Desarrollo de una herramienta completa de análisis y evaluación de riesgos en seguridad de presas

En los últimos años, se ha producido en el panorama internacional un acercamiento del campo de la seguridad de presas hacia las metodologías basadas en riesgo, en las que se combina la probabilidad de ocurrencia de eventos indeseados y sus consecuencias asociadas. Este acercamiento se comprueba por ejemplo en la publicación de un boletín de la Comisión Internacional de Grandes Presas (ICOLD) dedicado exclusivamente al tema y en que una de las sesiones del último Congreso Internacional de Grandes presas estuviese dedicada a ello. En cuanto a las realizaciones de análisis concretos, estas han variado desde las más simplificadas y cualitativas hasta aplicaciones cuantitativas completas. Ante este panorama, el principal objetivo del presente trabajo es desarrollar una herramienta completa que permita realizar análisis de riesgos sobre cualquier presa o sistema de presas. En base a ello, el trabajo está dividido en cinco partes, que se resumen a continuación. La primera parte presenta los fundamentos teóricos del Análisis de Riesgo y trata de manera sistemática cada una de las variables que forman parte de un modelo de riesgo y las relaciones existentes entre ellas. A cada una de ellas se dedica un capítulo en el que se revisa el estado del arte en cuanto a su modelación, aportando también los conocimientos y visiones que se han ganado a lo largo del desarrollo de este trabajo. Esta parte del trabajo tiene asimismo una vocación de guía para la realización de Análisis de Riesgo. Por ello, se propone también un procedimiento general para llevar a cabo Análisis de Riesgo y se incluye un capítulo en el que se repasan los principales criterios de tolerabilidad de riesgo existentes a nivel internacional. En la segunda parte se desarrolla una conceptualización de los modelos de riesgo suficientemente general como para poder representar cualquier tipo de modelo de riesgo que se pueda emplear en seguridad de presas, pero también suficientemente intuitiva y compacta como para sSerrano Lombillo, AJ. (2011). Desarrollo de una herramienta completa de análisis y evaluación de riesgos en seguridad de presas [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/11400Palanci

Dealing with epistemic uncertainty in risk-informed decision making for dam safety management

[EN] In recent years, the application of risk analysis to inform dam safety governance has increased significantly. In this framework, considering explicitly and independently both natural and epistemic uncertainty in quantitative risk models allows to understand the sources of uncertainty in risk results and to estimate the effect of actions, tests, and surveys to reduce epistemic uncertainty. In this paper, Indexes of Coincidence are proposed to analyze the effect of epistemic uncertainty in the prioritization of investments based on risk results, which is the key issue in this paper. These indexes allow consideration of the convenience of conducting additional uncertainty reduction actions. These metrics have been applied to the prioritization of risk reduction measures for four concrete gravity dams in Spain. Results allow for a better understanding of how epistemic uncertainty of geotechnical resistance parameters influence risk-informed decision making. The proposed indexes are also useful for probabilistic risk analyses of other civil engineering structures with high epistemic uncertainty environments, since they analyze whether existing uncertainty could have an impact on decision making, outlining the need for extra studies, surveys and tests.Morales Torres, A.; Escuder Bueno, I.; Serrano Lombillo, AJ.; Castillo-Rodríguez, J. (2019). Dealing with epistemic uncertainty in risk-informed decision making for dam safety management. Reliability Engineering & System Safety. 191. https://doi.org/10.1016/j.ress.2019.106562S19

