Alkali-silica expansion potentiality of Erzeni riverbed aggregates (Albania) and the risk of corrosion in concretes produced with them

Abstract

The environmental and fuel efficiency reasons led the industry of building raw materials to develop new technologies for production of cements. The cements being produced have high alkali content which in combination with some sorts of aggregates may influence the chemistry of the concrete mixture that may cause long term harmful effects to concrete structures. In this paper it is succinctly reviewed a part of scientific research work done on the possibility of the manifestation of the harmful effects caused by Alkali-Silica Reaction (ASR) on concretes made of high alkali cements and riverbed aggregates of Albania, in particular of those of Erzeni River, which is the most exploited one in Albania. The treatment of this topic has been a necessity and is considered very important for building industry in Albania, where traditionally low alkali cements have been produced and used. Especially in the period of transition, when high alkali cements started to be used both from import and domestic production, it is considered very important the study of the suitability of the riverbed aggregates in concrete produced with high alkali content cement since there are no ways of preventing ASR after the concrete has been placed. The results and recommendations of this study serve to increase the builder's awareness of the need of proper investigation, from this point of view, of the raw materials prior to construction. They also contribute to environment protection both by recommending alternative aggregates to riverbed ones and by helping to avoid the degradation, in timeframe, of concrete structures.