Title: Precautions for the Use of Nondestructive Testing on Site

Author(s): C. T. Tam

Publication: Symposium Paper

Volume: 128

Issue:

Appears on pages(s): 85-100

Keywords: field tests; impact hammer tests; measuring instruments; nondestructive testing; penetration tests; ultrasonic tests; General

DOI: 10.14359/3666

Date: 11/1/1991

Abstract:
The use of nondestructive testing in the laboratory is well-documented and standard specifications are available. However, when these nondestructive testing methods are used on site, additional factors have to be taken into consideration to enable meaningful interpretation of measurements obtained. This aspect of knowledge has not received sufficient attention for standard specifications to be drafted. Suggestions are put forward in this paper on precautions to be taken when applying nondestructive testing on site. The methods of testing discussed include the magnetic method of concrete cover or bar size determination, the rebound hardness, ultrasonic pulse velocity and the penetration resistance (Windsor Probe) test. The methods of calibration in the laboratory are reviewed and the ways to check on equipment and its calibration during site work are proposed. The information to be recorded and the interpretation of data are discussed. The need for trained personnel to carry out site testing, as well as experienced professionals to interpret test results, is emphasized.