A Study on Design Method for strengthening of Existing Concrete Structures using Advanced Reinforcing Materials

先进增强材料加固既有混凝土结构的设计方法研究

• 批准号: 08305012
• 负责人: UEDA Tamon
• 金额: $ 6.02万
• 依托单位: HOKKAIDO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08305012/
• 关键词: Strengthening; FRP Sheet; FRP tendon; Deformation of concrete members; Capacity of concrete members; 外ケーブル

This study is carried out to develop the design method for strengthening of exsisting concrete structures using FRP sheets and FRP tendons. Results in this study are summarized on the following three points ; (1)Long term properties of reinforcing materials, (2)Ultimate capacity and deformation of concrete members retrofitted with FRP sheet, (3)Ultimate capacity and deformation of concrete structures retrofitted with FRP tendons.(1) Long-term Properties of Reinforcing Materials・The relaxation ratio represents the natural characteristics of each FRP tendon and varies in proportion to the logarithm of time throughout the entire loading time range.・The tensile strength and bond strength of FRP sheet were not reduced even after FRP sheet is soaked in 10% sulfuric acid solution for six months.(2) Ultimate Capacity of Deformation of Concrete Members Retrofitted with FRP Sheets・It was clarified how concrete strength, and stiffness of FRP sheets affect the bond mechanism of FRP sheet. The bond strength equation was proposed.・When peeling of FRP sheet which is attached to a lower face in a beam as flexural reinforcement does not occur, the bending capacity and deformation of the beam can be predicted by the layr-by-layr procedure.・For failure mode with peeling of FRP sheet along a shear crack, the model of predicting the shear reinforcing effect of FRP sheet was proposed.(3) Ultimate Capacity and Deformation of Concrete Structures Retrofitted with FRP Tendons・The flexural behavior of externally prestressed beams can be estimated by a precise calculation method considering the compatibility of deformations and changes in location of cables.・The ultimate strength of FRP tendons at deviators becomes less then the uniaxial tensile strength. The rate of reduction differs for different type of FRP tendons.・When a cable tensile force was within the range of 40 to 50% of the nominal breaking load for AF rope, failure did not occur during the the 2,000,000-cycle loading.

本研究旨在提出用FRP布和FRP筋加固既有混凝土结构的设计方法。(1)加固材料的长期性能，(2)FRP加固混凝土构件的极限承载力和变形，(3)FRP筋加固混凝土结构的极限承载力和变形。(1)加固材料的长期性能·松弛比代表了每根FRP筋的自然特性，在整个加载时间范围内与时间的对数成比例变化。FRP片材在10%硫酸溶液中浸泡6个月后，其抗拉强度和粘结强度仍未降低。(2)FRP片材加固混凝土构件的极限变形能力·阐明了FRP片材的混凝土强度和刚度对FRP片材粘结机理的影响。提出了粘结强度方程。当粘贴在梁的下表面上的FRP板不发生剥离时，梁的受弯承载力和变形可以通过逐层程序进行预测。(3)FRP筋加固混凝土结构的极限承载力和变形。考虑变形和拉索位置变化的精确计算方法，可以估算体外预应力梁的受弯性能。·FRP筋在斜交处的极限强度小于单轴抗拉强度。不同类型的FRP筋的折减率不同。·当拉索张力在AF绳标称断裂载荷的40%至50%的范围内时，在2,000,000次循环加载期间没有发生破坏。

项目成果

谷口 裕史: "ロープ系連続繊維補強材を外ケーブル緊張材に用いたPC部材の曲げ性状に関する研究" 土木学会論文集. NO. 544/V-32. 167-175 (1996)

Hiroshi Taniguchi：“使用绳基连续纤维增强材料作为外索张力材料的 PC 构件的弯曲性能的研究”，日本土木工程师学会学报，第 544/V-32 号（1996 年）。

岳尾 弘洋: "CFRP接着工法における炭素繊維シートの付着特性" コンクリート工学年次論文報告集. 19・2. 1599-1604 (1997)

Hirohiro Takeo：“CFRP粘合法中碳纤维片材的粘合特性”混凝土工程年论文集19・2 1599-1604（1997）。

Kouyou, Takeo: "Adhesive Characteristic of Carbon Fiber Sheet on CFRP Adhesive Method" Proc. of the Japan Concrete Institute. Vo.19, No.2. 1599-1604 (1997)

Kouyou，Takeo：“碳纤维片材在CFRP粘合方法上的粘合特性”Proc。

Yoshihiro, Takahashi: "Flexural Capacity and Deformation of Reinforced Concrete Beams with Carbon Fiber Sheet" Proc. of the Japan Concrete Institute. Vo.19, No.2. 1611-1616 (1997)

Yoshihiro, Takahashi：“碳纤维板钢筋混凝土梁的弯曲能力和变形”Proc。

Toshiya Maeda: "A Study on Bond Mechanism of Carbon Fiber Sheet" Proceedings of the Third International Symposium on Non-Metallic Reinforcement for Concrete Structures. Vol.1. 279-286 (1997)

Toshiya Maeda：《碳纤维片材粘结机理研究》第三届国际混凝土结构非金属加固研讨会论文集。