This thesis examines the development of a superstructure for a slab-on-girder wood-concrete composite highway bridge. Wood-concrete composite bridges have existed since the 1930's. Historically, they have been limited to spans of less than 10 m. Renewed research interest over the past two decades has shown great potential for longer span capabilities. Through composite action and suitable detailing, improvements in strength, stiffness, and durability can be achieved versus conventional wood bridges. The bridge makes use of a slender ultra-high performance fibre-reinforced concrete (UHPFRC) deck made partially-composite in longitudinal bending with glued-laminated wood girders. Longitudinal external unbonded post-tensioning is utilized to increase span capabilities. Prefabrication using double-T modules minimizes the need for cast-in-place concrete on-site. Durability is realized through the highly impermeable deck slab that protects the girders from moisture. Results show that the system can span up to 30 m while achieving span-to-depth ratios equivalent or better than competing slab-on-girder bridges.

This thesis examines the development of a superstructure for a slab-on-girder wood-concrete composite highway bridge. Wood-concrete composite bridges have existed since the 1930's. Historically, they have been limited to spans of less than 10 m. Renewed research interest over the past two decades has shown great potential for longer span capabilities. Through composite action and suitable detailing, improvements in strength, stiffness, and durability can be achieved versus conventional wood bridges. The bridge makes use of a slender ultra-high performance fibre-reinforced concrete (UHPFRC) deck made partially-composite in longitudinal bending with glued-laminated wood girders. Longitudinal external unbonded post-tensioning is utilized to increase span capabilities. Prefabrication using double-T modules minimizes the need for cast-in-place concrete on-site. Durability is realized through the highly impermeable deck slab that protects the girders from moisture. Results show that the system can span up to 30 m while achieving span-to-depth ratios equivalent or better than competing slab-on-girder bridges.

External post-tensioning is an attractive technique for strengthening reinforced concrete structures because of its ability to actively control stresses and deflections, speed of installation, minimum interruption for the existing structure, and ease of inspection under service conditions. However, external prestressing implies exposing the tendons to the environment outside the concrete section, which may lead to corrosion in steel tendons. Therefore, the interest in using fiber reinforced polymer (FRP) tendons, which are corrosion resistant, has increased. The present work investigated, experimentally and analytically, the flexural performance of reinforced concrete beams strengthened with externally post-tensioned Carbon FRP (CFRP) tendons, under monotonic and fatigue loadings. Initially, tensile fatigue tests were carried out on CFRP tendon-anchor assemblies to assess their response under repeated cyclic loads, before implementing them in the beam tests. New wedge-type anchors (Waterloo anchors) were used in gripping the CFRP specimens. The assemblies exhibited excellent fatigue performance with no premature failure occurring at the anchorage zone. The fatigue tests suggested a fatigue limit of a stress range of 10% of the tendon ultimate capacity (approximately 216 MPa). Monotonic and fatigue experiments on twenty-eight beams (152x254x3500 mm) were then undertaken. Test parameters included the tendon profile (straight and double draped), the initial loading condition of the beam prior to post-tensioning (in-service and overloading), the partial prestressing ratio (0.36 and 0.46), and the load ranges applied to the beam during the fatigue life (39% to 76% of the yield load). The CFRP tendons were post-tensioned at 40% of their ultimate capacity. The monotonic tests of the post-tensioned beams suggested that overloading the beam prior to post-tensioning increased the beam deflections and the strains developed in the steel reinforcing bars at any stage of loading. However, overloading had no significant effect on the yield load of the strengthened beam and the mode of failure at ultimate. It also had no discernable effect on the increase in the tendon stress at yielding. The maximum increase in the CFRP stress at yield load was approximately 20% of the initial post-tensioning stress, for the in-service and overloaded beams. A very good performance of the strengthened beams was observed under fatigue loading. The fatigue life of the beams was mainly governed by the fatigue fracture of the internal steel reinforcing bars at a flexural crack location. Fracture of the bars occurred at the root of a rib where high stress concentration was likely to occur. No evidence of wear or stress concentration were observed at the deviated points of the CFRP tendons due to fatigue. The enhancement in the fatigue life of the strengthened beams was noticeable at all load ranges applied. Post-tensioning considerably decreased the stresses in the steel reinforcing bars and, consequently, increased the fatigue life of the beams. The increase in the fatigue life was slightly affected by the loading history of the beams. At the same load range applied to the beam, increasing the amount of the steel reinforcing bars for the same post-tensioning level decreased the stress range in the bars and significantly increased the fatigue life of the strengthened beams. In the analytical study, a monotonic model that predicts the non-linear flexural response of the CFRP post-tensioned beams was developed and implemented into a computer program. The model takes into account the loading history of the strengthened beams prior to post-tensioning (in-service and overloading). Good agreement was obtained between the measured and the predicted monotonic results. A strain-life based fatigue model was proposed to predict the fatigue life of the CFRP post-tensioned beams. The model takes into consideration the stress-strain history at the stress raisers in the steel bars. It accounts for the inelastic deformation occurring at the ribs during cycling and the resulting changes in the local mean stresses induced. Good agreement between the experimental and predicted fatigue results was observed. A step-by-step fatigue design approach is proposed for the CFRP externally post-tensioned beams. General conclusions of the study and recommendations of future work are given.

