Three investigations were conducted on the nature of the radiance field in clear ocean water. It is important to understand the sunlight intensity below the sea surface because this leads to an understanding of how ocean creatures navigate in shallow and deep water. The nature of the radiance field is also gives an understanding of the living environment for ocean animals. Hydrolight 4.1, a simulation software developed by Curtis D. Mobley, was used to calculate the spectral radiance in clear ocean water for multiple wavelengths from the surface down through the asymptotic region. The first study found, as expected, that Raman scattering has little effect on wavelengths of light that are less than 500 nm. The effect of Raman scattering increases with increasing wavelength, and with increasing depth. The second study found the region of the water column where the radiance field is asymptotic. The third investigation found the effect of changing the mean square slope, or variance of the water-wave slope distribution. This effect is greatest near the surface and for a more truncated mean square slope integral. There are three peaks in percent difference to the ideal case, near the surface, one in the solar beam and the others near the critical angle of water.

During the Late Pliocene to Middle Pleistocene Ages, sediments of the study area were deposited in the intra-slope salt withdrawal basin where sand-prone sediments deposited as turbidite lobes and channel fills are the main reservoirs of the Northern Gulf of Mexico. The main purpose of this study was to identify and characterize these sand-prone sediments. Sequence stratigraphic analysis of well logs, biostratigraphic data, and 3-D seismic data provided a chronostratigraphic framework of the study area, within which seismic facies analysis was carried out. Each sequence was subdivided into separate seismic bodies characterized by specific amplitude, coherence of reflectors, and shape of reflectors. The descriptions of each seismic facies combined with well logs were compared with turbidite facies models to infer their geological information. Five turbidite elements were identified: depositional channel fills and overbank deposits, erosional channel fills, turbidite lobes, mud turbidite fills and sheets and hemipelagic and pelagic drapes. Depositional channel fills are usually deposited in lower parts of interpreted sequences, surrounded by shale-prone overbank deposits. The lateral variation of these turbidite elements was revealed by horizon slices, in which depositional channels are generally trending NE-SW or NNE-SSW with elongated sinuous forms. Well logs indicate that depositional channel fills usually consist of bell or cylinder type sand-prone sediments. Turbidite lobe was found only in the 1.1-0.8 Ma sequence, in which it laps out onto the underlying sequence boundary and shows high-amplitude and a high-coherence of mound shape. This facies is interpreted as sand-prone, but wells available penetrated only the marginal parts of this facies and showed poor reservoir qualities. Horizon slices could partly reveal its lapout boundary due to the limitation of vertical seismic resolution. Mud turbidite fills and sheets are the most dominant turbidite facies, which usually occurred in the upper parts of sequences and overlain by hemipelagic and pelagic drapes. Hemipelagic and pelagic drapes were deposited very widely, wrapping down the previous topography with consistent thickness throughout the basin. Erosional channel was observed only in the 0.8-0.7 Ma sequence where it cut into the underlying sequence and was filled by shale-prone sediments. Depositional channel fills and turbidite lobes are the main reservoir facies in the study area. Seismic facies analysis using vertical seismic sections and horizon slices combined with lithology data made it possible to identify and systematically describe these sand prone turbidite elements in intra-slope salt withdrawal basin.

The moved sand caused by the wave is one of the important issue in coastal engineering. Moved sand of the coastal refers that wave and current ,cause sand suspended and moved, and it also caused the change of seabed along the coast. To estimate the change of sediment and establish the mechanism of sediment is very important in coastal engineering design. The series of hydraulic model experiments in wave flume are used to observation the relationships between moved sand and incident water wave condition. In this thesis, the movable-bed model of slope 1/45¡B1/30 ,which moved sand were estimated with surveyed from images of flume glass, and use image processing technique, we can calculate actual situation of movable-bed change. We also use the braces of sensor which was new design, set braces near surf zone, obtain the change of the pore pressure under the movable-bed and analysis the relationships between moved sand and incident water wave condition.

