The aim of this article is to determine conceptual basis of the term ‘time’ including the trends of interaction processes as separated constructive parts and the whole buildings at the operation in natural environment (geological sphere, water flow, and atmosphere) and the system of maintenance. When studying the processes of construction functioning, particularly hydraulic tunnels, time is an essential factor which determines their operational conditions and reliability. Water management system was presented as an interaction model of hydraulic facilities and the environment. During this interaction the movement of flows of energy and matter occurs, that determines the level of entropy (operational conditions) of constructive elements and the whole construction. In general, the pattern of entropy changes reflects past, present and future operational conditions of the construction. Entropy changes of operation conditions for constructions determine by irreversible processes and related to physical aging of building materials (concrete, ferroconcrete, metal, and ground) of separated constructive elements and the whole structure. During the investigations it was found that entropy increasing in the unit volume of the component or structure per unit time expresses the function of dissipation or conversion of the free energy to the bound. The greater value of free energy is related to the higher level of operational conditions and the level of technical and environmental safety respectively. In deterministic description of interconnection processes, interaction and relationship of hydraulic facilities and the environment, operational regimes of main canal, and maintenance service, “arrow of time” determines the trend of changes in operation conditions. As a result of the research, it is established that factor of time determines the aging of hydraulic facilities and other systems and follows by vulnerability increasing for all impacts, as well as decreasing of functional ability (operability), and this fact doesn’t account in existing techniques. It is revealed that inability of construction with the lapse of time to withstand against destruction has the same origin as energy dissipation that is the aging is an equivalent to the entropy increasing which is the measure of disorder in any system.
Keywords: time, irreversibility, change, entropy, functional reliability, safety.
