型钢-钢纤维混凝土局部组合梁受力性能  

Structural behavior of locally composite steel and steel fiber reinforced concrete beams under monotonic loading

作　　者：伍凯[1] 杨毅恒 诸睿哲 张雁杰 梁庆庆 王世龙 WU Kai;YANG Yiheng;ZHU Ruizhe;ZHANG Yanjie;LIANG Qingqing;WANG Shilong(College of Civil and Transportation Engineering,Hohai University,Nanjing 210024,China)

机构地区：[1]河海大学土木与交通学院,南京210024

出　　处：《哈尔滨工业大学学报》2025年第2期153-163,共11页Journal of Harbin Institute of Technology

基　　金：国家自然科学基金(51208175);中央高校基本科研业务费专项(B200202067)。

摘　　要：为解决型钢混凝土结构的施工困难,充分发挥各部分材料的性能优势,将钢筋笼离散化为随机分布的钢纤维,并将钢纤维混凝土集中应用于受压区,形成型钢-钢纤维混凝土局部组合梁。对18根不同钢纤维体积率(ρ_(sf))、剪跨比(λ)、型钢受压翼缘上下部混凝土保护层厚度(C_(ss)、C_(sv))和型钢规格(I_(s))的组合梁试件进行四点弯试验。分析试验参数对破坏模式、荷载-挠度曲线以及破坏对称性的影响。结果表明:增大ρ_(sf)对小剪跨比试件(λ为1.5或1.7)的界面黏结性能具有积极改善作用,试件破坏模式由界面破坏转为弯扭破坏;混凝土保护层厚度须随I_(s)同步增大,确保混凝土保护层对型钢提供足够的“握裹效应”,避免或削弱弯扭变形的不利影响。通过高斯分布拟合,得到试件整体性能开始出现严重退化时的挠度退化系数,进而对构件整体性能开始出现严重退化时的挠度进行预测。To address the construction difficulties of steel reinforced concrete structures and fully leverage material performance,the rebar cage was discretized into randomly distributed steel fibers.Steel fiber reinforced concrete was concentrated in the compression zone to form the locally composite steel and steel fiber reinforced concrete structure.Four-point bending tests were carried out on 18 beam specimens with different steel fiber volume fractions(ρ_(sf)),shear span ratios(λ),concrete protective layer thicknesses for upper and lower parts of steel compression flange(C_(ss) and C_(sv)),and shaped steel specifications(I_(s)).The effects of these test parameters on failure modes,load-deflection curves,and failure symmetry of specimens were analyzed.The results show that increasingρ_(sf) had a positive effect on improving the interface bonding performance for specimens with smallerλ(1.5 or 1.7),and the failure mode changed from interface failure to bending-torsion failure.To ensure that the concrete protective layer provides sufficient"grip-wrap effect"on the shaped steel and avoid or weaken the adverse effects of bending and torsion deformation,C_(ss) and C_(sv) should increase simultaneously with I_(s).The deflection degradation coefficient was obtained by Gaussian distribution fitting,and the deflection when the specimen′s overall performance began to seriously degrade was predicted.

关 键 词：组合结构 型钢混凝土 钢纤维混凝土 破坏模式 荷载-挠度曲线 能量耗散 

分 类 号：TU398[建筑科学—结构工程]