This thesis deals with bridge design as an important part of road design and layout. Bridges frequently dominate roads and railways, and are, in many cases, a prominent feature of the landscape. Discriminating selection of the type of bridge and material to be used, having regard to technical and aesthetic requirements is therefore essential. Road construction and bridge design are both applied arts in landscaping, and should be considered as such throughout the planning sequence. Since the main thrust of this thesis is directed toward the aesthetic and engineering aspects, no attempt has been made to include overall economic analyses or details of construction; however, to indicate the basic nature of the engineering principles and to demonstrate appropriate dimensions of bridge components, calculations and sketches of a few bridges are included. Various types of bridges are evaluated and discussed in terms of their accordance with modern environmental requirements. The design of the new bridge across the Alouette River at the U.B.C. Research Forest is taken as a particular case study, the analyses of this crossing showing that thoughtful selection of both bridge and location can not only enhance the landscape, but also improve route conditions. Engineers should blend their talents with nature so as to create a harmonious landscape. / Forestry, Faculty of / Graduate

It is proposed in this thesis that the imperfect systems of Cram and of Schubert be combined with some modifications.

This dissertation presents methodologies to develop bridge condition deterioration models which accounts for non-stationarity in the deterioration process with applications to Florida concrete and timber bridges. A critical and comprehensive review of bridge deterioration modeling approaches is presented with illustrative examples based on regression, stochastic Markov-chain, mechanistic and Artificial Neural Network (ANN) models. This study also develops a framework for relating the qualitative National Bridge Inventory (NBI) condition ratings with normalized resistance of the concrete bridge component with application to concrete bridge T-beams to reduce the subjectivity of the NBI condition rating. A systematic approach for the prioritization of bridges for inspection is developed using the multivariate regression modeling technique, and forecasting models are developed based on multiple relevant variables for both concrete bridge superstructure and substructure components. This dissertation also develops an approach for risk and reliability assessments of concrete and timber bridges based on non-parametric deterioration modeling techniques such as average time-in condition rating (ATICR) and Kaplan-Meier (K-M) survival (reliability) models, for probabilistic prediction of bridge safety while accounting for the partial information from the incomplete bridge condition observations. This study develops relative deterioration rates based on the ATICR and illustrates the time-dependent probability of deterioration of the concrete and timber bridge components based on K-M estimates. Further, the relationship of explanatory variables to the survival time is discussed and estimates are made for the median survival years for reinforced concrete solid slab decks. This dissertation presents the code developed in R for multivariate regression analysis and data-driven reliability analysis. Future research studies in bridge deterioration modeling are also presented. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2021. / FAU Electronic Theses and Dissertations Collection

"Infrastructures work to move goods, people, energy and information around, establishing pathways and nodes that make connectivity possible" The potential for architects to discover the overlaps between the human, mechanical, and natural conditions of the city may allow the redevelopment of deficient infrastructure to simultaneously address other critical urban issues. What if the typical monofunctional infrastructure could be transformed into an urban experience that creates a new public landscape and enhances physical exchange? / 0 / SPK / specialcollections@tulane.edu

Two critical components of the United States civil infrastructure, bridges and roads, have deteriorated in the past two decades at an accelerated rate and are in need of maintenance and rehabilitation. Geosynthetics may have the potential to provide a long-term solution to some of the problems that are present in these roads and bridges. When installed properly, some geosynthetics can act as both a moisture barrier and stress absorption layer. However, the tack coat application rate is critical as an excessive amount can cause eventual slippage, while too little may result in debonding. A new geocomposite membrane, which is comprised of a low modulus PVC layer sandwiched between two layers of nonwoven geotextile, has recently been introduced for use in highway systems for water impermeability and strain energy absorption. A laboratory testing program was conducted to determine the optimum asphalt binder tack coat rate that needs to be applied in the field. To accomplish this, a fixture was designed to allow the application of cyclic shear loading at the geocomposite membrane interface when used as an interlayer simulating one of two situations: a concrete bridge deck overlaid with the geocomposite membrane, and an HMA overlay or a flexible pavement with the geocomposite membrane sandwiched between an HMA base layer and an HMA wearing surface. The research concluded that 1.40 kg/m2 of tack coat should be used when the geocomposite surface is in contact with an HMA base mix, 1.5 kg/m2 should be used when it is in contact with an HMA surface mix, and 1.75 kg/m2 should be used when it is in contact with concrete surfaces. However, these tack coat application rates are a function of the structural material type and the tack coat material type (binder performance grade). In addition, an analysis of the simulated bridge deck specimens with geocomposite membrane and the control samples, containing no membrane, shows distinct evidence that the membrane acts as a stress-absorbing material. / Master of Science

