Carlos Delahaye | Universidad Nacional de San Juan (original) (raw)
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Abstract: The paper presents general conclusions derived from a two dimensional unsaturated flow ... more Abstract: The paper presents general conclusions derived from a two dimensional unsaturated flow analysis coupled with a slope stability evaluation using limit equilibrium analysis. The change in strength is taken into account by means of a linear increment of ...
... 10). Beyond full saturation, the air pressure is essentially controlled by Henry&... more ... 10). Beyond full saturation, the air pressure is essentially controlled by Henry's law and the (slow) air diffusion process. ... The consideration of natural anisotropy and mechanical effects enhances the development of preferential paths for gas migration. ...
2020 IEEE Congreso Bienal de Argentina (ARGENCON)
Uno de los equipamientos más importantes de un laboratorio de alta tensión es el Equipo para Ensa... more Uno de los equipamientos más importantes de un laboratorio de alta tensión es el Equipo para Ensayos en Alta Tensión en Corriente Alterna a Frecuencia Industrial. Siendo su Unidad de Comando el elemento que más sufre el paso del tiempo ya que su tecnología se vuelve obsoleta, su reemplazo se convierte en prioritario. Con el propósito de aportar una solución eficiente y de bajo costo a este problema, evitando reemplazar la unidad de comando con tecnología actualizada, se puede concebir la posibilidad de eliminar físicamente dicho componente y emplear un programa de computadora especializado que realice la misma función. Este trabajo describe un programa como el citado, desarrollado bajo la plataforma LabVIEW, la cual ofrece muchas prestaciones, lo que permite no sólo realizar las funciones inherentes de la unidad de comando sino también introducir mejoras tanto en la seguridad de equipamientos y personas como en las técnicas de medición en alta tensión.
Se han investigado, mediante ensayos de laboratorio, las características de hidratación de mezcla... more Se han investigado, mediante ensayos de laboratorio, las características de hidratación de mezclas expansivas constituidas por una matriz de polvo arcilloso y agregados (pastillas de pequeño tamaño) de arcilla de alta densidad. Estas mezclas se han propuesto como material de relleno para aislar residuos potencialmente contaminantes del medio geológico que los rodea. Se ha simulado el comportamiento de este material de relleno bajo las condiciones existentes "in situ" mediante un análisis hidro-mecánico acoplado. En el análisis, el relleno se caracterizó de acuerdo con los resultados del programa de ensayos de laboratorio.Postprint (published version
Revista de Geología Aplicada a la Ingeniería y al Ambiente, 2015
El artículo analiza el desarrollo de flujo preferencial en pilas de lixiviación debido a la heter... more El artículo analiza el desarrollo de flujo preferencial en pilas de lixiviación debido a la heterogeneidad del mineral apilado. La heterogeneidad del material se describe mediante campos de permeabilidades aleatorios que aumentan la conectividad de los poros, con una media constante y una función de covariancia que depende del vector distancia relativa entre dos puntos arbitrarios. Puesto que los datos relativos a la variabilidad del material a pequeña escala es muy limitada, se mantiene una estrecha relación con los datos macroscópicos promedio medidos (homogéneo). Una vez definido el modelo de suelo heterogéneo, se utiliza un código termo-hidro-mecánico acoplado de propósito general para realizar el análisis. El mineral está inicialmente en estado no saturado y se simula el riego de la pila a una tasa determinada. Las características geotécnicas del material son representativas del mineral
A set of subroutines have been developed, in order to min1mlze the CPO time and storinq requireme... more A set of subroutines have been developed, in order to min1mlze the CPO time and storinq requirements in processinq block matrix products using non zero elements of each block matrix or non zero rows (columns). Comparation is set among product of blocks considered as sparse matrixes (column matrixes) or complete matrixes. Advantajes are ahown by results been obtained, in using developed techniques.
