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Babs M Oyeneyin - One of the best experts on this subject based on the ideXlab platform.
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Analytical critical drawdown (CDD) failure model for real time sanding potential prediction based on Hoek and Brown failure Criterion
2020Co-Authors: Gbenga Folorunso Oluyemi, Babs M OyeneyinAbstract:The risks of failure in sand reservoirs and consequent sand production is now a stark reality in the upstream oil and gas industry. As a result, failure analysis of reservoir rocks for sanding potential prediction purposes has become a routine activity more than ever before. Owing to the huge economic, operational and safety implications of risks of sand failure, the efficient management of these risks for field operation optimization requires a reliable failure model, which can capture the failure processes adequately in real time. Mohr coulomb failure Criterion has been more widely applied for rock mechanics problems relating to sand failure analysis and production in the oil industry and elsewhere, and has been used as the basis or platform for more than 80% of the failure models being used in the industry today for rock failure analysis and sanding potential prediction. The major reasons for this could be attributed to: (a) simplicity in understanding and use and (b) description by a simple mathematical expression. The mathematical expression of Mohr Coulomb Criterion defines shear stress as a linear function of the normal stress, which is depictive of a linear failure envelope. In addition Mohr Coulomb is only applicable to intact rocks and cannot be applied to already failed rock. Failure envelope in petroleum formation rock has however been proved to be non-linear and as such Mohr Coulomb failure Criterion and the models based on it cannot be trusted to capture the failure processes adequately and reliably. In this study, Hoek and Brown failure Criterion has been used as a platform to develop a new time-coupled analytical failure model for the analysis of sanding potential prediction in real time. The basis for using the Hoek and Brown failure Criterion lies in its ability to capture rock failure as a non-linear process and applicability to both intact and failed rocks. This model has been tested and validated on some field data; in addition, it has been compared with another Mohr Coulombbased drawdown failure model. The results obtained from the testing and validation scheme are very encouraging and show that Hoek and Brown Criterion can indeed help overcome the inherent problems in Mohr Coulomb Criterion
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analytical critical drawdown cdd failure model for real time sanding potential prediction based on hoek and brown failure Criterion
Journal of Petroleum and Gas Engineering, 2010Co-Authors: Gbenga Folorunso Oluyemi, Babs M OyeneyinAbstract:The risks of failure in sand reservoirs and consequent sand production is now a stark reality in the upstream oil and gas industry. As a result, failure analysis of reservoir rocks for sanding potential prediction purposes has become a routine activity more than ever before. Owing to the huge economic, operational and safety implications of risks of sand failure, the efficient management of these risks for field operation optimization requires a reliable failure model, which can capture the failure processes adequately in real time. Mohr coulomb failure Criterion has been more widely applied for rock mechanics problems relating to sand failure analysis and production in the oil industry and elsewhere, and has been used as the basis or platform for more than 80% of the failure models being used in the industry today for rock failure analysis and sanding potential prediction. The major reasons for this could be attributed to: (a) Simplicity in understanding and use and (b) Description by a simple mathematical expression. The mathematical expression of Mohr Coulomb Criterion defines shear stress as a linear function of the normal stress, which is depictive of a linear failure envelope. In addition Mohr Coulomb is only applicable to intact rocks and cannot be applied to already failed rock. Failure envelope in petroleum formation rock has however been proved to be non-linear and as such Mohr Coulomb failure Criterion and the models based on it cannot be trusted to capture the failure processes adequately and reliably. In this study, Hoek and Brown failure Criterion has been used as a platform to develop a new time-coupled analytical failure model for the analysis of sanding potential prediction in real time. The basis for using the Hoek and Brown failure Criterion lies in its ability to capture rock failure as a non-linear process and applicability to both intact and failed rocks. This model has been tested and validated on some field data; in addition, it has been compared with another Mohr Coulomb-based drawdown failure model. The results obtained from the testing and validation scheme are very encouraging and show that Hoek and Brown Criterion can indeed help overcome the inherent problems in Mohr Coulomb Criterion Key words: Rock failure, sand prediction, failure criteria, critical drawdown, failure envelope, uniaxial compressive strength (UCS).
Abigail Hackston - One of the best experts on this subject based on the ideXlab platform.
