scholarly journals Diagnostics of Reinforcement Conditions in Concrete Structures by GPR, Impact-Echo Method and Metal Magnetic Memory Method

2021 ◽  
Vol 13 (5) ◽  
pp. 952
Author(s):  
Karel Pospisil ◽  
Monika Manychova ◽  
Josef Stryk ◽  
Marta Korenska ◽  
Radek Matula ◽  
...  

It is important to use adequately reliable non-destructive methods that would be capable of determining the reinforcement conditions in concrete structures. Three different methods: ground penetrating radar, impact-echo method, and metal magnetic memory method were used for testing laboratory-prepared reinforced concrete beams (with a reinforcing bar of the same diameter along its whole length, reinforcing bar locally impaired, and reinforcing bar interrupted). The ground-penetrating radar proved the correlation of signal parameters with the reinforcing bar condition. An impairment/interruption reinforcing bar appeared in the record from measurements in the transversal and longitudinal direction by changes of the observed depth of the reinforcing bar from the concrete surface and direct wave attenuation. The impact-echo method proved that the shifts of the dominant frequencies from the response signal correspond with the impairment/interruption of the reinforcing bar. Results of diagnostics by the metal magnetic memory method were presented by a magnetogram of the magnetic field strength and field gradient on the measured distance. The changes in the magnetic field strength proved different stress concentration zones due to the reinforcing bar condition. The used non-destructive methods showed that they are capable of indicating the different reinforcement conditions in reinforced concrete beams. This paper indicates in which cases and for what reason it is appropriate to use these three methods and in what way they differ from each other.

Materials ◽  
2020 ◽  
Vol 13 (23) ◽  
pp. 5559
Author(s):  
Agnieszka Koson-Schab ◽  
Janusz Szpytko

The paper deals with the problem of applicability of the metal magnetic memory (MMM) technique in the crane structural inspection and monitoring. The MMM method does not require the external magnetization of a structure that results in reduction of downtime of maintenance operations. Measurement of the intensity of the self-magnetic leakage signal can be an alternative to other non-destructive methods used for inspection of a large crane’s structure and equipment. However, the complexity of the residual magnetization effect in the MMM technique is the problem with its application. Thus, the magnetic flux leakage behavior on the crane girder surface under different measurements and the crane’s load conditions is analyzed based on the results obtained during experiments carried out on the overhead traveling crane.


2011 ◽  
Vol 52 (3) ◽  
pp. 305-314 ◽  
Author(s):  
K. Yao ◽  
Z. D. Wang ◽  
B. Deng ◽  
K. Shen

2014 ◽  
Vol 940 ◽  
pp. 222-225
Author(s):  
Fei Fei Long ◽  
Jian Zeng Wang ◽  
Li Li ◽  
Jun Ru Zhao

Ensuring the safe operation of pipeline and monitoring it to prevent sudden accidents are an important task of current nondestructive testing work because of our country is in the peak period of long-distance pipeline construction. Welding cracks are common and most dangerous flaw in the root of the failure of the welded joints . Metal magnetic memory method is the only viable detection , evaluation method currently used for diagnosing the stress-strain state of serving welding crack in the early stages. So this article designs weld cracks of the general pipeline, establish a method to detect pipeline weld crack by metal magnetic memory method.


2014 ◽  
Vol 605 ◽  
pp. 139-142
Author(s):  
Seong Uk Hong ◽  
Yong Taeg Lee ◽  
Seung Hun Kim ◽  
J.H. Na

Recently, the interest in maintenance and repair of existing concrete structures have increased, and it is typical to use non-destructive testing methods such as rebound hardness test or ultrasonic pulse velocity method to execute maintenance and repair of structures efficiently. Many non-destructive testing methods are being used in practice such as at construction sites, but verification for site applications are quite inadequate. Thus, this study intends to evaluate the applicability of Impact Echo Method which is one of the non-destructive testing methods using stress wave. Total of four specimens were planned and produced. The thickness of concrete slab members was estimated using I.E(OLSENs Freedom Data PC with Win.TFS Software Version 2.5.2). The estimated materials of concrete members by IE was found to be IE-1 specimen 178mm, IE-2 specimen 197mm, IE-3 specimen 191mm, and IE-4 specimen 263mm, and the error rate was found to be 4.22%~18.67% (average 9.6%), showing that they are relatively well in agreement. In this study, the experiments were executed with the objective of estimating the thickness of concrete slab members using Impact Echo Method. Through this study, the applicability of thickness estimation in concrete slab members using impact echo method could be confirmed.


Author(s):  
Sheng Bao ◽  
Pengfei Jin ◽  
Zhengye Zhao ◽  
Meili Fu

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