Se han investigado, mediante ensayos de laboratorio, las caracteristicas de hidratacion de mezcla... more Se han investigado, mediante ensayos de laboratorio, las caracteristicas de hidratacion de mezclas expansivas constituidas por una matriz de polvo arcilloso y agregados (pastillas de pequeno tamano) de arcilla de alta densidad. Estas mezclas se han propuesto como material de relleno para aislar residuos potencialmente contaminantes del medio geologico que los rodea. Se ha simulado el comportamiento de este material de relleno bajo las condiciones existentes "in situ" mediante un analisis hidro-mecanico acoplado. En el analisis, el relleno se caracterizo de acuerdo con los resultados del programa de ensayos de laboratorio. Hydration characteristics of an expansive mixture of compacted clay matrix and high density pellets ha ve been investigated by means of laboratory tests. These mixtures are proposed as a suitable barrier material to isolate hazardous wastes from the surrounding geological environment. The behaviour of this material under conditions prevailing "in situ" has been simulated by means of a coupled flow-deformation analysis. The backfill was characterized according to the results of the laboratory tests program.
Engineering Geology, 2002
Preferential paths are often reported in connection with gas breakthrough experiments. These pref... more Preferential paths are often reported in connection with gas breakthrough experiments. These preferential paths may be explained, in a deformable soil skeleton, by the action of pressurised gas along a natural path. A natural path is defined in a spatially heterogeneous material by a set of connected spots of higher gas permeability. Along this path the soil will experience a marked desaturation and gas permeability will increase fast. The paper describes a procedure to simulate these effects. Soil heterogeneity is described by means of random fields, which describe the key soil properties for gas migration. Since actual data concerning soil variability at a small (sample) scale is very limited, a number of computer models of increased complexity have been developed. They maintain, however, a close relationship with the known macroscopic data of the average (homogeneous) sample. The effect of some hypothesis concerning the stochastic structure of soil variability and the role of the hydromechanical coupling has also been explored. Once the heterogeneous soil model is defined, a general purpose code for Thermo-Hydro-Mechanical analysis is subsequently used to perform the analysis. The soil is initially saturated and a non-wetting phase (gas) is forced through the saturated mass either at constant pressure or at a constant flow rate. The results of the different analyses are compared in order to advance in the basic understanding of gas migration through clay barriers. Finally, a discussion of the relevance of soil heterogeneity, on the basis of the analysis performed, is presented.
La distribucion espacial de la conductividad hidraulica es una de las propiedades que mas influye... more La distribucion espacial de la conductividad hidraulica es una de las propiedades que mas influye sobre el flujo de liquido de solucion extractiva, a traves de una pila de lixiviacion de minerales. En este trabajo se presenta una metodologia basada en tecnicas geoestadisticas y geofisicas para determinar la distribucion espacial de la conductividad hidraulica en una pila de lixiviacion de minerales. El estudio se realiza con la informacion proporcionada por perfiles geofisicos realizados en la pila de lixiviacion de minerales del Proyecto Minero Gualcamayo, ubicado en el departamento Jachal de la provincia de San Juan. La variable proporcionada por la geofisica es la resistividad electrica. El analisis estadistico y geoestadistico de esta propiedad permite tanto estimar valores de resistividad electrica en unidades volumetricas, como la varianza del error, que da una idea de la precision y el grado de incertidumbre en la estimacion. De esta forma, se obtiene un modelo matematico de ...
En este trabajo se analiza el comportamiento de aberturas subterraneas mediante el empleo de un m... more En este trabajo se analiza el comportamiento de aberturas subterraneas mediante el empleo de un modelo en elementos finitos bidimensionales (2D) no lineal (elasto-plastico), con ley de fluencia de Mohr-Coulomg. En primer lugar se estudia una galeria aislada de acceso a una mina con seccion transversal circular o abovedada. A continuacion se comprueba el diseno del pilar entre dos galerias adyacentes y paralelas. El grado de seguridad del diseno se determina en funcion de un coeficiente de seguridad frente a la plastificacion.
