Subject of this master thesis is a flyover bridge over the road II/434 and flood-land. As a load-bearing construction is designed two-beam structure. Traffic loads on this structure are considered according to standard ČSN EN 1991-2. The structure design is based on resultant stressing according to standard ČSN EN 1992-2.

The aim of this thesis was to suggest two alternatives of a prestressed concrete bridge structure over the river Jihlava in Ivančice and to design the chosen one. The structure was designed as a one-span frame bridge with the span range of 46,0 m. Both design and relevant drawing documentation of the slab, abutment and strip foundation was made.

The diploma thesis describes the design of curved, pre-stressed concrete bridge over the highway D1. A variant, that is chosen for detail analysis, is a spine girder construction as a continuous beam with 3 spans. The thesis solves the construction to limit states according to applicable European standards (Eurocodes). There are developed clear and detailed drawings and visualization of the bridge.

The diploma thesis deals with design and assessment of the main structure of the road bridge which leads the road I/55 over the highway D1. The thesis contains three designs of the construction. One design was chosen for detail solution. The thesis includes statical analysis, drawing documentation and visualization.

The master's thesis object is to design a road bridge over the Jihlava river. Three studies are proposed from which pre-stressed two-beam structure with three spans variant is chosen. A detailed structural analysis elaborated and the bridge is analysed according to ultimate limit state and serviceability limit state. Drawing documentation and visualisation were made. The structure design is based on the European standarts.

Concrete is considerably stronger in compression than it is in tension. When cracks form in concrete members, the flexural stiffness of the member decreases and the deflection increases which increases the overall size of the member. Prestressing concrete remedies this problem by inducing a compressive stress in the concrete thereby reducing the net tension in the member and increasing the load required to crack the member. Traditional prestressing is generally limited to large, straight members. During the last decade, shape memory alloys (SMA) have become more prevalent in engineering and civil engineering applications. The shape memory effect refers to the contraction of the SMA when it is heated to its austenite phase. When a prestrain is induced in the SMA, it can be recovered when it goes through the phase change. Nitinol, a NiTi shape memory alloy was used in this research. Thin, steel cables were also tested to provide a comparison. Two different Nitinol alloys were studied in this research. The alloy M wires were elongated to 8% stain while the alloy X wires were prestrained by the manufacturer. The wires were cast into thin concrete beams and once cured, the beams were heated and a phase change from martensite to austenite occurred in the Nitinol. As a result, the Nitinol contracted and compressed the concrete. The SMA fibers are randomly oriented and allow prestressing to occur along all three axis. This is ideal for thin, curved specimens. Third-point bending tests showed that the SMA fibers prestressed the concrete and upon reheating the cracked specimens, the shape memory effect provides partial crack closure.

The ultimate shear capacity of prestressed concrete beams is difficult to predict accurately, especially after being in service for an extended period of time. The Utah Department of Transportation asked researchers at Utah State University to experimentally determine the existing shear capacity of 41-year-old prestressed, decommissioned concrete bridge girders and then provide recommendations on how to increase that ultimate shear capacity. This thesis presents the research findings that relate to the existing shear capacity of the prestressed concrete girders. Eight AASHTO Type II bridge girders were tested up to failure by applying external loads near the supports to determine their ultimate shear capacities. The measured results were then compared to calculated values obtained using the AASHTO LRFD bridge design code, and the ACI 318-08 design code. Prestress losses were also measured by means of a cracking test and then compared to values calculated according to the AASHTO prestress loss equations. Both the ultimate shear capacities and the residual prestress forces were used to evaluate the girders after being in service for more than 40 years.

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