Committee A: Computational aspects of analysis and design of dams

Transkript

1 Kommitté: Committee A: Computational aspects of analysis and design of dams ICOLDs Committee on computational aspects of analysis and design of dams har varit aktiv under återkommande tidsperioder sedan många år tillbaka. De två senaste aktiva perioderna är samt den nu pågående sedan Kommittén arbetar med att ta fram bulletiner och ordna Benchmark Workshop. Kommittén har gett ut 6 bulletiner varav Bulletin 122 Computational procedures for dam engineering Reliability and applicability, utgiven 2001 och Bulletin 155 Guidelines for Use of Numerical Models in Dam Engineering, utgiven 2012 är de senast färdigställda bulletinerna. Bulletin 122 innehåller en kritisk granskning av effektiviteten hos tillgängliga matematiska modeller för olika typer av dammar och problemställningar. Bulletinen visar också några av de referenstillämpningar som presenterades under de fyra första Benchmark workshops före Bulletin 155 presenterar allmänna rekommendationer för processer inom numeriska analysmetoder tillämpade på dammkonstruktioner vid nybyggnad. Bulletinen behandlar även tillämpning av numeriska analysmetoder på befintliga dammar med särskild hänsyn till uppgifter från mätning och övervakning. Kommittén har sedan 1991 anordnat 13 Benchmark Workshop. Den 13nde Benchmark Workshopen ägde rum i Lausanne, Schweiz, i september Workshopen innehöll 3 tema, nämligen 1. Theme A Concrete dam Seismic safety evaluation of a concrete dam based on guidelines 2. Theme B Fill dam Probability of failure of an embankment dam due to slope instability and overtopping 3. Theme C Open Safety evaluation of dams Nästa, d.v.s. den 14nde, Benchmark Workshop äger rum hösten Datum och organisatorsland bestäms vid kommitténs möte i maj Sverige ansöker om att få ordna workshop 14. Förordnandeperiod: Kommitténs ordförande: Ignacio Escuder Bueno, Spanien ny ordförande väljs vid mötet i maj 2016 Svensk delegat: Manouchehr Hassanzadeh, Sweco Energuide Manouchehr.Hassanzadeh@Sweco.se Kommitténs uppdrag: 1 Prepare recommendations on the role and capabilities of numerical models to deal with problems relevant to dams throughout their life cycle (design, construction, operation, maintenance, rehabilitation, etc.) 2 Organize Benchmark Workshops to compare numerical models between one another and/or with reference solution, including the dissemination and publication of results. 3 Prepare recommendations on how computational methods can be used to estimate risks and account for uncertainties inherent to dams. 4 Review and consolidate the state of the art on new probabilistic approaches to traditionally deterministic inputs and outcomes of numerical modelling. 1