The option of the disposal of radioactive waste in a deep clay layer is actually studied in Belgi... more The option of the disposal of radioactive waste in a deep clay layer is actually studied in Belgium, France, Spain and Netherlands. Immediately after closure and sealing of a geological radioactive waste repository a range of gases will be generated. Due to the low permeability of the clay materials these gases cannot easily escape. This can lead to an increase in pressure in the repository and to the creation of preferential gas pathways. In this paper, as a first step towards the development of computational techniques to handle flow of gas through compacted and natural clays, and to advance in the basic understanding of the gas migration issues associated with repository safety, the capabilities of a general code for coupled thermo-hydro-mechanical analysis have been explored. Some laboratory gas injection experiments carried out on natural clay samples have been selected in order to compare model computations with measured specimen of natural clay performance. The results show t...
Engineering Geology, 2002
Preferential paths are often reported in connection with gas breakthrough experiments. These pref... more Preferential paths are often reported in connection with gas breakthrough experiments. These preferential paths may be explained, in a deformable soil skeleton, by the action of pressurised gas along a natural path. A natural path is defined in a spatially heterogeneous material by a set of connected spots of higher gas permeability. Along this path the soil will experience a marked desaturation and gas permeability will increase fast. The paper describes a procedure to simulate these effects. Soil heterogeneity is described by means of random fields, which describe the key soil properties for gas migration. Since actual data concerning soil variability at a small (sample) scale is very limited, a number of computer models of increased complexity have been developed. They maintain, however, a close relationship with the known macroscopic data of the average (homogeneous) sample. The effect of some hypothesis concerning the stochastic structure of soil variability and the role of the...
BACCHUS2 in situ isothermal wetting experiment has been analysed by means of a coupled flowdeform... more BACCHUS2 in situ isothermal wetting experiment has been analysed by means of a coupled flowdeformation approach. Backfill material, a mixture of Boom clay powder and high density pellets, has been extensively tested in the laboratory in order to determine its hydraulic and mechanical properties. Parameters of constitutive equations were derived from this experimental data base. Two mechanical constitutive models have been used in the simulation of the 'in situ' experiment: a state surface approach and an elastoplastic model. Calculations have shown several features of the hydration process which help to understand the behaviour of expansive clay barriers. Predictions using both models have been compared with each other and with actual measurement records. This has allowed a discussion of the comparative mertis of both approaches and the identification of some critical parameters of backfill behaviour. Overall agreement between calculations and field measurements is encouraging and shows the potential of the methods developed to model the behaviour of engineered clay barriers in the context of nuclear waste disposal.
The behaviour of an instrumented unstable slope in a profile of weathered overconsolidated clay h... more The behaviour of an instrumented unstable slope in a profile of weathered overconsolidated clay has been analysed. Available field investigation data and laboratory tests were integrated in a coupled hydromechanical model of the slope. Particular attention was given to the unsaturated soil conditions above the water table and to the influence of the rainfall record. Recorded pore-water pressures helped to identify the hydrogeological conditions of the slope. The coupled model was used to compute slope deformations and the variation of safety with time. Actual rainfall records were also integrated into the analysis. Comparison of measurements and calculations illustrate the nature of the slope instability and the complex relationships between mechanical and hydraulic factors. Résumé Une pente instable dans un profil d'argile altérée sur-consolidée a été instrumentée et son comportement a été analysé. Des données disponibles obtenues lors d'étude sur le terrain et des essais en laboratoire ont été intégrés dans un modèle couplé hydromécanique de la pente. Une attention particulière a été portée aux conditions du sol non saturé au-dessus de la nappe et à l'influence de la succession de pluies. Les pressions enregistrées de l'eau dans les pores ont permis d'identifier les conditions hydrogéologiques de la pente. Le modèle couplé a été utilisé pour calculer les déformations de la pente et la variation de sécurité au cours du temps. Les enregistrement de pluies réelles ont été également intégrés à l'analyse. La comparaison des mesures aux calculs illustre la nature de l'instabilité de la pente et les relations complexes entre les facteurs mécaniques et hydrauliques. Resumen Se ha analizado el comportamiento de una ladera instable que fue instrumentada en un perfil de arcillas meteorizadas sobreconsolidadas. Se ha integrado los datos disponibles de investigaciones de campo y ensayos de laboratorio en un modelo hidromecánico acoplado de la ladera, prestando una atención especial a las condiciones del suelo no saturado por encima del nivel freático y a la influencia de los registros de lluvia. Los registros de presión del agua han ayudado a la identificación de las condiciones hidrogeológicas de la ladera. El modelo acoplado ha servido para calcular las deformaciones de la ladera y el cambio de la seguridad con el tiempo, integrando también los datos reales de lluvia. La comparación entre valores medidos y calculados ilustra la naturaleza de la inestabilidad de la ladera y las complejas relaciones que se establecen entre factores mecánicos e hidráulicos.
