Flexural Ductile Behavior of Larger BCR Rectangular Hollow Section Columns

• Main Authors: Shu-Hao Lin, 林書豪
• Other Authors: Cheng-Cheng Chen
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/48888449144913192600

碩士 === 國立臺灣科技大學 === 營建工程系 === 103 === In recent years, the production equipment of rectangular hollow section column substantially to increase, the size of rectangular hollow section column can also be significantly increased and are more economical than box column. Therefore, this can be already used in the high-rise steel buildings. But the cold forming process resulting in decreased ductility of rectangular hollow section column, so the toughness of the rectangular hollow section column should be test by structural testing. Rectangular hollow section column using an internal diaphragm system or an external diaphragm system and box column using the general internal diaphragm system made five beam-column sub-assemblage specimens to test their flexural ductile behavior. Experimental results showed that: (1) The external diaphragm system specimen, column and the corner of an external diaphragm system welds than the internal diaphragm system specimen, column and the upper flange of the beam welds even earlier cracks.(2) Rectangular hollow section column and beams joints, the straight line of rectangular hollow section column welding into the heat should be controlled in less than 40 kJ / cm, a corner of rectangular hollow section column welding into the heat should be controlled in less than 30 kJ / cm.(3) For the internal diaphragm system specimen, corner of diaphragm have notching, behavior of column plate by diaphragm supporting so poor and likely to cause local buckling deformation when the column is subjected to lateral force. The opposite of the external diaphragm system specimen, the column around the external diaphragm covering, column local buckling deformation will occur later.(4) Rectangular hollow section column made of cold-rolled forming, causing its strength than box columns.(5) Surround of box column full welding is easily to crack caused by buckling deformation. The opposite of surround of rectangular hollow section column isn’t to crack caused by buckling deformation.(6) For same column section, the real b/t (width to thickness ratio) of box column is larger than the real b/t of rectangular hollow section column. Therefore, when we choose rectangular hollow section column section, we need to understand the real b/t of rectangular hollow section column calculated and the real b/t of box column in different ways to calculate.