Sistemas Modulares de Escoramento para Estruturas de Contenção Enterradas

No presente trabalho apresentam-se estudos desenvolvidos com o objetivo de análise, conceção e dimensionamento de sistemas de escoramentos metálicos modulares e reaproveitáveis a usar como alternativa técnica e económica em estruturas de contenção periférica. O sistema concebido aplicouse a um caso concreto de uma escavação urbana executada no centro de Luanda, Angola. O projeto começou a ser estudado tendo em conta os estudos geológicos e geotécnicos do terreno em causa, e posteriormente foi estudada a solução construtiva elaborada. Feito o estudo sobre a obra que se realizou com uma parede moldada e ancoragens pré-esforçadas, foi possível, a partir dai, elaborar estudos com outro tipo de sistemas de apoio. Assim, realizaram-se estudos para sistemas de apoio com escoramento linear; colunas metálicas e por uma treliça. Posteriormente, de forma a completar, complementar e poder comparar toda a pesquisa, foram efetuados mais quatro estudos, sendo os sistemas de apoio constituídos por colunas metálicas e/ou tubos circulares ou retangulares em forma elíptica no terreno do projeto e num terreno em forma de quadrado perfeito. Através dos vários estudos foi possível comparar os resultados e perceber qual será a melhor forma de otimização para futuras obras. Foi gerado um método de escoramento, que é possível ser utilizado tendo em conta as particularidades de cada obra, constituído por perfis metálicos com dimensões standard formando elipses ou círculos, conforme a forma do terreno. De maneira a finalizar este projeto foram estudados vários tipos de ligações, quer entre perfis, quer para os perfis e a parede, como também os perfis e os apoios verticais, caso sejam necessários. Como conclusão, e de forma expedita foi analisado o custo direto que apenas abrange a quantidade de aço utilizada para cada tipo de apoio dimensionado, comparando a escavação do projeto em causa com a escavação quadrada.

Localização de Precisão Usando Redes Sem Fios Enterradas

As Redes Sem Fios Enterradas (Wireless Underground Networks - WUN) são formadas por nós que comunicam entre si através de ligações sem fios e têm como meio de propagação o solo. Os sistemas de localização mais utilizados atualmente têm desvantagens ao nível da precisão e o custo. Nesta tese é proposta uma solução de localização de precisão que recorre à utilização de redes sem fios enterradas e um algoritmo de posicionamento baseados em Wi-Fi. O objetivo é estimar a localização de objetos, utilizando dispositivos Wi-Fi de baixo custo. Os resultados experimentais obtidos demonstram que o erro de localização é inferior a 0,40 m, e que esta solução é viável para, por exemplo, localizar jogadores num campo de futebol ou localizar um objeto num campo agrícola.

Acompanhamento das Técnicas de Construção na Obra do Aproveitamento Hidroelétrico de Foz Tua

O presente trabalho foi desenvolvido na obra do Aproveitamento Hidroelétrico de Foz Tua onde a autora teve oportunidade de realizar o estágio curricular junto da equipa da Fiscalização no período de 2 de Fevereiro de 2015 a 31 de Julho de 2015. A elaboração do presente trabalho pretende transmitir conhecimentos adquiridos relacionados com a constituição de um Aproveitamento Hidroelétrico, os tipos de barragens existentes, monitorização e controlo da segurança da estrutura da Barragem, controlo de qualidade de betão e o processo construtivo de uma Barragem. A construção da Barragem do Aproveitamento Hidroelétrico de Foz Tua tem sido realizada através do método tradicional, que consiste na aplicação de betão convencional compactado por vibração interna. Ao longo deste processo, foram aplicadas diversas técnicas construtivas, nomeadamente: escavação, betonagem, refrigeração artificial, injeção de juntas e tratamento de fundações. Neste trabalho foram ainda analisados os cuidados de segurança necessários neste tipo de estruturas, tendo como base o Regulamento de Segurança de Barragens. Este regulamento define as regras a seguir durante a execução da barragem e a monotorização que deve ser efetuada à mesma, permitindo assim o controlo da segurança da estrutura na sua construção e vida útil. É necessário ainda existir um controlo da qualidade, produção e aplicação do betão na estrutura de modo a aumentar a segurança, qualidade e durabilidade da mesma.

