Otimização da impermeabilidade do núcleo de uma barragem de terra com base no coeficiente 𝑛/LIV.

Abstract

The need to reserve water for multiple uses, using earth dams, is common practice in Brazil. Containment of water by the Embankment must reduce water outlets by the downstream slope, in order to guarantee the dammed volume and the work’s safety. Thus, the present research analyzed the influence the insertion of a nucleus, with improved soil, in the water’s amount percolated through the mass of a zoned earth dam. A flow analysis was performed using SEEP/W (finite element based software) for a composite of 75% Botucatu sandstone residual soil and 25% dry weight basalt crushing residue of 16.0, 17.2 and 18.5 kN/m³. It has a trapezoidal nucleus with a base smaller than 8 meters and the largest base variable: 20, 45 and 70 meters and with the following mass-specific weight variables, with lime’s additions of 5, 7 and 9%. With the leakage results for each simulation, the applied calibration content has no direct influence on the percolation reduction, but the apparent dry weight in the paper nucleus in this phenomenon. With an analysis of the porosity/lime ratio (/Liv 0,12), the use of the higher the porosity of the material, the greater the percolation and the lower the effect of the cementing agent on the nucleus A unique curve related to /Liv 0,12percolated leakage can be adjusted for each nucleus size. Thus the applicability of the /Liv coefficient proves to be efficient in optimizing the core with regard to the optimization of the shaped core, cementitious material content and material porosity, all as a function of the maximum percolation flow rate adopted.