- Other concrete dams.A number of less common variants of the major
types of concrete dams illustrated in Fig. 1.4 can also be identified.
They include hollow gravity, decked buttress, flat slab (Ambursen)
buttress, multiple arch, and multiple cupola dams, as illustrated in
Fig. 1.5. The type names are self-explanatory, and the structural
parentage of each as a derivative of one or other of the principal types
is apparent from the figures. In view of this and the relative rarity of
these variants they are not considered further in this text, but the com-
parative vulnerability of the slender flat slab and similar types to
seismic disturbance etc. may be noted.
The characteristics of concrete dams are outlined below with respect
to the major types, i.e. gravity, massive buttress and arch or cupola dams.
Certain characteristics are shared by all or most of these types; many are,
however, specific to particular variants. Merits shared by most concrete
dams include the following.
- Arch and cupola dams excepted, concrete dams are suitable to the
site topography of wide or narrow valleys alike, provided that a com-
petent rock foundation is accessible at moderate depth (5m).
- Concrete dams are not sensitive to overtopping under extreme flood
conditions (cf. the embankment dam).
18 ELEMENTS OF DAM ENGINEERING
Fig. 1.5 Further variants of concrete dams