The suitability of risk reduction indicators to inform dam safety management

[EN] Risk analysis can provide very suitable and useful information to manage the safety of critical civil infrastructures. Indeed, results of quantitative risk models can be used to inform prioritisation of safety investments on infrastructures' assets and portfolios. In order to inform this prioritisation, a series of risk reduction indicators can be used. This paper reviews existing indicators for dam safety, tracks how equity and efficiency principles are captured, propose additional indicators and provides insights into how tolerability guidelines and benefit-cost analysis can also play a role in decision-making. All reviewed, analysed and/or combined indicators are later applied in a case study, a portfolio of 27 dams where 93 structural and non-structural investments are prioritised. The case study shows that prioritisation sequences based on risk model results provide suitable and useful information, acknowledging that other concerns may be conditioning decision-making processes. With the results of the case study, a full comparison between all studied risk reduction indicators is made, and three indexes are calculated for all of them to measure how close they are to a theoretical best.The Spanish Ministry of Economy and Competitiveness (MINECO) has supported the work described in this paper through the research project entitled IPRESARA (Incorporating man-made risk components into general dam risk management [BIA 2010-17852]) within the period 2011-2013 and the project INICIA (Methodology for assessing investments on water cycle infrastructures informed on risk and energy efficiency indicators [BIA 2013-48157-C2-1-R]) within the period 2014-2016.Morales Torres, A.; Serrano Lombillo, AJ.; Escuder Bueno, I.; Altarejos García, L. (2016). The suitability of risk reduction indicators to inform dam safety management. Structure and Infrastructure Engineering. 12(11):1465-1476. https://doi.org/10.1080/15732479.2015.1136830S146514761211Ayyub, B. M., McGill, W. L., & Kaminskiy, M. (2007). Critical Asset and Portfolio Risk Analysis: An All-Hazards Framework. Risk Analysis, 27(4), 789-801. doi:10.1111/j.1539-6924.2007.00911.xBaecher, G. B., Paté, M. E., & De Neufville, R. (1980). Risk of dam failure in benefit-cost analysis. Water Resources Research, 16(3), 449-456. doi:10.1029/wr016i003p00449Bohnenblust, H. (1998). Risk-Based Decision Making in the Transportation Sector. Quantified Societal Risk and Policy Making, 132-153. doi:10.1007/978-1-4757-2801-9_14Bottelberghs, P. . (2000). Risk analysis and safety policy developments in the Netherlands. Journal of Hazardous Materials, 71(1-3), 59-84. doi:10.1016/s0304-3894(99)00072-2De Blaeij, A., Florax, R. J. G. ., Rietveld, P., & Verhoef, E. (2003). The value of statistical life in road safety: a meta-analysis. Accident Analysis & Prevention, 35(6), 973-986. doi:10.1016/s0001-4575(02)00105-7Ellingwood, B. R. (2005). Risk-informed condition assessment of civil infrastructure: state of practice and research issues. Structure and Infrastructure Engineering, 1(1), 7-18. doi:10.1080/15732470412331289341Figueira, J., Greco, S., & Ehrogott, M. (2005). Multiple Criteria Decision Analysis: State of the Art Surveys. International Series in Operations Research & Management Science. doi:10.1007/b100605Jonkman, S. N., Jongejan, R., & Maaskant, B. (2010). The Use of Individual and Societal Risk Criteria Within the Dutch Flood Safety Policy-Nationwide Estimates of Societal Risk and Policy Applications. Risk Analysis, 31(2), 282-300. doi:10.1111/j.1539-6924.2010.01502.xJonkman, S. N., van Gelder, P. H. A. J. M., & Vrijling, J. K. (2003). An overview of quantitative risk measures for loss of life and economic damage. Journal of Hazardous Materials, 99(1), 1-30. doi:10.1016/s0304-3894(02)00283-2Joshi, N. N., & Lambert, J. H. (2007). Equity Metrics With Risk, Performance, and Cost Objectives for the Prioritization of Transportation Projects. IEEE Transactions on Engineering Management, 54(3), 539-547. doi:10.1109/tem.2007.900790Kabir, G., Sadiq, R., & Tesfamariam, S. (2013). A review of multi-criteria decision-making methods for infrastructure management. Structure and Infrastructure Engineering, 10(9), 1176-1210. doi:10.1080/15732479.2013.795978Kaplan, S. (1997). The Words of Risk Analysis. Risk Analysis, 17(4), 407-417. doi:10.1111/j.1539-6924.1997.tb00881.xKeeney, R. L., & Raiffa, H. (1993). Decisions with Multiple Objectives. doi:10.1017/cbo9781139174084Khadam, I. M., & Kaluarachchi, J. J. (2003). Multi-criteria decision analysis with probabilistic risk assessment for the management of contaminated ground water. Environmental Impact Assessment Review, 23(6), 683-721. doi:10.1016/s0195-9255(03)00117-3Lutter, R., Morrall, J. F., & Viscusi, W. K. (1999). THE COST-PER-LIFE-SAVED CUTOFF FOR SAFETY-ENHANCING REGULATIONS. Economic Inquiry, 37(4), 599-608. doi:10.1111/j.1465-7295.1999.tb01450.xRamsberg, J. A. L., & Sjoberg, L. (1997). The Cost-Effectiveness of Lifesaving Interventions in Sweden. Risk Analysis, 17(4), 467-478. doi:10.1111/j.1539-6924.1997.tb00887.xSaaty, T. L. (1988). What is the Analytic Hierarchy Process? Mathematical Models for Decision Support, 109-121. doi:10.1007/978-3-642-83555-1_5Stewart, M. G., & Mueller, J. (2008). A risk and cost-benefit assessment of United States aviation security measures. Journal of Transportation Security, 1(3), 143-159. doi:10.1007/s12198-008-0013-0Viscusi, W. K., & Aldy, J. E. (2003). Journal of Risk and Uncertainty, 27(1), 5-76. doi:10.1023/a:1025598106257Vrijling, J. (1995). A framework for risk evaluation. Journal of Hazardous Materials, 43(3), 245-261. doi:10.1016/0304-3894(95)91197-vYamano, N., & Ohkawara, T. (2000). The Regional Allocation of Public Investment: Efficiency or Equity? Journal of Regional Science, 40(2), 205-229. doi:10.1111/0022-4146.0017

