Experimental study on inelastic lateral torsional buckling strength of H-shaped steel beam-columns under high axial force

高轴力作用下H型钢梁柱非弹性侧扭屈曲强度试验研究

基本信息

批准号：
13650638
负责人：
YAMAZAKI Shinji
金额：
$ 1.98万
依托单位：
Tokyo Metropolitan University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13650638/
关键词：
steel structure beam-column buckling test lateral torsional buckling plastic buckling monotonic loading cyclic loading random loading 曲げ捩れ座屈

项目摘要

There is a case in which the energy absorption capacity of H-shaped beam-columns subject to axial forces and double curvature bending moment during severe earthquakes is limited by lateral torsional buckling. Most of past studies concerning the lateral torsional buckling of beam-columns in plastic range have been carried out only for cases where monotonic bending is loaded. However, beam-columns of multi-story frames are subjected to both fluctuating axial forces and cyclic bending moment during earthquakes. The fluctuating axial forces are caused by overturning moment and vertical vibrations. In this study, the maximum strength as well as the energy absorption capacity of beam-columns which is determined by lateral torsional buckling was studied by carrying out experiments under various loading conditions with consideration to the states in which columns are subjected to loads during earthquakes.The loading conditions in the experiments are as follows: (1) Monotonic horizontal loading … More under constant axial force, (2) Cyclic horizontal loading under constant axial force, (3) Cyclic horizontal loading under fluctuating axial force, (4) Random cyclic horizontal loading under random fluctuating axial force.When comparing the skeleton curve obtained from the relationship between the load and the deformation for the specimen subject to the cyclic horizontal load under constant axial force to the load-deformation relationship for the specimen subjected to monotonic horizontal loading under constant axial force, it is discernible that the maximum strength and the deformation at the time of maximum strength of the skeleton curve are smaller than those seen for the monotonic loading. In cases where the ultimate strength is determined by local buckling, it is generally known that the skeleton curve obtained from cyclic experiments nearly coincides with the monotonic loading curve. It was found out that the maximum strength is affected by plastic hysteresis when the strength is limited by lateral torsional buckling unlike the case in which the strength is determined by local buckling. This is so because in the case of the plastic lateral torsional buckling the buckling deformation progresses not only due to the increase in internal force as well as the extension of plastic regions but also due to the accumulation of plastic deformation caused by the cyclic bending about a strong axis. The effects of the fluctuating axial force and the plastic bending hysteresis upon the buckling strength and energy absorption capacity were clarified. Less

在某种情况下，在严重的地震中受到轴向力和双重曲率弯矩的H形梁柱的吸收能力受到横向扭转屈曲的限制。过去的大多数研究涉及塑料范围内的光束柱的侧向扭转屈曲，仅在装载单调弯曲的情况下进行。但是，多层框架的梁柱受到地震期间的波动轴向力和循环弯矩的影响。波动的轴向力是由推翻力矩和垂直振动引起的。在这项研究中，通过在各种载荷条件下进行实验，考虑到柱子在地震期间承受负载的状态，通过在各种载荷条件下进行实验来确定的最大强度以及梁柱的能量吸收能力。力，（3）在波动的轴向力下的环状水平载荷，（4）在随机波动轴向力下随机循环水平载荷，当比较从负载和样品之间的变形和恒定轴向载荷载荷载荷载荷量的恒定量载荷载荷载荷量的骨架曲线进行比较时，将骨骼曲线从可以发现，骨骼曲线最大强度时的最大强度和变形小于单调载荷的最大强度和变形。如果最终强度由局部屈曲确定，通常知道从循环实验获得的骨骼曲线几乎与单调载荷曲线一致。发现当强度受到侧向扭转屈曲的限制时，最大强度会受到塑性滞后的影响，与局部屈曲确定强度的情况不同。之所以如此，是因为在塑料侧向扭转屈曲的情况下，屈曲变形不仅是由于内力增加以及塑料区域的延伸而进行的，而且还因为围绕强轴的循环弯曲引起的塑性变形的积累。阐明了波动轴向力和塑料弯曲磁滞对屈曲强度和能量吸收能力的影响。较少的