China
Africa
Explore chapters and articles related to this topic
Planning, Project Cost Estimation, and the Future of Small Hydropower (SHP): Large Hydro and Its Various Schemes and Components
Published in Suchintya Kumar Sur, A Practical Guide to Construction of Hydropower Facilities, 2019
Buttress dam: A buttress dam is a hydraulic structure having an RCC flat slab in the upstream side that is supported by a series of buttresses in the downstream to transfer the load. Buttresses are compressive members. They may be either curved or straight in plan and made of reinforced concrete. It is also called hollow dam.
Reservoirs and Dams
Published in F.G.H. Blyth, M. H. de Freitas, A Geology for Engineers, 2017
F.G.H. Blyth, M. H. de Freitas
A buttress dam consists of a series of inclined watertight slabs as its upstream face, supported by a series of buttresses which are triangular in vertical section (Fig. 15.10b and c). It is less massive than a gravity dam and uses smaller quantities of construction material. The strength of the concrete is used to better effect than in a gravity dam (where concrete weight is the prime factor), as the pressure of water on the upstream face is exploited to load the buttresses and assist the stability of the structure. Foundation loads are high, but may be reduced by widening the base of the buttress (see Fig. 15.14).
Concrete dam engineering
Published in P. Novak, A.I.B. Moffat, C. Nalluri, R. Narayanan, Hydraulic Structures, 2017
P. Novak, A.I.B. Moffat, C. Nalluri, R. Narayanan
Buttress dams fall into two distinct groups, as identified in Section 1.4. Massive diamond or round-headed buttress dams representative of modern practice were illustrated schematically in Figs1.4(b) and 1.4(c). The earlier but now largely obsolete flat slab or Ambursen buttress dam was also shown, in Fig. 1.5(c). The latter type is not considered further. Relative to the gravity dam the principal advantages of the massive buttress dam lie in its obvious economy of material and in a major reduction in uplift load. The buttress dam also offers greater ability to accommodate foundation deformation without damage. The advantages listed are offset by considerably higher finished unit costs (overall cost of the completed dam per m3 of concrete) for the reduced quantities of concrete employed. This is attributable largely to the cost of the more extensive and frequently ‘non-repetitive’ formwork required. Significantly increased stresses are also transmitted into the foundation of each buttress. The criteria for foundation competence are therefore appreciably more rigorous than those applicable to the gravity dam.
Industrial Heritage Assessment and Guidelines for the Architectural Conservation of Hydroelectric Plants
Published in International Journal of Architectural Heritage, 2021
The most crucial and distinctive element of a hydroelectric plant is the dam. Dams are constructed using various methods and materials, depending on the hydrologic properties, topography, geology, climate and seismicity of the surrounding, the availability of the materials and economic conditions. The three main categories are fill dams, masonry dams and concrete dams. Fill dams (earth-fill and rock-fill dams) are embankments constructed of compacted natural materials (earth or rock), and they rely mainly on their weight to counterbalance the thrust of water. Because of their wide-based triangular geometry, they are usually preferred in landscapes where the ground conditions are weak or heterogeneous and where the water level is low. There are cases where the upstream face of the embankment is covered with concrete slabs in order to provide impermeability. Masonry dams are structures built out of cut-stone or brick. Concrete dams are generally constructed of unreinforced blocks of concrete with flexible seals at the joints. Different types of masonry dams and concrete dams, according to their construction techniques, are gravity dams, buttress dams and arch dams. Gravity dams are structures which depend on their weights in order to resist the power of water acting on them. Therefore, they require strong ground conditions and well-designed foundations. Buttress dams also work with the same principle, except for the fact that in a buttress dam, the concrete slab is thinner and it is supported by a series of buttresses on the downstream side. Arch dams are curved structures with the top of the arch facing upstream so that the pressure of water compresses the structure which transfers the load to the sides of the valley through its abutments and to its foundation. Arch dams are constructed at narrow valleys where the sides of the canyon are stable and stiff. In many cases, arch dams are double-curvature structures, curved on horizontal and vertical planes similar to a section of a sphere (Figure 5). There are also cases — such as arch-gravity dams — where a combination of techniques is implemented.