Title:
Fracture Mechanics Application to Evaluate the Failure
Mode and Ultimate Strength of Tailgate Walls in a Hydropower plant.
Author(s):
Sudip S. Bhattacharjee and Vladimir Gocevski
Publication:
Structural Journal
Volume:
94
Issue:
6
Appears on pages(s):
686-694
Keywords:
concrete dams; finite element; fracture mechanics; safety
assessment; size-effect.
DOI:
10.14359/9728
Date:
11/1/1997
Abstract:
Failure modes and ultimate strengths of existing solid concrete gate walls in hydropower plants are not well understood in the present engineering practice. A continuum fracture simulation model, corroborated with exper-imental model studies, is considered in this paper for the safety assessment of tailgate walls of Beauharnois Power station in Quebec. Numerical simu-lation of the structural fracture response needs a priori experimental investigations to determine the material fracture parameters. However; fracture properties of concrete in existing structures are often not known, and experimental procedures for the determination of in situ fracture properties are also not well developed. In this paper, fracture properties of concrete are determined from the measured compress strengths by using the empirical relationships proposed in the literature. A smeared fracture analysis model, specifically developed for the fracture simulation studies of mass concrete structures, is applied to corroborate the reduced scale model test results. The validated tool is subsequently applied to assess the ultimate strength of an idealized finite element model of a tailgate wall. Effects of retrofitting measures that may be applied in similar structures to enhance the fracture resistance are also investigated in this paper.