Safe Dams

Background

Current stability assessment methods for dams are often analytical and require large simplifications to obtain results. Furthermore, the mechanical properties of concrete and rock may vary greatly over the volume of the dam and its foundation. These variations become uncertainties, thereby affecting the confidence of a structure's safety, and are not fully accounted for in the current stability assessment methods for dams. However, by combining numerical analysis, giving approximate solutions to complex problems obtained through computer programs or algorithms, and reliability analysis, which accounts for uncertainties of influential variables, the shortcomings of the current stability assessment methods may be remediated. Furthermore, by performing experimental tests on physical scale models enables validation of the numerical analysis model. Through a combination of these methods, a more robust dam safety assessment approach, than current ones, may be obtained.

Aim and objectives

The aim of this project is to evaluate and promote a multidisciplinary approach to assess the capacity of existing and new concrete dam structures.

The objective is to develop a better method for assessing the concrete dams' safety and load capacities by combining reliability-based and probabilistic assessments with finite element modelling, and scaled down model tests.

Facts

Finances: FORMAS (Grant No. 2019-01236) and SVC (Grant VKU32019).

Timeline: Project start in Dec 2020 and Project end (planned) in Nov 2025.

Principal Investigator: Gabriel Sas.

Team members: Adrian Ulfberg, Jaime Gonzalez-Libreros, Chao Wang.

External collaboration: Fredrik Johansson (KTH), Marie Westberg-Wilde (KTH & Afry), Richard Malm (FOI)

Dissemination

1) Enzell J, Ulfberg A, Sas G, Malm R.Post-peak behavior of concrete dams based on nonlinear finite element analyses. Engineering Failure Analysis External link. External link.. 2021;130:105778.

2) Probabilistic finite element analysis of failures in concrete dams with large asperities in the rock–concrete interface (2023). Ulfberg. A, Gonzalez-Libreros. Yes, Das. Oh, Bista. D, Westberg Wilde. M, Johansson. F et al.

3) Ulfberg A, Gonzalez-Libreros J, Das O, Sas G, Andersson E, Bista D, et al.Influence of large-scale asperities on the stability of concrete dams External link. External link.. IABSE Symposium: Challenges for Existing and Oncoming Structures; Prague2022. pp. 1358-65

4) Ulfberg A, Seger A, Bista D, Westberg Wilde M, Johansson F, Das O, et al.Influence of concrete's mechanical properties on the cracking of concrete dams External link. External link.. In: Castanier B, Cepin M, Bigaud D, Berenguer C, editors. ESREL2021: 31st European Safety and Reliability Conference; Angers, France2021. pp. 1326-33.

5) On the applicability of scale model tests for concrete dams: A Review (2023)
Ulfberg. A, Gonzalez. Yes, Das. Oh, Sass. G, Ore. R, Johansson. F et al.