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Francis Claret - One of the best experts on this subject based on the ideXlab platform.
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Well integrity assessment under temperature and pressure stresses by a 1:1 scale wellbore experiment
2019Co-Authors: Jean-charles Manceau, Catherine Lerouge, Joachim Tremosa, C. Nussbaum, L. Wasch, Pascal Audigane, Francis Claret, Y. Lettry, T. Fierz, Fabrizio GherardiAbstract:An innovative in situ experiment has been proposed for observing and understanding well integrity evolution, in the context of CO 2 storage operations. This experiment took place between 2012 and 2015 and is documented in Manceau et al. (2015) and in Manceau et al. (2016). A small section of a well is reproduced at scale 1:1 in the Opalinus Clay formation, representative of a low permeable caprock formation (in Mont Terri Underground Rock Laboratory, Switzerland). The well-system behavior is characterized over time both by performing hydro-tests to quantify the hydraulic properties of the well and their evolution, and sampling the fluids to monitor the chemical composition and its changes. A first stage (stage A) has been focused on the well integrity assessment under different imposed temperature (17-52°C) and pressure (10-28 bar) conditions. A second stage (stage B) has been dedicated to the exposure of the system to CO 2-rich pore water. A final overcoring stage has allowed retrieving the well system and the Surrounding Clay. Multidisciplinary methods (hydraulic tests and modelling, fluid sampling and modelling, analysis of cement and Clay samples on the overcore) are used together to get better insight, in a realistic wellbore context, on the interplay between the geochemical questions, and the operational and construction issues. The following key messages have been identified regarding the understanding of processes affecting the integrity of a well-The relatively high initial effective well permeability (observed at the beginning of stage A) has been explained by a migration along the cement/Clayinterface, possibly due to cement shrinkage, while the cement matrix and the Clay-rich caprock close to the well appeared to be a very good barrier to unwanted fluid migration : this showed that the potential weakest points are interfaces between well elements rather than the well elements themselves, if appropriate materials are used.-The significant variations of the effective well permeability observed after setting pressure and temperature stresses indicate that operations could influence well integrity in similar proportions than the cementing process.-The cement has correctly protected the steel casing from corrosion, except in one small area, where the cement sheath was absent and where the corrosion was important. This showed that an appropriate cementing is compulsory to avoid issues regarding well integrity but also the importance of corrosion prevention measures implementation.-The hydraulic conductivity of the well-system was significantly lowered during exposure to CO 2-rich pore water. In that context, the well integrity did not appear to have been compromised, but rather improved by the geochemical reactions. This showed that,when good integrity pre-exists before a well is in contact with car-bonated water, the exposure to dissolved CO 2 does not seem to lead to a degradation of the well hydraulic properties but rather to their improvement. Finally, this study confirms the ability of this type of experiment (1:1 scale in a controlled environment) to improve our knowledge on complex phenomena (thermal, mechanical, hydraulic and geochemical) occurring at a realistic scale, which is especially important for well integrity. Such experimental works may indeed allow an integration of a maximum of realistic processes, the monitoring of parameters usually only measurable in the field (e.g. effective well permeability) and the validation of the upscaling of laboratory results.
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Well integrity assessment by a 1:1 scale wellbore experiment: Exposition to dissolved CO2 and overcoring
International Journal of Greenhouse Gas Control, 2016Co-Authors: Jean-charles Manceau, Catherine Lerouge, Joachim Tremosa, Fabrizio Gherardi, C. Nussbaum, L. Wasch, Patrick Albéric, Pascal Audigane, Francis ClaretAbstract:In this work, we present the results of a new in situ experiment to complete the existing scientific dataset on well integrity in the context of CO2 storage. This experimentation has been designed to evaluate the sealing behaviour of a monitored well after mechanical and chemical stresses due to pressure and temperature changes (stage A) and due to the exposure to carbonated brine (stage B), before a final overcoring stage for retrieving the well system and the Surrounding Clay. The stage A has been the subject of a first publication (Manceau et al., 2015; Water Resour. Res., 51, 6093–6109) and the two latter stages are described in this paper. Multidisciplinary methods (hydraulic tests and modelling, fluid sampling and modelling, analysis of cement and Clay samples on the overcore) are used to get better insight, in a realistic wellbore context, on the interplay between the geochemical questions, and the operational and construction issues. In particular, this study shows that when good integrity pre-exists before a well is in contact with carbonated water, the exposure to dissolved CO2 does not seem to lead to a degradation of the well hydraulic properties but rather to their improvement.
Mitsuo Nozu - One of the best experts on this subject based on the ideXlab platform.
