As barragens de enrocamento com face de concreto (BEFC) têm sido construídas com freqüência crescente em todo mundo. Apesar disso, os critérios de. Many translated example sentences containing “barragens de enrocamento” Simpósio Sobre Barragens de Enrocamento com face de Concreto [ ]. 15 out. PERCOLAÇÃO NAS BARRAGENS DE ENROCAMENTO COM FACE DE CONCRETO EM CONSTRUÇÃO – Nelson L. de S. Pinto.
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The success of these dams, with heights of up to m Chicoasen Dam, in Mexicorestarted the construction of concrete face rockfill dams, attractive for their lower cost and shorter time of construction when local rain fall conditions are restrictive for soil compaction.
Flávio Alberto Crispel
The concern then changed from the perimetral joint to the tensile joints seals in abutment slabs. This study aims at presenting a discussion on the main factors of development of these stresses.
This model must be dynamic, not only to define the zoning of the embankment as well as future adjustments, in function of the monitoring during the construction.
All failures occurred in the central slabs caused from high compressive stresses, presenting an unknown behavior in such type of dam. He received many awards for his brilliant professional performance, such as the Distinguished Engineering Alumnus Award, from the University of Berkeley — California, and the Terzaghi Barragesn offrom the American Society of Civil Engineers. Help Center Find new research papers in: Cracks may occur in the concrete face; they would be tolerable since the embankment resists to the flow and the cracks can be easily sealed by placing fine material sandy silt.
These modifications barragens successfully introduced in dams built in Brazil and in the world; however, all of them with height below m the height of Foz do Areia dam.
This model barragns consider the joints between the slabs of bareagens concrete face. Remember me on this computer. Barry Cooke is invaluable. In other cases, leakages occurred by the failure of water stops due to excessive deformation. Such major infiltrations were associated to excessive displacements of the slabs in relation to the support plinth, whose perimetral joint was not designed to bear such displacement.
The basic principle stated by Cooke – Ref. Compressive stresses in the concrete face with 4 Joints MPa These results show that compressible joints are effective to avoid the development of high compressive stresses.
Flávio Alberto Crispel
This dam, built in open valley, has been showing excellent performance, and enrocammento a reference. Wetting of all the materials and in every zone should be done, not only in the upstream third, as usual. For a more favorable behavior in relation to these efforts, the concrete face should be divided into panels that can ebrocamento or eliminate some of the soliciting efforts above mentioned. In his works, Cooke states that the principle of precedents must be followed, but it cannot be restrictive to the progress, either for the implementation of higher dams or for the adoption of more cost-effective solutions.
Compressive stresses in the baeragens face without joint MPa Figure 2 shows a map of the compressive stresses in the concrete face considering compressible joints in the region of the face A notable reduction in the the compressive stresses could be observed.
Continuous compaction control, through equipments installed in the roller, could be an interesting measure to improve the control of the fill. Except for the Salvajina dam, the others were built in narrow valleys.
It must be pointed out that this feature is critical on abutments. Due to the result of the computations, double reinforcement mesh was adopted in large portion of the concrete face, contrary to the usual practice of using a single mesh in the center of the face.
Also the thickness of the compaction layers should be adjusted, in function of the quality, gradation and shape of materials and of the type of compacting roller used. However, the larger compression stresses may not be only “horizontal” along the whole concrete face.
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It also presents reflections for criteria development for future design of very high CFRDs in order to avoid such failures. From toafter the good behavior observed in six dumped rockfill dams belonging to Pacific Gas and Electric Company USAwith heights between 23 and 45 m, higher dams were built, among them are the Salt Springs Dam USA and Paradela Dam Portugalwith heights of and m, respectively.
On the other hand, the tensile joints seals of the slabs on the abutments regions should be capable to absorb the largest displacements resulting from the compression of the joints in the central area.
In the decade of the df Foz do Areia Dam, in Brazil, was built with m of height, at that time the largest in the world. However, an ordered design approach is fundamental to guarantee an adequate performance of future high CFRD dams. However, some of these dams presented infiltration problems.
REFLECTIONS ON NEW DESIGN OF VERY HIGH Concrete face rockfill dams | Ciro Humes –
Compressive joints should be used in a way to allow the movement of the central slabs and relieve the compressive stresses among them. Enter the email address you signed up with and we’ll email you a reset link. Thus, progressive modifications were introduced in the CFRD design, among them: The results should receive continuous analysis to allow the necessary actions in the design and in the constructive methods.
His contribution in the development of this type of dam is invaluable, having participated of all Consultants Committees of CFRDs built in Brazil see Table 1 and practically of the construction of the main dams of this type around the world. Log In Sign Up. Click here to sign up.
This prediction must take in place the geological-geotechnical features, the shape and topography of the valley and the properties of available construction materials. At Campos Novos Dam, built in a narrow valley, the displacements of the superficial benchmarks showed an accentuated move towards the center of the valley. This problem was solved in further dams by changing the zoning of the fill material in the region of interest and new design of the perimetral joint, which had more than one sealing element and, as an additional defense line, when viable, a clay fill on the perimetral joint.
Barry Cooke died in