Harvesting is typically one of the largest cost components within a plantation forest rotation. A large proportion of New Zealand’s future harvest will be on steep terrain. Currently steep terrain harvesting is characterised by lower productivity and higher cost. It also has higher levels of manual or motor manual tasks such as setting chokers or tree felling, with a corresponding higher safety risk. The utilisation of ground-based machines on steep terrain has the potential to decrease harvest costs and improve safety. There is currently a push in New Zealand to increase the operating range. This is being done with a poor understanding of the slopes on which machines are currently operating and little understanding of the new risks steeper slopes might introduce. To better understand the true range of slopes on which forest machines are operating, a digital accelerometer was attached to 22 forest machines and provided real-time measurements of slope. The evaluated machines were grouped into one of four machine types; felling (n=4), shovelling (n=5), skidder (n=9) or European (n=4). The machine types were then analysed with respect to their machine slope (actual) and terrain slope (predicted) based on a digital terrain map. Two methods of calculating terrain slope were used, method one was based on a triangular irregular network (TIN) file with method two based off a raster file. Linear regression indicated that there was a relationship between machine slope and terrain slope for all four machine types, with the exception of European based machines, using the TIN method of slope calculation. All variables showed a poor coefficient of determination with the highest adjusted R squared single variable explaining 17% of the variation. All machines operated on slopes that exceed the New Zealand approved code of practice guideline of 30% and 40% slope for wheeled and tracked machines respectively. New Zealand based machines were shown to exceed the guidelines for terrain slope much more frequently, and by a greater margin, than European based machines.

Slope instabilities have been affecting the grade slope of Provincial Trunk Highway 5 near the junction with Provincial Trunk Highway 10 in northwestern Manitoba for over 50 years. In recent years, the instabilities have resulted in significant damage to the highway pavement surface. In 2011, Manitoba Infrastructure and Transportation initiated a geotechnical investigation to gain a better understanding of the failure, identify possible failure mechanisms, and explore various remedial design alternatives in order to stabilize the slope. The site was instrumented with slope inclinometers and vibrating wire piezometers, and monitored over a period of two years. An extensive laboratory testing program was completed to compare the results of direct shear tests and torsional ring shear tests for determining the shear strength of the underlying Cretaceous clay shale. Measured values were compared with values back analyzed using limit equilibrium analysis. A coupled finite element model was used to model the expected excess porewater pressure response, and therefore the stability of the slope, during construction of a stabilization berm. It was subsequently calibrated to agree with the measured porewater pressure responses from the instrumentation. Finally, spring flood conditions were simulated to determine the effect of multiple flash flood events on the stability of the slope.

Hill slopes in wine producing regions of the South Island of New Zealand are rarely developed for viticulture despite having the capability. Viticultural development in these wine producing regions is primarily limited to flat areas despite the benefits of hill slopes that can increase productivity and variability of the grapes grown. The objective of this study is to assess the viability and development of hill slopes in the South Island of New Zealand with regards to industrial viticultural development. Site investigation in combination with background research identified five fundamental characteristics (i.e., elevation, slope angle, aspect, temperature and rainfall) that are required for proper assessment as well as industrial viticultural practices and concerns specific to the South Island. A slope angle of 15° was determined to be suitable for viticultural development as this angle is the maximum angle for machinery to work and operate safely. Additionally, this slope angle encourages the benefits that hill slopes provide and slope stability issues are limited. GIS suitability mapping demonstrates that ~0.7% of the South Island of New Zealand is viable for hill slope viticultural development using elevation, slope angle, aspect, temperature and rainfall characteristics to produce the maps. Temperature and sunlight relationships via data logger analysis support the various benefits that hill slope development provides, including increasing the number of growing degree days (GDD) by 1, increasing air and soil temperature and increasing sunlight exposure by 3,000 Lux. Overall, findings identify the extent and benefits that hill slopes may provide in major grape regions within the South Island of New Zealand.