A new risk reduction indicator for dam safety management combining efficiency and equity principles

[EN] Large dams are critical infrastructures whose failure could produce high economic and social consequences. Risk analysis has been shown to be a suitable methodology to assess these risks and to inform dam safety management. In this sense, risk reduction indicators are a useful tool to manage risk results, yielding potential prioritisation sequences of investments in dams portfolios. Risk management is usually informed by two basic principles: efficiency and equity. These two principles many times conflict, requiring a tradeoff between optimising the expenditures and providing a high level of protection to all individuals. In this paper, the risk reduction indicator Equity Weighted Adjusted Cost per Statistical Life Saved (EWACSLS) is presented. This indicator allows obtaining prioritisation sequences of investments while maintaining an equilibrium between equity and efficiency principles. In order to demonstrate its usefulness, it has been applied in a real-world case study, a portfolio of 27 dams where 93 structural and non-structural investments are prioritised. The EWACSLS indicator is analysed in detail and its results are compared with other existing risk reduction indicators, showing its flexibility and how it can be a very well balanced indicator for the purpose of prioritisation of risk reduction measures.This paper was published with the support of the research project ‘INICIA’ (Methodology for Assessing Investments on Water Cycle Infrastructures informed on Risk and Energy Efficiency Indicators, BIA2013-48157-C2- 1-R, 2014-2016); co-funded by the Spanish Ministry of Economy and Competitiveness ‘Ministerio de Economía y Competitividad’ (Programa Estatal de Investigación, Desarrollo e Innovación Orientada a los Retos de la Sociedad); and the European Regional Development Fund (ERDF).Serrano Lombillo, AJ.; Morales Torres, A.; Escuder Bueno, I.; Altarejos García, L. (2016). A new risk reduction indicator for dam safety management combining efficiency and equity principles. Structure and Infrastructure Engineering. 13(9):1157-1166. https://doi.org/10.1080/15732479.2016.1245762S11571166139Blackorby, C., & Donaldson, D. (1977). Utility vs equity. Journal of Public Economics, 7(3), 365-381. doi:10.1016/0047-2727(77)90055-xBleichrodt, H. (1997). Health utility indices and equity considerations. Journal of Health Economics, 16(1), 65-91. doi:10.1016/s0167-6296(96)00508-5De Blaeij, A., Florax, R. J. G. ., Rietveld, P., & Verhoef, E. (2003). The value of statistical life in road safety: a meta-analysis. Accident Analysis & Prevention, 35(6), 973-986. doi:10.1016/s0001-4575(02)00105-7(2001). The Economic Journal, 111(471). doi:10.1111/ecoj.2001.111.issue-471Dolan, P. (1998). The measurement of individual utility and social welfare. Journal of Health Economics, 17(1), 39-52. doi:10.1016/s0167-6296(97)00022-2Dundar, H. (1999). Equity, quality and efficiency effects of reform in Turkish higher education. Higher Education Policy, 12(4), 343-366. doi:10.1016/s0952-8733(99)00016-1Jonkman, S. N., van Gelder, P. H. A. J. M., & Vrijling, J. K. (2003). An overview of quantitative risk measures for loss of life and economic damage. Journal of Hazardous Materials, 99(1), 1-30. doi:10.1016/s0304-3894(02)00283-2Joshi, N. N., & Lambert, J. H. (2007). Equity Metrics With Risk, Performance, and Cost Objectives for the Prioritization of Transportation Projects. IEEE Transactions on Engineering Management, 54(3), 539-547. doi:10.1109/tem.2007.900790(1997). Risk Analysis, 17(4). doi:10.1111/risk.1997.17.issue-4Khadam, I. M., & Kaluarachchi, J. J. (2003). Multi-criteria decision analysis with probabilistic risk assessment for the management of contaminated ground water. Environmental Impact Assessment Review, 23(6), 683-721. doi:10.1016/s0195-9255(03)00117-3Linnerooth-Bayer, J., & Amendola, A. (2000). Global Change, Natural Disasters and Loss-sharing: Issues of Efficiency and Equity. Geneva Papers on Risk and Insurance - Issues and Practice, 25(2), 203-219. doi:10.1111/1468-0440.00060(1999). Economic Inquiry, 37(4). doi:10.1111/ecin.1999.37.issue-4Morales-Torres, A., Serrano-Lombillo, A., Escuder-Bueno, I., & Altarejos-García, L. (2016). The suitability of risk reduction indicators to inform dam safety management. Structure and Infrastructure Engineering, 1-12. doi:10.1080/15732479.2015.1136830(2011). Risk Analysis, 31(6). doi:10.1111/risk.2011.31.issue-6Stewart, M. G., & Mueller, J. (2008). A risk and cost-benefit assessment of United States aviation security measures. Journal of Transportation Security, 1(3), 143-159. doi:10.1007/s12198-008-0013-0Yamano, N., & Ohkawara, T. (2000). The Regional Allocation of Public Investment: Efficiency or Equity? Journal of Regional Science, 40(2), 205-229. doi:10.1111/0022-4146.0017

Inclusión en modelos de riesgo de presas de una metodología de estimación hidrológica basada en técnicas de Monte Carlo

En este estudio se aplica una metodología de obtención de las leyes de frecuencia derivadas (de caudales máximo vertidos y niveles máximos alcanzados) en un entorno de simulaciones de Monte Carlo, para su inclusión en un modelo de análisis de riesgo de presas. Se compara su comportamiento respecto del uso de leyes de frecuencia obtenidas con las técnicas tradicionalmente utilizadas

Methodology for the Calculation of Annualized Incremental Risks in Systems of Dams

