SMALL DAMS PETITS BARRAGES

It is common knowledge that RCC is a construction technique, and not a design concept.
However, when discussing projects that may use the RCC technique, two basic points are
usually taken into account:
Treatment and characteristics of construction joints between lifts; and
Watertightness and durability, of the upstream face type, seepage and drainage
factors and control.
On the following table are presented the main dimension of two small RCC Brazilian
dams, in which the cementitious content of the concrete was only 80 Kg/m³.
Table 2.1 – Example of two small RCC Brazilian dams
Name
Height
(m)
Length
(m)
Volume
( m³)
Cementitious
Content (Kg/m³)
Mocoto 12 117 8,000 80
Trairas 11.7 116.5 4,300 80
Fig. 2.12 – Trairas RCC concrete dam – Brazil
The 14m high Neusberg RCC concrete gravity weir in the Orange River, Republic of
South Africa, was shaped to accommodate high uplift pressures of large floods for long
durations at intermediate tail water levels between full submergence level and river bed level
(Fig. 2.13). The stability requirements gave reason for shaping the crest nape profile for
accommodating the probable maximum flood. This provided a wide cross section which suited
placement of concrete by larger vehicles and compaction by large vibratory compactors.
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