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the mohr coulomb Criterion for intact rock strength and friction a re evaluation and consideration of failure under polyaxial stresses
Solid Earth, 2016Co-Authors: Abigail Hackston, E H RutterAbstract:Abstract. Darley Dale and Pennant sandstones were tested under conditions of both axisymmetric shortening and extension normal to bedding. These are the two extremes of loading under polyaxial stress conditions. Failure under generalized stress conditions can be predicted from the Mohr–Coulomb failure Criterion under axisymmetric shortening conditions, provided the best form of polyaxial failure Criterion is known. The sandstone data are best reconciled using the Mogi (1967) empirical Criterion. Fault plane orientations produced vary greatly with respect to the maximum compressive stress direction in the two loading configurations. The normals to the Mohr–Coulomb failure envelopes do not predict the orientations of the fault planes eventually produced. Frictional sliding on variously inclined saw cuts and failure surfaces produced in intact rock samples was also investigated. Friction coefficient is not affected by fault plane orientation in a given loading configuration, but friction coefficients in extension were systematically lower than in compression for both rock types. Friction data for these and other porous sandstones accord well with the Byerlee (1978) generalization about rock friction being largely independent of rock type. For engineering and geodynamic modelling purposes, the stress-state-dependent friction coefficient should be used for sandstones, but it is not known to what extent this might apply to other rock types.
Tomasz Wierzbicki - One of the best experts on this subject based on the ideXlab platform.
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strain capacity of x70 pipeline steel subjected to biaxial loading condition
ASME 2015 34th International Conference on Ocean Offshore and Arctic Engineering, 2015Co-Authors: Marcelo Paredes, Tomasz WierzbickiAbstract:In this work the tensile capacity of circumferentially pressurized cracked pipes with varying crack parameters and pipe dimensions are numerically investigated. The biaxial loading mode includes internal pressure and tensile load, which are applied in sequence. The present physics-inspired fracture model based upon the original Mohr-Coulomb Criterion enables not only the computation of global fracture response of pipe subjected to complex loading condition but also a thorough determination of the local evolving stress state around the growing cracks.Copyright © 2015 by ASME
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application of extended mohr coulomb Criterion to ductile fracture
International Journal of Fracture, 2010Co-Authors: Tomasz WierzbickiAbstract:The Mohr–Coulomb (M–C) fracture Criterion is revisited with an objective of describing ductile fracture of isotropic crack-free solids. This Criterion has been extensively used in rock and soil mechanics as it correctly accounts for the effects of hydrostatic pressure as well as the Lode angle parameter. It turns out that these two parameters, which are critical for characterizing fracture of geo-materials, also control fracture of ductile metals (Bai and Wierzbicki 2008; Xue 2007; Barsoum 2006; Wilkins et al. 1980). The local form of the M–C Criterion is transformed/extended to the spherical coordinate system, where the axes are the equivalent strain to fracture \({\bar \varepsilon_f}\) , the stress triaxiality η, and the normalized Lode angle parameter \({\bar \theta}\) . For a proportional loading, the fracture surface is shown to be an asymmetric function of \({\bar \theta}\). A detailed parametric study is performed to demonstrate the effect of model parameters on the fracture locus. It was found that the M–C fracture locus predicts almost exactly the exponential decay of the material ductility with stress triaxiality, which is in accord with theoretical analysis of Rice and Tracey (1969) and the empirical equation of Hancock and Mackenzie (1976), Johnson and Cook (1985). The M–C Criterion also predicts a form of Lode angle dependence which is close to parabolic. Test results of two materials, 2024-T351 aluminum alloy and TRIP RA-K40/70 (TRIP690) high strength steel sheets, are used to calibrate and validate the proposed M–C fracture model. Another advantage of the M–C fracture model is that it predicts uniquely the orientation of the fracture surface. It is shown that the direction cosines of the unit normal vector to the fracture surface are functions of the “friction” coefficient in the M–C Criterion. The phenomenological and physical sound M–C Criterion has a great potential to be used as an engineering tool for predicting ductile fracture.
Gbenga Folorunso Oluyemi - One of the best experts on this subject based on the ideXlab platform.