This dissertation investigates the nature of submarine landslides along the deformation front of the northern Cascadia subduction zone. As the first slope stability analysis on the west coast of Vancouver Island, this study covers a variety of large-scale tectonic to small-scale, site-specific factors to investigate the nature of slope failure. Slope failure occurred mainly on the steep slopes of frontal ridges that were formed by compressive forces due to the subduction of the Juan de Fuca plate. Multi-beam swath bathymetry data are used to study the morphology of the whole margin and the geometry of two Holocene landslides that serve as representative examples. The overall margin stability is estimated using the critical taper theory, and a first-order limit equilibrium slope stability analysis provides threshold values for external forces to cause slope failure. The present-day pore pressure regime at different sites of the Cascadia margin is estimated from log-density data and expected ground accelerations are calculated via ground motion attenuation relationships. A comparison to threshold values derived from the limit equilibrium analysis suggests that, at present, slope stability is more sensitive to overpressure than to earthquake shaking. Differences in power spectral density derived from OBS-velocity data imply a slightly amplified ground response at the ridge crest compared to sites along the continental shelf and abyssal plain. Apart from estimating the trigger mechanisms of submarine landslides offshore Vancouver Island, a particular consideration is given to the potential link between slope failure and methane hydrate occurrence. The history of the gas hydrate stability zone (GHSZ) boundaries is investigated using information on regional sea-level history. Assuming colder ocean-bottom temperatures during the Holocene, a gradual shoaling of the BSR is inferred, which potentially could have caused hydrate melting. Pore pressure due to hydrate dissociation, as estimated by a previously developed method, varies over several orders of magnitude. Depending on sediment permeability, overpressure ratios can be comparable to threshold values. The two Holocene landslides are modeled numerically using a two-dimensional finite difference code in order to recreate the along-strike variability in ridge geometry and slide morphology observed along the northern Cascadia margin. Geometry and morphology correlate with the two prevalent slide mechanisms and model results suggest that sediment yield strength and average slide thickness are associated with the slide mechanism as well. / Graduate / 0373 / nscholz@uvic.ca

The most common way to analyze slope stability is to employ limit equilibrium (LE) theory and obtain a factor of safety (FOS). Methods of LE analysis balance the forces, and/or moments that are driving and resisting slope movement. Generally, in geotechnical engineering practice, a slope that plays host to an important structure is designed with a minimum factor of safety (FOS) of 1.5 and slope movement is monitored throughout the structure’s serviceable life. No further analysis of slope stability is completed until failure occurs when a back analysis is undertaken for the design of remedial measures. This thesis builds on current methods to demonstrate a framework for analysis that can be followed to analyze the state of a slope throughout its serviceable life. The two bridges at North Battleford, Saskatchewan (Battlefords bridges) were used as case studies for this work. In 1967, the older of the two bridges experienced a slope failure at its south abutment immediately prior to its opening to the public. The failure was remediated reactively by means of subsurface drainage, a toe berm, and river training that included diversion/spur dikes to reduce scour at the landslide toe. Since remediation, there has been no other catastrophic failure at either bridge but slow movement continues in the south abutment slope. Laboratory data and field observations from the onsite inclinometers were provided by Clifton Associates Ltd. (CAL) and Saskatchewan Ministry of Highways and Infrastructure (SMHI). The following methodology was followed to develop a framework of analysis for low FOS slopes: 1. Synthesis of data collected during previous investigations at the Battlefords bridges; 2. Detailed site characterization using existing research and terrain analysis; 3. Back analysis of the critical section through original failure using traditional limit equilibrium methods to calibrate the soil strength properties; 4. Application of the calibrated soil strength properties to the original failure after remediation; 5. Estimation of unknown soil properties using instrumentation at the site. 6. Create a model of the new bridge south abutment with the calibrated strength properties from steps 4 & 5 using the finite element method (FEM). 7. Confirmation of the mechanism of failure and assessment of the shear strain and mobilized shear strength; and, 8. Comparison of the results of FEM and LEM models and relationship between factor of safety and mobilized shear strength. The framework presented in this thesis presents a method of modeling the instability of a slope. In the absence of triaxial testing data, it presents a range of mobilized shear strengths along the shear plane.

