Claim Missing Document
Check
Articles

Found 30 Documents
Search

CORRELATION BETWEEN OVERALL SLOPE AND SLOPE STABILITY OF HIGHWALL IN PIT TUNGGAL, BORNEO MANIK, VITO ARISTO; NINGRUM, WIWIN JUNITA; KHOIRULLAH, NUR; SOPHIAN, RADEN IRVAN; ZAKARIA, ZUFIALDI
Journal of Geological Sciences and Applied Geology Vol 3, No 1 (2019): Journal of Geological Sciences and Applied Geology
Publisher : Faculty of Geological Engineering, Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/gsag.v3i1.22030

Abstract

Slope stability is an important aspect of the mining operation. Hence, an in-depth understanding of slope stability and variable that affect it is very crucial.  This research was conducted in pit tunggal, Borneo. The aim of this research is to identify the correlation between overall slope and slope stability in highwall slope at pit tunggal. Slope stability analysis was conducted with SLIDE V 6.00 software using Morgenstern-Price’s limit equilibrium method. The result of this research shows that, as the highwall slope gets steeper, the slope stability represented by a factor of safety (FS) may decrease. Otherwise, when the highwall slope gets declivous, the factor of safety may increase.
SOIL ERODIBILITY AND ITS EROSION POTENTIAL IN SADAWARNA DAN AND SURROUNDING AREA, CIBOGO DISTRICT, SUBANG REGENCY, WEST JAVA PROVINCE Alpionisa, Salsabila Nur; Zakaria, Zufialdi; Khoirullah, Nur; Sophian, Raden Irvan; Firmansyah, Yusi
Journal of Geological Sciences and Applied Geology Vol 7, No 2 (2023): Journal of Geological Sciences and Applied Geology
Publisher : Faculty of Geological Engineering, Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/gsag.v7i2.49995

Abstract

The Sadawarna Dam and its surroundings, which are located in Subang Regency, are currently under construction. Change in land use caused by the construction occurred. Land management and soil conservation are needed to prevent uncontrolled erosion because it can caused slopes in critical condition, flood occurred in the downstream areas of river, and silting of dam. One of the information in land management and soil conservation is by identifying the soil erodibility which aims to find out the sensitivity of the soil to erosion in the research area. Soil erodibility affected by grain size distribution, soil structure, soil organic matter, and soil permeability. In this research area, the soil erodibility was calculated based on disturbed sample in the field which was then tested in the laboratory. The laboratory tests include sieve analysis, hydrometer analysis, and %c organic. Soil permeability obtained from previous studies. The research area is dominated by clay-sized soil which are the result of weathered claystone in Subang Formation. Soil erodibility value in the research area ranged from 1,100 – 0,448 t ha h/ha MJ cm with dominance of low soil erodibility classes. The dominance of clay-sized soil causes low soil erodibility value because clay sized soil has cohesive properties so it tends to be difficult to erode.
Potential Collapse Based on Discontinuity Plane In The Andesite Quary Of Mount Geulis, Jatinangor District, Sumedang Regency, West Java Taufiq, Mochamad Muslim; Sophian, Raden Irvan; Khoirullah, Nur; Zakaria, Zulfialdi
Journal of Geological Sciences and Applied Geology Vol 5, No 2 (2021): Journal of Geological Science and Applied Geology
Publisher : Faculty of Geological Engineering, Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/gsag.v5i2.34878

