[ES] El diseño de puentes, a diferencia de lo que ocurre con el diseño de edificios o con el diseño de túneles ha dejado de lado la consideración de la acción del fuego hasta la fecha. Este vacío normativo, combinado con la gran repercusión económica y social de colapsos de puentes en el pasado como consecuencia de incendios, ha motivado un rápido incremento del número de estudios relativos a la ingeniería frente al fuego en el ámbito de los puentes. Aunque la acción del fuego no resulta del todo desconocida en el ámbito de las estructuras, sí que existen una serie de singularidades que impiden la trasposición directa de recomendaciones o de modelos de fuego simplificados ya desarrollados en otros campos que ya incorporan la acción del fuego en el diseño. En este contexto, el trabajo que a continuación se expone parte de un incendio ocurrido en el estado de Alabama en 2002, cuyas consecuencias fueron la demolición de un puente mixto de 37 metros de vano central, para plantear y validar una metodología que aborda el problema de forma numérica mediante tres modelos acoplados secuencialmente: modelo de incendios, modelo térmico y modelo mecánico Realizada una validación a nivel general se descubre que, aunque la configuración geométrica final obtenida se ajustan bastante a la realidad, la definición del incendio ha supuesto un gran número de hipótesis. Es por ello que se decide, en una segunda parte, realizar una campaña experimental que permita registrar la potencia del fuego, las temperaturas del gas y del acero y las flechas en un puente construido ad-hoc en el campus de la Universitat Politècnica de València. Este puente experimental tenía un vano único de 6 m de luz y fue sometido a cargas de fuego de hasta 1.3 MW. Mediante el empleo de los registros realizados en la campaña experimental se ha validado el modelo de incendio, el modelo térmico y el modelo mecánico. Con todo ello se ha puesto en evidencia la importancia del viento en la acción del fuego, la magnitud de los gradientes térmicos espaciales y la urgencia de desarrollar procedimientos simplificados que permitan la incorporación del fuego como acción en el ámbito de los puentes Las validaciones específicas de cada modelo han permitido además llegar a una serie de conclusiones de gran interés para la realización de futuras campañas experimentales en puentes a mayor escala. / [CAT] El disseny de ponts, a diferència del que passa amb el disseny d'edificis o amb el disseny de túnels ha deixat de banda la consideració de l'acció del foc. Aquest buit normatiu, combinat amb la gran repercussió econòmica i social de col·lapses de ponts com a conseqüència d'incendis, ha motivat un ràpid increment del nombre d'estudis relatius a l'enginyeria del foc del foc en l'àmbit dels ponts. Encara que l'acció del foc no resulta del tot desconeguda en l'àmbit de les estructures, sí que hi ha una sèrie de singularitats que impedeixen la transposició directa de recomanacions o de models de foc simplificats ja desenvolupats en altres camps que ja incorporen l'acció del foc al disseny. En aquest context, el treball que a continuació s'exposa part d'un incendi ocorregut a l'estat d'Alabama en 2002 i que va provocar la demolició d'un pont mixt de 37 metres de va, per plantejar i validar una metodologia que aborda el problema de forma numèrica mitjançant tres models acoplats seqüencialment: model d'incendis, model tèrmic i model mecànic Realitzada una validació a nivell general es descobreix que, encara que la configuració geomètrica final obtinguda s'ajusta en gran mesura a la realitat, la definició de l'incendi ha suposat un gran nombre d'hipòtesis. És per això que es decideix, en una segona part, realitzar una campanya experimental que permeta registrar la potència del foc, les temperatures del gas i de l'acer i les fletxes en un pont construït ad hoc al campus de la Universitat Politècnica de València. Aquest pont experimental presenta un va únic de 6 m de llum i va ser sotmès a càrregues de foc de fins a 1.3 MW. Mitjançant l'ús dels registres realitzats a la campanya experimental s'ha validat el model d'incendi, el model tèrmic i el model mecànic. Amb tot això s'ha posat en evidència la importància del vent en l'acció del foc, la magnitud dels gradients tèrmics espacials i la urgència de desenvolupar procediments simplificats que permetin la incorporació del foc com a acció en l'àmbit dels ponts Les validacions específiques de cada model han permès a més arribar a una sèrie de conclusions de gran interès per a la realització de futures campanyes experimentals en ponts a major escala. / [EN] To date, the fire action has been left aside in the bridge design despite this action has been widely considered in other structures such as building and tunnels. This regulatory vacuum, combined with the great economic and social impact of bridge collapses in recent times as a result of fires, has led to a rapid increase in the number of studies related to fire engineering in the field of bridges. Although the action of fire is not entirely unknown in the field of structures, there are a number of singularities that prevent the direct transposition of recommendations or simplified fire models from such fields. In this context, the study started by using a real fire which occurred in the state of Alabama in 2002 and led to the demolition of the 37-meter main span of a composite concrete and steel bridge to introduce and validate a methodology that numerically addresses the problem by uncoupling the problem in three different models: fire model, thermal model and mechanical model. Once the validation was accomplished at a general level, it was discovered that, although the geometrical data were quite adjusted to reality, the definition of the fire had involved a large number of hypotheses. That is why carrying out an experimental campaign to record the power of the fire, the gas and steel temperatures and the vertical deflections of a bridge built ad-hoc on the campus of the Universitat Politècnica de València became a priority. This 6-meter single span experimental bridge was subjected to fire loads of up to 1.3 MW. Through the use of the information recorded during the experimental campaign, the fire model, the thermal model and the mechanical model were validated. Moreover, the importance of wind in the action of fire, the magnitude of spatial thermal gradients and the urgency of developing simplified procedures which allow the consideration of fire as an action in the field of bridges were also highlighted. Last but not least, the validation of the different models allowed the author to include useful guidelines in order to define future experimental campaigns with more powerful fires and longer span bridges. / Alós Moya, J. (2018). Análisis de la respuesta frente al fuego de puentes mixtos multijácena [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/116625 / TESIS

