Complex characteristic for forecasting durability of hydraulic concrete

Abstract

The paper analyzes operating conditions of hydraulic structures, as well as the main types of external influence with temperature and humidity variations. The purpose of the research is to highlight the main parameters which will be able to assess the actual durability of concrete hydraulic structures in the process of their design. The authors use methods developed in Samara Architecture and Civil Engineering Institute to determine concrete physical and mechanical characteristics. Thus, these methods help accurately assess concrete durability, frost resistance and water resistance. These methods are based on theoretical studies of the processes of concrete destruction by means of non-destructive acoustic methods. The the energy conception developed by A.A. Griffits and S.N. Zhurkova's kinetic serve as a scientific basis for the methods. Theoretical research and its analysis of concrete destruction processes from various kinds of external influence was confirmed by results of standard measurements. The research showed that durability of concrete, that is speed of its destruction, depended on two groups of physical and mechanical characteristics. One of the groups evaluates the initial structure of concrete, while the second group characterizes the speed of the material loading . The paper proposes a forecasting method of frost resistance and water-resisting properties of concrete according to its physical-mechanical characteristics. It also introduces an indicator of their assessment which is named the length of the reduced crack. The proposed indicator has a good correlation with frost resistance and water-resisting properties . Besides, the proposed method can be used not only in laboratory conditions, but also in construction production directly on the construction site.