In the past few years, the field of dam safety has approached risk informed methodologies throughout the world and several methodologies and programs are appearing to aid in the systematization of the calculations. The most common way of implementing these calculations is through the use of event trees, computing event probabilities, and incremental consequences. This methodology is flexible enough for several situations, but its generalization to the case of systems of several dams is complex and its implementation in a completely general calculation methodology presents some problems. Retaining the event tree framework, a new methodology is proposed to calculate incremental risks. The main advantage of this proposed methodology is the ease with which it can be applied to systems of several dams: with a single risk model that describes the complete system and with a single calculation the incremental risks of the system can be obtained, being able to allocate the risk of each dam and of each failure mode. The article shows how both methodologies are equivalent and also applies them to a case study

The value of integrating information from multiple hazards for flood risk analysis and management

This article presents a methodology for estimating flood risk in urban areas integrating pluvial flooding, river flooding and failure of both small and large dams. The first part includes a review of basic concepts on flood risk analysis, evaluation and management. Flood risk analyses may be developed at local, regional and national level, however a general methodology to perform a quantitative flood risk analysis including different flood hazards is still required. The second part describes the proposed methodology, which presents an integrated approach - combining pluvial, river flooding and flooding from dam failure, as applied to a case study: an urban area located downstream of a dam under construction. The methodology enhances the approach developed within the SUFRI project ("Sustainable Strategies of Urban Flood Risk Management to cope with the residual risk", 2009-2011). This article also shows how outcomes from flood risk analysis provide better and more complete information to inform authorities, local entities and the stakeholders involved in decision-making with regard to flood risk management.The work presented in this paper has been supported by the Spanish Ministry of Science and Innovation (MICINN) through the grant to the budget of the SUFRI project (EUI 2008-03933) and of the iPRESARA project (BIA 2010-17852).Castillo Rodríguez, JT.; Escuder Bueno, I.; Altarejos García, L.; Serrano Lombillo, AJ. (2014). The value of integrating information from multiple hazards for flood risk analysis and management. Natural Hazards and Earth System Sciences. 14(2):379-400. doi:10.5194/nhess-14-379-2014S379400142ANCOLD: Guidelines on Risk Assessment, Australian National Committee on Large Dams Inc., Australia, 2003.Bowles, D. 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T., Zechner, S., Jöbstl, C., Perales-Momparler, S., and Petaccia, G.: A quantitative flood risk analysis methodology for urban areas with integration of social research data, Nat. Hazards Earth Syst. Sci., 12, 2843–2863, https://doi.org/10.5194/nhess-12-2843-2012, 2012.Evans, A. W. and Verlander, N. Q.: What is wrong with criterion FN lines for judging the tolerability of risk, Risk Analysis, 17, 157–168, 1997.Frey, H. C. and Patil, S. 