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Undrained Shear Strength of Clay Improved with Sand Compaction Piles
Soils and Foundations, 1994Co-Authors: Akira Asaoka, Takeshi Kodaka, Mitsuo NozuAbstract:The Sand Compaction Pile (SCP) method is considered to be a displacement type pile method, in which a considerable amount of "set-up" of the undrained shear strength of the Surrounding Clay is anticipated. A simplified procedure for analyzing the set-up problem is presented in two stages. The first stage is the soil-water coupled rigid plastic finite element method which is employed for solving undrained failure of Clay due to pile driving, and the other, a linear elastic consolidation computation which accounts for the decrease of void ratio of the Clay after pile driving. The value of this simplified method is examined through (1) laboratory set-up experiment on a remoulded Kawasaki Clay using a triaxial apparatus aud (2) the case record of in-situ loading test on soft Clay improved with the SCP method. In the latter case, extensive improvement in the soft Clay was found particularly at a large depth of the soft Clay layer, where the set-up ratio was more than two.
Jean-charles Manceau - One of the best experts on this subject based on the ideXlab platform.
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Well integrity assessment under temperature and pressure stresses by a 1:1 scale wellbore experiment
2019Co-Authors: Jean-charles Manceau, Catherine Lerouge, Joachim Tremosa, C. Nussbaum, L. Wasch, Pascal Audigane, Francis Claret, Y. Lettry, T. Fierz, Fabrizio GherardiAbstract:An innovative in situ experiment has been proposed for observing and understanding well integrity evolution, in the context of CO 2 storage operations. This experiment took place between 2012 and 2015 and is documented in Manceau et al. (2015) and in Manceau et al. (2016). A small section of a well is reproduced at scale 1:1 in the Opalinus Clay formation, representative of a low permeable caprock formation (in Mont Terri Underground Rock Laboratory, Switzerland). The well-system behavior is characterized over time both by performing hydro-tests to quantify the hydraulic properties of the well and their evolution, and sampling the fluids to monitor the chemical composition and its changes. A first stage (stage A) has been focused on the well integrity assessment under different imposed temperature (17-52°C) and pressure (10-28 bar) conditions. A second stage (stage B) has been dedicated to the exposure of the system to CO 2-rich pore water. A final overcoring stage has allowed retrieving the well system and the Surrounding Clay. Multidisciplinary methods (hydraulic tests and modelling, fluid sampling and modelling, analysis of cement and Clay samples on the overcore) are used together to get better insight, in a realistic wellbore context, on the interplay between the geochemical questions, and the operational and construction issues. The following key messages have been identified regarding the understanding of processes affecting the integrity of a well-The relatively high initial effective well permeability (observed at the beginning of stage A) has been explained by a migration along the cement/Clayinterface, possibly due to cement shrinkage, while the cement matrix and the Clay-rich caprock close to the well appeared to be a very good barrier to unwanted fluid migration : this showed that the potential weakest points are interfaces between well elements rather than the well elements themselves, if appropriate materials are used.-The significant variations of the effective well permeability observed after setting pressure and temperature stresses indicate that operations could influence well integrity in similar proportions than the cementing process.-The cement has correctly protected the steel casing from corrosion, except in one small area, where the cement sheath was absent and where the corrosion was important. This showed that an appropriate cementing is compulsory to avoid issues regarding well integrity but also the importance of corrosion prevention measures implementation.-The hydraulic conductivity of the well-system was significantly lowered during exposure to CO 2-rich pore water. In that context, the well integrity did not appear to have been compromised, but rather improved by the geochemical reactions. This showed that,when good integrity pre-exists before a well is in contact with car-bonated water, the exposure to dissolved CO 2 does not seem to lead to a degradation of the well hydraulic properties but rather to their improvement. Finally, this study confirms the ability of this type of experiment (1:1 scale in a controlled environment) to improve our knowledge on complex phenomena (thermal, mechanical, hydraulic and geochemical) occurring at a realistic scale, which is especially important for well integrity. Such experimental works may indeed allow an integration of a maximum of realistic processes, the monitoring of parameters usually only measurable in the field (e.g. effective well permeability) and the validation of the upscaling of laboratory results.
