Academic literature on the topic 'Residual fracture opening'
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Journal articles on the topic "Residual fracture opening"
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Bortolan Neto, Luiz, Aditya Khanna, and Andrei Kotousov. "A new approach to evaluate the performance of partially propped hydraulic fractures." APPEA Journal 53, no. 1 (2013): 355. http://dx.doi.org/10.1071/aj12030.
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A new approach for evaluating the performance of hydraulic fractures that are partially packed with proppant (propping agent) particles is presented. The residual opening of the partially propped fracture is determined as a function of the initial fracture geometry, the propped length of the fracture, the compressive rock stresses, the elastic properties of the rock, and the compressibility of the proppant pack. A mathematical model for fluid flow towards the fracture is developed, which incorporates the effects of the residual opening profile of the fracture and the high conductivity of the unpropped fracture length. The residual opening profile of the fracture is calculated for a particular case where the proppant pack is nearly rigid and there is no closure of the fracture faces due to the confining (compressive) stresses. A sensitivity study is performed to demonstrate the dependence of the well productivity index on the propped length of the fracture, the proppant pack permeability, and the dimensionless fracture conductivity. The sensitivity study suggests that the residual opening of a fracture has a significant impact on production, and that partially propped fractures can be more productive than fully propped fractures. Application of this new approach can lead to economic benefits.
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Zhang, Rui, Zhou Dao Lu, and Jiang Tao Yu. "Determination of Residual Fracture Toughness of Post-Fire Concrete." Advanced Materials Research 712-715 (June 2013): 1062–66. http://dx.doi.org/10.4028/www.scientific.net/amr.712-715.1062.
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Determination of double-K fracture parameter using both analytical and weight function method is carried out in present research. In calculating the cohesive fracture toughness, two situations are divided at critical load. Wedge-splitting tests with ten temperatures varying from 20oC to 600oC are implemented. The complete load-crack opening displacement curves are obtained from which the initial and critical fracture toughness could be calculated experimentally. The validation of double-K fracture model to the post-fire concrete specimens is proved. Meanwhile the weight function method agrees well with the analytical method.
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Krstić, Vladimir D. "Unified Model for Fracture of Brittle Solids." Key Engineering Materials 280-283 (February 2007): 1739–44. http://dx.doi.org/10.4028/www.scientific.net/kem.280-283.1739.
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A unified model for fracture of brittle solid based on crack opening displacement is presented. The model allows the prediction of elastic and fracture response of brittle materials containing spherical and cylindrical pores and polycrystalline solids containing anisotropic residual stresses. The analysis can also be used to predict spontaneous cracking and fracture of two phase systems possessing mismatch stresses.
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Chen, Qingyang, Anjing Tang, and Zhoudao Lu. "Toughness Calculation of Postfire Normal Concrete." Advances in Materials Science and Engineering 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/452763.
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Fracture tests of postfire normal concrete with ten temperatures up to 600°C are implemented. Residual fracture toughness using analytical method is determined. Two situations are divided at critical load when calculating the cohesive fracture toughness. The initial and critical fracture toughness could be calculated from the complete load-crack opening displacement curves. Finally, the validation of double-Kfracture model to the postfire concrete specimens is proved.
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Bian, J., and Zx Ge. "Material Test on Strain Fracture and Crack Opening Displacement Based on Digital Image Correlation Method." Archives of Civil Engineering 62, no. 3 (September 1, 2016): 3–22. http://dx.doi.org/10.1515/ace-2015-0079.
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Abstract As a machining technology, welding can cause serious accidents by overloading or operation mistakes. Through analyzing the causes of various welding accidents, we found that the major cause for damage imposed after welding parts are loaded is the fracture of materials. Therefore, studying the influence of welding residual stress on the fracture property of materials is of great significance. This paper applied the digital image correlation technique to study the fracture property of welding parts under the influence of welding residual stress. In addition, standard parts and welding parts were selected to carry out a contrast experiment. Room temperature tensile tests were performed on both standard parts and test pieces after residual stress measurement. Using displacement field and strain field data obtained through VIC-2D software, the stress intensity factor around the crack tip of each specimen under the conditions of small load was calculated and corresponding analysis was carried out.