This master‘s thesis deals with the behaviour of strengthened reinforced concrete beams. The aim was to evaluate different types of strengthening in comparison not only with each other, but also with the reference beam. Three reinforced concrete beams were fabricated for the purpose of the thesis. The first served as a reference beam, the second was strengthened with carbon lamella glued to the lower edge of the reinforced concrete beam, and the last one was strengthened with unbonded post-tensioning system. Subsequently, they were all loaded by a four-point bending. An evaluation was then carried out which shows that the two strengthened reinforced concreate beams resist the load much better than the reference beam. In the conclusion, different utilization possibilities of both methods are listed, as well as the disadvantages that must be taken into account when designing.

This diploma thesis is about analysis of post-tensioned cantilever beam, which is part of cantilever of commercial building. The main part of thesis is evaluation of behavior of building structure in time and determination of the most suitable staging. Next part of thesis is design and evaluation of reinforced slab and beam.

The diploma thesis deals with the design of a road bridge on the I/57 expressway over the relocation of the cycle path, the Opavice river and the local road, which involves the relocation of the access to the waterworks. The bridge structure is located in the territory of the town of Krnov. A study of the area's bridges is part of the project and three studies have been prepared. Study A was chosen for detailed processing. It is a continuous box girder bridge with three spans. The superstructure is designed as a monolithic, post-tensioned structure. A sliding girder is being investigated for the structure's construction. Scia Engineer 18.1 is used to do the load effects computation. Only the consequences of vertical load effects have been addressed, with no consideration of horizontal load effects. The structure was evaluated using limit states, taking into account the impact of construction on its design.

Concrete block masonry is a common building material used worldwide, including Canada. Reinforced masonry buildings, designed according to the requirements of recent building codes, may result in seismically safe structures. However, unreinforced masonry (URM) buildings designed and constructed prior to the development of modern seismic design codes are extremely vulnerable to seismic induced damage. Replacement of older seismically deficient buildings with new and seismically designed structures is economically not feasible in most cases. Therefore, seismic retrofitting of deficient buildings remains to be a viable seismic risk mitigation strategy. Masonry load bearing walls are the most important elements of such buildings, potentially serving as lateral force resisting systems. A seismic retrofit research program is currently underway at the University of Ottawa, consisting of experimental and analytical components for developing new seismic retrofit systems for unreinforced masonry walls. The research project presented in this thesis forms part of the same overall research program. The experimental component includes design, construction, retrofit and testing of large-scale load bearing masonry walls. Two approaches were developed as retrofit methodologies, both involving reinforcing the walls for strength and deformability. The first approach involves the use of ordinary deformed steel reinforcement as internally added reinforcement to attain reinforced masonry behaviour. The second approach involves the use of internally placed post-tensioning tendons to attain prestressed masonry behaviour. The analytical component of research consists of constructing a Finite Element computer model for nonlinear analysis of walls and conducting a parametric study to assess the significance of retrofit design parameters. The results have led to the development of a conceptual retrofit design framework for the new techniques developed, while utilizing the seismic provisions of the National Building Code of Canada and the relevant CSA material standards.