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Made available in DSpace on 2014-06-11T19:26:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-02-04Bitstream added on 2014-06-13T18:29:47Z : No. of bitstreams: 1 benessiuti_mf_me_bauru.pdf: 4336666 bytes, checksum: b38250d3f308f9ca935e1e148d3fa7a0 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A região das nascentes do ribeirão Guaratinguetá, localizada no contraforte da Serra da Mantiqueira, Vale do Paraíba, tem sido intensamente modificada por ações antrópicas criando condições que favorecem os movimentos de massa, princiapalmente devido à supressão da mata nativa. Estas ações, somada ao aumento a intensidade de chuvas sobre uma complexa geologia da região, têm potencializado os escorregamentos translacionais, de modo que foram registradas mais de 40 ocorrências, nas chuvas do final de 2008 e início de 2009. Neste contexto, as proposta desta dissertação é de identificar os mecanismos que geram essas instabilidades através da avaliação das características geotécnicas de dois escorregamentos característicos na bacia do ribeirão Guaratinguetá. Para isso, as atividades envolveram ensaios de laboratório e de campo. No laboratório foram realizados ensaios para a caracterização completa das amostras, ensaios de sucção, para determinação das curvas características, e ensaios de cisalhamento direto, para determinação dos parâmetros de resistência. No campo, foram determinadas as propriedades hidráulicas através do permeâmetro de Guelph e a resistência à penetração dos horizontes utilizando o Penetrômetro Dinâmico de Cone. O estudo dos possíveis processos de identificação de instabilidade foi realizado a partir de retro-análises dos dois escorregamentos estudados, através do software SLOPE/W, da GeoSlope, e de simulações de cenários, através do modelo matemático Shalstab. Nestas análises, foram consideradas diferentes hipóteses relativas à presença de água no subsolo, onde foram verificados os respectivos fatores de segurança. Os resultados das retro-análises indicam coerência entre as superfícies previstas e observadas no campo, para a condição de solo saturado acima da superfície de ruptura e solo na umidade residual... / The land degradation process as consequences of deforestation and farming activities at the northem part of the Guaratinguetá creek watershed, Paraíba Valley, is compromising the environmental balance of the region traduced by increase in the numbers of shallow landslides occurring during rain seasons. In summer 2009, more than 40 shallow landslides occurred during an intense rainfall with serious consequence for the local population. In this context, the purpose of this dissertation is to understand the mechanism that triggered the soil movement based on geotechnical investigation of two landslides in the Guaratinguetá creek watershed. The geotechnical profiles of two landslides and the hydraulic parameters were determined by field tests using Dynamic Cone Penetrometer and Guelph Permeameter. In laboratory, physical and mechanical soil properties were determined. The shear strength parameters were obtained by direct shear tests on undisturbed speciments for three initial gravimetric water contents (residual, natural and saturated). The instability process was inferrred by back-analysing these two landslides using the SLOPE/W, GeoSlope, and simulating scenarios using SHALSTAB model. These analyses took into account the physical properties and the shear strength parameters of the solis for different water contents. The predicted slip surfaces were in agreement with the observed ones when the analyses considered the soil parameters above the slip surface as saturated and the soil parameters below the slip surface as in residual water content condition. The susceptibility map using SHALSTAB were then carried out for the soil parameters for satured condition. The influence of the vegetation (root strength) was inserted in the analyses by a scale factor based onn Algebra Map Technique. The validation of the applied methodology was verified by crossing the predicted unstable... (Complete abstract click electronic access below)