Rock glaciers are one of the distinct geomorphology feature are seen in medium size at Sabalan mountain slope. Active Rock glaciers represent the existence of Alpine permafrost, and on the other hand these features sigificant tools for palaeoclimate reconstructing. About 14 Rock glaciers at the North slope of Sabalan at the height of between 3460 and 4400m S.L. has been distinguished. That about cover an area of 6.29 km. Tongue-shaped Rock glaciers with 85.1 percent have the highest spread than lobate Rock glaciers with 14.3 percent. Their area varies from 0.05 to 1.64 km, and their formation at present time depends on the regional topoclimate. By using the RILA and RLA concepts their origin has been distinguished. On the basis of their moving rate in a year the probable age of active Rock glaciers can be estimated between 3000-6000 years.

The slope Mass Rating (SMR) system is a widely used method by geoengineers and geologists to assess the stability of Rock slopes, such as those found along highways, in mines, or near dams. It helps evaluate the likelihood of slope failure and identify any necessary measures to prevent Rock instabilities. In this study, the SMR classification system was applied to analyze the stability of 10 slopes in the Azarshahr province, located in northwest Iran. Each slope underwent a standard geotechnical investigation, including the collection of block samples, which were tested using index Rock mechanics methods such as uniaxial compressive strength (UCS), point-load tests, and Schmidt hammer rebound tests. The SMR classification results revealed that the slopes in Azarshahr range from partially stable to completely stable. Potential failures were linked to the development of joints, wedges, or blocks, with varying levels of risk. Where necessary, occasional support systems were recommended to improve stability. These findings offer important insights into the region's slope stability and provide guidance for potential mitigation strategies.

Surface and internal characteristics of tongue-shaped Rock glacier have been studied at the north slope of Haram summit on interior Sabalan Mountain. The formation of surface depressions indicates the existence of a solid ice core, and its origin also is determined by using RILA concept. It is probable that a normal glacier has been buried beneath a cover debris. The vertical section of this Rock glacier shows three layers from bottom to top, and based on the dynamic criterion, the Rock glacier is an active one.

Inhomogeneity and discontinuities play a key role in the resistance and behavior of Rock masses. Today engineers have a wide range of methods to analyze the stability of Rock slopes. Due to its simplicity and speed of evaluation, static analysis methods continue to play a special role in the stability assessment of jointed Rock slopes. One of the most well-known static methods used in the stability analysis of Rock slopes is the Key Block method (KBM), which is based on key block finding and analysis. In this method, if none of the key blocks are unstable, it implies that Rock mass is stable. Occasionally, the combination of several stable blocks has led to the formation of a group of blocks that sometimes leads to instability. Therefore, the stability analysis of the jointed Rock masses leads to study groups of blocks that are potentially dangerous for the stability of a Rock slope. The Key Group method (KGM), with its progressive approach, finds these critical groups and focuses the stability calculations on these groups. Until now, methods SKGM, PKGM, OKGM have been proposed to remove the limitations of this method and its development. In order to increase the efficiency, accuracy, and speed of this method and to develop it in three dimensions, it is decided to combine it with one of the numerical methods. The standard Discontinuous Deformation Analysis method (DDA) is an implicit method based on the finite element method. This is a sophisticated numerical method for modeling the quasi-static and dynamic behavior of Rock block systems in discontinuous Rock masses. The goal of this paper is to use the potency of the numerical method of DDA to analyze the candidate key group. For this purpose, the DDA computer program was developed with Mathematica programming language and combined with the KGM software. The resulting package, after selecting the key group by the KGM method, proceeds to analyze it with the DDA method. Two examples are solved illustrating the reasonable results and the efficiency of this developed method compared to that of the original KGM and SKGM. The results validated the proper accuracy and good performance of the procedure developed in this research.

Where closely jointed Rock masses are encountered in slopes, failure can occur both through the Rock mass, as a result of combination of macro and micro jointing, and also through Rock substance. Determination of the strength of these Rock masses is quite difficult since the size of representative specimens of them is too large for laboratory testing. This difficulty can be overcome by using a non-linear Rock mass failure criterion or by back analysis of such slopes. In this paper, a new procedure, and accompanying computer program, is presented for estimation of shear strength parameters, mobilized in slopes cut, in closely jointed Rock masses, which obey a non-linear failure criterion, rather than a linear one. In this procedure, the necessary constants to calculate normal stress are dependent to shear strength parameters of the failed Rock masses. These parameters can be determined, using a main cross section across the failed slope, without the need for exact value of Geological Strength Index (GSI). In this respect, trials are made with different GSIm and GSIs values, corresponding to various possible combinations of the constant m and s, satisfying the limit equilibrium condition, used in the Hoek & Brown’s failure criterion. The proposed procedure provides a quick check for the GSI obtained from the site investigations. The proposed procedure is used in conjunction with the Morgenstern-Price method of slope analysis, for circular or noncircular slip surfaces. The method outlined in this paper has been satisfactorily applied to Duna landslide, in the right bank of upper dam of Siah Bishe pump-storage, north of Iran.

