138 resultados para framtvingad slump


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Sydney Basin is located in the eastern part of Australia, Lachlan Fold Belt, and between the New England Fold Belt. From the Sydney basin at the end of the Late Carboniferous to Middle Triassic experienced back-arc spreading to the foreland basin at different stages: back-arc spreading stage (Carboniferous ), A passive thermal subsidence stage (early in the Permian Berry) and load deflection extruding stage (in Broughton Permian - Triassic). This time at the Sydney basin on the eastern side of the New England Fold Belt for the island Background of the arc. As a result, back-arc in the Permian Basin of the South Sydney basin by the back-arc spreading the eastern side of the arc and trench subduction before the impact of strong seismic activity, the development of a series of earthquake-related seismites to form various types and Seismic activity related to the deformation of soft sediment structure. Permian Basin, South Sydney's soft sediment deformation including cracks in shock-fold, liquefied vein, volcanic sand, load structure, flame Construction, pillow-like structure, spherical structure, pillow Layer structure slump, and so breccia. To which the cracks in shock-fold fibrillation is a direct result of earthquake faults and folds; pillow is a layer of sand caused by the earthquake fibrillation dehydration, the formation of the sinking; liquefied vein, Volcanic sand for the liquefaction of sand penetration of the formation of earthquake fissures formed; load structure, flame Construction, pillow-like structure, spherical structure is affected by the earthquake fibrillation in the sand, mudstone interface because of the sinking sand, mud layer formed through ; Slump structures and breccia of the earthquake was caused by the gravitational collapse or the formation of the debris flow. Fissures, earthquake-fold, liquefied vein, volcanic sand, load structure, flame Construction, pillow-like structure, spherical structure, pillow-like layer Equivalent to the original earthquake rocks the plot, and the slump structures and breccia of the plot belong to different earthquake rocks.

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The Middle Permian Wandrawandian Siltstone of the southern Sydney Basin is well exposed along the coastline from Lagoon Head in the south to North Head in the north near Ulladulla in southern New South Wales. The unit is dominated by fossiliferous siltstone and mudstone, with abundant dropstones and minor pebbly sandstone interbeds, and contains an interval of well-preserved and extensive soft-sediment deformation structures. These deformation structures occur mainly in the middle part of the cliff sections and are bounded above and below by undeformed sedimentary units of similar lithology. A wide range of soft-sediment deformation structures have been observed, including cracks, sandstone and sandy mudstone dykes, a possible sand volcano, networks of relatively small and closely connected fissure-like structures, metre-scale complex-type slump folds, flexural stratification, concave-up depressional structures, small-scale normal faults (with displacements usually <1 m), shear planes, and breccias (pseudonodules). The slumps and associated deformations are here collectively interpreted as representing a seismite deposit attributable to penecontemporaneous deformation of soft, hydroplastic sediment layers following a liquefaction triggered by seismic shocks. The timing of the inferred earthquake events appears to correspond to the onset of a major basin-wide tectonism during the Middle Permian.

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The Sydney-Bowen basin in eastern Australia is an elongate back arc-converted foreland basin system situated between the Lachlan Fold Belt in the west and the New England Fold Belt in the east. The Middle Permian Wandrawandian Siltstone at Warden Head near Ulladulla in the southern Sydney Basin is dominated by fossiliferous siltstone and mudstone, with a large amount of dropstones and minor pebbly sandstone beds. Two general types of deposits are recognized from the siltstone unit in view of the timing and mechanism of formation. One is represented by the primary deposits from offshore to subtidal environments with abundant dropstones of glacial marine origin. The second type is distinguished by secondary, soft-sediment deformational deposits and structures, and comprises three layers of mudstone dykes of seismic origin. In the latter type, metre scale, laterally extensive syn-depositional slump deformation structures occur in the middle part of the Wandrawandian Siltstone. The deformation structures vary in morphol-ogy and pattern, including large-scale complex-type folds, flexural stratification, concave-up structures, faulting of small displacements accompanied by folding and brecciation. The slumps and associated syn-sedimentary structures are attributed to penecontemporaneous deformations of soft sediments (mostly silty mud) formed as a result of mass movement of unconsolidated and/or semi-consolidated substrate following an earthquake event. The occurrence of the earthquake event deposits supports the current view that the Sydney Basin was located in a back-arc setting near the New England magmatic arc on an active continental margin during the Middle Permian.

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Australian political discourse is dominated by ahistorical hyperbole, every election defeat is a landslide, every consecutive electoral loss indicates complete political marginalisation, every poll slump is a crisis, and every struggling leader is the worst ever. Australian Labor is not faring well but we need to distinguish between the ebbs and flows of the political cycle and the fundamentals. Australian politics may be approaching a fundamental break. The political era that began in the early 1990s may be coming to an end and with it Labor's hegemonic position in Australian politics that has endured since Gough Whitlam.

