Control of style-of-faulting on spatial pattern of earthquake-triggered landslides

Predictive mapping of susceptibility to earthquake-triggered landslides (ETLs) commonly uses distance to fault as spatial predictor, regardless of style-of-faulting. Here, we examined the hypothesis that the spatial pattern of ETLs is influenced by style-of-faulting based on distance distribution analysis and Fry analysis. The Yingxiu–Beichuan fault (YBF) in China and a huge number of landslides that ruptured and occurred, respectively, during the 2008 Wenchuan earthquake permitted this study because the style-of-faulting along the YBF varied from its southern to northern parts (i.e. mainly thrust-slip in the southern part, oblique-slip in the central part and mainly strike-slip in the northern part). On the YBF hanging-wall, ETLs at 4.4–4.7 and 10.3–11.5 km from the YBF are likely associated with strike- and thrust-slips, respectively. On the southern and central parts of the hanging-wall, ETLs at 7.5–8 km from the YBF are likely associated with oblique-slips. These findings indicate that the spatial pattern of ETLs is influenced by style-of-faulting. Based on knowledge about the style-of-faulting and by using evidential belief functions to create a predictor map based on proximity to faults, we obtained higher landslide prediction accuracy than by using unclassified faults. When distance from unclassified parts of the YBF is used as predictor, the prediction accuracy is 80%; when distance from parts of the YBF, classified according to style-of-faulting, is used as predictor, the prediction accuracy is 93%. Therefore, mapping and classification of faults and proper spatial representation of fault control on occurrence of ETLs are important in predictive mapping of susceptibility to ETLs

The ISRM suggested methods for rock characterization, testing and monitoring: 2007-2014

This book is a collection of ISRM suggested methods for testing or measuring properties of rocks and rock masses both in the laboratory and in situ, as well as for monitoring the performance of rock engineering structures. The first collection (Yellow Book) has been published in 1981. In order to provide access to all the Suggested Methods in one volume, the ISRM Blue Book was published in 2007 (by the ISRM via the Turkish National Group) and contains the complete set of Suggested Methods from 1974 to 2006 inclusive. The papers in this most recent volume have been published during the last seven years in international journals, mainly in Rock Mechanics and Rock Engineering. They offer guidance for rock characterization procedures and laboratory and field testing and monitoring in rock engineering. These methods provide a definitive procedure for the identification, measurement and evaluation of one or more qualities, characteristics, or properties of rocks or rock systems that produces a test result

Introductory longer review for rock mechanics testing methods

Rock mechanics involves characterizing the strength of rock material and the geometry and mechanical properties of the natural discontinuities of the rock mass. Rock engineering is concerned with specific engineering circumstances, for example, how much load will the rock support and whether reinforcement is necessary. Since the establishment of the International Society for Rock Mechanics (ISRM) in the 1960s, there have been important scientific developments and technological advances both in rock mechanics and rock engineering. Particularly, modeling of rock behavior, design methodologies for rock structures and rock testing methods are the main issues in these developments and advances. The models developed depend considerably on the input parameters such as boundary conditions and material, discontinuity and rock mass properties. For this reason, establishing how to obtain these input parameters for a particular site, rock mass and project is important. In this chapter, first, a brief historical account of material testing is given with a special emphasis on the evolution of testing of rocks. Next, rock mechanics testing methods including those for rock material, discontinuities and rock masses are critically reviewed in terms of laboratory and in-situ tests. Then, standardization of rock testing methods is mentioned within the context of the Suggested Methods (SMs) by the ISRM. Finally, current developments and future trends in rock testing methods are briefly discussed. © 2017 Taylor & Francis Group, London, UK

Suggested Methods for Rock Failure Criteria: General Introduction

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failures

The stability of slopes during and after excavation is always of great concern in the field of rock engineering. One of the structurally controlled modes of failure in jointed rock slopes is wedge failure. The limiting equilibrium methods for slopes under various conditions against wedge failure have been previously proposed by several investigators. However, these methods do not involve dynamic assessments and have not yet been validated by experimental results, In this paper, the tests performed on model wedges under static and dynamic loading conditions are described and the existing limiting equilibrium methods are extended to take into account dynamic effects. The applicability and validity of the presented method are checked through model tests carried out under well controlled conditions and by actual cases studied by the authors, both in Turkey and Japan

November 2011 and Associated Geotechnical Damages

Two devastating earthquakes (Van-Ercis, M(w)7.2 and Edremit, M(w)5.6) occurred in October and November 2011, respectively, in the Van Province of the eastern Turkey. In this study, the characteristics of both main shocks and their geo-engineering aspects are evaluated. Some computations and observations showed that the amount of lateral spreading is about 69 cm for an inclination of 3 % while it becomes about 19 cm for the inclination of 1 %. Probably amplification effect due to the Van-Ercis earthquake and slope height and angle might be the main reasons of natural slope failures. Although the magnitude of the Edremit earthquake was small, this is the first time for liquefaction occurred during an earthquake with a magnitude smaller than 5.9 experienced in Turkey

The Behaviour of Structures Built on Active Fault Zones: Examples from the Recent Earthquakes of Turkey

Scopu

How to infer the possible mechanism and characteristics of earthquakes from the striations and ground surface traces of existing faults

The instrumented period for earthquakes is relatively short to understand their mechanism and characteristics in many countries. Even at present time, there are many areas in the world where seismic instruments are still insufficient. Therefore, it is very difficult to know the mechanism and the characteristics of future earthquakes in any place because of either the lack of instrumentation and/or the shortness of the instrumented period. In this article, the authors present a methodology for inferring the possible mechanism and characteristics of earthquakes from the ground surface traces and striations of existing faults. The methodology is then applied to the faults of certain locations in Turkey and compared with actual observations in order to see its validity and applicability. © 2002, Japan Society of Civil Engineers. All rights reserved