Abstract

Landslide are natural disasters that often occur in West Java, in 2020 landslides have occurred 852 times. In an effort to prevent the occurrence of rock landslides, it is necessary to study the stability of rock slopes, so it is necessary to evaluate the discontinuity of the rock and take engineering geological. The purpose of this study is to analyze the stability of rock slopes in the study area so that the types of landslides that can occur can be known. Method used is Kinematic Analysis where the object of research is an andesite outcrop located at the northwest foot of Mount Geulis, Cinanjung Village, Jatinangor District. Kinematic analysis is an analysis of the movement of objects without considering the forces that cause them. Various types of slope failure are associated with geological structures that result in a discontinuity plane in the rock body. The results of the study are in the form of determining the potential for landslides that can occur in the research area. Based on the kinematic analysis of the types of failure in the research area that can occur are wedge types in the MT-2, MT-5, and MT-6 segments and toppling types in the MT-3, MT-4, MT-7 segments and Planar failure found in the MT - 1 segment. potential failure in the study area are toppling and wedge with percentage values for the possibility of landslides were obtained, namely: wedge failure is 1.82% - 3.91% and toppling failure is 21.82% - 38.95% and Planar failure is 55.81%
Slope Stability Analysis of East Ring Road Construction at Sadawarna Dam With Shear Strength Reduction Method Putra, Rafino Kurnia; Zakaria, Zufialdi; Alfadli, Muhammad Kurniawan; Sophian, Raden Irvan; Khoirullah, Nur; Firmansyah, Yusi
Journal of Geological Sciences and Applied Geology Vol 7, No 3 (2023): Journal of Geological Sciences and Applied Geology
Publisher : Faculty of Geological Engineering, Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/gsag.v7i3.50589

Abstract

Slope stability has been a problem that studied on geotechnical works for the uncertainties such as varieties of soil behaviours to unpredicted failure of measurements and samplings. The Limit Equilibrium Method (LEM) has been popular for decades for its convenience but cannot determine displacement thus the result could be uncertain. As computational calculations have been developed, the Finite Element Method (FEM) began to use as a tool to not only determine factor of safety, but also determine displacement and forces that affect slope’s stability. This research was done to analysed slope stability using Shear Strength Reduction (SSR) and compared it to general method such as Limit Equilibrium Method (LEM). The research was conducted on a section in Sadawarna DAM ring road area, Subang, West Java. Slope on research area was divided into two layers with the bottom layer relatively non-cohesive compared to the top of layer. Both soil however dominantly consist with fine grain soil such as silt and clay. The upper layer of slope can contain more water with liquid limit of 73,46% compared to the lower layer with 68,27% liquid limit.  Simulation result showed slope that analysed using SSR method has Factor of Safety (FoS) 0,12 lower than LEM method. SSR method could be used to analysed pessimistic value at worst scenario and could predicted deformation of slope.
Brief Communication: Rapid Assessment of landslide events based on UAV photogrametry: The 9 January 2021 Cimanggung Landslide, Sumedang, Indonesia Abdurrahman, Ali; Budipraja, Muhammad Ariq; Khoirullah, Nur; Helmi, Faisal; Sophian, Raden Irvan
Journal of Geological Sciences and Applied Geology Vol 4, No 2 (2021): Journal of Geological Science and Applied Geology
Publisher : Faculty of Geological Engineering, Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/gsag.v4i2.32063

Abstract

The landslide incident in Cisarua Village, Cimanggung District on January 9, 2021, is one of the natural disasters which is quite concerning to see the victims. This short mapping is focused on seeing changes in the shape of the affected area and slope faces before the landslide and after the incident. The brief mapping uses the DJI Mavic Pro model UAV that flies at an altitude of 50 meters and 150 meters above the ground with an overlap of 80% and covers an area of 3 ha. Aerial photo processing will produce output in the form of orthophoto images and digital elevation models (DEM) of landslide affected areas. The result of geometric observation showed that the land surface was covered with an area of 3,789 m2. The measured flat length ranges from 120 meters and 32 meters wide. There is also a slope angle after and before the landslide of 2.8 degrees. Analysis of the causes of landslides in terms of geomorphological aspects shows the landslide affected areas that are right in the hilly valleys coupled with buildings that cover the surface water flow from high rainfall. In addition, the analysis of the causes of technical geological analysis shows that landslides can occur due to differences in soil types with different physical properties so that the two soils are not bound by cohesion forces between soils.
SOIL SLOPE REINFORCEMENT USING CANTILEVER RETAINING WALL ON THE WEST RING ROAD OF SADAWARNA DAM, SUBANG DISTRICT Rizki, Afdal; Alam, Boy Yoseph Cahya Sunan Sakti Syah; Khoirullah, Nur; Sophian, Raden Irvan; Firmansyah, Yusi
Journal of Geological Sciences and Applied Geology Vol 7, No 3 (2023): Journal of Geological Sciences and Applied Geology
Publisher : Faculty of Geological Engineering, Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/gsag.v7i3.50433

