reinforcement.

This article describes strengthening normal cross-section of reinforced concrete beams with prestressed reinforcement under load. The samples of RC beam with 2100 mm. length, 100 mm width, and 200 mm height was tested. As beam’s tension reinforcement A500C Ø12 mm rebar was chosen. A240C Ø8 mm rebar was chosen as compressed reinforcement. Transverse reinforcement – A240C Ø8 mm rebar located in the supporting area with step 50–100 mm. Class of the concrete was C32/40. The beams were tested for a pure flexure. The load was added using the hydraulic cell in the thirds of the span.