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ABSTRACT With Petro-Canada's extensive involvement in oil and gas development off Canada's East Coast, the company made a strategic decision to establish and locate a new Strategic Business Unit (SBU) in eastern Canada to manage all of its East Coast offshore development and operations activities. This entity has established itself firmly as a major player in Canada's East Coast offshore oil and gas industry. With the establishment of the East Coast SBU, Petro-Canada East Coast management believed that real value was to be gained in designing and implementing a dedicated, structured Quality Management System with the objective being to help effectively manage its East Coast activities and to continually improve the quality of work. This paper outlines the main features of Petro-Canada East Coast's Quality Management System. INTRODUCTION Petro-Canada is a major player off Canada's East Coast (Figure. 1) with interests in every major Grand Banks discovery to date. The company holds significant interests in the Hibernia field (the first Grand Banks development) which has been producing oil since 1997, and is the operator of the Terra Nova field development which achieved first oil early in 2002. It also holds interests in the White Rose development, which is currently in project phase, and in the Hebron/Ben Nevis discovery. Outside the Grand Banks, Petro-Canada is executing a 2003 exploratory drilling program in the Flemish Pass Basin (deepwater) and also has extensive land position in both explored and under-explored regions off Newfoundland and Nova Scotia. With the establishment of the Petro-Canada East Coast Strategic Business Unit in the late 1990's, Petro-Canada East Coast management believed that real value was to be gained in designing and implementing a dedicated, structured Quality Management System with the objective being to help effectively manage its East Coast activities and to continually improve the quality of work.
- North America > Canada > Newfoundland and Labrador > Newfoundland > North Atlantic Ocean > Atlantic Margin Basin > Grand Banks Basin > Jeanne d'Arc Basin > Terra Nova Field (0.99)
- North America > Canada > Newfoundland and Labrador > Newfoundland > North Atlantic Ocean > Atlantic Margin Basin > Grand Banks Basin > Jeanne d'Arc Basin > Hibernia Field > Hibernia Formation (0.99)
- North America > Canada > Newfoundland and Labrador > Newfoundland > North Atlantic Ocean > Atlantic Margin Basin > Grand Banks Basin > Jeanne d'Arc Basin > Hibernia Field > Avalon Formation (0.99)
- North America > Canada > Newfoundland and Labrador > Newfoundland > North Atlantic Ocean > Atlantic Margin Basin > Grand Banks Basin > Flemish Pass Basin (0.99)
ABSTRACT For an offshore structure located in a seismic area, it is very important to clarify the dynamic response characteristics due to seismic forces. Especially, nonlinear dynamic response evaluations of an offshore platform subjected to severe seismic forces are examined. The dynamic response analyses are carried out using the increment method in the time domain. Taking into accounts uncertain parameters with respect to the strength of materials of the structure and the dynamic loads such as wave and seismic forces, it is very important to clarify these uncertain parameter contributions on the responses in order to make the nonlinear dynamic responses to the reliable evaluations. The examination is carried out with the Monte Carlo simulation. It is shown that since the uncertain parameter effects on the response evaluations play the important contribution on the nonlinear response, it is very essential to clarify these effects on the nonlinear maximum dynamic response quantities. INTRODUCTION While the wave force is one of the most important loads on an offshore structure, the seismic force plays important roles on the reliable design of the offshore structure located in a seismic area. If the structure is subjected to severe seismic forces, it is necessary to make the dynamic response characteristics clearly for the reliable design of the structures. Taking into accounts a stochastic property of the wave force and the seismic force, the response quantity such as the maximum response can be evaluated using a random vibration analysis by means of the spectral approach (Jesien 1987). For enhancing the safety of the structure subjected to severe dynamic forces, it is also necessary to examine the nonlinear dynamic response evaluations as well as the linear response ones, because these dynamic forces have generally random properties.