The purpose of this research was the investigation of the corrosion behavior of a low chromium-content stainless steel, ASTM A1010, for use in steel bridge members. This stainless steel has been marketed as a potential replacement for conventional structural steels for bridges located in highly-corrosive environments, with the potential to provide life-cycle cost savings. Further investigation of the corrosion behavior of A1010 in corrosive environments was required for three bridge-specific applications: the galvanic corrosion of A1010 connected to plates and fasteners composed of dissimilar metals; the crevice corrosion of A1010 plates connected with other A1010 plates; and the effect of varying surface preparation techniques on the corrosion behavior of A1010. These behaviors were studied through the implementation of an accelerated cyclic corrosion test, the modified SAE J2334 Surface Vehicle Standard specification. Results from the accelerated corrosion test indicated the following: galvanic corrosion rates of A1010 with dissimilar metal plates may result in accelerated corrosion rates of the dissimilar metal plates beyond desirable levels; connections to many non-stainless fastener types show cause for concerns with galvanic corrosion, while B8 Class 2 austenitic stainless steel bolt assemblies exhibited superior performance; the relative corrosion-resistance of A1010 is decreased in detailing susceptible to crevice corrosion; and finally, numerous abrasive blasting procedures appear to be suitable for use with A1010. / Master of Science / The purpose of this research was the investigation of the corrosion behavior of a recently-developed stainless steel, ASTM A1010, for use in steel bridges. This stainless steel has been marketed as a potential replacement for conventional structural steels for bridges located in highly-corrosive environments, and has the potential to provide cost savings to bridge owners over the life of the bridge. While the general properties of ASTM A1010 have been studied, further investigation was required for the corrosion behavior in bridge-specific applications. As a result, the corrosion behavior from three applications was investigated: A1010 connected to plates and fasteners composed of dissimilar metals; A1010 plates connected with other A1010 plates; and A1010 cleaned using different abrasive blasting procedures. Ultimately, these behaviors were studied through the implementation of an accelerated laboratory corrosion test which exposed A1010 plates to repeated cycles with controlled temperature, relative humidity, and exposure to corrosive substances. Testing results have shown important findings: significant concerns are associated with connecting different plate types to A1010 due to the high rates of corrosion expected on the dissimilar metals; connections to many fastener types show cause for concern, while one stainless steel type exhibited superior performance above the rest; the relative corrosion-resistance of A1010 is lessened in highly-corrosive environments; and finally, numerous abrasive blasting procedures appear to be suitable for use with A1010.

