Design of Overall Slope Angle and Analysis of Rock Slope Stability of Chadormalu Mine Using Empirical and Numerical Methods

A structural and engineering geological study of rock slope stability was carried out in six stations that lie in the Southwest of Baranan mountain, along Sirwan road. The rock slopes and discontinuities were surveyed at each of these stations, and the relationships with failures were determined. The slopes were classified on the basis of (Al-Saadi, 1981), and the rocks were described in engineering terms according to (Anon, 1972) and (Hawkins, 1986), Stereographic projection was made using software (GEOrient 9.5.0) to represent the field data that were recorded in order to understand the situation in the six stations (sites) that were chosen along Sirwan road near Darbandikhan dam, the failures' types were recorded during field study were rock fall, toppling, and sliding. The study also revealed that the factors affecting slope stability in the study area were slope angle, height, dip of strata, and discontinuities. The laboratory test of the rock samples (point-load test) showed that the average value of compressive strength of the rock for the study area is about 181.29 MPa.Some measures are proposed to stabilize the slopes in the mentioned stations including; the removal of blocks liable to toppling in the critical cases (sites 2 and 6), casing the slopes with covenant materials such as concrete (site 4) and gabions (sites 2 and 6), with construction of retaining walls and digging of protective trenches to protect the slopes and reduce their hazard on the road (site 1, 3, and 5).

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Methodology to evaluate rock slope stability under seismic conditions at Solà de Santa Coloma, Andorra

Natural Hazards and Earth System Science ◽

10.5194/nhess-9-1763-2009 ◽

2009 ◽

Vol 9 (6) ◽

pp. 1763-1773 ◽

Cited By ~ 18

Author(s):

O. Mavrouli ◽

J. Corominas ◽

J. Wartman

Keyword(s):

Slope Stability ◽

Rock Slope ◽

Limit Equilibrium ◽

Water Pressure ◽

Slope Angle ◽

Water Levels ◽

Equilibrium Analysis ◽

Rock Slope Stability ◽

Ground Acceleration ◽

Moderate Seismicity

Abstract. An analytical methodology is presented to evaluate rock slope stability under seismic conditions by considering the geomechanical and topographic properties of a slope. The objective is to locate potential rockfall source areas and evaluate their susceptibility in terms of probability of failure. For this purpose, the slope face of a study area is discretized into cells having homogenous aspect, slope angle, rock properties and joint set orientations. A pseudostatic limit equilibrium analysis is performed for each cell, whereby the destabilizing effect of an earthquake is represented by a horizontal force. The value of this force is calculated by linear interpolation between the peak horizontal ground acceleration PGA at the base and the top of the slope. The ground acceleration at the top of the slope is increased by 50% to account for topographic amplification. The uncertainty associated with the joint dip is taken into account using the Monte Carlo method. The proposed methodology was applied to a study site with moderate seismicity in Solà de Santa Coloma, located in the Principality of Andorra. The results of the analysis are consistent with the spatial distribution of historical rockfalls that have occurred since 1997. Moreover, the results indicate that for the studied area, 1) the most important factor controlling the rockfall susceptibility of the slope is water pressure in joints and 2) earthquake shaking with PGA of ≤0.16 g will cause a significant increase in rockfall activity only if water levels in joints are greater than 50% of the joint height.

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ENGINEERING GEOLOGICAL ASSESSMENT OF THE ROCK SLOPE STABILITY ALONG THE PROPOSED LERABIRE ROAD IN THE MERGASUR CITY, KURDISTAN, IRAQ

Iraqi Geological Journal ◽

10.46717/igj.53.2f.5ms-2020-12-28 ◽

2020 ◽

Vol 53 (2F) ◽

pp. 65-82

Author(s):

Rebaz Qader

Keyword(s):

Slope Stability ◽

Rock Slope ◽

Slope Angle ◽

Rock Slope Stability ◽

Rock Slopes ◽

Stability Of Slopes ◽

The Stability ◽

High Degree ◽

Marly Limestone ◽

Failure Possibility

The study of slope stability along the proposed Lerabire road in the Mergasur town, in Erbil city, Kurdistan region of NE-Iraq is carried out. To evaluate the stability of slopes, twenty stations were selected along the mentioned road, two stations in the rock slopes of the Shiranish Formation, eleven stations in the Bekhme Formation, six stations in the Qamchuqa Formation, and one station in the Sarmord Formation. In this study, the stability of rock slopes has been evaluated by the Landslide Possibility Index system. The results of the Landslide Possibility Index category in the rock slopes along the proposed Lerabire road ranges from a very low to low for rock slopes in stations 1 and 2 (marl and marly limestone of the Shiranish Formation, Moderate for rock slopes in stations 3, 4 and 19 (limestone of the Bekhme Formation), High for rock slopes in the stations 5, 6, 7, 8, 9, 10, 11 (limestone of the Bekhme Formation), stations 12, 17 (limestone and marly limestone of the Qamchuqa Formation), station 20 (limestone of the Sarmord Formation and very high for rock slopes in the stations 13, 14, 15, 16 (limestone and marly limestone of the Qamchuqa Formation), station 18 (limestone of the Bekhme Formation). According to Landslide Possibility Index category, the hazard category is Low in station 1 in the Shiranish Formation, but in station 2, 3, 4 and 19 are Moderate, moreover, in the station 5, 11, 12, 17, 18 and 20 are high. The rock slope assessment indicated that the height of the slope face, slope angle, a high degree of weathering, and discontinuities spacing are the factors that increase the failure possibility. To prevent landslide the ditch method is used in the Shiranish Formation rock slopes, the reinforcement techniques are used in the Behkme Formation rock slopes and rock removal methods are used in Qamchuqa and Sarmord Formation rock slopes.

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