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Well integrity assessment by a 1:1 scale wellbore experiment: Exposition to dissolved CO2 and overcoring
International Journal of Greenhouse Gas Control, 2016Co-Authors: Jean-charles Manceau, Catherine Lerouge, Joachim Tremosa, Fabrizio Gherardi, C. Nussbaum, L. Wasch, Patrick Albéric, Pascal Audigane, Francis ClaretAbstract:In this work, we present the results of a new in situ experiment to complete the existing scientific dataset on well integrity in the context of CO2 storage. This experimentation has been designed to evaluate the sealing behaviour of a monitored well after mechanical and chemical stresses due to pressure and temperature changes (stage A) and due to the exposure to carbonated brine (stage B), before a final overcoring stage for retrieving the well system and the Surrounding Clay. The stage A has been the subject of a first publication (Manceau et al., 2015; Water Resour. Res., 51, 6093–6109) and the two latter stages are described in this paper. Multidisciplinary methods (hydraulic tests and modelling, fluid sampling and modelling, analysis of cement and Clay samples on the overcore) are used to get better insight, in a realistic wellbore context, on the interplay between the geochemical questions, and the operational and construction issues. In particular, this study shows that when good integrity pre-exists before a well is in contact with carbonated water, the exposure to dissolved CO2 does not seem to lead to a degradation of the well hydraulic properties but rather to their improvement.
Shuilong Shen - One of the best experts on this subject based on the ideXlab platform.
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Deep Mixing Induced Property Changes in Surrounding Sensitive Marine Clays
Journal of Geotechnical and Geoenvironmental Engineering, 2008Co-Authors: Shuilong Shen, Jie HanAbstract:This paper presents a field study of installation effects of deep mixed columns on properties of the sensitive Ariake marine Clay. Cone penetration tests were performed in the field to evaluate the change in the strength of the Surrounding Clay with time. Soil samples were taken before and after column installation to evaluate variations of physical, mechanical, and chemical properties of the Surrounding Clay. Test results indicated that the water content of the Surrounding Clay decreased while the concentration of cations increased as sampling locations approached the columns. Shear strength of the Surrounding Clay decreased during the installation but recovered after a short period of curing. Shear strength continued to increase with time over a period of 70 days. Based on the regression results, the Surrounding soil after the installation of the columns took approximately 10 days to recover to the strength value before installation. On average, the shear strength of the Surrounding Clay increased over the original strength by approximately 23% after 40 days and 50% after 70 days, respectively. Discussion is presented on strength changes and key influence factors including soil disturbance and fracturing, thixotropy, consolidation, and diffusion of cations from deep mixed columns to the Surrounding Clay.
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Interaction mechanism between deep mixing column and Surrounding Clay during installation
Canadian Geotechnical Journal, 2003Co-Authors: Shuilong Shen, Norihiko Miura, Hirofumi KogaAbstract:Laboratory and field investigation has shown that the shear strength of the Surrounding Clay increased in the vicinity of a deep mixed (DM) column in the short period following installation. Field observations indicated that significant excess pore pressure, which may be higher than the hydraulic fracture pressure, was generated during installation.The behaviour between a DM column interacting with the Surrounding Clay during installation can be simulated as the shearing-expanding process of a cylindrical cavity. A simple approach is proposed to calculate the excess pore pressure around a DM column during installation. The proposed method of calculation considers the effect of a shearing force caused by rotating blades during mixing. In the proposed approach, the excess pore pressure is expressed in terms of undrained strength of Clay, shearing force, injection pressure, and a pore pressure parameter. An approach is developed to analyze Clay fracturing using a tensile failure mechanism. Analytical results...
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Laboratory Studies on Property Changes in Surrounding Clays Due to Installation of Deep Mixing Columns
Marine Georesources & Geotechnology, 2003Co-Authors: Shuilong Shen, Xing-chun Huang, Jie HanAbstract:This paper has identified six major factors causing property changes in Surrounding soils during and after installation of deep mixing columns: soil thixotropy, soil fracturing, cement penetration and diffusion, cementation, consolidation, and heating. Laboratory tests were performed to investigate the effects of soil thixotropy, soil fracturing, and cementation in a soft marine Clay, Ariake Clay. Laboratory tests were conducted to evaluate property changes in Surrounding Clays due to installation of deep mixing columns. Test results showed that an influential zone of property changes existed in Surrounding Clay ranging from the edge of the columns to the distance of about twice the radius of the columns. Within this influential zone, water content decreased as samples neared the columns, while pH values and electric conductivity increased. Test results also showed that undrained shear strengths of the Surrounding Clays decreased during mixing but regained after a 7-day curing period and continued increas...
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soil fracturing of the Surrounding Clay during deep mixing column installation
Soils and Foundations, 1999Co-Authors: Shuilong Shen, Norihiko MiuraAbstract:During deep mixing (DM) column installation, excess pore pressure arises in the Surrounding Clay due to the injection of chemical admixtures and the shearing action caused by blade rotation. The excess pore pressure is greater than the in-situ effective stress, resulting in fractures in the Surrounding Clay. Pore water infiltrates into fractures, and the consolidation of Clay is accelerated. The chemical admixture penetrates into the fractures and thereby exchangeable cations diffuse into the Surrounding Clay effectively. All of these effects accelerate the strength increase of the Surrounding Clay after the installation of DM columns. The main objective of this study is to confirm the aforementioned phenomena. These phenomena are verified through (1) a laboratory vane shear test, (2) a laboratory test on a model column made in a model Clay ground, and (3) full-scale field tests on DM column installation.