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Dong, P., and F. W. Brust. "Welding Residual Stresses and Effects on Fracture in Pressure Vessel and Piping Components: A Millennium Review and Beyond." Journal of Pressure Vessel Technology 122, no. 3 (April 10, 2000): 329–38. http://dx.doi.org/10.1115/1.556189.
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In this paper, the recent advances in weld residual stress modeling procedures are first reviewed within the context of pressure vessel and piping applications. A typical pipe girth weld was then used as an example to highlight some of the critical issues in weld residual stress prediction, measurement, and residual stress effects on various aspects of fracture behaviors from stress intensity factor solutions for a growing crack to crack-opening displacement calculations for leak-before-break assessment. Finally, the future needs in improved fracture mechanics procedures by incorporating the rapidly expanding knowledge on weld residual stresses are summarized with respect to pressure vessel and piping applications. [S0094-9930(00)02103-X]
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Chen, Jing, and Zhoudao Lu. "Crack Extension Resistance of Normal-Strength Concrete Subjected to Elevated Temperatures." Advances in Materials Science and Engineering 2014 (2014): 1–12. http://dx.doi.org/10.1155/2014/683756.
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Determination of the residual crack extension resistance curves (KR-curves) associated with cohesive force distribution on fictitious crack zone of complete fracture process is implemented in present research. The cohesive force distributes according to bilinear softening traction-separation law proposed by Petersson. Totally ten temperatures varying from 20°C to 600°C and the specimen size of230×200×200 mm with initial-notch depth ratios 0.4 are considered. The load-crack mouth opening displacement curves (P-CMOD) of postfire specimens are obtained by wedge-splitting method from which the stress intensity factor curves (K-curves) are calculated. In each temperature, with the distribution of cohesive force along the fracture process zone, the residual fracture toughnessKR(Δa) increases with increasing crack lengthΔa, whereas theKR-curves decrease with increasing temperaturesTmfor the thermal damage induced. The stability analysis on crack propagation demonstrates that when the residualKR-curve is higher thanK-curve, the crack propagates steadily; otherwise, the crack propagates unsteadily.
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Khanna, Aditya, Luiz Bortolan Neto, and Andrei Kotousov. "Effect of residual opening on the inflow performance of a hydraulic fracture." International Journal of Engineering Science 74 (January 2014): 80–90. http://dx.doi.org/10.1016/j.ijengsci.2013.08.012.
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Lee, Jung Suk, Kwang Ho Kim, Jae Hwan Han, and Dong Il Kwon. "Evaluation of Mechanical and Fracture Characteristics Using Instrumented Indentation Technique." Materials Science Forum 539-543 (March 2007): 2210–15. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.2210.
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The material characterization on the weak points of the structural systems is essential to evaluate safety accurately. However, general material characterization methods such as uniaxial tensile test and CTOD (crack tip opening displacement) test are destructive, therefore, it cannot be applied to the system in use. To overcome this problem, the material characterization using instrumented indentation technique was developed. However, current researches on instrumented indentation technique focus on the hardness measurement. The evaluation of flow property, residual stress and fracture toughness using instrumented indentation technique is not sufficiently performed. In this paper, we introduce the evaluation method of the flow property, the residual stress near the weldment and the fracture toughness developed from damage mechanics. The algorithm of flow property evaluation, the residual stress evaluation model and the fracture toughness model by using indentation were verified comparing with the experimental results.
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Lu, Zhou Dao, and Neng You. "Determination of Double-G Fracture Parameters of Post-Fire Concrete." Advanced Materials Research 746 (August 2013): 348–51. http://dx.doi.org/10.4028/www.scientific.net/amr.746.348.
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Double-G fracture model was recently proposed based on the conception of energy release rate to describe the fracture behaviour on cracked concrete. Two fracture parameters, i.e., the initiation fracture energy releaseGIciniand the unstable fracture energy releaseGIcun, are termed to distinguish the different crack propagation stages undergoing during the whole fracture process in concrete. In present work, following the Double-G fracture model at ambient temperature, the residual Double-G fracture parameters of post-fire concrete is elaborately introduced. Totally ten temperatures varying from 20oC to 600oC and the specimens size of 230×200×200 mm with initial-notch depth ratios 0.4 were considered. Wedge-splitting method is adopted to measure the loadcrack mouth opening displacement curves (PCMOD) and double-G fracture parameters are experimentally determined.
