Geosynthetic tubes filled with water are considered. The tubes can be used in applications to resist rising floodwaters. They can also be used to form breakwaters and protect shores from erosion. This thesis considers single and stacked tubes resting on a rigid and deformable foundation resisting rising hydrostatic headwater. Experiments were carried out to determine the behavior of a three-tube stacked configuration resting on a sand foundation. This study was a continuation of previous work on unstacked tubes. Many tests were performed to determine the deformation and stability of the system. A geosynthetic drain was placed beneath the tubes to prevent piping. The objective was to cause failure of the system in a sliding manner and formulate a hypothesis according to the placement of the drain beneath the tubes. In order to cause a sliding failure, a strapping system was developed to try and prevent the tubes from rolling. A single tube at rest, filled with water but with no external hydrostatic pressure, was considered for analysis first. The tube rested on a rigid foundation and was assumed to be infinitely long. The friction between the tube and the foundation was neglected, and the bending stiffness of the tube was assumed to be negligible. The tube material was assumed to be inextensible. Mathematica was used to solve the system of equations and compute the unknowns. Excel was used to plot the data and observe the behavior of the tubes. An analysis was also performed on a single tube with an apron attached, resting on a rigid foundation. The apron was attached on the rising headwater side to increase stability. The assumptions for the tube at rest were also applied in this analysis. Two cases were derived and analyzed: a case where the internal hydrostatic pressure remains constant, and a case where the cross-sectional area remains constant. For the second case, the internal pressure changes as the floodwater level rises. The results from this study demonstrated that water-filled tubes, stacked or with an apron attached, can be an effective alternative method to sandbags in resisting floodwaters. / Master of Science

Geosynthetic tubes filled with a slurry-mix are considered. The mix is usually dredged from a nearby area and pumped directly into the tubes. The tubes are used in a variety of applications including breakwaters, groins, and temporary levees. This thesis considers single and stacked geosynthetic tubes resting on rigid and deformable foundations. A two-dimensional analysis is performed on the cross-section of a very long tube. The program Mathematica is utilized for the analysis. A few assumptions are made regarding the general behavior of the tube. The tube is assumed to be an inextensible membrane with no bending stiffness. To allow for a closed-form integral solution, it is assumed that no friction exists between the tubes and at the foundation. A single tube, two stacked tubes, and a 2-1 formation are studied. Both rigid and deformable foundations are considered. The deformable foundation is modeled as a tensionless Winkler foundation with normal forces proportional to the downward deflection of the ground. An external water load on one side is also investigated for a single tube and a 2-1 formation, with rigid blocks to prevent the structure from sliding along the ground. Example cross-sectional profiles are given. Results from the analysis include structure height, circumferential tension, and ground deflections. / Master of Science

The effects of basin edge slope on the dynamic response of soil deposits are assessed by using one-dimensional and two-dimensional numerical analyses. 24 basin models having trapezoidal cross section are generated to represent different geometries (basin depth, basin edge slope) and soil type. Harmonic base motions with different predominant periods (Tp) are used in the analyses. The results indicate that, for a constant basin edge slope and a constant ratio of fundamental period of site to the predominant period of base motion (Tn/Tp), the response is almost the same for different soil types, basin depths and base motions. In the sloping edge region, one-dimensional response analysis predictions are found to be conservative compared to two-dimensional analysis predictions / however beyond this region they are unconservatively biased by a factor as high as 1.5. The sloping edge region and the horizontal region of the basin are denoted by normalized distance (ND) values varying from 0 to 1 and 1 to 2 respectively. The critical region where maximum amplification observed falls in the range of ND=1.0 to ND=1.5 for basins having slopes greater than 30o. The lower boundary of the critical region is shifted towards as low as ND=0.2 for basins having slopes less than 30o. For a constant value of Tn/Tp, the increase in the amplification is smooth for basins with gentle slopes as compared to basins with steep slopes for the region where ND~1. For a basin and earthquake couple approaching to resonance state (Tn/Tp=1), the amplification for the region where ND is greater than 1 is found to be as high as 100% of that is found for the region where ND~1.