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Analytical critical drawdown (CDD) failure model for real time sanding potential prediction based on Hoek and Brown failure Criterion
2020Co-Authors: Gbenga Folorunso Oluyemi, Babs M OyeneyinAbstract:The risks of failure in sand reservoirs and consequent sand production is now a stark reality in the upstream oil and gas industry. As a result, failure analysis of reservoir rocks for sanding potential prediction purposes has become a routine activity more than ever before. Owing to the huge economic, operational and safety implications of risks of sand failure, the efficient management of these risks for field operation optimization requires a reliable failure model, which can capture the failure processes adequately in real time. Mohr coulomb failure Criterion has been more widely applied for rock mechanics problems relating to sand failure analysis and production in the oil industry and elsewhere, and has been used as the basis or platform for more than 80% of the failure models being used in the industry today for rock failure analysis and sanding potential prediction. The major reasons for this could be attributed to: (a) simplicity in understanding and use and (b) description by a simple mathematical expression. The mathematical expression of Mohr Coulomb Criterion defines shear stress as a linear function of the normal stress, which is depictive of a linear failure envelope. In addition Mohr Coulomb is only applicable to intact rocks and cannot be applied to already failed rock. Failure envelope in petroleum formation rock has however been proved to be non-linear and as such Mohr Coulomb failure Criterion and the models based on it cannot be trusted to capture the failure processes adequately and reliably. In this study, Hoek and Brown failure Criterion has been used as a platform to develop a new time-coupled analytical failure model for the analysis of sanding potential prediction in real time. The basis for using the Hoek and Brown failure Criterion lies in its ability to capture rock failure as a non-linear process and applicability to both intact and failed rocks. This model has been tested and validated on some field data; in addition, it has been compared with another Mohr Coulombbased drawdown failure model. The results obtained from the testing and validation scheme are very encouraging and show that Hoek and Brown Criterion can indeed help overcome the inherent problems in Mohr Coulomb Criterion
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analytical critical drawdown cdd failure model for real time sanding potential prediction based on hoek and brown failure Criterion
Journal of Petroleum and Gas Engineering, 2010Co-Authors: Gbenga Folorunso Oluyemi, Babs M OyeneyinAbstract:The risks of failure in sand reservoirs and consequent sand production is now a stark reality in the upstream oil and gas industry. As a result, failure analysis of reservoir rocks for sanding potential prediction purposes has become a routine activity more than ever before. Owing to the huge economic, operational and safety implications of risks of sand failure, the efficient management of these risks for field operation optimization requires a reliable failure model, which can capture the failure processes adequately in real time. Mohr coulomb failure Criterion has been more widely applied for rock mechanics problems relating to sand failure analysis and production in the oil industry and elsewhere, and has been used as the basis or platform for more than 80% of the failure models being used in the industry today for rock failure analysis and sanding potential prediction. The major reasons for this could be attributed to: (a) Simplicity in understanding and use and (b) Description by a simple mathematical expression. The mathematical expression of Mohr Coulomb Criterion defines shear stress as a linear function of the normal stress, which is depictive of a linear failure envelope. In addition Mohr Coulomb is only applicable to intact rocks and cannot be applied to already failed rock. Failure envelope in petroleum formation rock has however been proved to be non-linear and as such Mohr Coulomb failure Criterion and the models based on it cannot be trusted to capture the failure processes adequately and reliably. In this study, Hoek and Brown failure Criterion has been used as a platform to develop a new time-coupled analytical failure model for the analysis of sanding potential prediction in real time. The basis for using the Hoek and Brown failure Criterion lies in its ability to capture rock failure as a non-linear process and applicability to both intact and failed rocks. This model has been tested and validated on some field data; in addition, it has been compared with another Mohr Coulomb-based drawdown failure model. The results obtained from the testing and validation scheme are very encouraging and show that Hoek and Brown Criterion can indeed help overcome the inherent problems in Mohr Coulomb Criterion Key words: Rock failure, sand prediction, failure criteria, critical drawdown, failure envelope, uniaxial compressive strength (UCS).
Youngsuk Kim - One of the best experts on this subject based on the ideXlab platform.
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uncoupled ductile fracture Criterion considering secondary void band behaviors for failure prediction in sheet metal forming
International Journal of Mechanical Sciences, 2020Co-Authors: Hung Quach, Jinjae Kim, Ductoan Nguyen, Youngsuk KimAbstract:Abstract A new phenomenological ductile fracture Criterion that is proposed. The proposed model is associated with the micro mechanisms of void nucleation, void growth, and evolution of void coalescence. The secondary voids band and rotation of voids effect are considered in the new ductile fracture Criterion. A series of upsetting test results of aluminum 2024-T351 and TRIP RA-K40/70 steel are used to construct and compare the accuracy of fracture locus proposed by new ductile fracture Criterion, Modified Mohr-Coulomb Criterion and extend Lou-Huh Criterion. The fracture locus constructed using the proposed Criterion is close to the experimental data points over a wide stress state range from uniaxial compression to balanced biaxial tension. Then, a series of upsetting tests and square cup drawing tests are conducted with Al6014-T4 to evaluate the accuracy of the proposed Criterion. All results indicate that the proposed ductile fracture Criterion can be utilized for predicting initial fracture in sheet metal forming.