M.K. JAFARI - Assoc. Professor, Director of Geotechnical Eng., Research Center of IIEES, Tehran, I.R. Iran
M. DAVOODI - Ph.D. Student of IIEES, Tehran, I.R. Iran,

A complete ambient vibration test of the Masjed-Soleiman (MS) embankment dam due to lowlevel loads such as wind, machinery activities, low level tectonic activities, spilling of the reservoir and water exit from bottom outlet was performed. These kinds of ambient vibration tests are suitable for manifesting smaller modes of vibration of the dam body.Furthermore, the response of the dam body to large explosive charges in quarries and underground power plant house were measured. Since, the energy resulted from the blastgenerated ground motion contains the high frequency waves, this kind of test is appropriate for exciting high vibration modes of the dam. The results of these tests have been used to evaluate the natural frequencies, mode shapes and modal damping of the dam body. In order to investigate the effects of water level variation on modal parameters of the dam body, the ambient vibration tests have been done during impounding and spilling the reservoir. Finally the 3-D modal analysis of the dam body was performed using ANSYS software. Dynamic soil properties of the dam body and foundation materials were calculated based on results of the cyclic triaxial and resonant column tests, consulting engineering reports and appropriate geoseismic refraction investigations. Foundation interaction effects were also investigated by modeling different foundation depth and inertial properties. In this paper, the numerical analysis results and also its comparison with the dynamic characteristics of the dam body obtained from the full-scale dynamic tests will be presented and discussed

Embankment Dam, Ambient Vibration Test, Explosion, Modal Properties