采用屈曲约束纵筋的钢筋混凝土短柱轴压性能试验研究
|
摘要
中、高烈度区钢筋混凝土结构的抗地震倒塌性能,近年来成为国内外学术界关注的问题之一。由于地震作用下结构发生倒塌破坏的成因与机制非常复杂,仅仅通过概念设计难以满足日益多样化和复杂化的工程结构对抗倒塌性能的需求。针对纵向钢筋发生屈曲失稳破坏后框架柱丧失竖向承载力、结构竖向传力路径中断可能导致的局部倒塌或者连续倒塌,提出屈曲约束纵筋技术,对考虑了多个设计参数的一组屈曲约束钢筋试件以及4根钢筋混凝土短柱进行轴压试验,初步检验屈曲约束套管在防止钢筋受到高轴压力时发生屈曲失稳的有效性,比较不同箍筋用量和屈曲约束套管布置方式对短柱轴压性能的影响。试验结果表明,屈曲约束钢筋受压时能表现出与受拉时大体相同的力学特性,屈曲约束套管能有效防止钢筋混凝土柱在混凝土保护层严重开裂和剥落后发生纵筋屈曲失稳破坏,避免柱突然失去轴向承载力。
The seismic collapse safety of RC structures in medium to high seismic regions has attracted the attention of researchers in recent years. Since the seismic collapse is a very complicated process with implicit causes and mechanisms,the conceptual design method alone can not satisfy the collapse prevention requirements of engineering structures that have become increasingly diversified and complicated. In this paper,the buckling restrained rebar is proposed for the prevention of collapse caused by loss of vertical load carrying capacity of RC columns due to the buckling failure of longitudinal rebars and the cutoff of the vertical load path. Two sets of tests were carried out for steel coupons and stub columns under axial loading with consideration of various parameters. Test results indicate that the buckling restrained rebar can behave almost the same under compression and tension. The buckling restraining device can effectively prevent the buckling of longitudinal rebars under high axial load level when the cover concrete has severely cracked and spalled off and the sudden loss of axial load carrying capacity of the column can be avoided.
The seismic collapse safety of RC structures in medium to high seismic regions has attracted the attention of researchers in recent years. Since the seismic collapse is a very complicated process with implicit causes and mechanisms,the conceptual design method alone can not satisfy the collapse prevention requirements of engineering structures that have become increasingly diversified and complicated. In this paper,the buckling restrained rebar is proposed for the prevention of collapse caused by loss of vertical load carrying capacity of RC columns due to the buckling failure of longitudinal rebars and the cutoff of the vertical load path. Two sets of tests were carried out for steel coupons and stub columns under axial loading with consideration of various parameters. Test results indicate that the buckling restrained rebar can behave almost the same under compression and tension. The buckling restraining device can effectively prevent the buckling of longitudinal rebars under high axial load level when the cover concrete has severely cracked and spalled off and the sudden loss of axial load carrying capacity of the column can be avoided.
引文
[1]GB 50011—2010建筑抗震设计规范[S].北京:中国建筑工业出版社,2010(GB 50011—2010 Code for seismic design of buildings[S].Beijing:China Architecture&Building Press,2010(in Chinese))
[2]叶列平,曲哲,马千里.从汶川地震框架结构震害谈“强柱弱梁”屈服机制的实现[J].土木工程学报,2008,38(11):52-67(Ye Lieping,Qu Zhe,Ma Qianli.Study on ensuring the strong column-weak beam mechanism for RC frames based on the damage analysis in the Wenchuan eathquake[J].China Civil Engineering Journal,2008,38(11):52-67(in Chinese))
[3]Haselton C B,Liel A B,Deierlein G G.Seismic collapse safety of reinforced concrete buildings.I:assessment of ductile moment frames[J].Journal of Structural Engineering,2011,137(4):481-491
[4]ASCE 7—2002.Minimum design loads for buildings and other structures[S].Reston,VA,2002
[5]ACI 318—2005.Building code requirements for structural concrete and commentary[S].Farmington Hills,MI,2005
[6]潘毅,曹双寅,林拥军.负载下碳纤维布约束混凝土方柱的轴压试验研究[J].四川大学学报:工程科学版,2010,42(6):56-60(Pan Yi,Cao Shuangyin,Lin Yongjun.Experimental research on axially loaded squaresection concrete columns confined by carbon fiber reinforced plastic(CFRP)under preload[J].Journal of Sichuan University:Engineering Science Edition,2010,42(6):56-60(in Chinese))
[2]叶列平,曲哲,马千里.从汶川地震框架结构震害谈“强柱弱梁”屈服机制的实现[J].土木工程学报,2008,38(11):52-67(Ye Lieping,Qu Zhe,Ma Qianli.Study on ensuring the strong column-weak beam mechanism for RC frames based on the damage analysis in the Wenchuan eathquake[J].China Civil Engineering Journal,2008,38(11):52-67(in Chinese))
[3]Haselton C B,Liel A B,Deierlein G G.Seismic collapse safety of reinforced concrete buildings.I:assessment of ductile moment frames[J].Journal of Structural Engineering,2011,137(4):481-491
[4]ASCE 7—2002.Minimum design loads for buildings and other structures[S].Reston,VA,2002
[5]ACI 318—2005.Building code requirements for structural concrete and commentary[S].Farmington Hills,MI,2005
[6]潘毅,曹双寅,林拥军.负载下碳纤维布约束混凝土方柱的轴压试验研究[J].四川大学学报:工程科学版,2010,42(6):56-60(Pan Yi,Cao Shuangyin,Lin Yongjun.Experimental research on axially loaded squaresection concrete columns confined by carbon fiber reinforced plastic(CFRP)under preload[J].Journal of Sichuan University:Engineering Science Edition,2010,42(6):56-60(in Chinese))
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心