2 5 Propose lines of research aiming at establishing valid numerical models for the solution of dam problems presently not amenable to reliable numerical treatment Lägesrapport 2015: Kommitté A hade ett möte i samband med ICOLD s 83rd Annual Meeting and 25th Congress June Stavanger - Norway. Vid mötet diskuterades kommitténs mål och arbetsuppgifter under de kommande åren, mötesprotokoll finns i Bilaga 1. Kommittén fortsätter arbetet med att sammanställa en bulletin med titeln Suit of numerical models for dam risk management. Man vill undersöka hur probabilistisk betraktelse av exempelvis materialegenskaper, belastningar, geometri, mm kan införas i numeriska modeller, hur utfallet blir jämfört med numerisk modellering baserad på det traditionella deterministiska betraktelsesättet samt hur de kan inkluderas i riskanalys av dammar. Arbetet med bulletin Non-linear modelling of concrete dams NLMCD fortsätter. Den svenska delegaten är sammankallande. Under 2015 hölls ett webbmöte och arbetet presenterades vid kommitté A:s möte i samband med ICOLD s årliga möte i Stavanger samt vid den 13nde Benchmark Workshop i Lausanne i september 2015, Bilaga 2. Det finns en RILEM kommitté som arbetar med AKR (Alkalikiselreaktioner), RILEM ASR Prognosis of deterioration and loss of serviceability in structures affected by alkali-silica reactions. Arbetet inkluderar även vattenkraftens betongkonstruktioner. Arbetet bedrivs inom 4 arbetsgrupper med varsin ledare. 1. WG-1 Material Testing (leaders: V. Saouma and A. Sellier) 2. WG-2 Numerical Modeling (Leaders: A. Sellier and V. Saouma) 3. WG-3 Monitoring (Leaders: L. Jacobs and P. Rivard) 4. WG-4 Large Scale Testing (Leaders: Y. Le Pape and Neb Orbovic) En svensk arbetsgrupp har bildats för att övervaka arbetet. Den svenska gruppen är organiserad enligt följande indelning och deltagare. 1. WG-1 Material Testing: Manouchehr Hassanzadeh (Swco- aktiv) och Jan Trägårdh (CBI - aktiv) 2. WG-2 Numerical Modeling: Richard Malm (KTH/Sweco - aktiv), Kamyab Zandi (CBI - stödjande), Tobias Gasch (Vattenfall - stödjande) Manouchehr Hassanzadeh (stödjande) 3. WG-3 Monitoring: Ali Farhang (Ramböll - aktiv), Richard Malm (stödjande), Tobias Gash (stödjande), Manouchehr Hassanzadeh (stödjande) Arbetet utförs i två etapper, varav i etapp 1 en state-of-the-art-report, som skall vara klar i juni 2015, tas fram. Etapp 2 börjar efter avslutat etapp 1. Manouchehr Hassanzadeh och Jan Trägårdh tog ansvaret att sammanställa en lägesrapport som beskriver olika provningsmetoder som används för prediktering av expansion av AKR skadade betongkonstruktioner. Lägesrapporten sammanställdes och presenterades vid ett möte i Paris Resultatet var mycket uppskattat så att ytterligare tre forskargrupper skickade sina metoder för att inkluderas i sammanställningen. Arbetet expanderade och krävde ytterligare insatser. En av V. Saoumas doktorander har hjälpt till och fortsatt med arbetet. Hassanzadehs och Trägårdhs arbete finansieras delvis av 2

3 Energiforsks Betongprogram Vattenkraft. En lägesrapport för det utförda kommittéarbetet förbereds för Betongprogrammet. Kommande aktiviteter 2016: Nästa kommittémöte äger rum i samband med ICOLD 84 th Annual Meeting May Johannesburg - South Africa. Svensk delegat deltar i mötet. Delegaten kommer att ansöka om att Sverige skall få anordna den 14nde Benchmark Workshopen hösten Delegaten är medförfattare i två artiklar som har skickats till ICOLD för att presenteras vid mötet i maj Arbetet med bulletinen Non-Linear Modelling of Concrete Dams kommer att fortsätta, tre webbmöten och ett fysiskt möte planeras för Arbetet med RILEMs ASR-kommitté fortsätter under Övrigt: Manouchehr Hassanzadeh, Stockholm

4 Bilaga 1 A p. 1 A) COMPUTATIONAL ASPECTS OF ANALYSIS AND DESIGN OF DAMS A) METHODES DE CALCULS POUR BARRAGES PROGRESS REPORT RAPPORT D ACTIVITÉ Meeting in Stavanger, 13 rd June 2015 Réunion à Stavanger, 13 juin 2015 MEMBERSHIP / LISTE DES MEMBRES MEETING / Réunion COUNTRIES PAYS MEMBERS MEMBRES Present Absent/Substitutes Spain ESCUDER Ignacio Chairman YES Italy MAZZA' G. Vice-C. YES Italy MEGHELLA M. Member YES Italy FANELLI M. Hon.Member NO France CARRERE A. Hon.Member NO Argentina RESTELLI F. Member NO Australia LOPEZ F. Member NO Malcolm Barker Austria ZENZ G. Member YES Canada CURTIS D. Member NO China CHEN S. Member YES Colombia MARULANDA C. Member YES Finland VARPASUO P. Member YES Form.Yug. Yugoslavia TANCEV L. Member NO France FROSSARD E. Member YES Germany BEETZ U. Member NO Greece DAKOULAS P. Member NO Iran GHAEMIAN M. Member NO Japan NOGUCHI Y. Member YES Norway ANDERSEN R. Member YES Romania POPOVICI A. Member NO Daniel Gaftoi Russia GLAGOVSKY V. Member YES Slovakia MINARIK M. Member NO Sweden HASSANZADEH M. Member YES GUNN R.M. Member NO Turkey OZEN O. Member NO Altug Akman United States MATHEU E. Member NO OBSERVERS: Salih Bilgin AKMAN, Miroslav Broucek, Kyrylo RYZHYKOV, Eehab Ahmed Badr-El-din Khalil

