Estudo de caso: injeções de calda de cimento para impermeabilização e consolidação de fundação de barragem

Abstract

During the stage of the viability study for the implementation of Small Hydroelectric Power Plants, it is of fundamental importance to have knowledge about how it is composed and how the rock mass is presented, in the area of interest, since it will be responsible for supporting the loads resulting from the construction of the structures that compose them. In addition to presenting good mechanical resistance, another very important factor that must be observed is the definition of a foundation treatment that aims to reduce percolation through the dam foundation, thus making the structure safer, since percolation and the resulting pressures are significant sources of instability and one of the biggest problems in relation to dam safety. In this course conclusion work, a study on cement grouts is presented, which were used as a method of treatment of foundation in the small hydroelectric power plant Cachoeira Cinco Veados, located in the central region of Rio Grande do Sul, showing how the process took place. for the execution of perforations and cement grout injections, both in the form of a curtain, for waterproofing, and in specific points for the consolidation of the rock mass under the dam foundation. From the analyzes carried out, compliance with the requirements requested in NBR 7681:2013 and the expected compressive strengths for the cement grout applied is shown. Information on tests and activities carried out along the injection curtain are also presented. Thus, it can be concluded that the rock mass presented low permeability and that the injected cement grouts eached the compressive strengths specified for the construction of the PCH.