In recent years, innovative strengthening of reinforced concrete structures for industrial and civil use by external reinforcement based on carbon fiber has been widely used. However, there are only a few application examples of this amplification technology in the water treatment and sanitation facilities construction and rehabilitation. Based on experimental and practical data, composite amplification systems provide significant results both when working structures in normal conditions, and when they are in aggressive environments. Compared to conventional structural materials, carbon fiber-based composite materials have higher strength, significant fatigue resistance, high elastic modulus, chemical and thermal resistance.This article discusses the calculating method for strengthening reinforced concrete crossbars for coating the construction of an underground purified drinking water reservoir reinforced with composite materials. Based on the calculation methods, the reinforcing feasibility is substantiated. This work was carried out according to the results of a crossbars survey. In order to achieve these goals, a survey was made of the crossbars of the treated drinking water tank, the actual effective loads on the reinforced concrete crossbars were determined, the need to strengthen the examined structures according to the results of calibration calculations was determined, recommendations were developed to strengthen the examined structures of the reservoir construction. A survey of the structures of the structure, as well as an assessment of their technical condition, was carried out taking into account the requirements of current regulatory documents.

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