5 Bilaga 1 Committee A hold a Workshop on June 12, 2015, at Stavanger Forum from 10:00am to 10:45am, with more than 40 total attendees. It included a series of presentations linked to coming celebration of the XIII ICOLD Numerical Benchmark Workshop, to be hold in Lausanne,, September , following a tradition that lasts for more than 20 years (started in Bergamo, 1991). Namely: Overview of Committee A and Benchmark Workshops (BW) on Numerical Modelling of Dams by Guido Mazzà: Presentation of Theme A on Seismic safety evaluation of a concrete dam based on guidelines by Massimo Meghella Presentation of Theme B on Probability of failure of an embankment dam due to slope instability and overtopping by Ignacio Escuder Presentation of Theme C on Safety evaluation of dams by Guido Mazzà. Open discussion on capitalization of results and future initiatives On June 33, from 9am to 13pm the Committee A meeting included the following agenda items: A - p. 2 Welcome and review of last meeting (Bali 2014) minutes, recalling the fact that next year, in 2016, the Committee will have to propose another Benchmark Workshop, select a host, revisit the terms of reference and prepare an extension application. An in-depth presentation of the status of the coming Benchmark Workshop was given by Massimo Meghella, Guido Mazzà and Ignacio Escuder. It included expected participants (so far around 40 participants among the three Themes), organizational issues and practical and scientific challenges of the Themes. The presentation was followed by a very rich debate reflecting the interest and importance of the topics. On-going tasks. ü ü The discussion on numerical and computational needs with regard to risk analysis and assessment highlighted the fact that Lausanne is going to be the third Benchmark Workshop in which a risk analysis theme is addressed, and it closes a loop after dealing with failure risk of concrete dams (Valencia 2011), consequences (Graz 2013) and now failure risk of embankment dams (Lausanne 2015). It was decided to writhe a synthesis paper on the lessons learnt from the three events. Manouchehr.Hassanzadeh, in close cooperation with Massimo Meghella, presented significant advances on the guidelines on numerical non-linear analysis with emphasis on discontinuities of concrete dams, including a complete index and several contents. The group had a very fruitful discussion and several members of the committee committed to give further collaboration in order to have a first drafted document for next year. Following the open discussion on how to proceed to capitalize the results of XII BW held in Bali, task since then undertaken by Önder Özen, it was agreed to finish the task within next year, so that it can be presented either at the South Africa Annual Meeting (June 2016) or the Antalya European Club of ICOLD Symposium (October 2016)

6 ICOLD BULLETIN N XXX NON-LINEAR MODELLING OF CONCRETE DAMS NLMCD M. Hassanzadeh & M Meghella

7 Numerical hot issues identified by the participants Committee A meeting Seattle, August, 2013 Concrete dams 1- Dynamic behaviour of abutments Crude methods for stability 2009 workshop Russell Gunn 2- Foundation contact zone behaviour 3- Meshing problems, topography effects, border meshes of concrete dams have geometric problems, no automatic method to create hexahedral high quality mesh. 4- Non reflective boundaries, software to use PML Validation 5- Inertia effects of the foundation 6- Non-linear dam analysis Concrete Joint Especially for MCE (Maximum credible earthquake) 7- Stress criteria for dam design and evaluation of existing 1D 2D 3D / Concrete testing methods 2