Dissertations / Theses on the topic "Residual fracture opening"
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Bortolan, Neto Luiz. "Non-linear models for evaluating the residual opening of hydraulically stimulated fractures and its impact on well performance." Thesis, 2013. http://hdl.handle.net/2440/83808.
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Hydraulic stimulation techniques have been employed successfully over the past 60 years to enhance the productivity of oil and gas reservoirs. These techniques work by injecting a pressurised fluid into the wellbore to initiate and propagate an artificial fracture or to open a network of existing fractures. These techniques are also commonly known as hydraulic fracturing or fracking. The main objective of hydraulic stimulation is to create highly conductive pathways, which can significantly increase the permeability of the reservoir and, subsequently, improve the well productivity. An injection of small particles (usually known as propping agents or proppants) with the fracturing fluid is the most common method to prevent the stimulated fractures from full closure during the production stage because of confining stresses. To date, research has largely focused on the assessment of conditions and characteristics of fluid-driven fractures, as well as proppant transport and settlement mechanisms. The modern theory of hydraulic fractures is based on linear elastic fracture mechanics and theories of poro-elasticity, fluid flow in narrow openings and suspension flow in porous media. Despite numerous studies being carried out, few are devoted to the residual opening of hydraulic fractures, which has a significant effect on well productivity. There are many exciting potential applications and developments of hydraulic stimulation techniques for geothermal reservoirs and coal seam gas production. These all require new and more comprehensive theories, supported by analytical and numerical solutions capable of describing the non-linear effects of proppant placement and compressibility on the fracture residual opening profile and, ultimately, on the reservoir permeability and well performance. In order to address these needs and gaps, this thesis aims to develop: • a new mechanical model for predicting the mechanical response of saturated and unsaturated low-consolidated granular particles to compressive loading; • a new mathematical method and non-linear solutions for evaluating the residual aperture of fractures partially filled with unconsolidated compressible particles (proppant) and subjected to compressive loading; • a new mathematical model for evaluating the production rate of hydraulically stimulated wells taking into account the residual closure and various regions of distinct permeability along the fracture. These new models are all based on the classical theories of solid, fluid, contact, fracture, rock and soil mechanics, which provide a framework for evaluating the residual opening profiles (aperture) of hydraulically stimulated fractures, as well as the influence of the fracture residual aperture on the well performance. A number of simplifications are used to formulate the mathematical models and develop non-linear solutions. Many of these simplifications, such as two-dimensional problem geometry, plane strain conditions and linear elastic behaviour of the medium, represent a well-established foundation for analytical and numerical modelling in reservoir engineering. Accounting for other important phenomena, such as proppant flow-back and secondary cracking, is beyond the scope of this thesis but may be included in future work. The numerical results obtained within the developed models indicate that the residual openings and distribution of proppant along the fracture have a significant effect on well productivity (up to 50 per cent in the case of a relatively low level of confining stresses in the reservoir) and must be incorporated into the evaluation of the efficiency of hydraulic stimulation techniques and assessment of well productivity.Thesis (Ph.D.) -- University of Adelaide, School of Mechanical Engineering, 2013
Conference papers on the topic "Residual fracture opening"
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O’Dowd, Noel P., and Yuebao Lei. "The Effect of Residual Stresses on the Fracture Resistance of Ductile Steels." In ASME 2002 Pressure Vessels and Piping Conference. ASMEDC, 2002. http://dx.doi.org/10.1115/pvp2002-1121.
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Tensile residual stresses, such as those generated by welding, act as crack opening stresses and can have a negative effect on the fatigue and fracture performance of a component. In this work the effect of representative residual stress distributions on the fracture behaviour of a ferritic steel has been examined using finite element analysis. A Gurson-type void growth model is used to model the effect of ductile tearing ahead of a crack. For the cases examined it is seen that a tensile residual stress field may lead to a reduction in the toughness of the material (as represented by the J-resistance curve). The observed difference in toughness can be linked to the different constraint levels in the specimens due to the introduction of the residual stress field and can be rationalised through the use of a two parameter, J–Q approach.
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Smith, Michael C., Peter J. Bouchard, Martin R. Goldthorpe, and Didier Lawrjaniec. "Fracture Margins for Growing Cracks in Weld Repairs." In ASME 2005 Pressure Vessels and Piping Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/pvp2005-71776.
