The paper investigates the influence of backfill soil, foundation soil, and horizontal joint vertical compressibility on the magnitude of vertical loads developed in steel-reinforced soil concrete panel retaining walls at the end of construction. Measurements of toe loads recorded from instrumented field walls are reviewed and demonstrate that vertical toe loads can be much larger than the self-weight of the facing. In extreme cases, these loads can result in panel-to-panel contact leading to concrete spalling at the front of the wall. Vertical loads in excess of panel self-weight have been ascribed to relative movement between the backfill soil and the panels that can develop panel-soil interface shear and downdrag loads at the connections between the panels and the steel-reinforcement elements. A two-dimensional finite-element model is developed to systematically investigate the influence of backfill soil, foundation soil, bearing pad stiffness, and panel-soil interaction on vertical loads in the panel facing. The results show that an appropriately selected number and type of compressible bearing pads can be effective in reducing vertical compression loads in these structures and at the same time ensure an acceptable vertical gap between concrete panels. The parametric analyses have been restricted to a single wall height (16.7 m) and embedment depth of 1.5 m, matching a well-documented field case. However, the observations reported in the paper are applicable to other similar structures. The general numerical approach can be used by engineers to optimize the design of the bearing pads for similar steel-reinforced soil wall structures using available commercial finiteelement model packages together with simple constitutive models.

Este trabalho avalia o comportamento a compressão de duas microestacas (MC1 e MC2), por meio de prova de carga estática lenta a compressão. As microestacas têm como armadura principal uma camisa metálica de aço API-N80, diâmetro nominal de 0,30 m e comprimento aproximado de 20 m. Foram executadas no Campo Experimental III da Unicamp onde o solo superficial é argiloso, poroso e colapsível. Nenhum dos ensaios alcançou ruptura nítida, sendo que na MC1 a carga máxima foi 2210 kN e na MC2 2470 kN e os recalques 24 mm e 26 mm, respectivamente. Dessa forma, a carga de ruptura foi estimada pelo critério de Van der Veen modificado por Aoki (1976) e comparada com estimativas dadas pelos métodos semiempíricos Lizzi (1982), Bustamante e Doix (1985) e FHWA (2005). Concluiu-se que o primeiro foi mais conservador e esses dois últimos resultaram em valores mais condizentes.

En la práctica de la ingeniería geotécnica es común el empleo de fundaciones por pilas cargadas transversalmente en la parte superior. Frecuentemente este tipo de fundación es ejecutada en suelos de alta porosidad y colapsables, comunes en varias regiones de Brasil. Debido a la poca información disponible en la literatura, se realizaron dos pruebas de carga con cargamento transversal en una pila (diám. 0,8 m; prof. 9,0m; diám. base 1,60m). Se realizó una prueba de carga estando el suelo en su condición de humedad natural y otra después de la previa inundación. Fueron obtenidas las curvas carga x desplazamiento horizontal y los coeficientes de reacción horizontal. Los resultados permitieron verificar la aplicabilidad de fórmulas teóricas de previsión de comportamiento, así como proponer parámetros a ser utilizados para el suelo. Previo a la realización de las pruebas de carga fueron realizados ensayos de laboratorio y campo para la investigación del subsuelo.

The methodologies used to calculate piled raft foundations are normally more complex than conventional foundations due to the large number of variables involved in the problem. In the conventional block, the interaction variables considered are only between the pile and the soil. In the piled raft, all the interaction effects must be considered, as follows: plate-soil, plate-piles and piles-soil, simultaneously. The Finite Element Method (FEM) has proven to be a useful tool in analyzing these types of problems. This study aims at assessing the behavior of piled rafts using the Cesar-LCPC numerical tool, version 4.0, which is based on the finite element method. Literature cases of rafts supported by 9, 15 and 16 piles were analyzed. The results obtained were compared with analysis methods presented in the bibliography. The following parameters were assessed: relative spacing (S/D), relative length (L/D), relative stiffness between piles and the soil (KPS), and settlement of piles and the raft. The spacing between piles has a significant influence on load distribution between piles and the raft. Very small spacing provides stiffness to the foundation, which then functions as a conventional pile foundation, in which only the piles absorb the load from the superstructure. The larger the L/D ratio, the lower the settlement and for a given modulus of elasticity of the pile, the increase in relative stiffness (KPS) causes an increase in settlement. In all analyses, the data obtained corroborated the results presented by other methods published in the literature.

Foundation engineering has continually sought to understand the behavior of piles subjected to loads and their influence on the overall structural behavior. Recently, more load tests are being performed in construction due to the recommendations of the NBR6122/2010 Brazilian code. The available literature offers few reports on pile behavior in a faulty foundation. Therefore, the present study assessed the behavior of a single pile with and without a defect: 5 m long, small-diameter (f = 0.25 m) bored piles were embedded in diabase soil (porous, lateritic and unsaturated) at Experimental Site II (Unicamp). The piles behavior were compared by laboratory tests, numerical analysis using the finite element software LCPC Cesar v.4.07 and experimental results from slow maintained load (SML) tests. Strain gauge instruments were installed at the top and tip of each pile. As predicted by the numerical analyses, when subjected to the first stage of the pile load test, the defective region of the pile failed structurally; however, the pile was still able to resist or "absorb" loading. Factors related to the loading ratio of the foundation, the total and differential displacements and the rotation of the top block were examined. The results obtained in the two analyses (numerical and in situ) were satisfactory and showed significant agreement, providing greater understanding of the complex behavior of this foundation system.

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Abstract. The process of learning the discipline of human anatomy is complex IntroduçãoO processo de ensino-aprendizagem tem sofrido várias mudanças importantes ao decorrer da história. Antigamente o professor tinha a tarefa árdua e cansativa de ensinar todo conteúdo para seus alunos, pois o professor era o detentor do conhecimento e as metodologias de aprendizagem eram baseadas no comportamento do aluno diante aos conteúdos que o professor lecionasse. Muitas vezes, esses conteúdos eram complexos, numerosos e possuíam várias nuances difíceis de serem compreendidas. Além disso, os conteúdos eram disponibilizados para os alunos em meios tradicionais através de livros

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