8 Numerical hot issues identified by the participants Committee A meeting Seattle, August, 2013 Embankment dams 1- Modelling unsaturated flow And impacts on stability and deformation 2- Modelling interface problems of different materials (soil, concrete) and spatial effects. 3- Input parameters for constitutive methods and correct data for analysis 4- Modelling of piping mechanisms and how to analyse 5- Long term behaviour of rockfill Loss of free board Size effects 6- Performance under overtopping 7- Asphalt core behaviour (Norway vs Russia) 8- Impact of cold on the clay cores (potential fracture) 3

9 Two latest bulletins of the committee A 4

10 Why a new bulletin? Committee A has complied the Bulletin 155 Guidelines for Numerical Models in Dam Engineering. The bulletin deals with important issues of the numerical models in dam engineering. Since, the bulletin 155 was intended to be used as guidelines, details have been avoided and all issues have only generically been addressed. The intension of the proposed bulletin is to address some important details of numerical modelling, those related to Non-linear Modelling of Concrete Dams (NLMCD). 5

11 The new bulletin The bulletin provides guidance for the application of nonlinear analysis techniques for the design and evaluation of concrete hydraulic structures. It introduces procedures that show how to take into account the non-linear behaviour of constituent materials, joints, cracks, supporting structures and foundations etc. The bulletin presents procedures for Non-linear Static, and Non-linear Dynamic analyses. In particular, procedures for the analysis of transient processes such as seismic response, settlements, temperature effects etc. The bulletin disregards, however, geometric nonlinearity. 6

12 Participating members 7

13 Content 8

14 Thank you for your attention! 9

15 Bilaga 1 A p. 1 A) COMPUTATIONAL ASPECTS OF ANALYSIS AND DESIGN OF DAMS A) METHODES DE CALCULS POUR BARRAGES PROGRESS REPORT RAPPORT D ACTIVITÉ Meeting in Stavanger, 13 rd June 2015 Réunion à Stavanger, 13 juin 2015 MEMBERSHIP / LISTE DES MEMBRES MEETING / Réunion COUNTRIES PAYS MEMBERS MEMBRES Present Absent/Substitutes Spain ESCUDER Ignacio Chairman YES Italy MAZZA' G. Vice-C. YES Italy MEGHELLA M. Member YES Italy FANELLI M. Hon.Member NO France CARRERE A. Hon.Member NO Argentina RESTELLI F. Member NO Australia LOPEZ F. Member NO Malcolm Barker Austria ZENZ G. Member YES Canada CURTIS D. Member NO China CHEN S. Member YES Colombia MARULANDA C. Member YES Finland VARPASUO P. Member YES Form.Yug. Yugoslavia TANCEV L. Member NO France FROSSARD E. Member YES Germany BEETZ U. Member NO Greece DAKOULAS P. Member NO Iran GHAEMIAN M. Member NO Japan NOGUCHI Y. Member YES Norway ANDERSEN R. Member YES Romania POPOVICI A. Member NO Daniel Gaftoi Russia GLAGOVSKY V. Member YES Slovakia MINARIK M. Member NO Sweden HASSANZADEH M. Member YES GUNN R.M. Member NO Turkey OZEN O. Member NO Altug Akman United States MATHEU E. Member NO OBSERVERS: Salih Bilgin AKMAN, Miroslav Broucek, Kyrylo RYZHYKOV, Eehab Ahmed Badr-El-din Khalil

