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Geotechnical design is evolving to adopt the limit state design (LSD) philosophy, also known as reliability-based design (RBD). This is evident by its inclusion in geotechnical design codes (e.g. Eurocode 7). Partial factors are often used in design codes to overcome the difficulty in performing probabilistic analysis suggested by the RBD. The increasing use of RBD suggests a need to investigate the applicability of design with partial factors for various rock engineering structures; this paper will investigate their application in the design of support for a rock wedge in an underground opening. The paper provides a critical overview of the design philosophy of RBD, the components necessary for its application, and the methods by which the probability of failure may be computed. In addition, it discusses how partial factors are calibrated from RBD and how code development can be subsequently performed. This is put into context with a design example for the support of a rock wedge. [ABSTRACT FROM AUTHOR]

Abstract The paper presents new isotope geochronological data for several mineral deposits, ore occurrences, and related igneous bodies (plutons and dikes) in the Verkhoyansk-Kolyma folded area, eastern Yakutia. Twenty-one 40Ar/39Ar mica and four U-Pb zircon dates provide the first age constraints on key metallogenic units in the area. The dating results allow correlation between tectonic, magmatic, and metallogenic events. The sampled mineral deposits within the Adycha-Taryn fault zone in the southeastern Verkhoyansk-Chersky orogen apparently formed at the Jurassic-Cretaceous boundary during the final phase of the collision between the Siberian (North Asian) craton and the Kolyma-Omolon microcontinent (Kupol'noe deposit and the early metallogenic pulse of the Malotarynskoe deposit, ~ 143-144 Ma) and in the latest Early Cretaceous, in the beginning of the orogen collapse (Tallalakh and Dora-Pil' deposits and the Malotarynskoe late metallogenic pulse, ~ 126 Ma). According to the suggested new classification of metallogenic units, these deposits belong to the Late Jurassic-Early Cretaceous Yana-Kolyma metallogenic belt. The Kyuchus deposit (~ 106 Ma), the Deputatsky ore cluster (~ 106-113 Ma), and the Khotoidokh deposit (~ 116 Ma) in the northern Verkhoyansk-Kolyma folded area belong to the North Verkhoyansk metallogenic belt. Their origin was associated with accretional and collisional processes that produced the Novosibirsk-Chukotka orogen in the middle Cretaceous. The Mangazeya ore cluster (~ 100 Ma, Early-Late Cretaceous boundary) in the southwestern end of the North Tirekhtyakh magmatic transverse belt belongs to the West Verkhoyansk metallogenic belt. The Nezhdaninskoe, Zaderzhnoe, Kurum, and Kuta deposits of the South Verkhoyansk area (~ 125-120 and ~ 100-95 Ma) can be joined into a single Verkhoyansk-Okhotsk metallogenic belt. The belt resulted from accretion and collision along the East Asian active continental margin and the related formation of the South Verkhoyansk orogen in the Early Cretaceous. [ABSTRACT FROM AUTHOR]

Prediction of coastal erosion is a challenging field of research with immense application potential in coastal management plans. In the present study, we simulated coastal morphological changes that occurred under normal and extreme wave conditions during a four-month winter monsoon period along a pocket beach at Yarada near Visakhapatnam city. We used Xbeach, a process-based numerical model to simulate the morphological changes by forcing the model with buoy observed wave parameters. Initial beach topography was generated from DGPS profiles surveyed in November 2014 at regular spatial intervals. Model simulated changes in the beach elevation due to accretion and erosion are validated by DGPS profiles re-surveyed in March 2015. During the four-month period, the net sediment transport at Yarada is generally southerly and becomes strong during high wave activity inducing erosion at the northern sector and accretion at the southern sector. The model has simulated the changes in elevation with a high degree of accuracy for the eroded northern sector, and with some disparity along the accreted southern sector. The swash and nearshore processes responsible for the coastal erosion were found to exist throughout the simulation period and intensified during the high wave condition. The paper highlights the importance of modelling studies for conceptual understanding of the beach response to normal and extreme conditions, and for identifying vulnerable sectors of a beach so that appropriate measures can be taken to prevent coastal erosion and loss of land. [ABSTRACT FROM AUTHOR]