ANALISIS FAKTOR KEAMANAN GEOMETRI LERENG DISPOSAL DAN MENGETAHUI JUMLAH VOLUME DISPOSAL OPTIMAL

Abstract

Slope stability relating to the erosion which is the process of land mass transfer naturally from a high place to a lower place. The slope stability is influenced by several factors: the distance of ground water, the angle of slope, the strong value of soil shear and the type of constituent layer soil which has the value of cohesion and the angle of different friction. This research aimed to determine the slope stability which is shown in the value of safety factor for determining dumping limit boundary and to discover optimal disposal volume limit. The stages of the process of slope stability analysis were conducted by using Fellenius method, which is in the process of analysis using Geoslope/W software. The parameters used were the friction angle, cohesion, and the density of the soil. To calculate the amount of disposal volume used cross-sectional method. Based on the analysis of both section A and B using Fellenius method obtained the value of safety factors including the stable slopes; that is, the slope of section A-A from a distance of 10 meters to 50 meters obtained the Fk value = 1.298, 1.291, 1.285, 1.264, 1.241. The slopes of section B-B from a distance of 10 meters to 50 meters obtained the Fk value = 1.294, 1.292, 1.263, 1.250, 1.248. The spacious obtained from the cross section A to B = 897 m2, from the cross section C to D = 3,055 m2, and from the cross section E to F = 4,584 m2. Of the cross-sectional area will be obtained by the amount of disposal volume by which can be accommodated disposal. The dumping limit recommended by the calculation of the safety factor which has been calculated is a maximum of > 15 m of each crest of disposal slope design and the number of the optimal overburden volume which can be accommodated by disposal of 222,834 m3.