权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Utilization of fiber reinforced concrete to control crack width of reinforced concrete structures

利用纤维混凝土控制钢筋混凝土结构的裂缝宽度

基本信息

批准号：
18560450
负责人：
UCHIDA Yuichi
金额：
$ 1.64万
依托单位：
Gifu University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2006
资助国家：
日本
起止时间：
2006 至 2007
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18560450/
关键词：
concrete fiber reinforced concrete crack bond finite element analysis 有限要素解析

项目摘要

1. Crack behavior of reinforced concrete beams using various types of fiber reinforced concrete (ordinarily steel fiber reinforced concrete and two types of high performance fiber reinforced cement composites with multiple fine cracks (HPFRCC)) was investigated through the flexural loading tests. The crack width was decreased by using the fiber reinforced concrete in the tensile region of the beam. The crack width of the beams using HPFRCC was little than 0.1mm even at yield loading level. However, the crack distribution of the beams was influenced by material properties of HPFRCC.2. The tensile tests of uniaxial reinforded concrete specimens were carried out to clarify the influence of fiber reinforced concrete on the crack width and bond property between the concrete and the steel bar. There were little differences between bond property of the plain concrete and that of the fiber reinforced concrete.The reducing effect of crack width by using fiber reinforced concrete was caused by the bridging effect of the fiber at the crack surface. The bridging effect of the fiber was evaluated by the tension softening curve of the fiber reinforced concrete.3. The finite element analysis on the uniaxial reinforced concrete specimen and the pull out specimen were carried out to clarify the mechanism of the bond behavior. The combination of the very fine mesh model and the compression softening model for the concrete material property caused the compressive strain localization at the front of the rib surface of the deformed steel bar. The bond slip at the high stress level could not be simulated due to the strain localization. The macroscopic bond model was proposed to overcome the problem of the strain localization. The bond slip was represented by the shear deformation of the bond damaged layer around the steel bar in the proposed model.

1.通过弯曲加载试验，研究了不同类型纤维混凝土（普通钢纤维混凝土和两种高性能多细裂纹纤维增强水泥基复合材料（HPFRCC））加固混凝土梁的开裂性能。在梁的受拉区采用纤维混凝土，可以减小裂缝宽度。在屈服荷载水平下，HPFRCC梁的裂缝宽度小于0.1mm。然而，梁的裂缝分布受材料性能的影响.通过单轴拉伸试验，研究了纤维混凝土对混凝土裂缝宽度和钢筋与混凝土粘结性能的影响。纤维混凝土与素混凝土的粘结性能差异不大，纤维混凝土的裂缝宽度减小作用主要是由于纤维在裂缝表面的桥接作用。通过纤维混凝土的拉伸软化曲线评价了纤维的桥接作用.通过对单轴钢筋混凝土试件和拔出试件的有限元分析，阐明了粘结性能的机理。细网格模型与混凝土材料特性的压缩软化模型相结合，导致了变形钢筋肋面前端的压缩应变局部化。高应力水平下的粘结滑移由于应变局部化而无法模拟。为了克服应变局部化问题，提出了宏观粘结模型。在该模型中，钢筋粘结滑移用钢筋周围粘结损伤层的剪切变形来表示。