Title: Failure Mechanisms and Rehabilitation Scenarios for Concrete Hydroelectric Facilities Affected by Alkali–Aggregate Reaction

Author(s): Mahdi Ben Ftima and Emre Yildiz

Publication: IJCSM

Volume: 17

Issue:

Appears on pages(s):

Keywords: Alkali–aggregate reaction, Concrete hydroelectric facilities, Failure mechanism, Retrofitting strategies, Multi-physical simulation, Nonlinear finite element analysis

DOI: 10.1186/s40069-023-00590-8

Date: 9/30/2023

Abstract:
This work focuses on the failure mechanisms of concrete hydroelectric facilities affected by alkali–aggregate reaction (AAR). Identification of potential failure mechanisms is based on an original “top-down approach” using an AAR pushover analysis with multi-physics numerical simulation of a representative hydroelectric facility. Different global rehabilitation scenarios based on slot-cutting and grouting techniques are discussed and compared, using different performance metrics. A new quantitative performance metric, specifically developed for the nonlinear sophisticated analysis tool and considering the volumetric cracking caused by AAR is also suggested. Based on comparison results, a combination of grouting after a partial slot-cutting in the neighborhood of the discontinuities, appears to provide the best compromise in terms of stress relief and extent of cracking. New AAR benchmark problems, issued from the top-down approach, are also suggested for the first time in the literature.