摘要
使用超高韧性水泥基复合材料(Ultra High Toughness Cementitious Composite,简称UHTCC)取代普通混凝土可以有效控制裂缝宽度,阻止外界不利因素进入混凝土和钢筋,极大降低钢筋腐蚀的可能性,从而可以显著提高钢筋混凝土结构耐久性。UHTCC是在单轴拉伸状态下具有应变硬化特性的超高韧性材料,能够稳定地分担部分拉力。为了对钢筋增强超高韧性水泥基复合材料受弯结构构件进行更加合理的设计以节约钢材,在设计中应该考虑受拉区UHTCC拉伸承载能力。开展了钢筋增强超高韧性水泥基复合材料受弯构件的研究工作,先后完成了受弯理论分析、无腹筋长梁实验研究、试验研究与理论分析验证对比、裂缝控制分析、承载力简化计算方法等方面研究。该文依据UHTCC单轴拉伸状态下的应变硬化特性、单轴压缩状态的双直线模型以及平截面假定,进行了钢筋增强超高韧性水泥基复合材料受弯构件的理论分析,包括正截面受弯各阶段内力分析、界限配筋梁受压区高度的确定、加载至破坏整个过程的弯矩-曲率关系的确定以及跨中挠度的计算。
The injurant such as vapor, carbon dioxide, chloride may lead the corrosion of steel bar if there is any macro-crack in concrete structures. The possibility of corrosion should be evidently reduced in respect that ultra high toughness cementitious composite （UHTCC） can effectively control crack width, so that the durability will be improved markedly, compared to reinforced concrete structures. UHTCC shows high toughness and pseudo strain-hardening behavior under tension. Therefore, it can undertake a part of the tension load. In order to logically design the reinforced UHTCC members under bending load and saving steel products, the tension load carrying capacity of UHTCC in tension region should be considered. The investigations on reinforced UHTCC flexural members have been carried out, including theoretical analysis of bending members, experimental research on long beams without web reinforcement, validation and comparison between experimental and theoretical results, the analysis of crack control and simplified calculation methods of load bearing capacity. According to pseudo strain-hardening behavior of UHTCC under tension, a bilinear model under compression and plane-section assumption, the paper presents the theoretical analysis on reinforced UHTCC flexural members, such as the analysis of the internal force at different stage, confirmation of height of compression zone, the moment-curvature relationship and calculation of mid-span deflection.
出处
《工程力学》
EI
CSCD
北大核心
2010年第7期92-102,共11页
Engineering Mechanics
基金
国家自然科学基金重点项目(50438010)
南水北调工程建设重大关键技术研究及应用项目(JGZXJJ2006-13)
