The Microsensor Technology Using to Identify the Initiation Time of Impact Induced Elastic Waves

Lung-Jieh Yang; Tsung-Tsong Wu; Shung-Wen Kang

doi:10.6180/jase.2002.5.3.01

The Microsensor Technology Using to Identify the Initiation Time of Impact Induced Elastic Waves

Lung-Jieh Yang This email address is being protected from spambots. You need JavaScript enabled to view it.¹ , Tsung-Tsong Wu² and Shung-Wen Kang¹

¹Department of Mechanical and Electro-Mechanical Engineering Tamkang University Tamsui, Taiwan 251, R.O.C.
²Institute of Applied Mechanics National Taiwan University Taipei, Taiwan 106, R.O.C.

Received: March 11, 2002
Accepted: June 20, 2002
Publication Date: September 1, 2002

Download Citation: ||https://doi.org/10.6180/jase.2002.5.3.01

ABSTRACT

The microsensor technology was used here to identify the initiation time of an impact shock. The shock excitation caused by an impact sphere with a diameter of 4-6 minimeters could generate transient elastic waves in concrete structures. Such elastic waves with frequency above 100 kHz are the active emission sources for defect detection in the non-destructive testing (NDT) of concrete using transient elastic waves. In this paper, an impact sphere, which was packaged with a piezoresistive microsensor, was fabricated to verify this new idea. The microsensor after packaging has the maximum output voltage of 100 mV and the rise time less than 5 microsecond subjected to a sphere impact. The promising result of the initiation time experiment showed that the calibrated (short circuit) signal was left behind the microsensor signal for 40 nanoseconds.

Keywords: Transient Elastic Wave, Impact Initiation, Microsensor

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