16 Bilaga 1 Committee A hold a Workshop on June 12, 2015, at Stavanger Forum from 10:00am to 10:45am, with more than 40 total attendees. It included a series of presentations linked to coming celebration of the XIII ICOLD Numerical Benchmark Workshop, to be hold in Lausanne,, September , following a tradition that lasts for more than 20 years (started in Bergamo, 1991). Namely: Overview of Committee A and Benchmark Workshops (BW) on Numerical Modelling of Dams by Guido Mazzà: Presentation of Theme A on Seismic safety evaluation of a concrete dam based on guidelines by Massimo Meghella Presentation of Theme B on Probability of failure of an embankment dam due to slope instability and overtopping by Ignacio Escuder Presentation of Theme C on Safety evaluation of dams by Guido Mazzà. Open discussion on capitalization of results and future initiatives On June 33, from 9am to 13pm the Committee A meeting included the following agenda items: A - p. 2 Welcome and review of last meeting (Bali 2014) minutes, recalling the fact that next year, in 2016, the Committee will have to propose another Benchmark Workshop, select a host, revisit the terms of reference and prepare an extension application. An in-depth presentation of the status of the coming Benchmark Workshop was given by Massimo Meghella, Guido Mazzà and Ignacio Escuder. It included expected participants (so far around 40 participants among the three Themes), organizational issues and practical and scientific challenges of the Themes. The presentation was followed by a very rich debate reflecting the interest and importance of the topics. On-going tasks. ü ü The discussion on numerical and computational needs with regard to risk analysis and assessment highlighted the fact that Lausanne is going to be the third Benchmark Workshop in which a risk analysis theme is addressed, and it closes a loop after dealing with failure risk of concrete dams (Valencia 2011), consequences (Graz 2013) and now failure risk of embankment dams (Lausanne 2015). It was decided to writhe a synthesis paper on the lessons learnt from the three events. Manouchehr.Hassanzadeh, in close cooperation with Massimo Meghella, presented significant advances on the guidelines on numerical non-linear analysis with emphasis on discontinuities of concrete dams, including a complete index and several contents. The group had a very fruitful discussion and several members of the committee committed to give further collaboration in order to have a first drafted document for next year. Following the open discussion on how to proceed to capitalize the results of XII BW held in Bali, task since then undertaken by Önder Özen, it was agreed to finish the task within next year, so that it can be presented either at the South Africa Annual Meeting (June 2016) or the Antalya European Club of ICOLD Symposium (October 2016)

17 ICOLD BULLETIN N XXX NON-LINEAR MODELLING OF CONCRETE DAMS NLMCD M. Hassanzadeh & M Meghella

18 Numerical hot issues identified by the participants Committee A meeting Seattle, August, 2013 Concrete dams 1- Dynamic behaviour of abutments Crude methods for stability 2009 workshop Russell Gunn 2- Foundation contact zone behaviour 3- Meshing problems, topography effects, border meshes of concrete dams have geometric problems, no automatic method to create hexahedral high quality mesh. 4- Non reflective boundaries, software to use PML Validation 5- Inertia effects of the foundation 6- Non-linear dam analysis Concrete Joint Especially for MCE (Maximum credible earthquake) 7- Stress criteria for dam design and evaluation of existing 1D 2D 3D / Concrete testing methods 2

19 Numerical hot issues identified by the participants Committee A meeting Seattle, August, 2013 Embankment dams 1- Modelling unsaturated flow And impacts on stability and deformation 2- Modelling interface problems of different materials (soil, concrete) and spatial effects. 3- Input parameters for constitutive methods and correct data for analysis 4- Modelling of piping mechanisms and how to analyse 5- Long term behaviour of rockfill Loss of free board Size effects 6- Performance under overtopping 7- Asphalt core behaviour (Norway vs Russia) 8- Impact of cold on the clay cores (potential fracture) 3

20 Two latest bulletins of the committee A 4

21 Why a new bulletin? Committee A has complied the Bulletin 155 Guidelines for Numerical Models in Dam Engineering. The bulletin deals with important issues of the numerical models in dam engineering. Since, the bulletin 155 was intended to be used as guidelines, details have been avoided and all issues have only generically been addressed. The intension of the proposed bulletin is to address some important details of numerical modelling, those related to Non-linear Modelling of Concrete Dams (NLMCD). 5

22 The new bulletin The bulletin provides guidance for the application of nonlinear analysis techniques for the design and evaluation of concrete hydraulic structures. It introduces procedures that show how to take into account the non-linear behaviour of constituent materials, joints, cracks, supporting structures and foundations etc. The bulletin presents procedures for Non-linear Static, and Non-linear Dynamic analyses. In particular, procedures for the analysis of transient processes such as seismic response, settlements, temperature effects etc. The bulletin disregards, however, geometric nonlinearity. 6

23 Participating members 7

24 Content 8

25 Thank you for your attention! 9