Development of Diagnostic Procedure for Concrete Structures

混凝土结构诊断程序的开发

• 批准号: 06555126
• 负责人: SHIGEISHI Mitsuhiro
• 金额: $ 6.85万
• 依托单位: Kumamoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06555126/
• 关键词: Concrete Structure; Diagnostics; Corrosion of Reinforcement; Deterioration Degree; Ultrasonics; Acoustic Emission; Infrared Thermography

Diagnostic procedure is investigated in order to develop the evaluation and inspection techniques. The techniques to be studied and to be practically applied are associated with crack, delamination, surface damage, corrosion of reinforcement, and structural integrity. For this purpose, acoustic emission (AE) method, ultrasonic testing (UT), infrared thermography, radar, and half-cell potential are newly developed and improved. The evaluation of structural integrity is also studied, including an expert system based on the data base of aging bridges.Results obtained are summarized, as follow :(1) The UT measurement was improved and a new technique based on the spectral information was developed to identify crack depths and surface deterioration.(2) AE application to core tests of concrete is investigated. On the dasis of the rate process analysis of AE generating behaviors in the core sample and the damage mechanics, a quantitative evaluation of damage in the core sample is developed.(3) A moment tensor analysis of AE waveforms was investigated and thus a practical procedure is developed to identify crack location, crack type, and crack orientation.(4) To estimate corrosion of reinforcement, two step inspection is proposed. At the first step, location of reinforcement is determined by employing the radar technique. Then, at the second, corrosion potentials on the reinforcement are estimated from half-cell potentials on the surface, by the charge simulation method analytically.(5) The infrared thermography was studied to estimate temperature distribution on concrete surface. Concerning the corrosion of reinforcement, an inverse solution based on the boundary element method (BEM) is newly developed.

研究诊断程序是为了开发评估和检查技术。要研究和实际应用的技术与裂纹，分层，表面损伤，加固的腐蚀和结构完整性有关。为此，新开发和改进了声发射（AE）方法，超声测试（UT），红外热力计，雷达和半细胞电位。还研究了结构完整性的评估，包括基于衰老桥的数据库的专家系统，总结了所获得的回应，如下：（1）改进了UT测量，并开发了基于光谱信息的新技术，以识别裂纹深度和表面降低。在核心样本中AE产生行为的速率过程分析的DASI上，开发了对核心样品中损伤的定量评估。（3）研究了对AE波形的矩张量分析，因此开发了实用过程，从而制定了一个实用程序，以确定裂纹位置，裂纹方向和裂纹方向和裂纹方向。在第一步，加固的位置是通过采用雷达技术来确定的。然后，在第二个，通过分析的电荷仿真方法，从表面上的半细胞电位估算了钢筋上的腐蚀电位。（5）研究红外热力计，以估计混凝土表面上的温度分布。关于加固的腐蚀，新开发了基于边界元素方法（BEM）的反向解决方案。

项目成果

Y.Sakata & M.Ohtsu: "Crack Evaluation in Concrete Members based on Ultrasonic Spectroscopy" ACI Materials Journal. 92(6). 686-698 (1996)

坂田勇

M.Shigeishi and M.Ohtsu: ""Observation of Mixed-Mode Fracture Mechanics by SiGMA-2D"" Journal of AE. Vol.11, No.4. 57-63 (1994)

M.Shigeishi 和 M.Ohtsu：““SiGMA-2D 混合模式断裂力学观察””AE 杂志。

Y.Sakata & Ohtsu: "Crack Evaluation in Concrete Members based on Ultrasonic Spectroscpy" ACI Materials Journal. 92(6). 686-698 (1996)

坂田勇

A.Ishibashi,M.Ohtsu & K.Matsusuyama: "Concrete Core Testing of Harbor Structures using AE Rate Process Analysis" Proc.Ist US-Japan Sympo.on Advances in NDT. 49-54 (1996)

石桥先生、大津先生

K.Matsuyama, T.Fujiwara, A.Ishibashi and M.Ohtsu: ""Field Application of Acoustic Emission for the Diagnosis of Structural Deterioration of Concrete"" Journal of AE. Vol.11, No.4. 65-73 (1994)

K.Matsuyama、T.Fujiwara、A.Ishibashi 和 M.Ohtsu：“声发射在混凝土结构劣化诊断中的现场应用”，AE 杂志。