Made available in DSpace on 2016-04-28T19:33:48Z (GMT). No. of bitstreams: 1 Karlene do Socorro da Rocha Campos.pdf: 10725568 bytes, checksum: 10f11e3686df42cbc9257674a1e09cfb (MD5) Previous issue date: 2014-06-03 / This research is inserted in the fields of Linguistics and Distance Education, specifically of Online Education. It comprises the study of digital genre homepage on subjects of the graduation course Mathematics Teaching Education - Distance Mode offered by the Pontifical Catholic University of São Paulo (PUC-SP). We are based mainly on sociorhetorical conception of textual genre, in which genre is conceived as a pragmatic entity. In relation to this entity, the notions of purpose, context and action are interlinked. From this perspective, to produce a genre, users aim to achieve a certain purpose, and the success of the action that the genre conveys depends on the language choices appropriate to the communicative situation. Our hypothesis is that knowledge of the sociorhetorical organization of homepage genre helps the instructional designer in the development of educational activities that promote a positive interaction between participants of online distance learning courses and pedagogical contents, and consequently promote their involvement in the teaching and learning process. In order to test it, we examined this organization in homepages of courses offered in the 2nd half of 2012, considering the twodimensional analysis of genre model (ASKEHAVE; NIELSEN, 2004), that is founded on the sociorhetorical analysis proposed by Swales (1990), and that consider in the reading and navigating modes of digital genres, communicative purposes; functional units (rhetorical movements and links); and rhetorical strategies employed to achieve the communicative purpose. Primarily, we are based on studies of genre as social action (MILLER, 2009, 2009a [1984], 2009b [1992]; BAZERMAN, 2006 [1997]; 2009a [2004], 2009b [1994]; SWALES, 1990; BHATIA, 1993), as well as on studies of digital text genre (MARCUSCHI, 2010 [2004]; ASKEHAVE; NIELSEN, 2004) and hypertext (LEMKE, 2002; FINNEMANN, 1999). This thesis is a case study based on observation and description of a phenomenon in a specific context (MARTINS, 2008 [2006]; YIN, 1984; 2005 [2003]; TRIVIÑOS, 1987). The results obtained show that the knowledge of sociorhetorical organization of homepage genre provides an organization of pedagogical contents more oriented to interests and needs of users. Consequently, this knowledge contributes to the student engagement with the educational process / Esta pesquisa insere-se nos campos da Linguística e da Educação a Distância, mais especificamente da Educação Online, e consiste no estudo do gênero textual digital homepage em disciplinas do curso Matemática Licenciatura Modalidade a distância, oferecido pela Pontifícia Universidade Católica de São Paulo (PUC-SP). Embasamo-nos, principalmente, na concepção sociorretórica de gênero textual, em que o gênero é concebido como uma entidade pragmática, na qual se entrelaçam as noções de propósito, contexto e ação. Nessa ótica, ao produzirem um gênero, os usuários visam a atingir um determinado propósito, e o sucesso da ação que o gênero veicula depende das escolhas linguísticas adequadas à situação comunicativa. Nossa hipótese é que o conhecimento da organização sociorretórica do gênero homepage auxilia o designer instrucional a promover uma interação positiva dos participantes de cursos online a distância com o conteúdo pedagógico e, consequentemente, a promover o seu envolvimento com o processo de ensino e aprendizagem. Para testá-la, examinamos essa organização nas homepages de disciplinas oferecidas no 2º semestre de 2012, na perspectiva do modelo de análise bidimensional de gêneros (ASKEHAVE; NIELSEN, 2004), que parte da análise sociorretórica proposta por Swales (1990) e considera, nos modos de leitura e navegação dos gêneros digitais, os propósitos comunicativos; as unidades funcionais que os caracterizam (movimentos retóricos e links); as estratégias retóricas empregadas para o alcance dos propósitos comunicativos. Pautamo-nos, principalmente, em estudos de gênero como ação social (MILLER, 2009, 2009a [1984], 2009b [1992]; BAZERMAN, 2006 [1997]; 2009a [2004]; 2009b [1994]; SWALES, 1990; BHATIA, 1993); de gênero textual digital (MARCUSCHI, 2010 [2004]; ASKEHAVE; NIELSEN, 2004) e de hipertexto (LEMKE, 2002; FINNEMANN, 1999). O presente trabalho é um estudo de caso, fundado na observação e descrição de um fenômeno em contexto específico (MARTINS, 2008 [2006]; YIN, 1984; 2005 [2003]; TRIVIÑOS, 1987). Os resultados obtidos demonstram que conhecer a organização sociorretórica do gênero homepage propicia a organização de conteúdo pedagógico mais voltada aos interesses e às necessidades dos usuários. Por conseguinte, contribui para o envolvimento do aluno com o processo educacional