Residual resource of bridges and bridge structures.

Abstract

The article is devoted to the definition of current methods of assessing the residual resource of bridges and bridge structures. Extending the service life of bridges and determining the residual resource of bridges and bridge structures remain topical problems because capital restoration or construction of new bridges is a very time-consuming and costly process for any country in the world. An analysis of current foreign and domestic regulatory documents and research on the general state of the problem concerning the types of destruction, the impact of accidents, and external environmental factors were carried out. A large volume of information on the nature of occurrence and accumulation of damage in reinforced concrete bridge structures shows that the destruction of bridges is mainly influenced by production factors and environmental factors. The gradual destruction of the structure occurs as a result of the accumulation of various types of damage that arise from multiple repeated temporary loads, accidents, temperature changes, and the appearance of corrosion processes. To calculate the residual and total life of bridge elements, the crack resistance criterion was chosen, which takes into account the type of bridge construction, purpose, and operating conditions. As a determining parameter, the crack opening width was chosen for the elements of road and city bridges reinforced with tension rod reinforcement, and the limit value of this parameter was established. In the absence of large failure statistics, it is suggested to use a probabilistic-physical approach to durability assessment. The main parameters of the probabilistic model with DM-failure distribution – are the average rate of change of the determining parameter and the coefficient of variation of the generalized degradation process. The results of the calculations show values that correspond to statistical and regulatory indicators. Qualitative collection of information on parameters of the destruction of bridges and bridge structures and a probabilistic-physical approach to assessing the real technical condition of the object provide more accurate calculation results and allow for predicting the moment of reaching their maximum allowable value.