Abstract

The use of internal-crystallization chemical admixtures of different types is increasingly practiced as an essential part of new innovative waterproofing systems for buildings and facilities, capable of successfully replacing many conventional waterproofing systems – plaster coatings, sprayed, rolled, membranes, etc. The principle is known of action of different types of internal crystallization additives in the composition of the concrete, as a result of which an additional increase in the impermeability of the concrete section is sought, resp. with a contribution to the general waterproofing of buildings and facilities. In such a connection, especially in the presence of established defects, a case for arbitral assessment of the adequate presence (or not) of such admixtures reasonably arises, provided that they have been previously agreed upon between the parties in the investment process. The report discusses a proposed innovative research method for qualitatively and quantitatively assessment to establish the presence of a crystallization admixture in the composition of hardened concrete used for the construction of the defective building structure with impaired waterproofing ability.
Standard test methods are able to determine basic physical and mechanical characteristics of both types of concrete – without and with additives. The specialized structural methods (low-temperature gas adsorption BET-method, differential-thermal analysis and scanning electron microscopy) in turn have a high information capability regarding the features of the formed internal structure of the two types of concrete in question. On the basis of the obtained integral results, an objective conclusion can be formed as to whether or not such a chemical admixture has been added to the project concretes.