Kovalchyk Y. Strength, fracture toughness and deformation of prestressed concrete beam bridges spans

The strength, crack resistance, deformation of prestressed concrete beams with reinforcement of the European rope type by the action of single, low-cycle and cycle loads have been researched. The full scale prestressed bridge beams on carrying capacity in bending moment and transverse force were tested.The possibility of using the method of digital image correlation analysis of the stress-strain state of reinforced concrete structures has been established.Researched work on endurance of prestressed reinforced concrete beams laboratory samples has been prestressed by rope reinforcement of European type.The data about the reducing of prestressed beams strength due to the impact of high level low-cycle loads were received.The construction support, review, static and dynamic tests and theoretical analysis of a continuous pre-stressed monolithic span overpass at different stages of work were completed. Acoustic emission data were got. The data on the impact thermostressed state that depends of hydration reaction in the concrete array during constructing bridges spans on their crack resistance.The recommendations for using effective concrete spans the previous stress on roads with high traffic according crack resistance criteria for using acoustic emission method.The economic feasibility of using prefabricated monolithic spans of prestressed beams on roads with high intensity compared with prefabricated monolithic spans of beams with ordinary reinforcement was shown. It recommends during constructing concrete spans transport constructions and road's traffic categories with more than 10,000 cars/day to use only pre-stressed structures.The recommendations for designing monolithic prestressed concrete bridges with spans stressed on concrete (post- tension systems) were developed.