Aplicação do FMEA na avaliação de risco de taludes e muros de contenção tradicionais em alvenaria de pedra

Ao longo das últimas décadas o município de Amarante tem-se deparado com inúmeros problemas de instabilidade de estruturas de suporte de terras, maioritariamente instabilidade de taludes artificiais, (escavação e/ou aterro) e muros de contenção tradicionais em alvenaria de pedra. A unidade técnica de projeto, ou UTP da Câmara Municipal de Amarante tem vindo a elaborar estudos, projetos e adjudicar as obras para repor a normalidade apos a instabilização desses elementos, contudo a frequência de ocorrência destes fenómenos e os recursos necessários para a sua resolução ultrapassam a capacidade desta unidade, levando a que muitos destes casos se arrastem durante anos antes de ser reposta a sua normalidade. Perante este panorama revelou-se necessário efetuar um estudo de forma a listar, avaliar e priorizar os vários casos de instabilidade existentes, para uma eficiente alocação dos recursos disponíveis. Esta análise pretende ainda identificar as principais causas de instabilidade destas estruturas, de forma a eliminar ou mitigar a ocorrência de futuros problemas semelhantes. Para o estudo destes elementos de contenção de terras adotou-se o método de análise de risco conhecido como FMEA, “Failure Modes and Effects Analysis” ou Analise dos Modos de Falha e Efeitos, com as adaptações necessárias de forma a maximizar a confiabilidade das avaliações mediante a especificidade dos casos a avaliar e realidade da instituição.

