Hydromechanical Evaluation of Flow Behavior in Rock Foundations of Concrete Gravity Dams

The main concluding points of the study can be summarized as follows: (1) Present design uses a constant cohesion intercept along potential sliding surfaces, regardless of the magnitude of the effective normal stresses, to explain satisfactory structural behavior observed in concrete dams. The results obtained in this study indicate that adequate dam behavior might actually be the result of factors other than cohesion, such as the presence of 3-D rock wedges at the dam foundations, the arching of reservoir water loads into the abutments, the hydromechanical interaction along foundation joints and enhanced natural drainage. (2) For the dams analyzed in this study, estimated changes in rock joint permeability within dam foundations during reservoir filling are in the range of one to two orders of magnitude along the dam rock interface instead of the extreme permeability contrast assumed in current design guidelines (FERC, USBR), which assume open crack at full reservoir and closed at the tip of the crack. (3) The hydromechanical analyses carried out in this research indicate a gradual reduction in factors of safety during reservoir filling assuming that drains work beyond maximum operating elevations, instead of the rapid reduction obtained with design guidelines.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Civil Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Gimenes, Evandro De Avila

Contributors dc:contributor

• Gabriel Fernandez

• Geology

Language dc:language

eng

Identifier

(MiAaPQ)AAI9990005

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/83519