Assessment of the Integrity of Piles by Impedance Log Technique

Abstract:

The objective of this paper is to investigate the capabilities of the Impedance Log method in profiling the geometry of a pile along its length. The main idea of this method is to introduce a transient stress wave into the pile and then utilize the reflected signals to obtain the impedance profile of the pile. Any anomaly, which results in changes in impedance, would be detected by this method. In this study, four model piles with plan defects of weak zone or neck were constructed and tested using Seismic Echo, Impulse Response, and Impedance Log pile integrity nondestructive testing methods. Results of these tests show that interpretation of signals using the Impedance Log method is more straightforward than the other two methods. It is concluded that the Impedance Log technique is a tool with high potential for evaluating the integrity of piles.

• Periodical: Key Engineering Materials (Volumes 321-323)
• Pages: 340-343
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.321-323.340
• Online since: October 2006
• Authors: Jiunn Ren Lai, Chih Peng Yu, Shu Tao Liao
• Keywords: Impedance, Integrity, Pile, Stress Wave

References

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0 Impedance Ratio.

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0 Distance from Pile Head (m) (a) Intact Pile Tested Profile Actual Geometry.

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0 Distance from Pile Head (m) (b) Single Neck Pile Tested Profile Actual Geometry.

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0 Distance from Pile Head (m) (c) Weak Zone Pile Tested Profile Actual Geometry.

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0 Distance from Pile Head (m) (d) Double Neck Pile Tested Profile Actual Geometry.