箍筋约束混凝土结构及其发展展望

Development and prospects of hoop reinforcement confined concrete

通过外部约束,限制混凝土的横向变形,可以有效地改善核心混凝土自身原有受压特性,大大增强混凝土的抗压强度和变形能力。根据约束材料和约束形式的不同,约束混凝土包括箍筋约束混凝土,钢管约束混凝土,FRP约束混凝土及更多新材料、新工艺约束混凝土等。对箍筋约束混凝土的发展历史、研究现状和发展趋势进行了较全面的综述,分析了各类箍筋约束混凝土的约束机制,介绍了国内外常见的箍筋约束混凝土的本构模型。针对约束混凝土的性能与约束水平有直接关系,提出将箍筋的强度提高,直径变细,间距变密,使得箍筋能对混凝土起到更有效的约束。此外,还介绍了区域约束混凝土和五螺箍约束混凝土的约束机制和受力性能。

With external confinement,the transverse deformation of concrete is restricted,thus thre compressive behaviour of core concrete is improved.According to confining materials and confining models,confined concrete is classified into stirrup confined concrete,steel tube confined concrete,FRP confined concrete and other new material confined concrete The development of hoop reinforcement confined concrete structures are reviewed.Research works on mechanical properties,confined mechanism and common constitutive models of hoop reinforcement confined concrete are summarized.As the restriction level is directly related to the properties of confined concrete,it is suggested that the transverse reinforcement strength should be enhanced,the diameter of tube should be thinned,and the spacing should be reduced.It is recommended that high-strength concrete members be confined with high-strength transverse reinforcements to improve the capacity and deformation performance.Furthermore,the restriction mechanism and mechanical properties of regional confined concrete and 5-spirals confined concrete are introduced.