Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Terrain attributes control many hydrological, geomorphological and pedological processes, these processes influence the solar radiation, rainfall, runoff, evapotranspiration, soil moisture and the distribution of vegetation. In this way, the terrain attributes were extracted from MDE's high resolution (0.5 m) and accuracy to explain the differentiation of the soils of northeast region in the Rio Grande do Sul State, Brazil; also, to assess the accuracy of an MDS generated and soil maps obtained by the traditional soil survey, using the Kappa index, the overall accuracy, the user accuracy and correctness of the producer. Four representative catenas soils were studied of the landscape of the northeast region in the Rio Grande do Sul State. Terrain attributes analyzed by multivariate techniques showed to be effective in the differentiation of the soil, especially elevation, slope, the moisture content of the soil and the LS factor. The accuracy of the MDS was classified as excellent. The attributes of slope upstream slope, moisture content of the soil, elevation, LS factor and plane curvature in the / Os atributos do terreno controlam muitos processos hidrológicos, geomorfológicos e pedológicos, influenciando a radiação solar, precipitação pluvial, o escoamento superficial, evapotranspiração, umidade do solo e a distribuição da vegetação. Dessa maneira, atributos do terreno foram extraídos de MDE s de alta resolução (0,5 m) e exatidão para explicar a diferenciação de solos da região nordeste do Estado do Rio Grande do Sul, Brasil; também, para avaliar a acurácia entre um MDS gerado e os mapas de solos obtidos pelo método tradicional de levantamento, utilizando o índice Kappa, a exatidão global, a exatidão do usuário e a exatidão do produtor. Foram estudados solos de quatro catenas representativas da paisagem da região nordeste do Estado do Rio Grande do Sul. Os atributos do terreno analisados pelas técnicas multivariadas apresentaram-se efetivos na diferenciação dos solos, principalmente a elevação, a declividade, o índice de umidade do terreno e o fator LS. A acurácia do MDS foi classificada como excelente. Os atributos do terreno declividade a montante, declividade, índice de umidade do terreno, elevação, fator LS e curvatura planar apresentaram elevado potencial preditivo, conferindo exatidão ao MDS gerado.

The influence of the recommended LRFD Guidelines for the seismic design of highway bridges in Virginia was investigated by analyzing two existing bridges. The first bridge has prestressed concrete girders and is located in the Richmond area. The second bridge has steel girders and is located in the Bristol area. The analysis procedure for both bridges is similar. First the material and section properties were calculated. Then the bridge was modeled in RISA 3D. Live and dead load were imposed on the bridge to calculate the cracked section properties of the bridge. The period of vibration of the bridge was also calculated. After the soil class of the bridge was determined, the design response spectrum curve of the bridge was drawn. The spectral acceleration obtained from the design spectrum curve was used to calculate the equivalent earthquake loads, which were applied to the superstructure of the bridge to obtain the earthquake load effects. Live and dead loads were also applied to get the live and dead load effects. The combined effects of the dead, live and earthquake loads were compared to the interaction diagram of the columns and moment strength of the columns. The details of the bridge design were also checked with the corresponding seismic design requirement.A parametric study was performed to explore the effects of different column heights and superstructure heights in different parts of Virginia. The column longitudinal reinforcing was increased to satisfy the bridge axial loads and moments that are not within the column interaction diagram. / Master of Science