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The addition of active silica potentially improves the quality of concrete due to its high reactivity and pore refinement effect. The reactivity of silica is likely related to its charge density. Variations in surface charge alter the reactivity of the material consequently affecting the properties of concrete. The present study aimed at investigating variations in the charge density of silica as a function of acid treatments using nitric or phosphoric acid and different pH values (2.0, 4.0 and 6.0). Effects on concrete properties including slump, mechanical strength, permeability and chloride corrosion were evaluated. To that end, a statistical analysis was carried out and empirical models that correlate studied parameters (pH, acid and cement) with concrete properties were established. The quality of the models was tested by variance analysis. The results revealed that the addition of silica was efficiency in improving the properties of concrete, especially the electrochemical parameters. The addition of silica treated using nitric acid at pH = 4.0 displayed the best cement performance including highest strength, reduced permeability and lowest corrosion current

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This works aims at investigating the effects of adding waste from RCBP-polyester button manufacturing to Portland cement concrete, particularly regarding its consistency and mechanic strength. The RCBP used came from a button factory located in Parnamirim, RN, Brazil. The waste was added to the concrete on different ratios: 5 %, 10 %, 15 % and 20 % of the total cement mass. A sample of concrete without the RCBP was used as reference, 1:1,33:2,45:0,50. For the mechanic strength test four samples were tested with different ages (3, 7 and 28 days old) and mixtures. Furthermore, a Slump Test was also conducted in order to verify the concrete s consistency. A tendency to a reduction in the compression resistance was noticed for all samples. For the samples with 5 % and 10 %, there was also an increase in the traction resistance during inflexion, regarding the reference concrete. In the microstructural analysis, the RBCP was observed to show an irregular and porous surface, thus explaining the consistency decrease

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From the 70`s, with the publication of the Manifesto for Environment UN Conference, held in Stockholm, in Sweden (1972), defend and improve the environment became part of our daily lives. Thus, several studies have emerged in several segments in order to reuse the waste. Some examples of waste incorporated in portland cement concrete are: rice husk ash, bagasse ash of cane sugar, powder-stone, microsilica, tire rubber, among others. This research used the residue of the mining industry Scheelite, to evaluate the incorporation of the residue composition of Portland cement concrete, replacing the natural sand. The percentage of residue were incorporated from 0% to 100%, with a variation of 10%, 11 being produced concrete mix in the ratio 1:2:3:0.60, by mass. We evaluated the following characteristics of concrete: slump test, compressive strength, tensile strength by diametral compression, water absorption, porosity and density, based on the ABNT, through tests performed in the Laboratory of Civil Construction, UFRN. The trace with the addition of 60% scheelite residue was obtained which better performance. Therefore, the use of the waste from the production of Scheelite is feasible due to the durability parameters (water absorption and porosity), sustainability, and the good results of the resistance of the concrete

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Influence of admixture on the rheological behavior of high performance self-compacting paste. This research proposes to study the influence of the specific area, mould and surface texture of admixtures on the rheological behavior of high performance self-compacting paste (HPSCP). The selected admixtures are calcareous filler and basalt filler, which are industrial residues, thus contributing to sustainable development. The paste is made up of cement, silica fume, calcareous filler or basalt filler, water and superplasticizer additive. For this study, the water/cement ratios are fixed = 0.40 L kg(-1); silica fume/cement = 0.10 kg kg(-1); the filler/cement and superplasticizer/cement ratios are determined through Marsh cone and mini-slump tests. The results show that for same filler/cement ratios, the ratios of superplasticizer to paste with calcareous filler are significantly lower than those of paste with basalt filler. The results show that the specific area, mould and surface texture of these admixtures significantly influence the rheological behavior of HPSCP.

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This research studies the influence of the pozzolanic activity of the calcareous and basalt in the resistence behavior of the compressive strength of high performance self-compacting concrete (HPSCC). The selected aditives are the calcareous filler and basalt filler, for they are industrial residues helping that way the sustainable development. The paste of this concrete type is constituted of cement, silica fume, calcareous filler or basalt filler, water and superplasticizer additive. In this research the relationships water/cement are fixed in 0,40 kg/kg, silica fume/cement of 0,10 kg/kg and the relationships filler/cement and superplasticizer/cement are determined through of Marsh́s cone and mini-slump tests. The granular skeleton is gotten from a composition between quartzous sand and brita of basalt that presents the lesser index of emptinesses. The results show that the HPSCC with the addition of calcareous filler has greater compressive strength than what the HPSCC with addition of basalt filler in the ages of 7, 28 and 63 days. It is explained by the fact that the calcareous filler presents greater index of pozzolanic activity than the basalt filler. Besides that the relation water/fine for the HPSCC with calcareous filler is 0,27 l/kg whereas the HPSCC with basalt filler is of 0,29 l/kg.