This paper is intended to show the use of Discontinuous Deformation Analysis (DDA) in stability analysis of Rock slopes. In general, static stability analysis methods for Rock slopes mainly derived from the limit equilibrium concepts that are very tedious in computation and not safe for dynamic loading. The Discontinuous Deformation Analysis (DDA) method that has been developed by Shi is one of the most advanced methods that can be applied in this case. To improve the capability of the Shi's method to meet the requirements for analysis of Rock slopes under earthquake loading, some improvements have been applied to the original program. The main improvements are time dependent (time history) loading, damping and energy loss for which some numerical examples are presented to show the capabilities of the modified program.

Rock slope stability is a crucial component of geotechnical engineering, aimed at ensuring the safety and integrity of both natural and artificial slopes within Rock formations. This study aims to classify Rock slopes based on stability using the Qslope method, an approach originally developed by Bar and Barton in 2017 and later modified by Azarafza et al. in 2020 to accommodate data from Iran. For this research, 12 jointed Rock slopes in the Semirom region of Iran were selected as case studies. The analysis revealed that most of these slopes are in stable or uncertain conditions, while two were identified as unstable. The findings underscore the utility of the Qslope method as a fast and efficient tool for assessing Rock slope stability. This method offers practical advantages for geotechnical engineers, as it streamlines the evaluation process, especially in regions where geological data may be limited or difficult to obtain. Ultimately, the study contributes valuable insights into slope stability management in Iran, while also confirming the broader applicability of the Qslope method to various geographical contexts.

Due to the uncertainties in input geometrical properties of fractures, there is no unique solution for assessing the stability of slopes in jointed Rock masses. Therefore, the necessity of applying probabilistic analysis is inevitable on these cases. In this study, a probabilistic analysis procedure along with relevant algorithms were developed using Discrete Fracture Network-Distinct Element Method (DFN-DEM) approach. In the right abutment of Karun 4 dam and downstream, five joint sets and one major joint were identified. According to the geometrical properties of fractures in the Karun river valley, instability situations seemed applicable on this abutment. In order to evaluate the stability of a Rock slope, different combinations of joint set geometrical parameters were selected, and a series of numerical DEM simulations were performed on generated and validated DFN models in DFN-DEM approach to measure minimum required support patterns in dry and saturated conditions. Results indicate that the distribution of required bolt length was well fitted with a lognormal distribution in both circumstances. In dry conditions, the calculated mean value was 1125.3 m, and more than 80 percent of models needed only 1614.99 m of bolts which was equivalent to a bolt pattern of 2 m spacing and 12 m length. However, as for the slopes with saturated condition, the calculated mean value was 1821.8 m, and more than 80 percent of models needed only 2653.49 m of bolts which was equivalent to a bolt pattern of 15 m length and 1.5 m spacing. Comparing the obtained results with that of numerical and empirical methods show that the investigation of a slope stability with different DFN realizations which were conducted in different block patterns was more efficient than the empirical methods.

On the north-side of Phase 7 gas flare site located in South Pars Gas Complex (SPGC), Assalouyeh, Iran has a discontinuous Rock slope that due to tectonic activity has been vertical mode folded. Also, the coastal climate caused to weathering of mass and occurring toppling failure in this slope. This instability causes some problems in accessing the flare site. So, this slope need to stability analysis and stabilization. In order to stability analysis of this discontinuous Rock slope, utilized the distinct elements method (DEM). The modelling process of toppling failures in UDEC is divided to geometrical and mechanical modelling. The result of modelling has good agreement with the toppling failures definition and process.

Landslides are deceitful natural disasters, resulting in the loss of human life, collapse of engineering structures, and the natural environment on the earth. Therefore, the aims of this study to assess, predict and mapping of susceptible landslide hazard map using GIS based software. Six landslide causative factors including aspect, distance from stream, lithology, plan curvature, slope and elevation selected as influencing factor for landslide occurrences. The landslide frequency ratio calculated using the probability technique. The controlling elements graded using a statistical and frequency ratio methodology based on GIS. The landslide hazard map shows 27% (4. 8 km2) is no-danger zone, with 588 (41%) families living there. A medium to landslide danger zone covers 29% (5. 2 km2), with 555 families (38. 7%) living. A low-risk landslide zone covers 23% (4. 1 km2), with 228 (16%) families living. A high-risk landslide zone covers 21% (3. 8 km2), with 61 (4. 3%) families living. The prediction rate of all factors revealed that, the highest landslide occurrence associated with Lithology and plan curvature. When these are added with high rainfall intensity, the magnitude of the landslide increases. The highest prediction accuracy of 89. 58% found from combination of all causative factors which depicts how well the model and factors accurately forecast landslides.