Study on Inspection of Void in Concrete by Impact Test

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K05869
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Dynamics/Control
• Research Institution: Osaka City University
• Principal Investigator: Kawai Tadao 大阪市立大学, 大学院工学研究科, 教授 (20177637)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 打撃試験 / コンクリート構造物 / 浮き / 独立成分分析

Outline of Final Research Achievements

We investigated the method of detecting a void in the concrete structure by the impact test. The shock waves generated by hitting the concrete propagates along a surface and through the inside of a concrete. Sensors placed on several locations apart from the impact point measure both a surface wave and a wave passing through internal concrete. We separated a internal wave from a surface wave by the method of the independent component analysis to detect a void.
At first, we checked the effectiveness of the method by simulation. Then we made a test system. Our system was composed of a impact part and sensor parts. At a impact part, a steel ball was shot by a spring to a concrete surface. At sensor parts, a small block attached an acceleration sensor was pressed to a concrete surface by a heavy mass. By this way, high frequency components of a shock wave were measured. At last, our test equipment showed a good performance to detect a void in a concrete structure.

Free Research Field

診断工学