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The residual stress field around a single-pass weld filling a slit in a thin rectangular plate has been simulated using both 2D ABAQUS and 3D SYSWELD finite element models, with good agreement between the two codes. Through-wall cracks of varying lengths have been inserted into the plate along the weld centre-line, and the non-linear crack driving force due to residual stress evaluated using three formulations of the J-integral: the standard ABAQUS J, the G-theta approach coded into SYSWELD, and a modified J-integral, Jmod, that retains its path independence under non-proportional loading. Cracks were introduced into the FE meshes either simultaneously (all crack flank nodes released in the same step) or progressively (crack opened in small increments from mid-length to tip). The results were compared with crack driving force estimates made using linear elastic fracture mechanics (LEFM) and the R6 procedure. The crack driving forces predicted by all three J–formulations agree well for simultaneous opening, showing that the crack driving force rises to a peak for a crack length equal to the weld length, and falls for longer cracks. Linear elastic fracture mechanics gives a good estimate of the crack driving force for very short defects (confirming the absence of elastic follow up), but is conservative for longer defects, overestimating the peak driving force by 20%. The R6 estimates, which incorporate plasticity corrections, are more conservative than LEFM, overestimating the peak crack driving force by up to 60%. The crack driving force for a progressively opened crack is much lower than for simultaneous opening, indicating that there may be considerable excess pessimism in conventional assessments of defects of this type.
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Lewis, Simon J., Christopher E. Truman, and David J. Smith. "A Comparison of 2D and 3D Fracture Assessments in the Presence of Residual Stresses." In ASME 2007 Pressure Vessels and Piping Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/pvp2007-26264.
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This paper presents an investigation into the effects of an initial residual stress field on fracture parameters, calculated via an energy-type integral method, in two and three-dimensional simulations. A residual stress field was introduced into a modified single edge notched bend, SEN(B), specimen using an in-plane compression procedure, such that a crack introduced into the specimen experienced opening displacement, even in the absence of external loading. J integral calculation was undertaken using standard two-dimensional area formulations and pointwise three-dimensional formulations, as well as using modified two- and three-dimensional routines developed to provide path independence in the presence of initial strain fields and non-monotonic plastic loading. The paper will describe the application of these modified J-integral techniques and use the results to re-interpret experimental fracture test data obtained from a set of A533B ferritic steel SEN(B) specimens. The implications for structural integrity assessments in the presence of residual stress fields, as well as the calculation route chosen for determination of fracture parameters, were explored in the context of the R6 assessment procedure. In particular, the different levels of conservatism in the assessments resulting from two- and three-dimensional simulations will be highlighted.
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Haeri, Navid, and Brian A. Cornah. "Repercussion of Autofrettage on the Fatigue Crack Growth in the Vicinity of Catalyst Entry Opening for Polyethylene Autoclave Reactor." In ASME 2015 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/pvp2015-45402.
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Background. The authors conducted a study to analyse the impact of autofrettage practice on the fatigue crack growth in the vicinity of the catalyst entry nozzle in a MK.15 ICI LDPE autoclave reactor. Methods. The authors created 3-D finite element models of the quadrant of the opening. Elastic-plastic analysis was carried out to evaluate the residual stresses from the autofrettage which were then used as an input to the fracture mechanics analysis. Linear Elastic Fracture Mechanics (LEFM) methodology was then deployed associating a Radial Direction, Quarter-Circular Corner Crack pattern as per API 579/ASME VIII Div.3 for the purpose of calculating the crack tip stress intensity. A number of hypothetical pressure cycles were considered in order to calculate the crack growth rate as per ASME Div.3 (Paris’ Law) both with and without residual stresses from autofrettage analysis. Results. The study results showed the change in the crack behaviour as a result of adding the autofrettage residual stresses onto the model and discussed the implications of such a practice on the design life for autoclave reactors.
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Dewees, David J., and Robert H. Dodds. "Comparison of Flaw Driving Force Estimates in Simulated Weld Residual Stress Fields." In ASME 2013 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/pvp2013-97410.
