Wednesday, July 12th, 2023. Time: 12 noon

Hybrid / O.C. Zienkiewicz Conference Room, C1 Building, UPC Campus Nord, Barcelona

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ABSTRACT

With the increasing knowledge in seismicity, a growing number of dams fail to meet revised safety criteria that incorporate this new seismic hazard information. Therefore, the validity of the original design requirements needs to be revised. Probabilistic methods allow a wide variety of configurations to be considered, constituting the basis of more adequate design and assessment procedures.

Metamodels drastically reduce the need for simulation runs, thereby decreasing the time and effort needed to simulate the structural response when analyzing a wide variety of dam-system scenarios. In this seminar I will present (recently published and unpublished work) the seismic fragility-based safety assessment of a gravity dam, performed using a dual-layer metamodel. The first layer emulates and replaces the continuous output of the software and allows the safety factor to be predicted, while the second layer provides the probability of not reaching this safety factor by generating parameterized multivariate fragility functions. To explicitly account for the effects of parameter uncertainties, multidimensional integration is implemented to update the fragility functions. Accordingly, recommendations can be formulated concerning the conditioning parameter’s minimum values to achieve the expected performance when additional information regarding the remaining parameters is acquired. Although the availability of additional information may not have a substantial impact on reducing the uncertainty in the fragility estimates, the proposed methodology allows for the identification of such cases and considers the anticipated value of further efforts to reduce uncertainty as a factor in selecting a course of action.

SPEAKER CV

Rocio L. Segura is an assistant professor in the Department of Civil, Environmental and Sustainable Engineering at Santa Clara University (SCU) since September, 2022. Prior to that, she obtained the Mitacs Industrial Postdoc Fellowship, to do her postdoc with Hydro-Quebec as an industrial partner in the project entitled: Accounting for uncertainties in dam safety assessment via machine learning techniques [1,2,3]. The main goal of this project was to adapt procedures developed in an academic framework to the practical needs of the industry so that resources can be redirected in the exhaustive study of those parameters introducing the most uncertainty into the analysis and affecting dam behavior.

She received her bachelor’s in civil engineering from Del Comahue National University in Argentina. After graduation, she worked as a structural engineer in a dam consulting company, and in 2015, she started her Ph.D. at Sherbrooke University, Quebec, Canada. Her Ph.D. research focused on the generation of metamodel-based fragility functions to estimate the performance of gravity dams under seismic loading. During her post-graduate training, she travelled to other institutions as a visiting researcher (IUSS in Pavia, Italy, Rice University in Houston, USA and University of Canterbury in Christchurch, New Zealand) and collaborated in the production of journal articles with well-known researchers and their respective research groups [4,5,6]. This has given her not only access to new information and new and balanced interactions with her peers, difficult to achieve otherwise, but also it has provided her a well-rounded experience working with people from all backgrounds.

Ms. Segura is a registered professional in Argentina and Quebec and has several years of professional experience as a structural engineer in the public and private sectors. Ms. Segura has a strong interest in dam safety, structural and earthquake engineering, risk assessment, applied probability, and machine learning applied to civil engineering.

[1] Segura R, Frechette V, Miquel B, Paultre P (2022). Dual layer metamodel-based safety assessment for rock wedge stability of a free-crested weir. Engineering Structures; (268)114691.

[2] Segura R, Miquel B, Paultre P, Padgett J (2021). Accounting for uncertainties in the safety assessment of concrete gravity dams: A probabilistic approach with sample optimization. Water; 13.

[3] Segura R, Padgett J, Paultre P (2021). Expected seismic performance of gravity dams using machine learning techniques. Bull N Z Soc Earthq Eng; 54:58–68.

[4] Segura R, Padgett J, Paultre P (2020). Metamodel-based seismic fragility analysis of concrete gravity dams. J Struct Eng; 46:04020121.

[5] Segura R, Bernier C, Durand C, Paultre P (2019). Modelling and characterizing a concrete gravity dam for fragility analysis. Infrastructures; 4:1–19.

[6] Segura R, Bernier C, Monteiro R, Paultre P (2019). On the seismic fragility assessment of concrete gravity dams in Eastern Canada. Earthquake Spectra; 35:(1)211–231.

Seminar Programme 2023