Researching and Strengthening Reinforced Concrete Crane Beams of Mukachevo Reinforced Concrete Plant

This paper formulates the problem and emphasizes its relevance. An analysis of recent studies and publications on inspecting and strengthening reinforced concrete structures of buildings and structures of long-term operation is also presented, and the purpose of researching and strengthening crane beams is formulated. The results of the natural researching and strengthening (01.07.1991) reinforced concrete pre-stressed crane beams of long-term operation at the Mukachevo Reinforced Concrete Products Plant are presented. A number of defects and damages were found in the molding workshop on beams B-1, B-2 and B-3, as well as cracks in the supporting sections of beam B-1 with a disclosure exceeding the permissible limits of regulatory documents. In particular, the force (fatigue) cracks with openings exceeding the permissible limits, concrete crushing, signs of corrosion of reinforcement and concrete, and, in some areas, concrete delamination was found. The data on the concrete strength of emergency beams determined by non-destructive testing are also presented. The figures show the tying of damaged beams and the reinforcement of beam support units. Based on this inspection, recommendations for strengthening the defective and damaged three crane beams were developed and possible options were given. Also, the bearing capacity of the crane beams was restored and the technology for implementing possible reinforcement options was presented. Based on the survey and research, recommendations for the technology of crane beams reinforcement were developed. The results of the repeated inspection (30.03.2023) after long-term operation are also provided. Based on these surveys, it turned out that the next change of ownership of the MRSP had been made and the situation of maintaining the operational characteristics of the main load-bearing structures had deteriorated significantly. It was noted that according to the "Guidelines for Inspection of Buildings and Structures to Determine and Assess Their Technical Condition" (Kyiv, 2017), the condition of the load-bearing and enclosing structures can be recognized as emergency (category 4). Based on the inspection and research, the relevant conclusions are made.