Safety factors for kinematically admissible failure mechanisms in jointed rock masses have been d... more Safety factors for kinematically admissible failure mechanisms in jointed rock masses have been defined with linear and nonlinear failure criteria for rock discontinuities. Data required to compute these safety factors are obtained by means of two finite element analyses of the effects of selfweight and external (structural) loading, respectively. Both types of analysis are closely linked since they share a common geometry. Joint elements are used to simulate the behaviour of rock discontinuities. If kinematically admissible mechanisms are possible under field conditions, the finite element mesh should also allow them to develop. Different aspects of the methodology have been illustrated through the safety evaluation of a 150m high arch dam and its foundation in fractured cretaceous limestone. Special attention has been paid to the modelling of a realistic geometry including three-dimensional rock blocks and discontinuities. The paper discusses the effect of initial state of stress, the evolution of safety as the external load increases and the relation between the defined safety factors. It also provides practical guidelines for conducting this type of analysis in complex situations.
Abstract: The paper presents general conclusions derived from a two dimensional unsaturated flow ... more Abstract: The paper presents general conclusions derived from a two dimensional unsaturated flow analysis coupled with a slope stability evaluation using limit equilibrium analysis. The change in strength is taken into account by means of a linear increment of ...
... 10). Beyond full saturation, the air pressure is essentially controlled by Henry&... more ... 10). Beyond full saturation, the air pressure is essentially controlled by Henry's law and the (slow) air diffusion process. ... The consideration of natural anisotropy and mechanical effects enhances the development of preferential paths for gas migration. ...
2020 IEEE Congreso Bienal de Argentina (ARGENCON)
Uno de los equipamientos más importantes de un laboratorio de alta tensión es el Equipo para Ensa... more Uno de los equipamientos más importantes de un laboratorio de alta tensión es el Equipo para Ensayos en Alta Tensión en Corriente Alterna a Frecuencia Industrial. Siendo su Unidad de Comando el elemento que más sufre el paso del tiempo ya que su tecnología se vuelve obsoleta, su reemplazo se convierte en prioritario. Con el propósito de aportar una solución eficiente y de bajo costo a este problema, evitando reemplazar la unidad de comando con tecnología actualizada, se puede concebir la posibilidad de eliminar físicamente dicho componente y emplear un programa de computadora especializado que realice la misma función. Este trabajo describe un programa como el citado, desarrollado bajo la plataforma LabVIEW, la cual ofrece muchas prestaciones, lo que permite no sólo realizar las funciones inherentes de la unidad de comando sino también introducir mejoras tanto en la seguridad de equipamientos y personas como en las técnicas de medición en alta tensión.