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Hazards, 34, 151–175, 2005.Jonkman, S. N.: Loss of life estimation in flood risk assessment, Ph.D. thesis, Delft University of Technology, Delft, the Netherlands, 2007.Jonkman, S. N., Maaskant, B., Boyd, E., and Levitan, M. L.: Loss of Life Caused by the Flooding of New Orleans After Hurricane Katrina: Analysis of the Relationship Between Flood Characteristics and Mortality, Risk Analysis, 29, 676–98, https://doi.org/10.1111/j.1539-6924.2008.01190.x, 2009.Jonkman, S. N., Jongejan, R., and Maaskant, B.: The Use of Individual and Societal Risk Criteria Within the Dutch Flood Safety Policy – Nationwide Estimates of Societal Risk and Policy Applications, Risk Analysis, 31, 282–300, https://doi.org/10.1111/j.1539-6924.2010.01502.x, 2011.Klijn, F., Samuels, P., and van Os, D.: Towards Flood Risk Management in the EU: State of affairs with examples from various European countries, Int. J. 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H., and Viavattene, C.: Review article: Assessing the costs of natural hazards – state of the art and knowledge gaps, Nat. Hazards Earth Syst. Sci., 13, 1351–1373, https://doi.org/10.5194/nhess-13-1351-2013, 2013.Munger, D. F., Bowles, D. S., Boyer, D. D., Davis, D. W., Margo, D. A., Moser, D. A., and Regan, P. J.: Interim tolerable risk guidelines for US Army Corps of Engineers Dams, USSD Conference, 20–24 April 2009, Nashville, Tennessee, 2009.Pappenberger, F., Beven, K. J., Ratto, M., and Matgen, P.: Multi-method global sensitivity analysis of flood inundation models, Adv. Water Resour., 31, 1–14, 2008.Parker, D., Tunstall, S., and Wilson, T.: Socio-economic benefits of flood forecasting and warning, Flood Hazard Research Centre, Middlesex University, Queensway, Enfield, London, UK, 2005.Pelling, M.: The vulnerability of cities – Natural disasters and social resilience, Earthscan Publications Ltd., London, UK, 2003.Penning-Rowsell, E., Chatterton, J. B., and Parker, D.: The Effect of Flood Warnings on Flood Damage Reduction, Middlesex Polytechnic Flood Hazard Research Project, Flood Hazard Research Centre, Middlesex University, Middleesex, UK, 1978.PGOU: Plan General de Ordenación Urbana, Urban General Plan, City of Benaguasil (Valencia), Benaguasil, Spain, 2009.Rackwitz, R.: Optimization and risk acceptability based on the Life Quality Index, Struct. Safety, 24, 297–331, 2002.Sanz-Jiménez, D., Escuder-Bueno, I., and Silva-Tulla, F.: Quantitative risk analysis for a dam under construction in Spain, Proc. of the 32nd Annual USSD Conference, 23–25 April 2012, United States Society on Dams, New Orleans, Louisiana, 2012.Schanze, J., Hutter, G., Olfert, A., Penning-Rowsell, E. C., Parker, D., Harries, T., Werritty, A., Nachtnebel, H., Holzmann, H., Neuhold, C., Meyer, V., Kuhlicke, C., Schildt, A., Jessel, B., and Königer, P.: FLOOD-ERA Joint Report, CRUE Research Report No. I-1: Systematisation, evaluation and context conditions of structural and non-structural measures for flood risk reduction, Project Contract No. ERAC-CT-2004-515742, CRUE Funding Initiative on Flood Risk Management Research, London, 2008.Serrano-Lombillo, A., Escuder-Bueno, I., de Membrillera-Ortuño, M. 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K.: Probabilistic design of water defence systems in The Netherlands, Reliabil. Eng. Syst. Safety, 74, 337–344, 2001.WMO/GWP: Urban flood risk management, A Tool for Integrated Flood Management, World Meteorological Organization (WNO) & Global Water Partnership (GWP), Associated Programme on Flood Management, Geneva, Switzerland, 2008