- Asia > Japan (0.29)
- North America > United States (0.28)
ABSTRACT The paper provides the modern techniques to analyze and evaluate the shipboard vibrations. International Guidelines for the evaluation of vibration in merchant ships, ISO6954–1984 was fully revised and replaced by a new ISO6954:2000 in 2000. Since the criteria for the severity of vibrations in the new guideline are substantially different from old ones, special attention must be paid to the selection of the appropriate methods of data analysis. The real dada measured on the navigation bridge deck of a container carrier besides typical time series including sinusoid, beating and random vibration are analyzed by several methods. The digital filtering in time domain and the narrow band Fast Fourier Transform (FFT) in frequency domain are both employed. The effects of FFT block size, frequency resolution, antileakage windows and averaging methods on the evaluated vibration levels are investigated. Based on the results of the investigations, an adequate procedure, which complies with new ISO6954, is offered. INTRODUCTION The vibration is now considered to be an important feature in the overall assessment of a ship''s qualities. The excessive shipboard vibration in an accommodation area may interfere with comfort and working efficiency of ship crews. It is essential that given time histories of vibration measurement can lead to the same conclusions as to the severity of vibration no matter who or which institute may analyze the data. The old ISO6954–1984 had been widely used over a number of years as a guideline for the evaluation of vibration in merchant ships, however, there were some confusions with respect to severity of vibrations because the term of Maximum Repetitive Value (MRV) in the old standard was not clearly defined. It was especially difficult to evaluate MRV for the random vibrations. Also the instantaneous revolution speed of propeller shaft is not constant in a strict sense.
- Asia > Japan (0.46)
- North America > United States (0.28)
- Transportation > Marine (0.48)
- Shipbuilding (0.46)
ABSTRACT The present study aims to clarify mechanical response of ground bearing coastal structure such as wave dissipating block and breakwater subjected to ocean wave. A series of cyclic loading test was conducted in 1g field, and stress condition in maritime field was simulated by means of both the cyclic loading and the oscillating water pressure loading apparatus. In this test scheme, effect of fabric anisotropy of ground beneath coastal structure on bearing capacity-lateral deformation behavior was investigated detailedly. Based on test results obtained, a countermeasure method against the ground failure was also proposed. INTRODUCTION With the development of waterfront, proper evaluation of the stability of structure-ground system has been desired in the design of coastal engineering. This requires to grasp the mechanical behavior of the system in various viewpoints. Presented herein are the fundamentals of mechanical behavior of anisotropic grounds to wave-structure interaction, which are obtained by using the soil box with the two-dimensional plane strain condition (Miura et al., 1995; Kawamura et al., 1997). In particular, an evaluation for the stability is discussed with an emphasis on geotechnical viewpoint. Fabric anisotropy of sand deposits plays an important role to evaluate bearing capacity in foundation engineering. Many researchers have quantified variation in strength of ground attributed to the difference in anisotropy (e.g. Oda and Koishikawa, 1979; Kimura et al., 1985; Tatsuoka et al., 1991). TEST APPARATUS Figure 1 shows the whole view of apparatus developed by Miura et al (1995). This setup does not require a wave channel to simulate the various stress states induced by both of wave force and oscillation of structure. The cyclic loads and oscillating water pressure which produce wave force can be given sinusoidally on a model structure through the vertical and horizontal rams and the oscillating water pressure loading equipment.
ABSTRACT In this study, the authors try to develop a compaction control technique for embankment using its apparent resistivity, This is a part of the research for applying the high-density resistivity prospecting in construction engineering. Firstly, the correlation between apparent resistivity (Ra) and air void ratio (va) was confirmed. Secondly, based on these test results, "Ra-va Method" was developed as a compaction control technique for the embankment construction using apparent resistivity. 1. INTRODUCTION High-density resistivity prospecting has recently been developed as one of prospecting methods for visualizing the ground formation. In this method, the ground formation is estimated by the resistivity distribution obtained through computer-aided optimizing analyses of the densely measured apparent resistivity of the ground. The apparent resistivity of a ground or a bedrock is different depending on its grain size, porosity, degree of saturation and so on. Therefore, this method is presently expected for lots of needs to reveal the ground conditions in the geotechnical engineering field (Matsui: 1995). The purpose of this study is to develop a new technique on quality control for embankment using the apparent resistivity, as one of the applications in the geotechnical engineering field. Generally speaking, the available indexes for compaction control of embankment are the density, air void ratio, and/or strength and deformation characteristics of soils. Among them, the density is usually used as the density ratio between data by laboratory compaction test and in-sitn RI (radio isotope) method. However, the RI method cannot be applied in such cases of gravelly to crushed stone materials for embankment and thick compaction layers for rapid execution of embankment. In this paper, the authors try to develop a compaction control technique for embankment using apparent resistivity, followed by confirming the applicability to the field embankments.
