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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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.
These suggestions should be analyzed for each case.
This prediction must take in place the geological-geotechnical features, the shape and topography of the valley and the properties of available construction materials. 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. 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.
Flávio Alberto Crispel
This would be an acceptable approach for CFRDs have intrinsic stability in function of the following features: The results should receive continuous analysis to allow the necessary actions in the design and in the constructive methods. However, it seems that his confidence in the stability of this type of dam regarding its resistance to normal operation loads and fac the action of eventual water seepage led to adoption of some practical design criteria not totally applicable in very high dams built in narrow valleys, where stress levels extrapolated the already experienced values.
Skip to main content. The instrumentation of the embankment and of the concrete face should be intensified to reflect dam performance, mainly of its singularities. This problem was solved in further dams by changing the zoning of ennrocamento 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.
For a more favorable behavior in relation to these efforts, the concrete face should be divided into panels that can reduce or eliminate some of the soliciting efforts above mentioned. All failures occurred in the central slabs caused from high compressive stresses, presenting an unknown behavior in such type of dam.
II SIMPÓSIO SOBRE BARRAGENS DE ENROCAMENTO
Such width reduction would also restrict the area of the slabs where torsional moments may occur. Barrragens other cases, leakages occurred by the failure of water stops due to excessive deformation. Enter the email address you signed up with and we’ll email you a reset link. Cracks may occur in the concrete face; they barragrns be tolerable since the embankment resists to the flow and the cracks can be easily sealed by placing fine material sandy silt.
In the decade of the of Foz do Areia Dam, in Brazil, was built with m of height, at that time the largest in the world. Thus, progressive modifications were introduced in the CFRD design, among them: He received enrkcamento awards for his brilliant professional performance, such as the Distinguished Engineering Alumnus Award, from the University of Berkeley — California, and the Terzaghi Lecturer offrom the American Society of Civil Engineers.
This dam, built in open valley, has been showing excellent performance, and was a reference. Click here to sign up. However, some of these dams presented barragns problems.
Compressive stresses in the concrete 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. Wetting of all the materials and in every zone foncreto be done, not only in the upstream third, as usual.
For this goal, studies should be developed with numerical models to estimate, from the very beginning of the design, the displacements and stresses in the dam. The basic principle stated by Cooke – Ref. Such failures motivated the abandonment of this type of solution for dams until when, with the development of heavy vibrating rollers for compaction of rockfill in barrages, high rockfill dams with clay core started to be built.
Flávio Alberto Crispel
Except for the Salvajina dam, the others were built in narrow valleys. Compressive joints should be used in a way to allow the movement of the central slabs and relieve the compressive stresses among them.
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 fcae for the adoption of more cost-effective solutions. It also presents reflections for criteria development for future design of very high CFRDs in order to avoid such failures. It is worth repeating the technical contribution of Mr.
It must be pointed out that this feature is critical on abutments. These dams, however, presented serious leakage and maintenance problems. These modifications were 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.