Contact metamorphism and emplacement of the western Adamello tonalite

The geodynamic forces acting in the Earth's interior manifest themselves in a variety of ways. Volcanoes are amongst the most impressive examples in this respect, but like with an iceberg, they only represent the tip of a more extensive system hidden underground. This system consists of a source region where melt forms and accumulates, feeder connections in which magma is transported towards the surface, and different reservoirs where it is stored before it eventually erupts to form a volcano. A magma represents a mixture of melt and crystals. The latter can be extracted from the source region, or form anywhere along the path towards their final crystallization place. They will retain information of the overall plumbing system. The host rocks of an intrusion, in contrast, provide information at the emplacement level. They record the effects of thermal and mechanical forces imposed by the magma. For a better understanding of the system, both parts - magmatic and metamorphic petrology - have to be integrated. I will demonstrate in my thesis that information from both is complementary. It is an iterative process, using constraints from one field to better constrain the other. Reading the history of the host rocks is not always straightforward. This is shown in chapter two, where a model for the formation of clustered garnets observed in the contact aureole is proposed. Fragments of garnets, older than the intrusive rocks are overgrown by garnet crystallizing due to the reheating during emplacement of the adjacent pluton. The formation of the clusters is therefore not a single event as generally assumed but the result of a two-stage process, namely the alteration of the old grains and the overgrowth and amalgamation of new garnet rims. This makes an important difference when applying petrological methods such as thermobarometry, geochronology or grain size distributions. The thermal conditions in the aureole are a strong function of the emplacement style of the pluton. therefore it is necessary to understand the pluton before drawing conclusions about its aureole. A study investigating the intrusive rocks by means of field, geochemical, geochronologi- cal and structural methods is presented in chapter three. This provided important information about the assembly of the intrusion, but also new insights on the nature of large, homogeneous plutons and the structure of the plumbing system in general. The incremental nature of the emplacement of the Western Adamello tonalité is documented, and the existence of an intermediate reservoir beneath homogeneous plutons is proposed. In chapter four it is demonstrated that information extracted from the host rock provides further constraints on the emplacement process of the intrusion. The temperatures obtain by combining field observations with phase petrology modeling are used together with thermal models to constrain the magmatic activity in the immediate intrusion. Instead of using the thermal models to control the petrology result, the inverse is done. The model parameters were changed until a match with the aureole temperatures was obtained. It is shown, that only a few combinations give a positive match and that temperature estimates from the aureole can constrain the frequency of ancient magmatic systems. In the fifth chapter, the Anisotropy of Magnetic Susceptibility of intrusive rocks is compared to 3D tomography. The obtained signal is a function of the shape and distribution of ferromagnetic grains, and is often used to infer flow directions of magma. It turns out that the signal is dominated by the shape of the magnetic crystals, and where they form tight clusters, also by their distribution. This is in good agreement with the predictions made in the theoretical and experimental literature. In the sixth chapter arguments for partial melting of host rock carbonates are presented. While at first very surprising, this is to be expected when considering the prior results from the intrusive study and experiments from the literature. Partial melting is documented by compelling microstructures, geochemical and structural data. The necessary conditions are far from extreme and this process might be more frequent than previously thought. The carbonate melt is highly mobile and can move along grain boundaries, infiltrating other rocks and ultimately alter the existing mineral assemblage. Finally, a mineralogical curiosity is presented in chapter seven. The mineral assemblage magne§site and calcite is in apparent equilibrium. It is well known that these two carbonates are not stable together in the system Ca0-Mg0-Fe0-C02. Indeed, magnesite and calcite should react to dolomite during metamorphism. The presented explanation for this '"forbidden" assemblage is, that a calcite melt infiltrated the magnesite bearing rock along grain boundaries and caused the peculiar microstructure. This is supported by isotopie disequilibrium between calcite and magnesite. A further implication of partially molten carbonates is, that the host rock drastically looses its strength so that its physical properties may be comparable to the ones of the intrusive rocks. This contrasting behavior of the host rock may ease the emplacement of the intrusion. We see that the circle closes and the iterative process of better constraining the emplacement could start again. - La Terre est en perpétuel mouvement et les forces tectoniques associées à ces mouvements se manifestent sous différentes formes. Les volcans en sont l'un des exemples les plus impressionnants, mais comme les icebergs, les laves émises en surfaces ne représentent que la pointe d'un vaste système caché dans les profondeurs. Ce système est constitué d'une région source, région où la roche source fond et produit le magma ; ce magma peut s'accumuler dans cette région source ou être transporté à travers différents conduits dans des réservoirs où le magma est stocké. Ce magma peut cristalliser in situ et produire des roches plutoniques ou alors être émis en