The article examines the problem of strengthening reinforced concrete floor slabs with insufficient load-bearing capacity during reconstruction or increased loads. A method is proposed involving partial integration of additional monolithic reinforced concrete beams through pre-formed openings in the slab. Various approaches are analyzed to ensure composite action between the slab and beams. The study aims to theoretically and experimentally determine slab deflection and develop optimal implementation methods. Preliminary calculations of reinforcement and dowel parameters are provided. Numerical modeling using the LIRA-SAPR software confirms the effectiveness of the solution. Drawings of test specimens are also included. Results show that the added beams reduce slab deflection and improve strength and stiffness, but cause a complex stress–strain state requiring thorough evaluation before application.
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