摘要
为了研究喷涂式轻质砂浆-冷弯薄壁型钢墙体立柱的轴压性能,文章采用有限元分析和真实试验对比测试了立柱间距、立柱壁厚、截面尺寸、钢材强度等级、两侧砂浆厚度、横撑数量、立柱长度等参数对立柱轴压承载力的影响;结合新型墙体立柱的试验特征,构建基于弹性稳定理论的力学模型,采用能量法和变分原理求解新型墙体立柱弹性屈曲荷载,进一步求解极限屈曲应力修正参数,得到新型墙体立柱轴压承载力的计算方法.结果表明:有限元分析的极限荷载、破坏模式、荷载位移曲线与试验结果较为接近;新型墙体立柱轴压承载力受两侧砂浆厚度、立柱间距影响不大,但随立柱高度增大而减小,横撑个数对纯龙骨立柱轴压承载力影响较大,而对新型墙体立柱影响较小;新型墙体立柱轴压承载力计算时,采用中国规范修正弹性屈曲应力并计算有效面积求得的极限荷载值小于试验值,建议按照中国规范计算的轴压承载力可乘以1.25的修正系数.
Abstract
To investigate the axial compressive performance of sprayed lightweight mortar-cold-formed thin-walled steel wall columns,this paper employs finite element analysis and experimental testing to examine the effects of parameters such as column spacing,column wall thickness,cross-section dimensions,steel strength grade,thickness of mortar on both sides,number of transverse braces,and length of column on the axial compressive bearing capacity of the columns,respectively.Based on the experimental characteristics of the new wall column,the mechanical model grounded in elastic stability theory is constructed.Using the energy method and variational principle,the elastic buckling load of the new wall column,and the ultimate buckling stress correction parameters are further solved,so as to establish the design and calculation method of the type wall column.The results indicate that the ultimate load,damage mode,load displacement curve of finite element analysis closely align with the experimental findings.The axial compressive load capacity of the new wall column remains largely unaffected by the mortar thickness on both sides and the spacing between columns.In structural design,enhancing the wall thickness of the steel columns,increasing the section size,and improving the steel section's strength can significantly boost the column's axial compressive load capacity.Conversely,as the height of the columns increases,their axial compressive load capacity decreases.While the number of cross braces greatly influences the axial compressive load capacity of pure keel columns,it has a less impact on the new wall columns.When calculating the axial compressive load capacity calculations of new wall columns,using the Chinese norms to correct the elastic buckling stress and compute the effective area yields ultimate load values that are more conservative than the experimental results.It is recommended to multiply the axial compressive capacity by a correction factor of 1.25,which is calculated according to Chinese norms.
维普
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