Comparison of shear wave velocities evaluated in the core zone of an existing fill dam by field and laboratory tests

Abstract

The objective of this study is to compare shear wave velocities evaluated by laboratory and field tests in the core zone of an existing fill dam, and to verify the applicability of empirical methods by comparing the shear wave velocities evaluated by empirical methods with those evaluated by experimental methods. In this study, boring and sampling were conducted at the Yeongcheon dam in Korea. Laboratory tests on the core samples were carried out and field tests such as borehole surveys and seismic methods were conducted to evaluate the shear wave velocity. The results obtained by laboratory and field tests were compared. Furthermore, the results obtained by these experimental methods were compared with those obtained by empirical methods. The shear wave velocity determined by the seismic methods was, to a limited extent, lower than that determined by the borehole surveys at shallow depths of less than 15m, but was predicted to be similar at depths deeper than 15m. The results of the two kinds of laboratory tests were almost similar to each other but both the results were 10–20% lower than those obtained by the seismic methods. The results obtained by the empirical method based on the field tests and the measured in-situ records were similar to the field test results. On the other hand, the results obtained by the empirical method using the basic properties of sample cores were similar to the laboratory test results.