Assessing the impact of uncertainty on flood risk estimates with reliability analysis using 1-D and 2-D hydraulic models

This paper addresses the use of reliability techniques such as Rosenblueth¿s Point-Estimate Method (PEM) as a practical alternative to more precise Monte Carlo approaches to get estimates of the mean and variance of uncertain flood parameters water depth and velocity. These parameters define the flood severity, which is a concept used for decision-making in the context of flood risk assessment. The method proposed is particularly useful when the degree of complexity of the hydraulic models makes Monte Carlo inapplicable in terms of computing time, but when a measure of the variability of these parameters is still needed. The capacity of PEM, which is a special case of numerical quadrature based on orthogonal polynomials, to evaluate the first two moments of performance functions such as the water depth and velocity is demonstrated in the case of a single river reach using a 1-D HEC-RAS model. It is shown that in some cases, using a simple variable transformation, statistical distributions of both water depth and velocity approximate the lognormal. As this distribution is fully defined by its mean and variance, PEM can be used to define the full probability distribution function of these flood parameters and so allowing for probability estimations of flood severity. Then, an application of the method to the same river reach using a 2-D Shallow Water Equations (SWE) model is performed. Flood maps of mean and standard deviation of water depth and velocity are obtained, and uncertainty in the extension of flooded areas with different severity levels is assessed. It is recognized, though, that whenever application of Monte Carlo method is practically feasible, it is a preferred approach.This work is part of the research project "Incorporacion de los componentes de riesgo antropico a los sistemas de gestion integral de seguridad de presas y embalses" BIA2010-17852, funded by Spain's Ministerio de Ciencia e Innovacion and FEDER funds.Altarejos García, L.; Martínez Chenoll, ML.; Escuder Bueno, I.; Serrano Lombillo, AJ. (2012). Assessing the impact of uncertainty on flood risk estimates with reliability analysis using 1-D and 2-D hydraulic models. Hydrology and Earth System Sciences and Discussions. 16(7):1985-1994. https://doi.org/10.5194/hess-16-1895-2012S19851994167Aronica, G., Hankin, B., and Beven, K. J.: Uncertainty and equifinality in calibrating distributed roughness coefficients in a flood propagation model with limited data, Adv. 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Methodology for estimating the probability of failure by sliding in concrete gravity dams in the context of risk analysis