Abstract

The research was conducted in the West Ring Road of Sadawarna Dam, Subang Regency. This research aims to provide recommendations for the design of cantilever retaining wall to increase the value of the slope safety factor in the research area. Calculation of the value of the slope safety factor uses the limit equilibrium method with the Janbu calculation method. In actual conditions, the value of the slope safety factor shows an unstable value referring to SNI 8460:2017, namely in static conditions with a vehicle load is 1.31 and in pseudostatic conditions with a vehicle load is 1.083. Slope strengthening was carried out using cantilever retaining wall. The retaining wall design that has been made meets the criteria for stability against overturning, stability against sliding, and stability for the bearing capacity of the soil. The safety factor value for slope with retaining wall shows a stable FS value referring to SNI 8460:2017, namely 1.53 in static conditions with vehicle loads and 1.11 in pseudostatic conditions with vehicle loads. Keyword: slope, safety factor, retaining wall, cantilever
The Effect of Surface Water On The Slope Of “X” Housing Gunung Geulis, Cimanggung District, Sumedang Regency Putri, Revena Denia; Sophian, Raden Irvan; Zakaria, Zufialdi; Khoirullah, Nur
Journal of Geological Sciences and Applied Geology Vol 5, No 2 (2021): Journal of Geological Science and Applied Geology
Publisher : Faculty of Geological Engineering, Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/gsag.v5i2.34638

Abstract

Rainfall intensity can affect water infiltration to the ground. The increase in groundwater level will increase pore pressure (μ) that minimizes shear resistance of the slope mass, especially on the ground material (soil). The increase in surface water levels also increases surface water discharge and increases erosion below the surface (piping or subaqueous erosion). As a result of more subtle friction (silt) from the time that washed away soil, the soil will decrease future resilience. This happened in Subdistrict Cimanggung, Sumedang, West Java. This area is composed of weathered soil of volcanic products such as tuff, volcanic breccia, and andesitic lava. The parameters of this research contain basic properties and mechanical properties of soil, slope profile in MH soil, and water surface level. This research aims to determine basic properties and mechanical properties of soil, as well as the effects of groundwater level, that can give recommendations for groundwater level to get a stable condition of the slope. The basic properties and mechanical properties of soil are known based on laboratory tests from a disturbed and undisturbed soil sample were obtained by surface sampling and geotechnical hand drilling. Slopes were analyzed by the Bishop method using Rockscience Slide software. The result is there’s an increase in the value of safety factors when the level of surface water level decrease. From the value of the safety factor that varies between slope sections, that slope can be stable if water surface level -7,5 meters beneath the surface.
Analysis of Tectonic Control Using Order and Bifurcation Ratio Madani, Ghoffar Cahya; Sophian, Raden Irvan; Khoirullah, Nur
Journal of Geological Sciences and Applied Geology Vol 5, No 1 (2021): Journal of Geological Science and Applied Geology
Publisher : Faculty of Geological Engineering, Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/gsag.v5i1.34639

