Determination of Rock Slope Stability Using Stereographic Projection between Sulav and Amadiyah Resorts

Geological discontinuities play a significant role in the assessment of rock slope stability. Rock slope stability has been studied on the main road between Sulav and Amadiya resorts in Duhok governorate on the southern limb of Mateen anticline, to determine the expected rock slides on this road. Five (5) stations were chosen to study these rock slides that may occur on these steep slopes. All these stations within Pila Spi Formation that consists of hard dolomitic limestone and covering the areas from Sulav resort towards Amadiya district with a length of up to 2.5 Kms. The Stereographic analysis was used to study and classify the stability of these slopes. The analysis showed in all stations the possibility of plane sliding to happen on the bedding plane, and the wedge sliding between the bedding plane and planes of all joint sets, as well as the occurrence of rockfall on some stations.

An algorithm for the 3D ROck Slope Kinematic Analysis (ROKA) based on RPAS digital photogrammetry data.

<p>Among the several adopted methods for the kinematic analysis of the possible modes of failure that could affect a rock slope, the Markland test is the most used. Whereas, it has the advantage of being simple and fast, it has some limits, as the impossibility to manually consider the several different slope orientations and their interaction with the discontinuity dimensions and positions.</p><p>Recently, the improvements in the Remote Piloted Aerial System (RPAS) digital photogrammetry techniques for the development and mapping of Digital Outcrop Models (DOMs) have given the possibility of developing new automatized digital approaches. In this study, ROKA (ROck slope Kinematic Analysis) algorithm is presented. It is an open-source algorithm, written in MATLAB language, which aims to perform the kinematic analysis of the stability of a rock slope using the discontinuity measurements collected onto 3D DOMs. Its main advantage is the possibility to identify the possible critical combination between the 3D georeferenced discontinuities and the local surface of the slope. In particular, the critical combinations that can activate the planar sliding, flexural toppling, wedge sliding and direct toppling modes of failures can be detected and highlighted directly on the DOM. Hence, the ROKA algorithm can make the traditional approach for the kinematic analysis of a rock slope more effective, allowing not only to simplify the analysis, but also to increase its detail. This can be very important, in particular, for the analysis of large and complex rock slopes.</p>

Rock Slope Stability Assessment Along Rawanduz Main Road, Kurdistan Region

The rock slope instability along the Khalifan-Bekhal-Rawanduz main road has been studied in the southwestern limb of the Bradost anticline (Mountain) and both northeastern and southwestern limb of the Korek anticline (Mountain) in the northeast of the Erbil city, Kurdistan Region, Iraq. The major factors of the instability of the rock slopes in the study area are types of discontinuous and the degree of erosion. Ten stations have been chosen for fieldwork. The expected failure types that may occur along the road are plane sliding and wedge sliding. This research is mainly focused on the type of failure along the rock slope and the factor that affect the instability of the studied slopes and have found that they are slope orientation and geometry of the discontinuity. Different remediation methods are proposed for the studied rock slopes base on rock slope analysis. The rock slopes along the road require continuous monitoring because of their hazard conditions.

Impact of Geological Structures on Rock Slope Stability in The NW Nose (Plunge ) of Surdash Anticline, Sulaimaniya/ NE Iraq

The road network in Surdash anticline is considered as an important road network connecting lower Dukan town with the touristic upper Dukan town. Dukan lake plays an important role in the social and economic activities of Dukan town and the surrounding areas.For assessing the stability of the rock slopes in the area, 9 stations were selected along the upper Dukan road on both sides of Surdash anticline, and their stability was evaluated by the kinematic analysis using DIPS V6.008 software. Kinematic analysis of the studied stations shows thatplanar sliding is possible in stations No. 1, 2, 3 and 8, while wedge sliding is possible in station No. 5, 6, 7 and 9b. The other stations (No. 4and 9a) are stable. Tectonic structures played an extra paradoxical role in the stability of the rock slopes and the type of failure. In most ofthe selected stations , the geological structure had a negative role, which supported or promoted the failure in the study area. However, in few stations , it had a positive role and converted the slope from unstable to stable conditions. In addition, the presence of incongruent minor syncline folds, especially in the SW-limb of themajor anticline, led to the occurring of wedge sliding instead of plane sliding.

Rock Mass Characterization and Stability Evaluation of Mount Rushmore National Memorial, Keystone, South Dakota

The purpose of this study was to characterize the rock mass at Mount Rushmore National Memorial (MORU) and to evaluate the stability of the presidential sculptures. The sculptures are carved in granite, but quartz-mica schist and minor outcrops of pegmatite are also present within the site area. We divided the MORU area into four “regions” to collect discontinuity data. Since the sculptures were not accessible during this study, we used light detection and ranging (LiDAR) data and Split-FX software to determine the orientations of both the discontinuities and the slopes on the sculptures. The rock mass characterization results, using both the Rock Mass Rating system and the Q-system, indicate the granite, schist, and pegmatite classify as fair to good rock. Kinematic analysis results indicate that the potential for planar, wedge, and toppling failures exists for various slopes on each of the sculptures. The factor of safety (FS) values against planar and wedge sliding, ignoring cohesion, range from 0.1 to 0.8 and from 0.2 to 1.3, respectively. Since failures have not been observed at the memorial, we back-calculated the amount of cohesion required to raise the FS values to >1. The back-calculation results show that both cohesion and friction contribute to stability of the sculptures. Using the Slide program, we performed an overall slope probabilistic analysis for the slopes on which the MORU sculptures are located. The analysis determines the mean factor of safety (FSM), reliability index (RI), and probability of failure (PF) for the slopes. For the static condition, the analysis resulted in FSM, RI, and PF values ranging from 3.3 to 4.5 percent, 3.3 to 7.8 percent, and 0 percent, respectively. With a seismic load coefficient of 0.14 applied to the slopes, the corresponding values were: 2.6 to 4.1 percent, 2.9 to 4.7 percent, and 0 percent. For both the static and seismic conditions, the results indicate that, overall, the slopes of the sculptures are stable.

Interaction of a Sliding Wedge and a Metallic Specimen With a Near-Surface Inhomogeneity

The problem of a hard wedge sliding against a metal substrate has been studied extensively for its importance in tribo-plasticity and deformation processing. Here we explore the effect of introducing a single, near-surface plastic inhomogeneity (termed as a pseudograin) in a metal substrate using Lagrangian finite element (FE) analysis. The pseudograin is allowed to be softer or harder than the surrounding material. The effects of sliding parameters like the size and location of the pseudograin, friction and indenter geometry are also studied. Interestingly, the introduction of the pseudograin can lead to production of surface folds / self-contacts, and acutely-inclined, near-surface, crack-like features, which cannot be reproduced by homogeneous specimens. In fact, this tribosystem is phenomenologically very rich, despite differing from classical triboplastic systems of Challen, Oxley and Torrance only by way of the inhomogeneity. Despite its simplicity, the model replicates several experimentally observed features of surface folding, and is a minimal model to obtain folding in sliding. The occurrence of surface folds and concomitant residual surface damage points to the important role played by microstructure-related inhomogeneities in determining surface quality in deformation processing operations (e.g. repeated sliding to generate UFG surfaces) and is also a potentially new mode of sliding wear.