箍筋间距对型钢混凝土结构轴压性能影响研究  

Study on the Influence of Stirrup Spacing on Axial Compression Performance of Steel Reinforced Concrete Structure

作　　者：路军富[1] 苗志豪 王明胜 汤印 LU Junfu;MIAO Zhihao;WANG Mingsheng;TANG Yin(State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu,Sichuan 610059,China;China Railway City Development and Investment Group Co.Ltd,Chengdu,Sichuan 610000,China;China Railway Eryuan Engineering Group Co.Ltd,Chengdu,Sichuan 610031,China)

机构地区：[1]地质灾害防治与地质环境保护国家重点实验室(成都理工大学),成都610059 [2]中铁城市发展投资集团有限公司,成都610000 [3]中铁二院工程集团有限责任公司,成都610031

出　　处：《铁道工程学报》2025年第1期83-88,100,共7页Journal of Railway Engineering Society

基　　金：国家自然科学基金面上项目(51978088);中铁二院科技开发项目(KSNQ213025);SKLGP国家重点实验室自主课题(SKLGP2021Z007)。

摘　　要：研究目的:隧道穿越断层、软弱破碎带等不良地质时易导致初期支护型钢与喷射混凝土接触界面出现相对滑移现象,使得初期支护结构承载能力降低、极易失稳。为提升型钢与喷射混凝土支护协同承载能力与变形延性,提出一种沿型钢翼缘表面环向布置箍筋的结构形式,为探明箍筋间距对型钢及混凝土的约束作用,开展4种不同工况的型钢混凝土柱轴心受压试验和数值分析,揭示箍筋间距对型钢喷射混凝土柱的轴压承载能力的影响规律。研究结论:(1)无箍筋约束工况下,工字型钢与喷射混凝土接触界面极易发生分离破坏,二者无法协同承载,当设置环向箍筋约束时,型钢混凝土试件破坏模式为胀裂破坏,其环向箍筋对型钢翼缘和混凝土变形约束效果较好,从而增强了型钢混凝土试件的极限承载力和延性;(2)环向箍筋约束试件的极限承载力随箍筋间距的减小而增大,相较于无箍筋约束试件,环向箍筋间距为150 mm、100 mm、50 mm试件的极限承载力的增长百分比分别为18.78%、24.59%和31.16%;(3)减小环向箍筋间距对型钢混凝土柱的极限承载能力有较大提升,当布置箍筋间距75 mm时约束效果最优;(4)本研究成果可为隧道支护结构抗变形设计提供参考和借鉴。Research purposes:When the tunnel passes through bad geology such as faults and weak fracture zones,it is easy to cause the relative slip phenomenon of the contact interface between the initial support steel and the shotcrete,which makes the bearing capacity of the initial support structure reduce and easily destabilize.To improve the cooperative bearing capacity and deformation ductility of steel and shotcrete support,a structural form of stirrups arranged circumferentially along the surface of the steel flange was proposed.To explore the restraint effect of stirrup spacing on steel and concrete,axial compression tests and numerical analysis of steel-reinforced concrete columns under four different working conditions were carried out to reveal the influence of stirrup spacing on the axial compression bearing capacity of steel-reinforced shotcrete columns.Research conclusions:(1)Under the condition of no stirrup constraint,the contact interface between I-shaped steel and shotcrete is prone to separation failure,and the two cannot bear the load together.When the circumferential stirrup constraint is set,the failure mode of the steel-reinforced concrete specimen is the expansion crack failure.The circumferential stirrup has a good constraint effect on the deformation of the steel flange and the concrete,thus enhancing the ultimate bearing capacity and ductility of the steel-reinforced concrete specimen.(2)The ultimate bearing capacity of the specimens with circumferential stirrups increases with the decrease of stirrup spacing.Compared with the specimens without stirrups,the ultimate bearing capacity of the specimens with the circumferential stirrup spacing of 150 mm,100 mm,and 50 mm increases by 18.78%,24.59%,and 31.16%,respectively.(3)The ultimate bearing capacity of steel-reinforced concrete columns is greatly improved by reducing the spacing of circumferential stirrups.When the spacing of hoop stirrups is 75 mm,the constraint effect is the best.(4)The research results can provide reference for the deformation r

关 键 词：环向箍筋间距 型钢混凝土结构 轴压性能 承载能力 

分 类 号：U45[建筑科学—桥梁与隧道工程]