- Asia > Japan (0.29)
- North America > United States (0.28)
- Europe > Norway > Norwegian Sea (0.24)
ABSTRACT Static and dynamic properties of marine soils play an important role in the design of offshore structures just as in case of on-shore structures. Liquefaction in the marine environment may be induced by earthquake loads, storm wave loads, or a combination of the two. The paper reviews the commonly available approaches for evaluation of liquefaction potential using the cyclic stress approach and the cyclic strain approach. Estimation of wave induced pore water pressures and their dissipation, or partial dissipation, before the subsequent wave load application also needs consideration. INTRODUCTION Safe design of foundations for offshore structures needs an understanding of soil-structure interaction effects under dynamic loads. Most studies on soil properties and behavior under dynamic loads were initially conducted for the on-shore soils for earthquake type loading. However, the soils in the offshore environment may be subjected to seismic loads, storm wave loads or a combination of the two. It is well understood that the storm wave loads have altogether different characteristics compared to seismic loads. Offshore structures are designed for a combination of static and dynamic loads. In order to ensure safe design and performance of such structures, the soil properties must also be determined for these load combinations. STATIC SOIL PROPERTIES The static soil properties of marine soils are discussed here by considering four sedimentary environments in southern California; continental borderland (Bouma et al., 1972; Gershowetz et al., 1972), namely; (1) the Continental Shelf (0–100 m), (2) Basin Floor (700 to 100 m), (3) Basin Slope (100 to 800 m), and (4) Submarine Canyon Fan (700 to 800 m). These properties are listed in Table 1. may be observed in Table 1, that the shelf sediments are characterized by greater shear strengths, grain size and bulk densities, and lower water content, specific gravity, porosity and compression index.
- North America > United States > California (1.00)
- North America > Canada > British Columbia > Metro Vancouver Regional District (0.28)
- Geology > Structural Geology > Tectonics > Plate Tectonics > Earthquake (1.00)
- Geology > Sedimentary Geology > Depositional Environment (1.00)
- Energy > Oil & Gas > Upstream (1.00)
- Government > Regional Government > North America Government > United States Government (0.46)
- South America > Atlantic Basin (0.99)
- North America > Atlantic Basin (0.99)
- Europe > Atlantic Basin (0.99)
- Africa > Atlantic Basin (0.99)
A Practical Method In Evaluating Liquefaction Potential of Soils
Chen, Yie-Ruey (Department of Land Management and Development, Chang Jung Christian University) | Hsieh, Shun-Chieh (Department of Land Management and Development, Chang Jung Christian University) | Shan-Kung, Pai-Lung (Department of Land Management and Development, Chang Jung Christian University)
ABSTRACT Based on existing methods eight common parameters affecting the soil liquefaction are considered and weighted through the principal component analysis. To reduce the dimensionality of the data set, four principal components are obtained by projecting the multivariate data vectors on the space spanned by the eigenvectors. Using the available field liquefaction and non liquefaction data, the influence of various parameters in evaluation model is quantified by golden section search. The field data gathered from the Chi-Chi earthquake of Taiwan in 1999 is also used to perform the verification of evaluation model. The results reveal that the proposed method is simple and effective. INTRODUCTION Due to the liquefaction of soils, there were many ground failures with the occurrence of earthquake. Lots of damages such as landslide, ground deformation, and sand boiling were observed during the Chi-Chi earthquake of Taiwan in 1999 and numerous earthquakes in the past. Concerning the engineering practice for the land development, the establishment of appropriate evaluation method to estimate the liquefaction potential of soils could be an important task. Thus, the assessment of liquefaction potential of soils would be the important topic in the last few decades. Simplified method is one of the most often used for evaluation of liquefaction potential of soils (Seed, 1979; Seed and Idriss, 1982; Tokimatsu and Yoshimi, 1983; Shibata and Teparaksa, 1988, Tokimatsu and Uchida, 1990; Robertson et al., 1992; Stark and Olson, 1995; Olsen, 1997). Associated with engineering practical application, data obtained from the laboratory and field tests are adopted to develop the simplified methods. Basically, the data treatment in existing simplified methods can be divided into two groups: The first group includes the calculation of equivalent shear stress by means of the magnitude of earthquake and peak ground acceleration.