Se han investigado, mediante ensayos de laboratorio, las características de hidratación de mezcla... more Se han investigado, mediante ensayos de laboratorio, las características de hidratación de mezclas expansivas constituidas por una matriz de polvo arcilloso y agregados (pastillas de pequeño tamaño) de arcilla de alta densidad. Estas mezclas se han propuesto como material de relleno para aislar residuos potencialmente contaminantes del medio geológico que los rodea. Se ha simulado el comportamiento de este material de relleno bajo las condiciones existentes "in situ" mediante un análisis hidro-mecánico acoplado. En el análisis, el relleno se caracterizó de acuerdo con los resultados del programa de ensayos de laboratorio.Postprint (published version
Revista de Geología Aplicada a la Ingeniería y al Ambiente, 2015
El artículo analiza el desarrollo de flujo preferencial en pilas de lixiviación debido a la heter... more El artículo analiza el desarrollo de flujo preferencial en pilas de lixiviación debido a la heterogeneidad del mineral apilado. La heterogeneidad del material se describe mediante campos de permeabilidades aleatorios que aumentan la conectividad de los poros, con una media constante y una función de covariancia que depende del vector distancia relativa entre dos puntos arbitrarios. Puesto que los datos relativos a la variabilidad del material a pequeña escala es muy limitada, se mantiene una estrecha relación con los datos macroscópicos promedio medidos (homogéneo). Una vez definido el modelo de suelo heterogéneo, se utiliza un código termo-hidro-mecánico acoplado de propósito general para realizar el análisis. El mineral está inicialmente en estado no saturado y se simula el riego de la pila a una tasa determinada. Las características geotécnicas del material son representativas del mineral
A set of subroutines have been developed, in order to min1mlze the CPO time and storinq requireme... more A set of subroutines have been developed, in order to min1mlze the CPO time and storinq requirements in processinq block matrix products using non zero elements of each block matrix or non zero rows (columns). Comparation is set among product of blocks considered as sparse matrixes (column matrixes) or complete matrixes. Advantajes are ahown by results been obtained, in using developed techniques.
Se han investigado, mediante ensayos de laboratorio, las caracteristicas de hidratacion de mezcla... more Se han investigado, mediante ensayos de laboratorio, las caracteristicas de hidratacion de mezclas expansivas constituidas por una matriz de polvo arcilloso y agregados (pastillas de pequeno tamano) de arcilla de alta densidad. Estas mezclas se han propuesto como material de relleno para aislar residuos potencialmente contaminantes del medio geologico que los rodea. Se ha simulado el comportamiento de este material de relleno bajo las condiciones existentes "in situ" mediante un analisis hidro-mecanico acoplado. En el analisis, el relleno se caracterizo de acuerdo con los resultados del programa de ensayos de laboratorio. Hydration characteristics of an expansive mixture of compacted clay matrix and high density pellets ha ve been investigated by means of laboratory tests. These mixtures are proposed as a suitable barrier material to isolate hazardous wastes from the surrounding geological environment. The behaviour of this material under conditions prevailing "in situ" has been simulated by means of a coupled flow-deformation analysis. The backfill was characterized according to the results of the laboratory tests program.
Engineering Geology, 2002
Preferential paths are often reported in connection with gas breakthrough experiments. These pref... more Preferential paths are often reported in connection with gas breakthrough experiments. These preferential paths may be explained, in a deformable soil skeleton, by the action of pressurised gas along a natural path. A natural path is defined in a spatially heterogeneous material by a set of connected spots of higher gas permeability. Along this path the soil will experience a marked desaturation and gas permeability will increase fast. The paper describes a procedure to simulate these effects. Soil heterogeneity is described by means of random fields, which describe the key soil properties for gas migration. Since actual data concerning soil variability at a small (sample) scale is very limited, a number of computer models of increased complexity have been developed. They maintain, however, a close relationship with the known macroscopic data of the average (homogeneous) sample. The effect of some hypothesis concerning the stochastic structure of soil variability and the role of the hydromechanical coupling has also been explored. Once the heterogeneous soil model is defined, a general purpose code for Thermo-Hydro-Mechanical analysis is subsequently used to perform the analysis. The soil is initially saturated and a non-wetting phase (gas) is forced through the saturated mass either at constant pressure or at a constant flow rate. The results of the different analyses are compared in order to advance in the basic understanding of gas migration through clay barriers. Finally, a discussion of the relevance of soil heterogeneity, on the basis of the analysis performed, is presented.