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Previous work has focused on the methods and results for calculating flaw driving force in simulated three-dimensional (3D) weld residual stress (WRS) fields using contour (J) integral techniques. This paper extends that work to look at explicit modeling of the crack tip opening displacement (CTOD) in these same WRS fields, and for the same range of semi-elliptical flaws. Comparison is made between the predicted trends of driving force with crack size for the calculated driving force (J-integral) versus the “measured” value (CTOD). Implications for fracture assessments are given, and recommendations for future work are made.
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Seko, Yusuke, Yasuhito Imai, Masaki Mitsuya, Noritake Oguchi, and Fumiyoshi Minami. "Application of Weibull Stress Criterion to Brittle Fracture Assessment of HAZ-Notched Welds With Residual Stress." In 2014 10th International Pipeline Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/ipc2014-33731.
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This paper presents a method for estimating the brittle fracture limit of a weld with a notch in the heat-affected zone (HAZ) and residual stress based on the Weibull stress criterion. A constraint loss correction procedure using the Weibull stress criterion is specified in ISO 27306. However, this standard is applicable only to structural steel components with defects, not to welded joints. Therefore, we conducted fracture tests and finite element analyses to propose a new evaluation method for welded structural components. In this study, three-point bending (3PB) tests and wide-plate (WP) tension tests of HAZ-notched welds made of 780-MPa-class high-strength steel were conducted at −40°C. Brittle fractures occurred in the HAZ regions of all the specimens, and the critical crack tip opening displacement (CTOD) values obtained in the 3PB and WP tests were approximately 0.02–0.07 mm and 0.08–0.11 mm, respectively. The minimum critical CTOD of the WP specimen fracturing at the coarse-grained region of the HAZ (CGHAZ) was approximately four times that of the 3PB specimen. These results confirmed that the difference of specimen geometry affects the brittle fracture resistance of a HAZ-notched weld with residual stress. Hence, the assessment of the brittle fracture limit of a welded structural component with a defect obtained by the fracture toughness of a 3PB specimen would be excessively conservative. The effects of specimen geometry, residual stress, crack-front shape and HAZ microstructure classification on the Weibull stress were investigated to clarify the difference of experimental critical CTOD for 3PB and WP by using a finite element analysis. The results of this analysis showed that the Weibull stress of WP specimen was larger than one of 3PB specimen in all CTOD region due to difference of geometry. The welding residual stress increased the Weibull stress only for WP. Compressive residual stress and crack front shape for 3PB specimen did not affect the Weibull stress. The difference of HAZ microstructure distribution for same welded joint affects the Weibull stress for 3PB and WP specimens. Finally, it was confirmed that the brittle fracture limit of a HAZ-notched weld with residual stress could be predicted from the Weibull stress criterion because critical CTOD of WP specimens predicted by critical CTOD of 3PB specimens fracturing at the CGHAZ included critical CTOD of WP specimens obtained by experiments.
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Kamel, Simon, Noel P. O’Dowd, and Kamran M. Nikbin. "Numerical Investigation to Examine the Effect of Introducing a Crack in a Residual Stress Field." In ASME 2008 Pressure Vessels and Piping Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/pvp2008-61513.
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This paper presents a detailed two dimensional finite-element study to examine the effect of introducing a crack either progressively or instantaneously into a residual stress field. A progressive crack is defined as a crack which is introduced in fixed increments of crack extension until the desired crack length is achieved. An instantaneous crack is one in which a crack of the required length is introduced instantaneously into the finite-element mesh. Inspection is made of the crack tip fields and the crack opening displacements. A modified definition of the J-integral, which accounts for the initial plastic strain due to residual stress, is assessed, in order to examine its ability to characterise the intensity of the near crack tip fields. The implications of the results on fracture assessment of structural components are discussed.
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Tokiyoshi, Takumi, Toshihide Igari, Nobuyuki Takao, and Akihiro Kanaya. "Estimation of Fracture Mechanics Parameters Under Displacement-Controlled Elastic Plastic Fatigue Conditions." In ASME/JSME 2004 Pressure Vessels and Piping Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/pvp2004-2254.