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Includes bibliography

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Pós-graduação em Engenharia Civil - FEIS

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Includes bibliography

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For six years, the global economy has been driven by the U.S. Federal Reserve’s policies of easy money. Liquidity has flowed from developed to developing economies, financing infrastructure and corporate investment and allowing consumers to indulge in credit-fuelled retail spending. Thus the effective ending of the Fed’s third round of asset purchases (QE3) at the end of October represents both a watershed and the beginning of a new stage in the world economy. The end of asset-purchases comes at a challenging time for emerging markets, with China’s economy slowing, the Euro zone struggling to avoid a recession and the Japanese economy already in recession. The unwinding of the U.S. monetary stimulus, while the European Central Bank and the Bank of Japan step up their monetary stimulus, has underpinned an appreciation by the U.S. dollar, in which most commodities are priced. An appreciated dollar makes dollar-denominated commodities more expensive to buyers, thereby creating pressure for sellers to lower their prices. Latin American markets ended the third quarter of 2014 under pressure from a stronger U.S. dollar. In this changing external context, there are many signs that a slowdown in Latin American and Caribbean (LAC) financial markets, particularly debt markets, which have been breaking issuance records for the past six years, may slowdown from now on. Commodity prices – including those of oil, base metals and some goods – are in a prolonged slump. The Bloomberg commodity price index, a benchmark of commodity investments, has fallen to a five-year low as China’s economy slows down, and with it the demand for commodities. Investment into the LAC region has decelerated, in large part because of a deceleration of mining investments. Latin American currencies have suffered depreciations, as current account deficits have widening for a number of countries. And LAC companies, having issued record amounts of foreign currency bonds may now struggle to service their debt. In October, credit-rating agency Moody’s downgraded the bonds of Brazil’s Petrobras to tow notches above speculative grade because of the impact of falling oil prices and the weaker real on its debt. Growth prospects look brighter in 2015 relative to 2014, but a strengthening U.S. dollar, uneven global growth and weakness in commodity prices are skewing the risk toward the downside for the 2015 forecasts across the region. The Institute of International Finance expects the strengthening of the dollar to have a divergent impact across the region, however, depending on trade and financial linkages. The Institute of International Finance, Capital Flows to Emerging Markets, October 2, 2014. A stronger dollar lifts U.S. purchasing power, supporting exports, growth and capital inflows in countries with close trade links to the U.S. economy. However, rising dollar financing costs will increase pressure on countries with weak external positions. Given the effects of falling oil prices and a stronger dollar, some companies in the region, having issued record amounts of foreign currency bonds, may now struggle to service their debts. Prospects of Fed rate hikes resulting in tighter global liquidity amid the rapid rise in the corporate external bond stock has indeed raised concerns over some companies. However, there is still a shortage of bonds at a global level and the region still enjoys good economic policy management for the most part, so LAC debt markets may continue to enjoy momentum despite occasional bursts of high volatility – even if not at the record levels of recent years.

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Capas carbonáticas se traduzem num dos mais importantes depósitos relacionados ao final das glaciações globais neoproterozóicas. Na região de Tangará da Serra, margem sul do Cráton Amazônico, foi descrita uma sucessão carbonática neoproterozóica de aproximadamente 20 m de espessura que inclui o topo da Formação Mirassol d'Oeste e a base da Formação Guia, respectivamente as capas dolomítica e calcária da base do Grupo Araras. A capa dolomítica é composta por dolograisntones peloidais rosados com laminação plano paralela e truncamentos de baixo ângulo, interpretados como registros de uma plataforma rasa a moderadamente profunda. A capa calcária consiste em siltitos maciços e laminados e calcários finos cristalinos com acamamento de megamarcas onduladas, interpretados como depósitos de plataforma mista moderadamente profunda dominada por ondas. Calcários finos cristalinos com laminação ondulada/marcas onduladas e leques de cristais (pseudomorfos de aragonita) intercalados com folhelhos foram interpretados como depósitos de plataforma profunda e supersaturada em CaCO3. Calcários com estruturas de escorregamento (slump), laminações convolutas e falhas sin-sedimentares caracterizam depósitos de talude e diques neptunianos, preenchidos por brechas calcárias, e camadas deformadas isoladas sugerem atividade sísmica durante a sedimentação. A sucessão carbonática de Tangará da Serra estende a ocorrência de capas carbonáticas no sul do Cráton Amazônico e corrobora com a presença de uma extensa plataforma carbonática formada durante a transgressão após a glaciação Puga correlata ao evento Marinoano.