ABSTRACT
The major difference is that for dams they extend into three dimensions. The mode shape is, in practice, supplemented by a displacement that is a function of the height up the dam. The vertical mode shape is similar to the modes shown in Fig. 4.3 for tall buildings or for chimneys. The resulting modes of vibration are a combination of the spanwise modes (similar to bridges) and the vertical modes (similar to tall buildings). Each mode of vibration is a combination of such modal pairs. Mode shapes of dams are a strong function of the individual structure, and so measurements in detail are presented from tests on full-scale dams in Chapter 6.
