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Symmetrical steel moment frames that are subjected to sidesway forces due to unsymmetrical live loads will undergo sidesway. The P-delta effects on a moment frame under the influence of sidesway forces is studied. The effective length method is used for the second-order analysis specified in the American Institute Steel Construction - Load and Resistance Factor Design (AISC-LRFD). This study investigates the P-delta effects on a multi-story, multi-bay steel moment frame subjected to sidesway forces caused by various unsymmetrical live load patterns. The study focuses on the interaction of axial and bending moment in the columns. The actual response of a moment frame is estimated by amplifying the results of a first-order elastic analysis using moment magnification factors. The moment magnification factors for each story of the steel moment frame are summarized.

This thesis documents the fabrication, testing techniques, and response of a plastic scale model of an orthotropic bridge deck. To economically investigate a two-lane steel bridge deck, plastic AcrylicR was used as a modeling material. Welds were simulated with dichloromethane, a capillary action solvent, and PS-30, a polymerizable cement. Deflections were measured with laboratory dial guages while strains were monitored with strain guages mounted on the deck. The response of the deck to AASHO vehicle axle loads was compared with a discrete element computer program used to analyze orthotropic bridge decks continuous over flexible supports. Results indicate good correlation between measured and computed values for deflection and strains.

We present a generalization of Signorini's method to the case of live loads which allows us to derive approximate solutions to some pure traction-value problems in finite elastostatics. The boundary-value problems and the corresponding compatibility conditions are formulated in order to determine the displacement of the system up to the second-order of approximation. In particular, we consider the case of homogeneous and isotropic elastic bodies and we solve the following two traction-value problems with live loads:(i) a sphere subjected to the action of a uniform pressure field;(ii)a hollow circular cylinder whose inner and outer surfaces are subjected to uniform pressures. Then, starting from these solutions, we suggest experiments to determine the second-order constitutive constants of the elastic body. Expressions of the second-order material constants in terms of displacements and Lame' coefficients are determined. / Master of Science

" The determination of strain is an important step when using a mechanistic-empirical structural design, such as the AASHTO 2002 Design Guide. This thesis investigated the use of accelerated pavement testing system on Hot Mix Asphalt pavements to determine actual transverse and longitudinal strains under loads of varying frequency at different temperatures. A Model Mobile Load Simulator (MMLS3) was used in this study. Laboratory compacted pavement slabs were instrumented with thermocouples for monitoring the pavement's temperature, and with strain gauges in transverse and longitudinal directions at the bottom surface to measure strain. The slabs were subjected to loading by the MMLS3, running at different speeds. The pavement slab and accelerated loading equipment were enclosed in an environmental chamber to control temperatures during testing. Strains were also determined from layered elastic analysis after determining modulus values by two different methods - Resilient modulus testing and Witczak’s dynamic modulus equation. Comparisons of pavement strains calculated through the use of layered elastic design software and actual strains obtained during loading were made. The test results have shown a significant difference between strain values obtained using an instrumented pavement slab and those obtained with the use of standard resilient modulus values or dynamic modulus values determined by using a typical layered elastic design model. To avoid the discrepancies, two approaches are proposed - The first is modeling strain with accelerated pavement testing and the second one is using a correction factor. "

Reinforced Concrete Box Culverts (RCBCs) are an integral part of the national and international transportation infrastructure. The National Bridge Inventory Standards (NBIS) requires that all bridges, which include culverts with spans ≥ 20 ft. (6.1 m), be load rated for safe load carrying capacity in accordance with the AASHTO Manual for Bridge Evaluation (MBE). In Kentucky, the Transportation Cabinet manages more than 15,500 bridges, of which almost 1,400 are bridge size culverts. Of the 1241 bridge size RCBCs that were being evaluated in Kentucky between 2015 and 2018, 846 were 2-cell culverts (or 68%). The objective in this study is to evaluate 2-cell RCBCs using the finite element (FE) method and to propose dead load and live load demand equations that can be used to determine the capacity demand ratio (C/D) and the load rating. The results indicate that the maximum dead load forces (positive and negative moments, and shear) vary linearly with respect to an increase in fill height, while the variation is bi-linear for the maximum live load forces. The proposed equations are derived in terms of the clear span and fill height. The results also indicated that, for fill heights greater than 10 ft (3 m), the maximum live load positive bending moments are less than 10% of their dead load counterparts. The primary advantage of the proposed equations lies in their simple formulation when analyzing and designing 2-cell culverts, which in turn alleviates the need to conduct a detailed finite element analysis to determine the maximum forces in 2-cell RCBCs.

