Published in Journal of Young Scientist, Vol.I
Written by Robert Cristian SOFRONIE, Constantin ENACHE
The gravity dams are massive constructions, built out of concrete, which counteract the force of water pressure with only action of self-mass. First dam of this type was built around 1220 in Spain, and the building method remained the same until today, the only difference being the building technique and the materials used. The reasons for which the gravity dams need rehabilitation are mainly the time damage and the destructive effects of flash floods and earthquakes effects. Nevertheless, their lifetime can be extended if regular maintenance applied, which most frequently, in the case of cracks presence, it means: waterproofing the fissured areas with epoxy resins, injecting the fissured areas or reinforcing the dam with tension cables in those areas which present horizontal cracks. In the case of Clucereasa’s dam, the deterioration was caused by the extraordinary solicitations of the large quantities of water in transit during the flash floods. This thing leaded to the dilapidation of the dam wall all the way to the armature. These kinds of solicitations, even if they feature a low frequency, have a very important effect upon the built structure. The dam of Clucereasa is a small dam that uses two pumping stations that ensure the water supply for the Dacia-Renault Mioveni car plant and for the city of Mioveni. The dam maintenance was performed over time in acceptable limits and the infiltrations and deformations had remained within reasonable limits, being actually insignificant in case of clogging. For this instance, demolition works of the damaged concrete had been imposed by the usual procedure, followed by the restoration of the wearing concrete at the edge discharge and washing tunnels, reparation with ordinary concrete and the rock-fill embankment of the mobile berm. For the wearing concrete, a type of reinforced disperse concrete was used, having metallic fibers (MFC), obtained by introducing an amount of metallic fibers in the concrete’s composition as being prepared, this way obtaining a much more superior resistance.
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