La distribucion espacial de la conductividad hidraulica es una de las propiedades que mas influye... more La distribucion espacial de la conductividad hidraulica es una de las propiedades que mas influye sobre el flujo de liquido de solucion extractiva, a traves de una pila de lixiviacion de minerales. En este trabajo se presenta una metodologia basada en tecnicas geoestadisticas y geofisicas para determinar la distribucion espacial de la conductividad hidraulica en una pila de lixiviacion de minerales. El estudio se realiza con la informacion proporcionada por perfiles geofisicos realizados en la pila de lixiviacion de minerales del Proyecto Minero Gualcamayo, ubicado en el departamento Jachal de la provincia de San Juan. La variable proporcionada por la geofisica es la resistividad electrica. El analisis estadistico y geoestadistico de esta propiedad permite tanto estimar valores de resistividad electrica en unidades volumetricas, como la varianza del error, que da una idea de la precision y el grado de incertidumbre en la estimacion. De esta forma, se obtiene un modelo matematico de ...
En este trabajo se analiza el comportamiento de aberturas subterraneas mediante el empleo de un m... more En este trabajo se analiza el comportamiento de aberturas subterraneas mediante el empleo de un modelo en elementos finitos bidimensionales (2D) no lineal (elasto-plastico), con ley de fluencia de Mohr-Coulomg. En primer lugar se estudia una galeria aislada de acceso a una mina con seccion transversal circular o abovedada. A continuacion se comprueba el diseno del pilar entre dos galerias adyacentes y paralelas. El grado de seguridad del diseno se determina en funcion de un coeficiente de seguridad frente a la plastificacion.
The option of the disposal of radioactive waste in a deep clay layer is actually studied in Belgi... more The option of the disposal of radioactive waste in a deep clay layer is actually studied in Belgium, France, Spain and Netherlands. Immediately after closure and sealing of a geological radioactive waste repository a range of gases will be generated. Due to the low permeability of the clay materials these gases cannot easily escape. This can lead to an increase in pressure in the repository and to the creation of preferential gas pathways. In this paper, as a first step towards the development of computational techniques to handle flow of gas through compacted and natural clays, and to advance in the basic understanding of the gas migration issues associated with repository safety, the capabilities of a general code for coupled thermo-hydro-mechanical analysis have been explored. Some laboratory gas injection experiments carried out on natural clay samples have been selected in order to compare model computations with measured specimen of natural clay performance. The results show t...
Engineering Geology, 2002
Preferential paths are often reported in connection with gas breakthrough experiments. These pref... more Preferential paths are often reported in connection with gas breakthrough experiments. These preferential paths may be explained, in a deformable soil skeleton, by the action of pressurised gas along a natural path. A natural path is defined in a spatially heterogeneous material by a set of connected spots of higher gas permeability. Along this path the soil will experience a marked desaturation and gas permeability will increase fast. The paper describes a procedure to simulate these effects. Soil heterogeneity is described by means of random fields, which describe the key soil properties for gas migration. Since actual data concerning soil variability at a small (sample) scale is very limited, a number of computer models of increased complexity have been developed. They maintain, however, a close relationship with the known macroscopic data of the average (homogeneous) sample. The effect of some hypothesis concerning the stochastic structure of soil variability and the role of the...