Fabrizio Gherardi - One of the best experts on this subject based on the ideXlab platform.
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Well integrity assessment under temperature and pressure stresses by a 1:1 scale wellbore experiment
2019Co-Authors: Jean-charles Manceau, Catherine Lerouge, Joachim Tremosa, C. Nussbaum, L. Wasch, Pascal Audigane, Francis Claret, Y. Lettry, T. Fierz, Fabrizio GherardiAbstract:An innovative in situ experiment has been proposed for observing and understanding well integrity evolution, in the context of CO 2 storage operations. This experiment took place between 2012 and 2015 and is documented in Manceau et al. (2015) and in Manceau et al. (2016). A small section of a well is reproduced at scale 1:1 in the Opalinus Clay formation, representative of a low permeable caprock formation (in Mont Terri Underground Rock Laboratory, Switzerland). The well-system behavior is characterized over time both by performing hydro-tests to quantify the hydraulic properties of the well and their evolution, and sampling the fluids to monitor the chemical composition and its changes. A first stage (stage A) has been focused on the well integrity assessment under different imposed temperature (17-52°C) and pressure (10-28 bar) conditions. A second stage (stage B) has been dedicated to the exposure of the system to CO 2-rich pore water. A final overcoring stage has allowed retrieving the well system and the Surrounding Clay. Multidisciplinary methods (hydraulic tests and modelling, fluid sampling and modelling, analysis of cement and Clay samples on the overcore) are used together to get better insight, in a realistic wellbore context, on the interplay between the geochemical questions, and the operational and construction issues. The following key messages have been identified regarding the understanding of processes affecting the integrity of a well-The relatively high initial effective well permeability (observed at the beginning of stage A) has been explained by a migration along the cement/Clayinterface, possibly due to cement shrinkage, while the cement matrix and the Clay-rich caprock close to the well appeared to be a very good barrier to unwanted fluid migration : this showed that the potential weakest points are interfaces between well elements rather than the well elements themselves, if appropriate materials are used.-The significant variations of the effective well permeability observed after setting pressure and temperature stresses indicate that operations could influence well integrity in similar proportions than the cementing process.-The cement has correctly protected the steel casing from corrosion, except in one small area, where the cement sheath was absent and where the corrosion was important. This showed that an appropriate cementing is compulsory to avoid issues regarding well integrity but also the importance of corrosion prevention measures implementation.-The hydraulic conductivity of the well-system was significantly lowered during exposure to CO 2-rich pore water. In that context, the well integrity did not appear to have been compromised, but rather improved by the geochemical reactions. This showed that,when good integrity pre-exists before a well is in contact with car-bonated water, the exposure to dissolved CO 2 does not seem to lead to a degradation of the well hydraulic properties but rather to their improvement. Finally, this study confirms the ability of this type of experiment (1:1 scale in a controlled environment) to improve our knowledge on complex phenomena (thermal, mechanical, hydraulic and geochemical) occurring at a realistic scale, which is especially important for well integrity. Such experimental works may indeed allow an integration of a maximum of realistic processes, the monitoring of parameters usually only measurable in the field (e.g. effective well permeability) and the validation of the upscaling of laboratory results.
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Well integrity assessment by a 1:1 scale wellbore experiment: Exposition to dissolved CO2 and overcoring
International Journal of Greenhouse Gas Control, 2016Co-Authors: Jean-charles Manceau, Catherine Lerouge, Joachim Tremosa, Fabrizio Gherardi, C. Nussbaum, L. Wasch, Patrick Albéric, Pascal Audigane, Francis ClaretAbstract:In this work, we present the results of a new in situ experiment to complete the existing scientific dataset on well integrity in the context of CO2 storage. This experimentation has been designed to evaluate the sealing behaviour of a monitored well after mechanical and chemical stresses due to pressure and temperature changes (stage A) and due to the exposure to carbonated brine (stage B), before a final overcoring stage for retrieving the well system and the Surrounding Clay. The stage A has been the subject of a first publication (Manceau et al., 2015; Water Resour. Res., 51, 6093–6109) and the two latter stages are described in this paper. Multidisciplinary methods (hydraulic tests and modelling, fluid sampling and modelling, analysis of cement and Clay samples on the overcore) are used to get better insight, in a realistic wellbore context, on the interplay between the geochemical questions, and the operational and construction issues. In particular, this study shows that when good integrity pre-exists before a well is in contact with carbonated water, the exposure to dissolved CO2 does not seem to lead to a degradation of the well hydraulic properties but rather to their improvement.