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Knowing the quality of concrete is very important, because this type of material is part of the design and implementation of most structures such as bridges, buildings, tunnels, among others, in this investigation non-destructive tests were carried out on test specimens of using ultrasound, which were designed and developed in the concrete laboratory at Santo Tomas University in Bogotá D.C. taking into account for its preparation a dosage of the estimated concrete mixture in order to obtain specimens with a compressive strength of 3500psi, 2500psi and 1500psi, in such a way, the specimens were allowed to cure for a period of 28 days, ensuring that they achieved their maximum compression strength. As mentioned above, non-destructive ultrasound tests were applied in order to determine the quality of the manufactured concrete specimens, thus, an ultrasound system is proposed that makes it possible to pass an acoustic wave through a concrete specimen, this was proposed with the purpose of measuring the velocity with which the wave passes in the volume of this material, known as the ultrasonic pulse velocity. Therefore, the respective velocities for each of the concrete specimens were measured, thus finding a relationship between the ultrasonic pulse velocity and the compressive strength, which finally makes possible the evaluation of the manufactured concrete specimens.

The noninvasive technique of ultrasonic pulse rate (UPV) is increasingly used in the evaluation of the quality of concrete, providing information about the integrity of structures and preventing possible disasters. Therefore, for its direct application, it is necessary to have a prior correlation between the noninvasive UPV technique and the invasive uniaxial compression resistance (UCS) assay. While correlations have been determined by various authors, each has been given specific conditions and guidelines by the authors because there is no standardized way to perform the correlations. Rather, there are only experimental tests that have generated experimental correlations-both linear and logarithmic-with different graphic shapes. Therefore, this research aims, first, to validate the aforementioned relationship, which allows the compressure resistance of concrete (f'c) to be determined for a given design of concrete mixtures following the American Concrete Institute (ACI. 211.1.). Second, it aims to determine the most accurate trend and the possibly correct form of the correlation plot between the UPV and UCS. In the first instance, 15 plain concrete specimens were designed with an f'c of 28 MPa, whose dosage was carried out following the method of ACI. 211.1. Then, UPV and UCS tests were performed according to regulations in the first 28 days of curing the specimens. Finally, a logarithmic correlation was obtained between the UPV values and the values of the invasive tests for the UCS of concrete. A graphical analysis with some existing correlations of other investigations was then performed, and a similarity in the logarithmic tendency, with a coefficient of determination greater than that of the linear trend, was observed.

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Considering the possibility that from the area of electronics can be provided feasible solutions in the field of non-destructive testing, this chapter present a prototype and methodology that allows energize an ultrasound transducer. This system is used to evaluate for detecting weld failures at the junctions of metallic parts. Subsequently, in order to validate the design quality of that source, a computer system that allows control of a card developed ultrasound. Finally, it is implemented the ultrasonic imaging by time of flight diffraction technique, in order to obtain an objective comparison methodology to both systems.