BACCHUS2 in situ isothermal wetting experiment has been analysed by means of a coupled flowdeform... more BACCHUS2 in situ isothermal wetting experiment has been analysed by means of a coupled flowdeformation approach. Backfill material, a mixture of Boom clay powder and high density pellets, has been extensively tested in the laboratory in order to determine its hydraulic and mechanical properties. Parameters of constitutive equations were derived from this experimental data base. Two mechanical constitutive models have been used in the simulation of the 'in situ' experiment: a state surface approach and an elastoplastic model. Calculations have shown several features of the hydration process which help to understand the behaviour of expansive clay barriers. Predictions using both models have been compared with each other and with actual measurement records. This has allowed a discussion of the comparative mertis of both approaches and the identification of some critical parameters of backfill behaviour. Overall agreement between calculations and field measurements is encouraging and shows the potential of the methods developed to model the behaviour of engineered clay barriers in the context of nuclear waste disposal.
The behaviour of an instrumented unstable slope in a profile of weathered overconsolidated clay h... more The behaviour of an instrumented unstable slope in a profile of weathered overconsolidated clay has been analysed. Available field investigation data and laboratory tests were integrated in a coupled hydromechanical model of the slope. Particular attention was given to the unsaturated soil conditions above the water table and to the influence of the rainfall record. Recorded pore-water pressures helped to identify the hydrogeological conditions of the slope. The coupled model was used to compute slope deformations and the variation of safety with time. Actual rainfall records were also integrated into the analysis. Comparison of measurements and calculations illustrate the nature of the slope instability and the complex relationships between mechanical and hydraulic factors. Résumé Une pente instable dans un profil d'argile altérée sur-consolidée a été instrumentée et son comportement a été analysé. Des données disponibles obtenues lors d'étude sur le terrain et des essais en laboratoire ont été intégrés dans un modèle couplé hydromécanique de la pente. Une attention particulière a été portée aux conditions du sol non saturé au-dessus de la nappe et à l'influence de la succession de pluies. Les pressions enregistrées de l'eau dans les pores ont permis d'identifier les conditions hydrogéologiques de la pente. Le modèle couplé a été utilisé pour calculer les déformations de la pente et la variation de sécurité au cours du temps. Les enregistrement de pluies réelles ont été également intégrés à l'analyse. La comparaison des mesures aux calculs illustre la nature de l'instabilité de la pente et les relations complexes entre les facteurs mécaniques et hydrauliques. Resumen Se ha analizado el comportamiento de una ladera instable que fue instrumentada en un perfil de arcillas meteorizadas sobreconsolidadas. Se ha integrado los datos disponibles de investigaciones de campo y ensayos de laboratorio en un modelo hidromecánico acoplado de la ladera, prestando una atención especial a las condiciones del suelo no saturado por encima del nivel freático y a la influencia de los registros de lluvia. Los registros de presión del agua han ayudado a la identificación de las condiciones hidrogeológicas de la ladera. El modelo acoplado ha servido para calcular las deformaciones de la ladera y el cambio de la seguridad con el tiempo, integrando también los datos reales de lluvia. La comparación entre valores medidos y calculados ilustra la naturaleza de la inestabilidad de la ladera y las complejas relaciones que se establecen entre factores mecánicos e hidráulicos.
Safety factors for kinematically admissible failure mechanisms in jointed rock masses have been d... more Safety factors for kinematically admissible failure mechanisms in jointed rock masses have been defined with linear and nonlinear failure criteria for rock discontinuities. Data required to compute these safety factors are obtained by means of two finite element analyses of the effects of selfweight and external (structural) loading, respectively. Both types of analysis are closely linked since they share a common geometry. Joint elements are used to simulate the behaviour of rock discontinuities. If kinematically admissible mechanisms are possible under field conditions, the finite element mesh should also allow them to develop. Different aspects of the methodology have been illustrated through the safety evaluation of a 150m high arch dam and its foundation in fractured cretaceous limestone. Special attention has been paid to the modelling of a realistic geometry including three-dimensional rock blocks and discontinuities. The paper discusses the effect of initial state of stress, the evolution of safety as the external load increases and the relation between the defined safety factors. It also provides practical guidelines for conducting this type of analysis in complex situations.