THERMAL-DAMAGE OF MASS CONCRETE - EXPERIMENTAL AND NUMERICAL-STUDIES ON THE EFFECT OF EXTERNAL TEMPERATURE-VARIATIONS

According to a report published by the International Commission on Lar ge Dams in 1984, approximately 34% of all dams are damaged by thermal problems. In this paper, the effects of external temperature variation s on mass concrete have been investigated through laboratory experimen ts. A concrete block, instrumented with thermocouples and vibrating wi re extensometers and exposed to temperature variations on one face, wa s used to simulate the behavior of the downstream face of a concrete g ravity dam exposed to thermal cycles. A numerical procedure simulating the thermal effect was performed and compared with the experimental r esults. Once the validity of the numerical procedure was established, it was used to investigate the effects of the variation of outside tem peratures on the thermal and mechanical behavior of a typical gravity dam situated in northern Quebec.