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.

A Generalized Stochastic Framework for Analyzing Rock Slopes Stability and Designing Reliable Remedial Measures with Limited Investigation Data: Theory and Field Implementation

Availability of limited data for rock properties is a very frequently encountered issue for the rock slopes along Himalayan highways due to problems like high costs, manual efforts, geological complexities, difficult terrain etc. involved in rock testing and investigation. Under these conditions, support estimation for rock slides mitigation using traditional deterministic and reliability approaches becomes highly questionable due to inaccuracy in the estimated statistical parameters of rock properties. To resolve this issue, this article proposes a computationally efficient methodology which utilizes Advanced Re-Sampling Reliability Approach (ARRA) along with deterministic approach and Target Reliability Approach (TRA) to estimate required support for rock slides mitigation when limited field and laboratory investigation data is available, with acceptable accuracy and confidence. Proposed methodology was used to design the support measures to mitigate two massive rock slides along a rock-slide prone highway i.e. Rishikesh-Badrinath National Highway (NH-58) in India. It was observed from the analysis that availability of limited test data induces high uncertainty in the statistical parameters (mean and standard deviation) and probability distribution of rock properties. Support estimation carried out using traditional deterministic and reliability approaches with this inaccurate probabilistic characterization of rock properties, can lead to inaccurate support estimates for potential rock slides in the presence of limited data; however these methods when coupled with ARRA can lead to significant improvement in computational efficiency and the designer’s confidence for the estimated support.

Rockfall Analyses at Km 13+550 in the New Road of Vlora, Albania

Rockfall dynamics is a complex function of the location of the detachment point and the geometry and mechanical properties of both the block and the slope. Theoretically, knowing the initial conditions, the slope geometry, and the relationships describing the energy loss at impact or by rolling, it should be possible to compute the position and velocity of a block at any time. Nevertheless, relevant parameters are difficult to ascertain both in space and time, even for an observed event. Usually, the geometrical and geomechanically properties of the blocks (size, shape, strength, fracturing) and the slope (gradient, length and roughness, longitudinal and transversal concavities and convexities, grain size distribution, elastic moduli, water content, etc.), and the exact location of the source areas are unknown. In this paper, the sources of potential rock fallings involve a rocky area including between km 13+550 and km 13+600 in the new road of Vlora city in Albania. The area is characterized by a rock ridge, shaped like a dome, located few tens of meters above the design road. The purpose of this paper is the rock slope analysis. This analysis consists mainly of defining the sources of falling rocks, estimating the causes (by toppling, rock slides, single blocks) the size, the geometry, and type of blocks, the structural arrangement of joints, etc.

Development of smart boulders to monitor mass movements via the Internet of Things: A pilot study in Nepal

Boulder movement can be observed not only in rock fall activity, but also in association with other landslide types such as rock slides, soil slides in colluvium originated from previous rock slides and debris flows. Large boulders pose a direct threat to life and key infrastructure, amplifying landslide and flood hazards, as they move from the slopes to the river network. Despite the hazard they pose, boulders have not been directly targeted as a mean to detect landslide movement or used in dedicated early warning systems. We use an innovative monitoring system to observe boulder movement occurring in different geomorphological settings, before reaching the river system. Our study focuses on an area in the upper Bhote Koshi catchment northeast of Kathmandu, where the Araniko highway is subjected to periodic landsliding and floods during the monsoons and was heavily affected by coseismic landslides during the 2015 Gorkha earthquake. In the area, damage by boulders to properties, roads and other key infrastructure, such as hydropower plants, is observed every year. We embedded trackers in 23 boulders spread between a landslide body and two debris flow channels, before the monsoon season of 2019. The trackers, equipped with accelerometers, can detect small angular changes in boulders orientation and large forces acting on them. The data can be transmitted in real time, via a long-range wide area network (LoRaWAN®) gateway to a server. Nine of the tagged boulders registered patterns in the accelerometer data compatible with downslope movements. Of these, six lying within the landslide body show small angular changes, indicating a reactivation during the rainfall period and a movement consistent with the landslide mass. Three boulders, located in a debris flow channel, show sharp changes in orientation, likely corresponding to larger free movements and sudden rotations. This study highlights that this innovative, cost-effective technology can be used to monitor boulders in hazard prone sites, identifying in real time the onset of movement, and may thus set the basis for early warning systems, particularly in developing countries, where expensive hazard mitigation strategies may be unfeasible.