surface. Un magma représente un mélange entre un liquide et des cristaux. Ces cristaux peuvent être extraits de la source ou se former tout au long du chemin jusqu'à l'endroit final de cristallisation. L'étude de ces cristaux peut ainsi donner des informations sur l'ensemble du système magmatique. Au contraire, les roches encaissantes fournissent des informations sur le niveau d'emplacement de l'intrusion. En effet ces roches enregistrent les effets thermiques et mécaniques imposés par le magma. Pour une meilleure compréhension du système, les deux parties, magmatique et métamorphique, doivent être intégrées. Cette thèse a pour but de montrer que les informations issues de l'étude des roches magmatiques et des roches encaissantes sont complémentaires. C'est un processus itératif qui utilise les contraintes d'un domaine pour améliorer la compréhension de l'autre. Comprendre l'histoire des roches encaissantes n'est pas toujours aisé. Ceci est démontré dans le chapitre deux, où un modèle de formation des grenats observés sous forme d'agrégats dans l'auréole de contact est proposé. Des fragments de grenats plus vieux que les roches intru- sives montrent une zone de surcroissance générée par l'apport thermique produit par la mise en place du pluton adjacent. La formation des agrégats de grenats n'est donc pas le résultat d'un seul événement, comme on le décrit habituellement, mais d'un processus en deux phases, soit l'altération de vieux grains engendrant une fracturation de ces grenats, puis la formation de zone de surcroissance autour de ces différents fragments expliquant la texture en agrégats observée. Cette interprétation en deux phases est importante, car elle engendre des différences notables lorsque l'on applique des méthodes pétrologiques comme la thermobarométrie, la géochronologie ou encore lorsque l'on étudie la distribution relative de la taille des grains. Les conditions thermales dans l'auréole de contact dépendent fortement du mode d'emplacement de l'intrusion et c'est pourquoi il est nécessaire de d'abord comprendre le pluton avant de faire des conclusions sur son auréole de contact. Une étude de terrain des roches intrusives ainsi qu'une étude géochimique, géochronologique et structurale est présente dans le troisième chapitre. Cette étude apporte des informations importantes sur la formation de l'intrusion mais également de nouvelles connaissances sur la nature de grands plutons homogènes et la structure de système magmatique en général. L'emplacement incrémental est mis en évidence et l'existence d'un réservoir intermédiaire en-dessous des plutons homogènes est proposé. Le quatrième chapitre de cette thèse illustre comment utiliser l'information extraite des roches encaissantes pour expliquer la mise en place de l'intrusion. Les températures obtenues par la combinaison des observations de terrain et l'assemblage métamorphique sont utilisées avec des modèles thermiques pour contraindre l'activité magmatique au contact directe de cette auréole. Au lieu d'utiliser le modèle thermique pour vérifier le résultat pétrologique, une approche inverse a été choisie. Les paramètres du modèle ont été changés jusqu'à ce qu'on obtienne une correspondance avec les températures observées dans l'auréole de contact. Ceci montre qu'il y a peu de combinaison qui peuvent expliquer les températures et qu'on peut contraindre la fréquence de l'activité magmatique d'un ancien système magmatique de cette manière. Dans le cinquième chapitre, les processus contrôlant l'anisotropie de la susceptibilité magnétique des roches intrusives sont expliqués à l'aide d'images de la distribution des minéraux dans les roches obtenues par tomographie 3D. Le signal associé à l'anisotropie de la susceptibilité magnétique est une fonction de la forme et de la distribution des grains ferromagnétiques. Ce signal est fréquemment utilisé pour déterminer la direction de mouvement d'un magma. En accord avec d'autres études de la littérature, les résultats montrent que le signal est dominé par la forme des cristaux magnétiques, ainsi que par la distribution des agglomérats de ces minéraux dans la roche. Dans le sixième chapitre, une étude associée à la fusion partielle de carbonates dans les roches encaissantes est présentée. Si la présence de liquides carbonatés dans les auréoles de contact a été proposée sur la base d'expériences de laboratoire, notre étude démontre clairement leur existence dans la nature. La fusion partielle est documentée par des microstructures caractéristiques pour la présence de liquides ainsi que par des données géochimiques et structurales. Les conditions nécessaires sont loin d'être extrêmes et ce processus pourrait être plus fréquent qu'attendu. Les liquides carbonatés sont très mobiles et peuvent circuler le long des limites de grain avant d'infiltrer d'autres roches en produisant une modification de leurs assemblages minéralogiques. Finalement, une curiosité minéralogique est présentée dans le chapitre sept. L'assemblage de minéraux de magnésite et de calcite en équilibre apparent est observé. Il est bien connu que ces deux carbonates ne sont pas stables ensemble dans le système CaO-MgO-FeO-CO.,. En effet, la magnésite et la calcite devraient réagir et produire de la dolomite pendant le métamorphisme. L'explication présentée pour cet assemblage à priori « interdit » est que un liquide carbonaté provenant des roches adjacentes infiltre cette roche et est responsable pour cette microstructure. Une autre implication associée à la présence de carbonates fondus est que la roche encaissante montre une diminution drastique de sa résistance et que les propriétés physiques de cette roche deviennent comparables à celles de la roche intrusive. Cette modification des propriétés rhéologiques des roches encaissantes peut faciliter la mise en place des roches intrusives. Ces différentes études démontrent bien le processus itératif utilisé et l'intérêt d'étudier aussi bien les roches intrusives que les roches encaissantes pour la compréhension des mécanismes de mise en place des magmas au sein de la croûte terrestre.