This thesis deals with bridging of a lowland valley and the creek Dolanský in the section Jánovce – Jablonov on the Slovak motorway D1. Four variants of the bridge have been developed. Subsequently prestressed single box gilder with large overhangs that are supported by precast struts was selected as the most suitable variant. The construction of the bridge will take place in a formwork suspended on overhead launching scaffolding. The static assessment according to the Europan standard has been drawn up for this variant. The load of the bridge is projected according to the ČSN EN 1991-2 - Traffic loads on bridges and the dimensoin of concrete structures according to the ČSN EN 1992-2 - Concrete bridges - Design and detailing rules. The calculation of load is done using computer software SCIA Engineer 10.1 and Midas Civil.

This thesis contains diagnostics of a reinforced concrete girder bridge in the municipality of Újezd u Brna. The aim is to conduct an inspection of the bridge, gather quality photo-documentation of defects and failures and design and conduct a diagnostic examination of such extent that would be necessary for judging the load bearing capacity of the bridge. The result of this thesis is the determined load bearing capacity and a proposal of measures required to keep the bridge functional.

The subject of this thesis is the design and assessment of the bridge construction across the deep valley on highway traffic. From three variants, which were compared to each other, was the most suitable further examined. The solved structure is made of post-tensioned concrete, and is formed with cell box girder with transverse overhangs, which are supported by prefabricated struts over the length of the bridge. The load was considered by the European Standard EN 1991-2 - Traffic loads on bridges and dimensioning according to EN 1992-2-Design of concrete structures - Concrete bridges - Design and detailing rules.

The aim of this diploma thesis is to design and assess highway bridge. The structure is located on the D1 motorway section bridging a wide valley between the Slovak villages Doľany a Klčov. Three variants have been created – box girder bridge with transverse overhangs, a pair of girder bridge and a pair of box girder bridges. The various proposals were compared with each other. For the most valuable option is selected prestressed box girder bridge with transverse overhangs, which are supported by prefabricated concrete struts. The selected proposal was subsequently elaborated in detail, the load-bearing structure is analyzed using Scia Engineer 16. In calculating the internal forces is adjusted for the effects of construction methods, even as time-dependent analysis TDA. When designing the load-bearing structure it is considered the action of permanent load, also loading from transport and temperature. The structure is assessed for serviceability and ultimate limit states according to current standards. The bridge deck is built by incremental launching method. The principle of this method consists of building the segments in a casting yard located behind the bridge abutment. Each segment is matchcast against the previous one and prestressed to the section of structure already built. The whole superstructure is then jacked forward a distance equal to the length of this segment. This process is repeated until the bridge deck is in its final position. Chosen method of construction is very fast and efficient, to the country in the valley isn´t damage during construction.

The subject of diploma thesis is designing multi-span highway bridge over Řepovský potok valley, dirt roads and biocorridor. Three variants of bridge were designed and one of them – box girder 10 span bridge, has been chosen. Bridge deck is made from cast in place post tension prestressed beam. Load-bearing structure is concreting step by step on fixed and moving support. Total length of bridge is 560 m. The analysis of structure was projected on several computational models. They have been made in software Midas Civil and SCIA Engineer 18.1. The assessments of ultimate limit state and serviceability limit state were made in all steps of building in longitudinal and cross direction. In the analysis in longitudinal direction is included the time dependent analysis. Structural design was made in software MS Excel according to valid standards. Finally, drawing documentation and visualization were made.