Verification of Filling of Cable Ducts by Modern Diagnostic Methods

Abstract

A mayor problem in bridge engineering is the insufficient knowledge concerning the condition of prestressing reinforcement, especially in prefabricated bridge girders, which is largely related to the measure of grouting of cable duct. Therefore, this article deals with non-destructive methods that could verify the filling of cable duct with grout along their entire length, not just randomly in a few selected places. That is why it was decided to use modern non-destructive devices like GPR Live (8000), HILTI PS 1000 and Pundit 250 Array.

Measurement of asphalt concrete base thickness using ultrasonic pulse echo

“…First, the initial impulse is recorded on the screen, then the impulse of the defect inside the environment (echo of the defect) or the echo of the back wall. [4,5] The thickness of the structure, or the depth of the detected defect, can be determined from the exact time the ultrasound passes through the examined environment. Given the known speed of propagation of ultrasonic waves through the environment under investigation and the time t, which indicates the time between sending and recording the reflected signal from the back wall, the depth of the defect can be determined as d:…”

“…Based on the previous experience of the authors, the ultrasonic pulse echo method was chosen for these measurements, which is very suitable for measuring the thickness of the structure, possibly delaminations and cracks. [3,4]…”

Detection of Internal Defects and Failures of Concrete Structures Using Non-Destructive Methods

“…The whole measuring cycle is thus composed of a total of 28-A scans, as can be seen in Fig. 3, [2]. For ultrasonic pulse echo measurements, depth information is determined by the pulse velocity.…”