Abstract

Quantitative geomorphological can be analyzed using watersheds morphometric aspect. Morphometry can be interpreted as a quantitative aspect of watersheds or parameters of watershed characteristics that can be measured and calculated. This research was shown to determine the tectonic control of the research area with the approach of the morphometric aspect of watershed. Aspect of watershed morphometry used in this research consist of river order and bifurcation ratio (Rb), drainage density (Dd), asymmetry factor (Af), mountain front sinuosity (Smf) and watershed shape index (Bs). The method used in this research is the studio method by processing Digital Elevation Model data using Arcmap software. Based on the results obtained, there are 4 sub-watersheds in the research area that have different calculation values. Sub-Watershed 1 has an Af value is (66,025), Smf value is (1.43 – 4.56), and Bs value is (1,002). Sub-Watershed 2 has an Af value is (51,398), Smf value is (1.38 – 3), and Bs value is (0.907). Sub-Watershed 3 has an Af value is (49,536), Smf value is (1.17 – 2.91), and Bs value is (0.933). Sub-Watershed 4 has an Af value is (60,407), Smf value is (1.8 – 3), and Bs value is (1,486). Based on all the calculation results, the relative tectonic activity index (IATR) value is 3 which belongs to class 4 which indicates low tectonic activity in the research area. This is also supported by the calculation of the bifurcation ratio where only a small part of the river segment is affected tectonics, meaning most of the others are not active tectonically.
LOWWALL SLOPE STABILITY OF PANEL 32 AND PANEL 36 PT. XYZ, SOUTH KALIMANTAN Jamil, Aliyuddin; Sophian, Raden Irvan; Rendra, Pradnya Paramarta Raditya
Journal of Geological Sciences and Applied Geology Vol 7, No 1 (2023): Journal of Geological Science and Applied Geology
Publisher : Faculty of Geological Engineering, Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/gsag.v7i1.48196

Abstract

The research was conducted in the coal mining area of PT. XYZ, South Kalimantan. The research aims to create a geological model for each cross-section according to the characteristics of materials and to calculate the slope stability of the lowwall slope. The researcher calculated the slope stability using Morgenstern-Price method with Rocscience Slide2 software. The geological conditions of the study area are composed of alternating sandstones with coal-inserted claystone and coal-inserted claystone from the Warukin Formation. Material properties at the study area are composed of sandstone, claystone, and coal. The results of the slope stability simulation show that the lowwall panel 32 slope has a safety factor value of 1.081 while the lowwall panel 36 slope has a safety factor value of 1.107.
EFFECT OF BEDDING PLANES ON SLOPE STABILITY IN COAL OPEN MINE PT. PAMAPERSADA NUSANTARA DISTRICT ASMI, CENTRAL KALIMANTAN Akbar, Faisal; Sophian, Raden Irvan; Muslim, Dicky; Manullang, Sahala
Journal of Geological Sciences and Applied Geology Vol 4, No 1 (2020): Journal of Geological Science and Applied Geology
Publisher : Faculty of Geological Engineering, Universitas Padjadjaran

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24198/gsag.v4i1.29069

Abstract

Bedding planes are one of the distinctive features of an open coal mine. The presence of the bedding planes can be a slip surface on a slope that has a dip direction relatively in the same direction as the bedding planes. Kinematic analysis for open pit slopes is one important aspect of the influence of the bedding planes in minimizing the occurrence of landslides. The purpose of this research is to explain the effect of the presence of bedding planes on slope stability. The method used is secondary data collection, field observations, and kinematic analysis. The results showed that the slopes of the study area were composed of sandstone, claystone, siltstone, carbonaceous claystone, and coal. Carbonanaceous claystone as a weakly layer. The rock bedding area on this slope has a strike/dip N 288 ° E / 17 °, while the slope of the research has an overall slope 29 ° and a slope dip direction N 15 ° E. The dip direction value that is relatively unidirectional between the bedding planes and the slope of the research with a difference of 3 ° can be the cause of the slip surface and is prone to landslides. Thus, the slopes of the study area have the potential plane failure so that geotechnical engineering is needed in the next mining process to ensure slope stability.