00982193

Monograph

http://onlinepubs.trb.org...y/NCHRP96_Final_Report.pdf

This Innovations Deserving Exploratory Analysis (IDEA) project developed and demonstrated the feasibility of a nondestructive ultrasonic technique based on modified split spectrum processing (SSP) and its rationalization using a statistical spectral histogram technique (SHT) for field evaluation of highway concrete structures. Following the selection, evaluation and optimization of the initial instrumentation, a new algorithm was developed that allowed automatic selection of optimum or near optimum parameters for SSP and performing the SSP using the selected parameters. A software system was developed that allowed spectral histogram analysis for the direct determination of the frequency region without trial and error. The software was successfully tested for several cases including the determination of thickness and internal defects of a concrete slab. The combination of SSP with SHT reduced the noise thereby significantly improving the interpretation of the received high frequency ultrasound. Also, the computerized form made the application simple and rapid. The improved process can further be extended to produce two-dimensional images for improved diagnosis of concrete structures.

This NCHRP-IDEA investigation was conducted by OPTIMUM Engineering Research, Lansdowne, Pennsylvania. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved

NCHRP-IDEA Project 96

NCHRP-IDEA 96

English

25 p.

2004-11

NCHRP-IDEA Program Project Final Report

Appendices (2) ; Figures (8) ; References (2) ; Tables (3)

Algorithms; Concrete structures; Defects; Histograms; Nondestructive tests; Slabs; Thickness; Ultrasonic tests

Innovations Deserving Exploratory Analysis (IDEA) (Program)

Spectral histogram technique; Split spectrum processing

Bridges and other structures; Design; Highways; I24: Design of Bridges and Retaining Walls

TRIS, TRB

Nov 30 2004 12:00AM