Simulation of Cracking in Large Arch Dam: Part I

Abstract

A complete fracture mechanics investigation of the cracking of the Kolnbrein arch dam is presented in two parts. In Part I, the history of cracking of this dam and theories attempting to explain it are described. The fundamental principles of mixed‐mode, linear elastic fracture mechanics are then elucidated and used to study cracking observed near the toe of the dam. The stability, trajectory, and opening of two cracks are computed and favorably compared to observations. In Part II, cracking which occurred in the heel region of the dam is investigated next using computer simulation and fracture mechanics in an attempt to reproduce observed trajectory and load history before cracking. Four models for the cause of this cracking are described. All four models are shown to be viable mechanisms within the constraints of available cracking data. The necessity for combining simulation with accurate data of various types, and the insufficiency of two‐dimensional analysis are discussed. The significant implication of this study is that classical fracture mechanics theory, implemented through modern computer simulation techniques, can be used to explain cracking events in concrete arch dams. This capability can prove valuable in designing against such events, and in specifying effective repair procedures.