Dynamic Testing and Acoustic Analysis of Concrete Dams

Forced vibration tests of Pacoima Dam were performed as part of a continuing research effort for dam integrity monitoring. The results of these tests are presented including measured resonant frequencies and response shapes, estimated modal damping ratios, and measured acoustic emission properties.

The goal of this research is to develop a field portable test method for damage and integrity assessment of concrete dams. In this method, the dynamic properties and the acoustic emission properties of dams are monitored to detect and locate arch and foundation defects.

Comparison of the dynamic properties obtained in the present tests to dynamic properties obtained in tests performed shortly after the 1971 San Fernando earthquake tentatively confirm that gross structural changes can be detected.