Brock University Tower

The original Master Plan of 1964 called for the campus to stretch out 1 1/4 miles across the escarpment with arts buildings west of the tower and science buildings to the east. This plan laid out the development of Brock for the next 10 or 11 years by which time enrollment was expected to be near 8000 students. Pictured here is the tower and main entrance to the university. To the left is a planned administration building. The original plans also called for a miniature canal running between the boulevard at the entrance which would then pass through an underground system and open up into a waterfall at the brink of the escarpment behind the tower.

Rick Bell Family fonds, 1874-1875, 1879, 1884, 1886, 1888-1889, 1896, 1898, 1909-1910, 1939, 1945, n.d.

Lewis Tyrell married Jane Gains on August 31, 1849 in Culpeper Court House, Virginia. Jane Gains was a spinster. Lewis Tyrell died September 25, 1908 at his late residence, Vine St. and Welland Ave., St. Catharines, Ont. at the age of 81 years, 5 months. Jane Tyrell died March 1, 1886, age 64 years. Their son? William C. Tyrell died January 15, 1898, by accident in Albany, NY, age 33 years, 3 months. John William Taylor married Susan Jones were married in St. Catharines, Ont. on August 10, 1851 by William Wilkinson, a Baptist minister. On August 9, 1894 Charles Henry Bell (1871-1916), son of Stephen (1835?-1876) and Susan Bell, married Mary E. Tyrell (b. 1869?) daughter of Lewis and Alice Tyrell, in St. Catharines Ontario. By 1895 the Bell’s were living in Erie, Pennsylvania where children Delbert Otto (b. 1895) and Edna Beatrice (b. 1897) were born. By 1897 the family was back in St. Catharines where children Lewis Tyrell (b. 1899), Gertrude Cora (b. 1901), Bessie Jane (b. 1902), Charles Henry (b. 1906), Richard Nelson (b. 1911) and William Willoughby (b. 1912) were born. Charles Henry Bell operated a coal and ice business on Geneva Street. In the 1901 Census for St. Catharines, the Bell family includes the lodger Charles Henry Hall. Charles Henry Hall was born ca. 1824 in Maryland, he died in St. Catharines on November 11, 1916 at the age of 92. On October 24, 1889 Charles Hall married Susan Bell (1829-1898). The 1911 Census of Canada records Charles Henry Hall residing in the same household as Charles Henry and Mary Bell. The relationship to the householder is step-father. It is likely that after Stephen Bell’s death in 1876, his widow, Susan Bell married Hall. In 1939, Richard Nelson Bell, son of Charles Henry and Mary Tyrell Bell, married Iris Sloman. Iris (b. 22 May 1912 in Biddulph Township, Middlesex, Ontario) was the daughter of Albert (son of Joseph b. 1870 and Elizabeth Sloman, b. 1872) and Josie (Josephine Ellen) Butler Sloman of London, Ont. Josie (b. 1891) was the daughter of Everett Richard and Elizabeth McCarthy (or McCarty) Butler, of Lucan Village, Middlesex North. According to the 1911 Census of Canada, Albert, a Methodist, was a porter on the railroad. His wife, Josephine, was a Roman Catholic. Residing with Albert and Josie were Sanford and Sadie Butler and Sidney Sloman, likely siblings of Albert and Josephine. The Butler family is descended from Peter Butler, a former slave, who had settled in the Wilberforce Colony in the 1830s. Rick Bell b. 1949 in Niagara Falls, Ont. is the son of Richard Nelson Bell. In 1979, after working seven years as an orderly at the St. Catharines General Hospital while also attending night school at Niagara College, Rick Bell was hired by the Thorold Fire Dept. He became the first Black professional firefighter in Niagara. He is a founding member of the St. Catharines Junior Symphony; attended the Banff School of Fine Arts in 1966 and also performed with the Lincoln & Welland Regimental Band and several other popular local groups. Upon the discovery of this rich archive in his mothers’ attic he became passionate about sharing his Black ancestry and the contributions of fugitive slaves to the heritage Niagara with local school children. He currently resides in London, Ont.

William Still's Boarding House advertisement [n.d.]

