Structural health monitoring (SHM) using ambient vibration has become a tool in evaluating and assessing the condition of civil structures. For bridge structures, a vibration-based SHM system uses the dynamic response of a bridge to measure modal parameters. A change in a structure’s modal parameters can indicate a physical change in the system, such as damage or a boundary condition change. These same modal parameters are sensitive to environmental factors, mainly temperature. Statistical models have been utilized to filter out modal parameter changes influenced by temperature and those caused by physical changes. Statistical models also help describe the relationship between modal parameters and environmental conditions. The Lambert Road Bridge is a concrete integral abutment bridge located south of Sacramento, California, and is studied through this paper. A SHM system has been installed and has been recorded for 3 years. Three months of SHM records will be used to understand how the bridge’s natural frequencies typically change due to temperature. First, temperature was observed to be the driving force behind many of the SHM records. A linear relationship was found between the structure’s natural frequency and temperature. Collinearities between potential predictor variables were noticed. Initial linear regression analyses were completed with a bridge average temperature. Certain strain gauge regression models were used as “base” models to eliminate other regression models that potentially were altered by aliasing. These base models, and the other seven corresponding models, showed a direct linear relationship between temperature and natural frequency. It was concluded that changes in boundary conditions due to bridge expansion have a greater effect on global dynamic properties than material property changes due to temperature. Stepwise linear regression followed the initial regression modeling. Eight thermocouple readings were consistently being selected in the stepwise process and were chosen to be the main predictor variables. Due to collinearities among the predictor variables, ridge regression was completed to eliminate any unstable variables. The final six sensors’ locations indicate that longitudinal, transverse, and depth gradients are all important factors in the linear regression models of this relationship. Comparing the multiple linear regression models to single-variable regression models with the highest averaged adjusted R2 values, a minimum percent difference of 21% and 19% was seen for the first and second natural frequencies, respectively. It was also concluded that these multiple linear regression models explained more of the variability in the natural frequencies and would be a better model to use to filter out temperature effects.

The aim of this thesis is the relocation of roads II/431 and III/4317 near Kojátky village. This is due to the unsuitable layout of current routes which were poorly arranged because of too many horizontal and vertical curves with small radius. Another reason was a bad technical state of bridge structures, one of them was in serious disrepair. The project deals with the relocation of current roads to more suitable routes including the option allowing access to the nearby estates and the connection to the existing cart tracks. The project also addresses two bridge structures across the streams.

This thesis deals with the reconstruction of the existing road arch bridge using free transverse prestressing cables. Cables are laid in holes drilled in the shape of strut. The holes routed diagonally across the front wall of the bottom edge of the arch. The work also includes the stability of long front wall. This is solved by means of spacer frames led across the road. The reconstruction can be done partially limited service.

The Diploma thesis deals with the design of the bridge construction that conveys the road I/11 across the Bystry brook and the local road between Nebory and Oldřichovice. The construction is designed in four options, one of which was selected is the variation of the prestressed onebeam construction of four fields and the lenght of bridging 106,6 m. Calculation of the effects of the load is carried by a computer program Scia Engineer. Assessing the design is done in accordance with applicable European standards EN 1992-1-1. It is also elaborated well arranged drawing documentation, construction process and visualization of the bridge.

This thesis deals with the reconstruction of a road bridge with two simple fields over the river Olše in Třinec. The reconstruction of the bridge structure is designed in two versions, for which there is an executed design and assessment of a supporting structure according to applicable standards. The calculation of internal strenght is carried out by using the Scia Engineer 2016 program. This work contains a static calculation, a drawing documentation , an economical comparison of variants and visualization.