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Accurate prediction of the residual life of components under long-term service is urgently needed due to requirements for the reduction of the maintenance costs of thermal power plants. Quantitative prediction of crack growth under displacement-controlled conditions such as thermal fatigue is a key to the fulfillment of this need. In a previous paper, the present authors proposed a simplified prediction method of fracture mechanics parameters such as J and C* of a perforated plate under thermal fatigue, on the basis of the reference stress approach under displacement-controlled conditions. In this paper, the fracture mechanics parameters of a CCT specimen and structural models of CrMoV cast steel under displacement-controlled conditions were numerically and experimenttally examined on the basis of the proposed method. The ratio of the elastic and the inelastic crack opening displacement, as well as the ratio of the elastic and the inelastic load point displacement, was used to correlate the fracture mechanics parameters in the elastic and inelastic region. As a result of the study, the proposed method based on displacement was found to be insensitive to small variation in the predicted results of macroscopic load in comparison with the original reference stress method, and is considered to be applicable to displacement-controlled conditions such as thermal fatigue.
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Clark, Robert, Ali Husain, and Stephen Rainey. "Successful Post-Fracture Stimulation Well Cleanup and Testing of Tight Gas Reservoirs in the Sultanate of Oman." In SPE Middle East Unconventional Resources Conference and Exhibition. SPE, 2015. http://dx.doi.org/10.2118/spe-172957-ms.
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Abstract Tight gas/tight oil reservoirs require fracture stimulation to achieve commercial rates of hydrocarbons. Fracturing operations involve pumping considerable volumes of proppant and water/gel into the reservoir. Rapid cleanup of fracturing fluids and residual proppant ensures the desired goals of the stimulation operations are achieved: enhancing the flow capacity of the well while minimizing the risk of proppant damage to surface equipment. It is normal for significant quantities of proppant and frac fluid to flow back after opening the well for cleanup. Frac fluid often contains broken cross-linked gel, which must be flowed back to ensure cleanup of the fracture and minimize plugging of the fracture face and the proppant pack. In North America, it is not unusual for frac fluid recovery to be only a small fraction of the amount of injected fluid. Frac fluid recovery of 5 to 30 percent is not unusual and 50 percent is often considered excellent. In the Sultanate of Oman, BP is currently achieving 50 to 90 percent frac fluid recovery, while pressure transient analysis indicates post-frac skin damage figures of -6 or better, indicating excellent stimulation effectiveness. Critically, no proppant has flowed through to the surface facility. These cleanup procedures have been conducted in wells with a variety of frac types including 450,000 to 1,000,000 lb cross-linked gel fracs and multiple 17,000 bbl slick water fracs. An analysis of the procedures used to achieve these results will be presented in this paper. It indicates that allowing the frac to close and opening the well on a moderate choke, with re-direction of the post-frac fluid through effective sand management systems, followed by flowing the well at a managed drawdown against the reservoir has achieved excellent results. These results underpinned the decision to move forward in this multi-billion dollar development project.
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Toft, Adam, David Beardsmore, Colin Madew, Huego Teng, and Mark Jackson. "Displacement Controlled Stress Intensity Factor Solutions for Structural Integrity Assessments of Welding Residual Stress Distributions." In ASME 2008 Pressure Vessels and Piping Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/pvp2008-61211.
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Within the UK nuclear industry the assessment of fracture in pressurised components is often carried out using procedures to calculate the margin of safety between a lower-bound fracture toughness and the crack driving force. Determination of the crack driving force usually requires the calculation of elastic stress intensity factor solutions for primary loads and secondary loads arising from weld residual stresses and/or thermal stresses. Within established UK assessment procedures weight function solutions are available which allow the stress intensity factors to be calculated from the through-wall opening-mode stress distribution in an uncracked component. These weight-function solutions are generally based on models where either no boundary condition is applied, or where one is applied at a distance either side of the crack plane that is very long compared with the crack size and wall thickness. Such solutions do not take into account any reduction in the stress field that might occur as the distance from the crack faces increases. Weld residual stress fields may often be expected to reduce in this manner. A separate, earlier study has shown that the stress intensity factor for a cracked plate loaded in displacement control decreases substantially as the loading plane is moved closer to the crack plane. It would therefore be expected that a similar reduction in stress intensity factor would be obtained for a residual stress analysis when displacement boundary conditions are imposed at a distance relatively close to the crack plane. This paper describes an investigation of the differences, particularly in terms of a reduction in calculated stress intensity factor, which may arise from application of displacement controlled stress intensity factor solutions, as compared with load controlled solutions, when considering weld residual stresses. Consideration is also given as to how new displacement controlled stress intensity factor solutions could be developed by modification of existing load controlled solutions.