Original advertisement for William Still's Boarding House, No. 832 South Street, below 9th, south side Philad'a [sic]. Not dated. The advertisement includes handwritten marginalia, possibly by William Still, on the left-hand side referring to St. Catharines. There is a small embossed stamp on the upper left-hand corner of the advertisement. This item was in the possession of the Rick Bell Family of St. Catharines.Handwritten marginalia (original spelling and punctuation): "Do remember me very kindly to all my enquiring friends _ I but seldom hear of late from St. Catherines" The street number printed in the original advertisement (374) has been crossed out in black ink and a handwritten "832" has been inserted. William Still was an African-American abolitionist from Philadelphia and clerk of the Anti-Slavery Society who by his own account assisted 649 slaves receive freedom. He kept records on fugitive slaves so their relatives could find them later. In 1872, he published his records in a book entitled, The Underground Railroad. Source: William Still Underground Railroad Foundation: http://www.undergroundrr.com/foundation/about.htm

W.W. Tyrrill receipt, June 1888

A receipt from W.W. Tyrrill, of St. Catharines, Ontario dated June 2, 1888, for a ladies Swiss watch priced at $11.00. The receipt is a rental agreement which specifies the terms of a fee payment schedule. Information on the receipt indicates Mr. Tyrrill sold watches, jewelry, silver plated goods, albums and Bibles. He is also listed as an agent for pianos, organs and Singer sewing machines. This receipt was in the possession of Iris Sloman Bell, of St. Catharines. Relatives of the Sloman Bell families include former Black slaves from the United States who settled in southern Ontario.There are various spellings of the Tyrrill name within the Bell family archive. Other forms of the name include Tyrell, Tyrrell, and Terrell.

Bell Family Bible, Deaths, 1862-1916

A single page from the Deaths section of the Bell Family Bible listing the names and dates of death for various members of the family.The handwritten entries appear to read as follows: "John William Taylor, died April 30th Anne Domini 1862; aged 52 years. Jess J Bell died April 11th 1872 O Mary Franices Bell died August 20th 1872. Mrs. Susan Hall. Died May, 24th, 1898 Born January 1st 1829 age. 69 William B Bell died March 19th 1897 Richard Jones died June 6th 1912 Mastam Jone died Charles H. Hall died November 11th 1916."

Letter which contains a report to George Rykert of Friends of the Port Dalhousie Thorold Railway

Letter which contains a report to George Rykert of Friends of the Port Dalhousie Thorold Railway. In this unsigned letter regarding contracts for the railway, it is suggested that the quantity of the excavation could have been done at 25 cents less per yard, July 23, 1855.

Letter sent to S.D. Woodruff from Francis Lalor

Letter sent to S.D. Woodruff from Francis Lalor regarding the last estimate of work. Mr. Lalor points out some additional work that was done, including: cart-road, culvert excavation and ditching, Mar. 29, 1855.

Niagara Falls Handbill Collection, 1838-1886, n.d. (non-inclusive)

According to legend, the Burning Springs were discovered by early natives in the Niagara Peninsula. Bridgewater Mills was built on the site of the spring. During the excavation of the factory; workmen uncovered the spring. Samuel Street and Thomas Clark recognized the potential of this as a tourist attraction so they built a wooden shelter over the spring. The spring was covered with a barrel with a pipe protruding from it. This became the first tourist attraction at Niagara. The Cave of the Winds was a cavern located behind the Bridal Veil Fall. It was originally named the Aeolus Cave. In 1920, a sudden rock fall from the ceiling killed 3 tourists. The cave was destroyed in 1955 as it was deemed dangerous. The captain of the Maid of the Mist was usually a farmer who owned the land where the ship docked. In 1846, the first steam powered Maid of the Mist was launched. By 1848, the first suspension bridge was built over the gorge and the main purpose of the Maid of the Mist was no longer to carry people who needed to travel, but now the focus was on people who wanted to view the Falls at close range. Source: http://www.niagarafrontier.com/burningsprings.html http://www.niagarafrontier.com/winds.html http://reservationsystems.com/niagara_daredevils/maid_of_the_mist.html

Letter to S.D. Woodruff from Fred Holmes

Letter to S.D. Woodruff from Fred Holmes stating that Edward Henderson has completed the excavation of section 1 on the Marshville tap drain, June 30, 1856.

Letter to S.D. Woodruff from Fred Holmes

Letter to S.D. Woodruff from Fred Holmes which states that the excavation of the Marshville tap ditch is finished. The contractors have collected their contracts except Henshall and Brown who have to move some more dirt, Sept. 24, 1856.