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Fundação de Amparo a Pesquisa do Estado de Minas Gerais / The analysis of the service life of the structures of reinforced concrete should contemplate probabilistic processes due to the random of the parameters that influence in the mechanisms that affect the life of the structure. In these processes, besides the application of structural reliability techniques, it is necessary the characterization of the variables that influence in the deterioration mechanisms. The main objective of this work is to analyze variables related to the forecast of service life of the concrete structures, particularly of residential buildings, in urban areas far from the marine coast, from a point of view of the probabilistic behavior and propose functions of density of probability and representative statistical parameters. To get that, it was carried out a data survey in four residential buildings and in environmental organs. Later it was made the statistical analysis of them and the adjustment of continuous functions of densities of probability, by the Kolmogorov-Smirnov goodness-of-fit test. The studied variables were the temperature, the relative humidity, the concentration of carbon dioxide in the atmosphere, the weight of people and the furniture and the area of occupation of the furniture. As results, it was found out that to the temperature and relative humidity variables, for the city of Uberlândia, a function of normal density of probability can be adopted, with an average of 22,8ºC and a standard deviation of 4,4ºC for the temperature and an average of 65,06% and a standard deviation of 17,15% for the relative humidity. For the CO2 concentration in the urban atmosphere of the city of São Paulo, it resulted in a density function of log normal of probability with an average of 1083 ppm and a standard deviation of 168 ppm. For the live loads variable: weigh of the people the found values were 0,74 kN and standard deviation of 0,13 kN, with a function of normal density of probability. For the weight of the furniture the adjusted function was the normal with average of 0,22 kN/m2 and standard deviation of 0,15 kN/m2. The obtained results will be important for the study of the service life of reinforced concrete structures and they are constituted in a first regional base of data. / A análise da vida útil das estruturas de concreto armado deve contemplar processos probabilísticos devido a aleatoriedade dos parâmetros que influenciam nos mecanismos que afetam a vida da estrutura. Nesses processos, além da aplicação de técnicas de confiabilidade estrutural, é necessária a caracterização das variáveis que influenciam nos mecanismos de deterioração. O objetivo geral do trabalho é analisar variáveis relacionadas à previsão de vida útil das estruturas de concreto, particularmente de edifícios residenciais, em regiões urbanas distantes da costa marítima, desde um ponto de vista do comportamento probabilístico, propondo funções de densidade de probabilidade e parâmetros estatísticos representativos. Para tal, foi realizado o levantamento de dados em quatro edifícios residenciais e em órgãos ambientais. Posteriormente foi feita a análise estatística dos mesmos realizando-se o ajuste de funções contínuas de densidades de probabilidade, mediante o teste de aderência Kolmogorov-Smirnov. As variáveis estudadas foram a temperatura, a umidade relativa, as concentrações de dióxido de carbono na atmosfera, o peso dos móveis e de pessoas e a área de ocupação dos móveis no ambiente. Como resultados, foram encontrados que as variáveis temperatura e umidade relativa, para a cidade de Uberlândia, pode ser adotada uma função de densidade normal de probabilidade, com média 22,8ºC e desvio padrão de 4,4ºC para a temperatura e média de 65,06% e desvio padrão de 17,15% para a umidade relativa. Para a concentração de CO2 na atmosfera urbana da cidade de São Paulo, resultou uma função de densidade log - normal de probabilidade com média 1083 ppm e desvio padrão de 168 ppm. Para a variável de sobrecarga: peso do usuário (pessoas) os valores encontrados foram 0,74 kN e desvio padrão de 0,13 kN, com uma função de densidade normal de probabilidade. Para o peso do mobiliário a função ajustada foi a normal com média de 0,22 kN/m2 e desvio padrão de 0,15 kN/m2. Os resultados obtidos serão importantes para o estudo da vida útil de estruturas de concreto armado e se constituem em uma primeira base de dados regional. / Mestre em Engenharia Civil

