Chukanova N. Improvement of organizational and technological decisions on monitoring the technical condition of old buildings.

The goal of ensuring serviceability and safety of old building facilities is the attainment of maximum duration of their life cycles that depend on their reliability. In its turn, such a reliability is determined by the quality of measurements and supervisions used for obtaining input data for conducting repairs during operation, timely revelation and correction of damages, prediction of trends in development of damages. The analysis of methods and technologies of instrumental measurements including those used during repair operations has been performed. The effects of measurements on the serviceability of old building facilities have been analyzed. The scope and quality of data collected with the use of instrumental methods affect the efficiency of decisions on improving of building performances. Therefore, the working hours expended for collecting such data affect the duration of building operation. The importance of inclusion of measuring operations in the scope of metrology that is legislatively regulated arises from the necessity to minimize risks of diminishing serviceability of building facilities including old ones as such risks can result in catastrophic material, social, cultural and historical consequences of their destruction. Correlation and interference of elements of information, technical and technological systems have been studied. It has been established that the evaluation of the nature of damages and threats connected with them are very important for building operation. Therefore the development of models and classification of factors affected the technical conditions will facilitate an increase in the efficiency of measuring systems. It has been established that with the use of system engineering methods it is possible to develop a structure model for properties of a diagnostic expert system. It was confirmed that the application of fuzzy knowledge bases allows development of adequate mathematical models based on experience of expert diagnosticians and experimental data. Such models will allow a decrease in the volume of initial samples that is generated on the basis of reliable diagnostic data on object conditions. In addition, the knowledge base can include information about costs of repair operations, prediction estimates concerning development of defects and others. A set of information tasks and procedures of their fulfillment to ensure the completeness of the information model of the integrated process of measurements on the monitored object have been generated. They include the procedures that are implemented by iteration (the object identification by attributes of defects and damages, geodesic conditions, climate and operational loads). The task of generation of a set of various monitoring methods for detection of the totality of possible (the most dangerous) defects in the system may be defined as a multilevel and multicriterion problem of discrete programming. In addition to the principal solutions such a problem includes the solutions for rational distribution of monitoring efforts by various stages of the object's life cycle, distribution of places and monitored parameters, planning of system maintenance with consideration to economic factors. The algorithm of selection of monitoring methods with consideration to accuracy, cost and timeliness of obtaining measurements has been developed. The efficiency of application of utility functions that describe the dependence of the utilities of alternative variants on the estimates of such alternative variants has been confirmed. It has been established that the timeliness of obtaining measurements is the most important factor as it facilitates the timely making of a decision for preventive measures. The cost of work is more important than the accuracy. The measures of utility have been obtained and evaluated. These measures characterize the utility (value) of the monitoring methods with consideration to technical and economic factors - the more is the measure of utility the more effective is the application of the corresponding method of monitoring.