Analisis Bentuk Geometri Terhadap Stabilitas Lereng Pada Tambang Terbuka Dari Aspek Geoteknik

Abstract

Aceh Province is one of the coal producers, especially Sumber Batu Village in Meurebo District, West Aceh Regency. In the implementation of coal mining, it is necessary to pay attention to the slope stability of open-pit mining to identify and estimate the possibility of landslides. For this reason, the author conducted research in analyzing the geometric shape of the slope stability with the slope variance of modeling the reduction of the existing angle αeks - 10% to the depth of three layers of soil 11 meters. The 1st layer of soil is 1.5 meters, the second layer of soil is 2.5 meters, and the third layer of soil is 7 meters. Slope stability is strongly influenced by the geometric shape of the slope and the strength of soil parameters. To identify the stability of the slope against slope failure, computationally performed using the finite element method with Plaxis software as the reference for the value of FK 1.25, which is considered safe/stable, meaning that collapse rarely occurs. In this research, primary data is used in the form of direct observation in the field, namely taking soil samples to obtain soil data in the form of soil physical properties and soil mechanical properties into soil parameter data, which is tested in the soil laboratory. Secondary data used are map data, boring data, and Sondir data. Soil parameter data were processed using Plaxis software. The results of the slope stability analysis showed that by modeling the geometric shape of the slope (αeks - 10%) on the open slope of a coal mine with a soil depth of 11 meters, the FK value was 3.60. From the results of the FK scores, it shows that the slope of the slope is 3.60 1.25 above the reference value of safe/stable FK. The FK value is 0.2 greater than the FK existing geometry. The conclusion of this study is that geometric shapes play an important role in determining the stability of an open coal pit excavation slope. The smaller the slope angle, the greater the FK value obtained, or the more gentle the slope, the higher the safety value of a slope.

Slope Stability Technical Study Using Slope Mass Rating (Smr) Method at Pt. Karya Sumber Alam Perkasa, Sanggau Regency, Kalimantan Barat

“…The calculation of the safety factor is as follows: The value of the safety factor in pit 2 (two) is 2.458. These results show that the pit 2 (two) slope is in a stable condition because the FK value is > 1.25 (Table 5), which means that the resisting force of the pit 2 (two) slope is greater than the driving force (Bowles, 1984;Andriani et al., 2017;Nurhidayat et al., 2019;Fianti et al., 2014Fianti et al., ). 2020Cahyono, 2021).…”

“…Based on Figure 5, it can be concluded that the greater the cohesion value and the internal shear angle, the greater the strength of the material to resist landslides (Juwinda, 2019;Fianti et al, 2020). The greater the cohesion value, the greater the quality of the rock mass because the greater the cohesion value means, the greater the attraction between rock particles.…”

“…Technical studies are carried out to reduce the impact arising from stability risks (Cahyono, 2021). The impact of slope stability risks can be in the form of injury, equipment damage, production stops, and other impacts (Azizi et al, 2012;Juwinda, 2019;Fianti et al, 2020). Unstable slopes are hazardous (Bria and Isjudarto, 2015;Juwinda, 2019).…”

“…Therefore, it is necessary to conduct a slope stability study (Bria and Isjudarto, 2015;Madora et al;2016;Patinsyah et al, 2021). Stable slope conditions can maximize mining operations, optimal reserve recovery, and ensure occupational safety and health (K3) (Nurhidayat et al, 2019;Awal et al, 2020;Fianti et al, 2020;Sukardi and Hariyadi, 2021;Patinsyah et al, 2021). This research aims to examine the effect of rock mass class on slope stability, potential type of failure, and potential slope stability.…”

Increase in Safety Factor Value in Existing Conditions and Reinforcement of Gabion Type Retaining Wall Pt. Medco E&P Malaka Block A

“…The slope where the slide occurs has a safety factor value that is not fulfilled, namely SF (safety factor) ≤1.25 (Sadat, 2018). Febrianti (2016) states that a stability analysis with an SF value ≥ 1 means that the excavation/fill slope is safe and for an SF value ≤ 1 indicates that the excavation/fill slope is not safe. Munirwansyah (2014) states that more land movements or landslides occur due to the capability factor of human resources that ignores natural factors such as topography, soil temperature, and weather which are closely related to balance, which is called the storie index factor.…”