The Assessment of Durability of Fibre Concretes with Dense Aggregate and Concrete Recyclate from the Results of Permeability and Diffusion Tests

Abstract

The mechanical and deformation characteristics of mass concrete are considerably improved by adding long structural fibres. This addition, however, does not always extend the durability of concrete. One of the key factors in the evaluation of durability of fibre concretes is the assessment of permeability of their surface layer using one of the non-destructive methods. In this research, three of these methods were used: two permeation methods with a gaseous medium, TORRENT and CO2 permeability method, and the British ISAT with a liquid medium, on the grounds of their simplicity of application and their possible combinability. The test results show that both TORRENT and ISAT methods can be used to assess the durability of both concrete and fibre concrete with dense aggregate. In the case of concrete containing concrete recyclate, however, the TORRENT method was not effective. Also the method of determining the permeability for CO2 was not suitable for the concrete with concrete recyclate. Even for other concretes this method was too complicated and too dependent on the marginal conditions of the measurement.

Experimental determination of the influence of fresh concrete’s composition on its resistance to water and de-icing chemicals by means of two methods

“…[5][6][7] The quality of the surface layer together with the porosity of the concrete also determines its resistance to the intrusion of liquids and gases from the environment, i.e., permeability. Permeability is determined, e.g., by TPT [5][6][7][8] , GWT and ISAT. 9 Other options for assessing the surface layer of concrete are methods for determining the resistance of cement concrete to water and de-icing chemicals.…”

Statistical view of evaluating concrete-surface-layer permeability tests in connection with changes in concrete formula

“…A number of papers have been published within the project, such as 8,9 . Permeability itself is addressed in [10][11][12] . The research described in this paper summarises an experiment whose goal was to assess the influence of concrete composition on the results of the tests determining the concrete surface layer's permeability, i.e., TPT, GWT and ISAT.…”