressed thin⁃walled steel confined circular timber column is affected by the amount of reservation,bolt spacing,thin⁃walled steel thickness and slenderness ratio,showing four different failure modes.With considering the large difference of the elastic modulus between wood and steel,setting a certain amount of reservation and adopting the appropriate thin⁃walled steel thickness,bolt spacing and slendermess ratio,the prestressed thin⁃walled steel confined circular timber columns have better axial compression bearing capacity,initial stiffness,residual bearing capacity and energy dissipation.The calculated results of the finite element model and the formula of ultimate bearing capacity for the prestressed thin⁃walled steel confined circular timber column under axial compression are in good agreement with the experimental results,which can be used for the corresponding calculation and analysis.