Since 1 January 2010 it is a requirement to use the European standards, Eurocodes, in Sweden when constructing bridges. One chapter that has caused an extra amount of problems for the engineers is the one about fatigue analysis, which resulted in us doing this thesis. To do this we had to read all of the Eurocodes that direct, or indirect deals with fatigue and calculating of such. We have read the background documents for the Eurocodes and master’s thesis in the subject. We also studied the calculations of bridges constructed by different construction firms. We have chosen to limit the thesis to discuss only road bridges made of concrete due to the lack of method for verification of concrete in the national appendix. There is a need for clarification of what method to use. To make sure that this thesis will be of use to the constructors, we have presented easy-to-use instructions for how to calculate fatigue on reinforced concrete bridges. We have also calculated an example of a bridge in two spans where we present the calculations in Excel more thoroughly. Fatigue of concrete is in many cases not the critical factor and it can most often be verified by simple methods. The concrete reinforcement is more often the subject to fatigue, but verification can relatively easy be done with the method described in the national appendix if a good Excel- or MathCAD sheet is used. / Sedan den 1 januari 2010 är det krav i Sverige att för bro- och anläggningskonstruktioner använda de nya europeiska standarderna, eurokoder, för dimensionering. Ett kapitel som vållat stora problem för brokonstruktörer är kapitlet om utmattningslaster och dimensionering för dessa vilket ledde till att vi gjorde detta examensarbete. Vi har läst igenom de eurokoder som direkt och indirekt behandlar utmattning och utmattningsberäkningar, granskat bakgrundsdokument till eurokoderna samt läst examensarbeten som handlar om utmattning. Dessutom har vi också granskat beräkningar från ett flertal broar som olika konsultföretag konstruerat. Vi har valt att avgränsa arbetet till att enbart handla om utmattning av vägbroar i armerad betong. Detta har vi gjort för att metoder för verifiering av betongen i vägbroar inte är definierade i de nationella tilläggen till eurokoderna. Därför behövs ett förtydligande av vilka metoder som är lämpliga att använda. För att konstruktörer ska ha praktisk nytta av detta examensarbete, har vi redovisat en beräkningsgång med kommentarer och dessutom utfört egna beräkningar för en förenklad variant av en plattbro i två spann där vi redovisar beräkningarna i Excel mer ingående. Vad vi har kommit fram till är att armeringen ofta är mer utsatt för utmattning än betongen men verifieringsmetoden beskriven för armeringen i det nationella tillägget är en metod som är relativt lätt att använda med ett bra Excel eller MathCAD-ark.

The topic of this thesis is detailed design of supporting structure of continous box girder bridge across a deep valley called Lazný creek. The bridge have to pass the second class road with category S 9,5. The design is processed by two options. The chosen option is designed as a girder with five spans 44,8 m + 55 m + 55 m + 55 m +44,8 m. Total length of bridge is 268,57 m, the main girder is gradually cast into the formwork suspended on a special ceiling scaffolding. The axis of the bridge is in a plan straight with the constant transversal slope 2,5 %. The thesis contains six models in software SCIA ENGINEER. Part of the work is situated on time depended analysis with construction phases. Assesment of ultimate limit states and serviceability limit states were done by hand according to the valid standards and regulations. Structural analysis, drawing documentation and vizualization are parts of this work.

My master's thesis aims to design a bridge construction spanning road III/443 over road I/44. Three versions were created one of which has been developed further. It is a three span bridge with a total spread of 77.5 meters. Proposal and evaluation of bridge construction is done unassisted. Static analysis is done using Scia Engineer program. Construcion evaluation is done by valid EU norms ČSN EN 1992-1-1. Mechanical drawing, building procedure and visualisation is also included.

The aim of the diploma thesis is the design of a continuous bridge construction of five fields in the direction of the town Albrechtice - Opava. The bridge overcame local roads and railway tracks and is part of the bypass of Albrechtice. From the three proposed variants, a pre-stressed two-beam structure was selected for the detailed solution and it is assessed according to the limit states and includes the effects of gradual construction. Further detailed drawings are drawn up.

Thesis describes the design and assessment of a plan view of a curved road bridge, which is a part of an elevated crossing transferring directional divided communication and tram line of public transport in Brno. There are four variants of cross sections designed, from which is selected bicameral cross section with arched angled bottom plate, which should be aesthetically pleasant to impress in an urban environment. Static calculation is processed and design is assessed by current European standards. Then clear and detailed drawings, the process of construction and visualization of the bridge are processed.