Thesis (MScEng)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Different types of live loading due to traffic may act on bridges. The focus of this study is on normal traffic loading according to the South African specification of TMH7. Heavy vehicles are not included in normal traffic loading. TMH7 represents the code of practice for the design of highway bridges and culverts in South Africa. The aim of the study is to provide an insight into the flexural analysis of skew bridges, under the effects of normal traffic loading. The need for the study arose since the specification of TMH7 does not explicitly specify application patterns for normal traffic loading. Only the intensity of normal traffic loading is specified and it should be applied to yield the most adverse effects. For these reasons, a set of so-called standard application patterns are investigated and developed through the course of this study. The envelope of the values from the standard application patterns are compared to the most adverse application pattern for flexural effects in certain design regions of the bridge deck. Flexure, as in the context of this study, translates into the bending and twisting of the bridge deck under loads. A number of numerical experiments are performed for typical single span and multi-span continuous carriageways, where the standard application patterns are compared to the most adverse application patterns. The results from the numerical experiments are documented and compared as the angle of skew of the bridge deck increases in plan-view. For this purpose, the development of effective and specialized software was necessary. It was found that the set of standard application patterns can be used as a preliminary approximation for the most adverse effects of normal traffic loading, for specific flexural resultants in certain design regions of a bridge deck. However, for a large number of secondary flexural effects, the set of standard application patterns did not represent a good approximation for the most adverse values. / AFRIKAANSE OPSOMMING: Verskillende tipes lewendige belasting, as gevolg van verkeer, kan op brûe inwerk. Die fokus van die studie is op normale verkeers-belasting volgens die Suid-Afrikaanse spesifikasie van TMH7. Swaar-voertuie word nie ingesluit by normale verkeers-belasting nie. TMH7 verteenwoordig die kode vir die ontwerp van padbrûe en duikers in Suid-Afrika. Die doel van die studie is om insig te verskaf in die buig-analise van skewe brûe, as gevolg van die werking van normale verkeers-belasting. Die rede vir hierdie studie ontstaan aangesien die spesifikasie van TMH7 nie eksplisiet aanwendingspatrone vir normale verkeers-belasting voorskryf nie. Slegs die intensiteit van normale verkeersbelasting word voorgeskryf en dit moet aangewend word om die negatiefste effekte te verkry. Vir hierdie redes word 'n versameling van sogenaamde standaard aanwendings-patrone deur die loop van die studie ondersoek en ontwikkel. Die omhullings-kurwe van die waardes wat deur die standaard patrone gelewer word, word vergelyk met die waarde van die aanwendings-patroon wat die negatiefste buig-effek in sekere ontwerp-areas van die brugdek veroorsaak. Buig-effekte, soos van toepassing op hierdie studie, verwys na buig en wring van die brugdek as gevolg van belastings. 'n Aantal numeriese eksperimente, vir enkel-span sowel as multi-span deurlopende brugdekke, word uitgevoer en die standaard aanwendings-patrone word vergelyk met die aanwendings-patrone wat die negatiefste waardes lewer. Die resultate van die numeriese eksperimente word gedokumenteer en vergelyk soos die hoek van skeefheid van die brugdek in plan-aansig toeneem. Vir hierdie doel is die ontwikkeling van effektiewe en gespesialiseerde sagteware dus nodig. Daar is gevind dat die standaard aanwendings-patrone, vir spesifieke buig-resultante in sekere ontwerp-areas van die brugdek, as 'n voorlopige benadering vir die negatiefste effekte van normale verkeers-belasting gebruik kan word. Dit was egter verder gevind dat vir 'n groot aantal sekondêre buig-effkte, die versameling standaard aanwendings-patrone nie as 'n goeie benadering vir die negatiefste waardes dien nie.