External post-tensioning is an attractive technique for strengthening reinforced concrete structures because of its ability to actively control stresses and deflections, speed of installation, minimum interruption for the existing structure, and ease of inspection under service conditions. However, external prestressing implies exposing the tendons to the environment outside the concrete section, which may lead to corrosion in steel tendons. Therefore, the interest in using fiber reinforced polymer (FRP) tendons, which are corrosion resistant, has increased. The present work investigated, experimentally and analytically, the flexural performance of reinforced concrete beams strengthened with externally post-tensioned Carbon FRP (CFRP) tendons, under monotonic and fatigue loadings. Initially, tensile fatigue tests were carried out on CFRP tendon-anchor assemblies to assess their response under repeated cyclic loads, before implementing them in the beam tests. New wedge-type anchors (Waterloo anchors) were used in gripping the CFRP specimens. The assemblies exhibited excellent fatigue performance with no premature failure occurring at the anchorage zone. The fatigue tests suggested a fatigue limit of a stress range of 10% of the tendon ultimate capacity (approximately 216 MPa). Monotonic and fatigue experiments on twenty-eight beams (152x254x3500 mm) were then undertaken. Test parameters included the tendon profile (straight and double draped), the initial loading condition of the beam prior to post-tensioning (in-service and overloading), the partial prestressing ratio (0.36 and 0.46), and the load ranges applied to the beam during the fatigue life (39% to 76% of the yield load). The CFRP tendons were post-tensioned at 40% of their ultimate capacity. The monotonic tests of the post-tensioned beams suggested that overloading the beam prior to post-tensioning increased the beam deflections and the strains developed in the steel reinforcing bars at any stage of loading. However, overloading had no significant effect on the yield load of the strengthened beam and the mode of failure at ultimate. It also had no discernable effect on the increase in the tendon stress at yielding. The maximum increase in the CFRP stress at yield load was approximately 20% of the initial post-tensioning stress, for the in-service and overloaded beams. A very good performance of the strengthened beams was observed under fatigue loading. The fatigue life of the beams was mainly governed by the fatigue fracture of the internal steel reinforcing bars at a flexural crack location. Fracture of the bars occurred at the root of a rib where high stress concentration was likely to occur. No evidence of wear or stress concentration were observed at the deviated points of the CFRP tendons due to fatigue. The enhancement in the fatigue life of the strengthened beams was noticeable at all load ranges applied. Post-tensioning considerably decreased the stresses in the steel reinforcing bars and, consequently, increased the fatigue life of the beams. The increase in the fatigue life was slightly affected by the loading history of the beams. At the same load range applied to the beam, increasing the amount of the steel reinforcing bars for the same post-tensioning level decreased the stress range in the bars and significantly increased the fatigue life of the strengthened beams. In the analytical study, a monotonic model that predicts the non-linear flexural response of the CFRP post-tensioned beams was developed and implemented into a computer program. The model takes into account the loading history of the strengthened beams prior to post-tensioning (in-service and overloading). Good agreement was obtained between the measured and the predicted monotonic results. A strain-life based fatigue model was proposed to predict the fatigue life of the CFRP post-tensioned beams. The model takes into consideration the stress-strain history at the stress raisers in the steel bars. It accounts for the inelastic deformation occurring at the ribs during cycling and the resulting changes in the local mean stresses induced. Good agreement between the experimental and predicted fatigue results was observed. A step-by-step fatigue design approach is proposed for the CFRP externally post-tensioned beams. General conclusions of the study and recommendations of future work are given.

This diploma thesis is about designing the structure of roof of swimming stadium. Three solutions are created - concrete arc with tie, steel truss slab and concrete pretensioned membrane. One choosed solution - concrete pretensioned membrane - is afterwards developed. In the beginning there are several designs of geometry fulfilling the requirements for given type of structure being created. In part of static calculation, the parametrical mathematical model in form of macro in APDL language for Ansys software has been created. Afterwards all the parameters (initial state of cables, level of pretension, dimensions of membrane and peripheral frame, etc.) has been optimized in order to the membrane be fulfilling criterias for ultimate limit state and serviceability limit state. Afterwards other selected parts of structure has been checked. On basis of designed geometry and design checks in static calculation the drawings of conctruction and designed parts has been created. In the end, the 3D model of the structure has been created in graphical software Rhinoceros. Then visualizations of structure in concstruction stages and after completion has been rendered.

Master’s thesis deals with diagnostics and reconstruction of neo-gothic chapel in Medlice. Summary of appropriate testing methods for this chapel is compiled. Visual examination of whole structure have been performed by diagnostics. Masonry element strength was found out at specimens which had were taken out from structure (drill cores and whole bricks). Masonry elements also was tested by Schmidt hammer LB. Mortar was tested by Kucera’s drill. Masonry strength required for static calculation was computed from achieved values. After examination of all structure defects have been designed reconstruction by post-tensioning.