Dam safety based on risk analysis methodologies demand quantification of the risk of the dam-reservoir system. This means that, for a given initial state of the system, and for the several failure modes considered, it is necessary to estimate the probability of the load events and the conditional probability of response of the system for a given load event, as well as estimating the consequences on the environment for the obtained response of the system. The following paper focuses in the second of these probabilities, that is, quantifying the conditional probability of response of the system, for a given load event, and for the specific case of concrete gravity dams. Dam-reservoir systems have a complex behavior which has been tackled traditionally by simplifications in the formulation of the models and adoption of safety factors. The purpose of the methodology described in this paper is to improve the estimation of the conditional probability of response of the dam-reservoir system for concrete gravity dams, using complex behavior models based on numerical simulation techniques, together with reliability techniques of different levels of precision are applied, including Level 3 reliability techniques with Monte Carlo simulation. The paper includes an example of application of the proposed methodology to a Spanish concrete gravity dam, considering the failure mode of sliding along the rock-concrete interface. In the context of risk analysis, the results obtained for conditional probability of failure allow several conclusions related to their validity and safety implications that acquire a significant relevance due to the innovation of the study performedAltarejos García, L.; Escuder Bueno, I.; Serrano Lombillo, AJ.; Gómez De Membrillera Ortuño, M. (2012). Methodology for estimating the probability of failure by sliding in concrete gravity dams in the context of risk analysis. Structural Safety. 34(1):1-13. https://doi.org/10.1016/j.strusafe.2012.01.001S11334

Building fragility curves of sliding failure of concrete gravity dams integrating natural and epistemic uncertainties

[EN] The proposed procedure combines the concepts of the Electrical Power Research Institute (EPRI) guidelines to develop fragility curves for the nuclear industry with existing reliability techniques for computing fragility curves in the context of concrete dams engineering. The procedure has been applied to a dam to illustrate how it can be used in a real case in such a manner that fragility curves are obtained integrating natural and epistemic uncertainties without losing track of their separate contribution to risk results. (C) 2016 Elsevier Ltd. All rights reserved.This paper was published with the support of the research project "INICIA" (Methodology for Assessing Investments on Water Cycle Infrastructures informed on Risk and Energy Efficiency Indicators, BIA2013-48157-C2-1-R, 2014-2016), co-funded by the Spanish Ministry of Economy and Competitiveness "Ministerio de Economia y Competitividad" (Programa Estatal de Investigacion, Desarrollo e Innovation Orientada a los Retos de la Sociedad) and the European Regional Development Fund (ERDF).Morales Torres, A.; Escuder Bueno, I.; Altarejos García, L.; Serrano Lombillo, AJ. (2016). Building fragility curves of sliding failure of concrete gravity dams integrating natural and epistemic uncertainties. Engineering Structures. 125:227-235. https://doi.org/10.1016/j.engstruct.2016.07.006S22723512