摘要 |
A device and method to nondestructively measure bulk stress in a member by employing an acoustic source, preferably an ultrasonic source, a processor, and a uniquely configured acoustic sensor package. The sensor package is configured to transmit both a longitudinal wave signal and a shear wave signal into the member. The processor is configured to capture reflections of the two impressed signals along a principal stress axis of the member and calculate the roundtrip time of the two signals. Knowing the length of the member along a principal stress axis, from the roundtrip times of the two signals, two velocities are calculated. By employing an equation that calculates bulk stress as a function of these shear and longitudinal wave velocities, a measure of bulk stress is calculated via the processor. The device measures bulk stress of a member that offers limited access in its permanent installation, such as dam reinforcements.
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