Orientador: Nilson Tadeu Mascia / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil e Arquitetura / Made available in DSpace on 2018-08-12T06:32:42Z (GMT). No. of bitstreams: 1 Sartorti_ArturLenz_M.pdf: 8739751 bytes, checksum: b8c521a2573d5e6622b0d27a97dc444a (MD5) Previous issue date: 2008 / Resumo: A existência de um grande número de pontes com problemas patológicos importantes motiva a pesquisa sobre este assunto. As pontes de pequeno e médio porte têm relevância significativa para o desenvolvimento econômico e social do país, pois devem assegurar o trânsito de pessoas, veículos e matérias primas e escoamento dos produtos gerados. No entanto, o estado precário em que se encontra grande parte das pontes em vias urbanas e rurais, dificulta o deslocamento, causando desconforto e insegurança aos usuários. Além disso, elevam-se os custos de transporte para os produtores e de manutenção para as prefeituras. Diante desta realidade, busca-se nesse trabalho, avaliar o estado de conservação de pontes de pequeno e médio porte em vias urbanas e rurais na região de Campinas (SP). Desta forma, um correto embasamento teórico do assunto permitirá a adoção da acertada atitude frente a um quadro patológico. Sendo assim, esta pesquisa foca uma ampla revisão bibliográfica abrangendo o estado-da-arte do projeto de pontes e da identificação das patologias nas estruturas metálicas, de concreto armado e/ou protendido e de madeira, e também visa estabelecer conceitos que serão aplicados quando da escolha do método corretivo. Além do embasamento teórico, buscou-se constatar "in loco" a manifestação de patologias em nove pontes na região do município de Campinas (SP), apresentando-se sugestões quanto à profilaxia e correção em cada caso. Para colaborar com as sugestões, foram desenvolvidos dois projetos de pontes tipo anexados à pesquisa, os quais são de estruturas mistas de aço-concreto e de madeira. Finalmente observa-se a partir da presente pesquisa, que existe a necessidade de um mapeamento rigoroso das pontes urbanas e rurais com vistas de elevar a vida útil e garantir maior segurança à sociedade. / Abstract: The existence of a great number of bridges with pathological problems motivates the research on this subject. The small and medium bridges have a main importance to the economic and social development of the country, due to they must guarantee the people, vehicle, and raw material transit and the flow of manufacture products. However, the precarious condition that a great part of the bridges is in the city and in the rural area and has difficult the movement, causing discomfort and insecurity to people. Besides, there is an increase of the cost of transport to the producer and of the maintenance to the town hall. In the presence of this reality, this work intends to evaluate the conservation state of small and medium bridges in the city and in the rural area in the region of Campinas (SP). Thus, a consistent theoretical base about this subject will permit to choose a right attitude on a pathological way and this research focuses on a complete review of bibliography covering the state-of-art of the bridge design and the pathological identify of steel, reinforced or prestressed concrete and wood structures and also will establish concepts that will be applied to the choice of a corrective method. Apart from this theoretical base, it was presented, "in loco", the pathological demonstration of nine bridges in the region of Campinas (SP), and proposed suggestions about the treatment and correction in each case. To collaborate with these suggestions, two pattern projects of bridges, which were of concrete and steel composite structure and of wood, were developed and annexed to this research. Finally, through this research it is noticed that there is a need of a rigorous mapping of the urban and rural bridges to elevate their useful life and to guarantee the right security to the society. / Mestrado / Estruturas / Mestre em Engenharia Civil

The main objective of this research is to estimate the sizes of riprap (loose rock) on highway or railroad embankments approaching bridges, that would be stable in major floods. Two assumptions about the flow direction were made: one horizontal to the bridge abutment and the other normal to the projection of the bridge abutment. Three dynamic conditions of stability of riprap were observed and classified as shaking, some movement, and large movement (washing out). Shaking is the most conservative criteria for design because it indicates more stability than is necessary, requires larger rock, and is less cost efficient. Some movement suggests a conservative design criteria and is the most desirable because it requires smaller riprap and is therefore less expensive. Large movement or washing out means the least stable condition; it may leave the structure as well as human lives exposed to danger.

published_or_final_version / Civil Engineering / Doctoral / Doctor of Philosophy

O presente trabalho se propôs a estudar os esquemas estruturais alternativos para pontes esconsas e avaliar as modelagens matemáticas possíveis através de softwares especializados, como o SAP2000 e STRAP2010, a fim de identificar as melhores soluções e modelos para cada caso. O objetivo foi o de aprimorar os modelos de cálculo, especialmente no que diz respeito à previsão das reações de apoio e das forças cortantes, ponto mais delicado de obras esconsas. O estudo baseou-se em soluções de superestrutura em laje e em grelha, com ou sem transversinas, com esconsidade variável entre zero e sessenta graus, eixo longitudinal reto, modeladas por barras e elementos finitos. Não foi objeto deste estudo a influência da meso e da infraestrutura dessas pontes nos esforços na superestrutura. / The present work is proposed to study alternative structural schemes for skew bridges and to evaluate possible mathematical modeling through specialized software, such as SAP 2000 and STRAP2010, in order to identify the best solutions and models for each case. The aim was to improve the calculation models, especially with regard to the prediction of the support reactions and shear forces, most delicate point in skew bridges. The study was based on slab or grid, with or without transversal beams, superstructure solutions, with variable skew between zero and sixty degrees, straight longitudinal axis, modeled through bars and shell elements. It was not purpose of this study the influence of meso and infrastructure of the bridge on its superstructure.