Evaluation Methods of Mechanical Performance of RC members Application of Non-destructive Testing to Evaluation of Mechanical Performance of RC Beams with Corroded Reinforcing Bars by salt damage

钢筋混凝土梁力学性能评价方法无损检测在盐害腐蚀钢筋混凝土梁力学性能评价中的应用

• 批准号: 18360207
• 负责人: KAMADA Toshiro
• 金额: $ 5.52万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 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-18360207/
• 关键词: Reinforced Concrete; Salt damage; Nondestructive test; FEM analysis; Ultimate Strength; Deterioration condition; Electro-Chemical Methods; Bonding; 電気化学的方法; 超音波法; 耐力; 自然電位; 超音波伝播速度

Generally, concrete inspections are applied to determine the current strength and durability of a structure. However it is difficult to determine the strength and performance of a structure from inspection results, therefore currently indirect estimation from visual observation of cracks, corrosion levels from nondestructive test among others are used. Therefore, developing a method to directly determine the current conditions of a structure in a standardized manner will enhance rationalization of management of structures.In this study, first, various non-destructive tests (Ultrasonic Methods, Half Cell Potential Methods and Polarization Resistance Methods) were performed on reinforced concrete beams whose reinforcing bars have been corroded through electricity. The specimen was a rein-forced concrete beam of width 230 mm, height 230 mm and length 1500 mm with the tensile side having 3 reinforcing bar at a 75 mm span. The rebar cover was 33 mm from the sides and bottom of the specimen. … More Corrosion enhancement experiment was conducted to rebar. The specimen was placed on top of a metallic plate sat at the bottom of a stainless steel container full with 3% saline solution. A circuit was made with the metallic plate as the cathode and the rebar protruding from the specimen as the anode and 1Amp direct current fed into the circuit. Two periods of current flow, 14 days and 28 days were set in order to have specimens with varying levels of corrosion. Second, damage maps were made which reflect the results of nondestructive tests. The results were then input into finite element method (FEM) analysis and the mechanical performance of the test specimens investigated. Last, the adequacy of the FEM analysis results were confirmed by carrying out flexural loading tests on the rein-forced concrete beams whom reinforcing bar have been corroded.The following conclusions were obtained in this study.1. It was possible to grasp the extent of deterioration in a corroded reinforced concrete beam from deterioration maps estimated by results of various nondestructive test methods. Furthermore, the use of FEM analysis as an effective method in evaluation of structures' mechanical performance was confirmed.2. It was possible to use FEM analysis utilizing results from nondestructive test, to simulate on the whole the crack properties and load-displacement response of reinforced concrete beams with corroded rebar. However, FEM analysis was unable to simulate loading tests with peculiar failure modes. From the above, it is of the view that the importance to replicate cracks on the concrete surface caused by corrosion, in the analysis model has been made clear. Less

一般来说，混凝土检查是用来确定结构的当前强度和耐久性。然而，很难从检查结果中确定结构的强度和性能，因此目前使用的是通过肉眼观察裂缝来间接估计，以及通过无损检测来腐蚀水平等。因此，开发一种以标准化的方式直接确定结构现状的方法，将增强结构管理的合理化。本研究首先对钢筋经电腐蚀的钢筋混凝土梁进行了各种无损检测（超声法、半电池电位法和极化电阻法）。试件为宽230 mm、高230 mm、长1500 mm的钢筋混凝土梁，受拉侧有3根钢筋，跨度为75 mm。钢筋盖距试件两侧和底部33毫米。对螺纹钢进行了进一步的增腐蚀试验。标本被放置在金属板的顶部，金属板位于一个装满3%生理盐水溶液的不锈钢容器的底部。以金属板为阴极，从试样中伸出的钢筋为阳极，将1安培的直流电输入电路。为了使试件具有不同程度的腐蚀，设置了14天和28天两个时间段的电流。其次，绘制了反映无损检测结果的损伤图。然后将结果输入到有限元分析中，并对试件的力学性能进行了研究。最后，通过对钢筋锈蚀的钢筋混凝土梁进行受弯荷载试验，验证了有限元分析结果的充分性。本研究得到以下结论：1。利用各种无损检测方法的结果，从腐蚀图中估计钢筋混凝土梁的腐蚀程度是可能的。进一步验证了有限元分析是评价结构力学性能的有效方法。利用无损检测结果进行有限元分析，可以从整体上模拟含腐蚀钢筋的钢筋混凝土梁的裂缝特性和荷载-位移响应。然而，有限元分析无法模拟具有特殊破坏模式的加载试验。由此可见，在分析模型中，在混凝土表面复制腐蚀引起的裂缝的重要性已得到明确。少

项目成果

腐食による鉄筋とコンクリートとの界面評価における各種非破壊試験の適用範囲

各种无损检测评价钢筋与混凝土界面腐蚀情况的适用范围

• 发表时间: 2008
• 期刊: 土木学会第63回年次学術講演会講演概要集
• 作者: 前 裕史;鎌田敏郎;峯澤博行;内田慎哉;稲熊唯史
• 通讯作者: 稲熊唯史

Evaluation of Bonding Condition between Rebar and Concrete due to Rebar Corrosion by NDT

钢筋腐蚀引起的钢筋与混凝土粘结状况的无损检测评价

• 发表时间: 2008
• 作者: Shinya;UCHIDA;Toshiro;RAMADA;Hiroyuki;MINEZAWA;Hirofumi;MAE
• 通讯作者: MAE

非破壊試験による鉄筋-コンクリート界面の評価手法

钢筋-混凝土界面无损检测评价方法

• 发表时间: 2008
• 期刊: コンクリート工学年次論文集 30(掲載決定)
• 作者: 前 裕史;鎌田敏郎;峯澤博行;内田慎哉
• 通讯作者: 内田慎哉

Application of Non-destructive Testing to Evaluation of Mechanical Performance of RC Beams with Corroded Reinforcing Bars

无损检测在钢筋锈蚀钢筋混凝土梁力学性能评价中的应用

• 发表时间: 2007
• 期刊: Proceedings of the Concrete Structure Scenarios Vol.8
• 作者: Hiroyuki;MINEZAWA;Toshiro;KAMADA;Shinichi;MIYAZATO;Ichira;KURODA;Hiroshi;ONISHI;Shinya;UCHIDA
• 通讯作者: UCHIDA

Effects of unsteady air temperature for the Evaluation of Corrosion Velocity of rebar in mortar

不稳定空气温度对砂浆中钢筋腐蚀速度评价的影响

• 发表时间: 2007
• 作者: Tunehiko;MITAMURA;Shinichi;MIYAZATO;Yoichi;HIRAISHI
• 通讯作者: HIRAISHI