Development of hybrid fiber reinforcements of enhancing structures with integrated performances

开发具有综合性能的增强结构的混合纤维增强材料

基本信息

批准号：
17360201
负责人：
WU Zhishen
金额：
$ 9.54万
依托单位：
Ibaraki University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2005
资助国家：
日本
起止时间：
2005 至 2006
项目状态：
已结题

项目摘要

In this study, first, a comprehensive design concept of hybrid fiber reinforced polymers (FRP) composites with several types of fibers with different specific properties is proposed in order to realize different required performances including tensile strength, stiffness, ductility, creep and fatigue resistances and cost performance as one of the most important indices. Then the material behavior including the long-term performances such as creep and fatigue is experimentally investigated. Quantitative indices to evaluate and control stress or load drops during the gradual fractures of different fibers are proposed and their effectiveness are experimentally verified. The usefulness of adopting continuous fibers with higher energy absorption capacity is also verified.For the application of hybrid fiber sheets in strengthening RC concrete structures, it is found that the use of high modulus carbon fibers in hybrid systems could increase the serviceability such as yielding load. Moreover, … More it is conformed that structures can be strengthened with appropriately designed hybrid fiber reinforcements of consisting of three type of continuous fibers with different specific properties to meet with the overall requirements of structural performances. The debonding failure of hybrid FRP sheets can be also avoided through an appropriate hybrid design. On the other hand, a novel type of FRP-RC hybrid structures as one of new constructions with integrated structural performances is proposed.Then, the flexural or diagonal macro-crack induced debonding failure mechanisms in FRP-strengthened concrete structures are investigated numerically based on nonlinear FEM and fracture mechanics. Moreover, the modeling of long-term behavior such as creep and fatigue of FRP-concrete interface is developed.Finally, a self-sensing manner of FRP-strengthened or FRP-RC hybrid structures is proposed through developing hybrid carbon fiber sensors. Besides, a health monitoring system based on distributed fiber optic sensing techniques is developed to monitor the strengthening effects and other structural performances of FRP-strengthened structures. Less

在这项研究中，首先，为了实现不同的性能，僵硬，蠕变和疲劳姿态，并作为重要的指数之一，以实现不同的性能。提出了疲劳的iSperimen tally tally tally，并在实验中验证了不同纤维的逐渐骨折。 rc混凝土结构ncrease的载荷量。在FRP加长的混凝土中，基于非线性FEM和裂缝机制，研究了FRP加长的混凝土中的屈曲或对角线宏观裂缝诱导的脱键失败机制，例如蠕变和诸如FRP - 凝结界面的疲劳等长期行为。最后，通过开发的杂交碳纤维传感器的植入型FRP强度或FRP-RC杂种的自感应方式。