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The results of studies into the usefulness of 3D surface roughness parameters determined by 3D laser scanning, for the nondestructive evaluation of the pull-off adhesion of concrete layers are presented. Twenty-one 3D roughness parameters were identified. Their correlations with pull-off adhesion f b determined by the semi-nondestructive pull-off method were established. For two of the parameters, i.e. the texture aspect ratio ( Str ) and the peak material volume ( Vmp ) the correlation coefficient was found to be high. The possibility of the nondestructive evaluation of the pull-off adhesion on the basis of solely the existing concrete topography examinations is critically looked at. [ABSTRACT FROM AUTHOR]

This paper presents a new nondestructive way of identifying the values of pull-off adhesion between the concrete layers in concrete floors. It based on the roughness parameters of the base layer surface, using the nondestructive optical technique, and on the floor surface, using the nondestructive acoustic techniques and employing artificial neural networks (ANNs) for this purpose. The new way has a potential for being widely used in practice, whereby it may become possible to employ previously trained ANNs to identify the pull-off adhesion, without impairing the surface of the tested concrete floor. [ABSTRACT FROM AUTHOR]

The paper deals with the nondestructive identification of defective concrete zones in unilaterally accessible massive members, for example, access galleries in hydroelectric power plants. The concrete in such zones is, for various reasons, excessively porous. The authors propose to use state-of-the-art acoustic testing techniques, including ultrasonic tomography, integratively to detect and identify defective zones. An original methodology for such tests has been developed. The methodology is illustrated with an example of its practical application to a real civil engineering structure. [ABSTRACT FROM PUBLISHER]

Abstract: This paper presents the application of artificial neural networks to the identification of the pull-off adhesion of the concrete layers in floors on the basis of parameters evaluated on the structural layer surface by the nondestructive optical method and on the floor surface by the nondestructive of impulse-response and impact-echo acoustic methods. The tests were carried out on specially prepared model specimens of concrete floor. In order to vary pull-off adhesion in the specimens the surface of the base layer was prepared in four versions. The aim of the investigations was the neural prediction of the pull-off adhesion of the concrete layers in floors on the basis of nondestructive tests. This is of practical importance since in this way the condition of the surface of the tested floor is not impaired. [Copyright &y& Elsevier]