Faculdade de Engenharia Civil - FEC/ITEC
URI Permanente desta comunidadehttps://repositorio.ufpa.br/handle/2011/2788
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Item Acesso aberto (Open Access) Behavior prediction models and control charts for safety control of concrete dams(Universidade Federal do Pará, 2012-06) LOPES, Romulo Antonio Chaves; SANTOS, Eurípedes Pinheiro dos; VELOSO, Luís Augusto Conte MendesThis paper presents a study for improving measurement procedures on concrete dams based on the development of behavior prediction models using multiple regression and control charts. The series of displacements of the TA-2 concrete block crest of the Tucuruí Hydroelectric Power Plant, the largest Brazilian hydroelectric power plant, was taken as an example of application. The methodology that was used generated a behavior prediction model that is in good agreement with the measured displacements. Two types of control charts were tested, both of which identified the change in structural behavior of the block.Item Acesso aberto (Open Access) Caracterização da cinza de caroço de açaí residual para adição ao concreto(Universidade Federal do Pará, 2019-05) CORDEIRO, Luciana de Nazaré Pinheiro; PAES, Isaura Nazaré Lobato; SOUZA, Paulo Sérgio Lima; AZEVEDO, Caroline MenezesEnvironmental problems are a reality in today's world and are associated with urban and population growth, with little or no planning. The construction industry is one of the largest consumers of natural resources and generator of solid waste. Thus, it is interesting to think of a way to incorporate materials that are now considered waste, to the constructive process and reduce the consumption of natural materials. In this section, we have the ashes of açaí stone, residue of ceramic kilns, that today do not present an adequate destination. Thus, this research has the main objective to characterize residual ash of açaí (CCAR), in order to make possible its reuse as an input of the civil construction. In order to achieve this objective, a milling study was carried out in order to determine the optimum material processing time, characterization from the chemical, physical and mineralogical point of view, and the pozzolanic potential analysis to evaluate the residual ash reactivity. The results show that ash has physical characteristics that allow it to be used as an addition to concrete. There was a decrease in the axial compressive strength and an increase in the water absorption of concrete with additions, in relation to the reference concrete. In spite of these effects, a certain densification of the cementitious matrix was observed, probably due to the variation of the particle size that may provide greater compactness with optimization of grain packing.Item Acesso aberto (Open Access) Global stability analysis of reinforced concrete buildings using the γ z coefficient(Universidade Federal do Pará, 2017-10) VIEIRA, Vitor Vinicius dos Santos; RODRIGUES JÚNIOR, Sandoval José; VELOSO, Luís Augusto Conte MendesGlobal stability analysis is becoming increasingly important in the design of reinforced concrete buildings, especially in the slender ones, due its sensitivity to lateral displacement. The loss of stability is usually associated with the intensity of the second order effects and, in that sense, the gamma-z (γz) coefficient is an important evaluation parameter for this problem. This work aims to verify the γz efficiency as a global stability parameter based on the buckling load factors of the structures and their respective critical buckling modes. To this purpose, a comparative analysis is performed in several idealized structures, from which an approximate equation for calculating the critical load factor based on the γzcoefficient is obtained. This equation was verified by numerical analysis of Finite Elements Method models of real reinforced concrete buildings. It was concluded that the proposed equation presents satisfying results within a certain range of γz.