- North America > United States (0.69)
- Asia > Taiwan (0.45)
ABSTRACT The welding residual stress state in a thick HY-80 steel plate is evaluated using neutron diffraction. A brief review of different residual stress measurement methods is given and discussed with respect to the analysis of welded components. The measurement carried out can be used for the calibration and validation of numerical welding simulation. INTRODUCTION The aim of this paper is to provide an example for the residual stress determination in a multi-pass HY-80 weld which can be used for the calibration and validation of numerical welding simulation. Residual stress plays an important role in the structural performance of a component because it can lead to early failure due to fatigue or buckling. HY-80 steel with a nominal yield stress of 552 N/mm2 (80 ksi) is mainly used for the construction of submarines. The pressure hull of a submarine is constructed by welding preformed steel plates. The welding process causes residual stresses in the component. Most techniques for the evaluation of residual stress (e.g. hole-drilling, x-ray diffraction) can only determine near surface stresses. While determination of surface stresses is satisfactory for most cases in fatigue analysis it is inadequate for buckling analysis as the throughthickness distribution is needed. Neutron diffraction provides the possibility to scan the residual strain within a component and can measure components with a thickness up to 30 mm in iron materials. RESIDUAL STRESS EVALUATION Definition Residual stresses can be defined as those stresses that remain in a material or body after the manufacturing process in the absence of external forces or thermal gradients. Residual stress measurement techniques measure strains rather than stresses in a component, and the residual stresses are then deduced using the appropriate material parameters such as Young's modulus and Poisson's ratio.
- Reservoir Description and Dynamics (0.50)
- Well Drilling (0.49)
ABSTRACT The flow dynamics in a moonpool is evaluated through analysis of experimental and numerical time series of surface elevations. Experimental results are obtained in the context of the interaction of irregular waves with the barge. The excitation of natural sloshing and piston modes is investigated as well as wave transmission in the bay. Dedicated numerical simulations of extinction tests of piston and sloshing modes are also performed, using a time domain potential flow solver. Three-dimensional effects are pointed out and a good agreement is found between experimental, numerical and analytical estimations of the moonpool natural frequencies. INTRODUCTION Recent studies on flow dynamics in moonpools of FPSOs or barges showed that 3D effects cannot be neglected, (Maisondieu & Le Boulluec 2001), and are to be investigated, especially when the bay is large compared to the size of the floating unit itself. Natural sloshing and vertical modes in the bay, which can be considered as a bottomless tank, may be excited by pressure fluctuations along the hull induced by the travelling waves or by the motions of the barge. Such water motions in the moonpool can alter the response of the floating structure and possible coupling, mostly with heave, roll and pitch motions are likely to occur. Evaluation of the flow in the bay and below is also of major interest for the design and the distribution of the aircans fixed to the upper part of the risers as tensionning floats. Decay tests of the piston and sloshing modes in the moonpool are performed and natural periods are compared to analytical solutions and experimental results. EXPERIMENTS Tests were carried out on a model of the Wellhead Barge (WHB®), which is designed with an unusually large moonpool. The experimental set-up is described in Maisondieu & Le Boulluec, 2001.
- Europe > France (0.29)
- North America > United States (0.28)
- South America > Brazil (0.28)