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Abstract: Building hazard assessment prior to earthquake occurrence exposes interesting problems especially in earthquake prone areas. Such an assessment provides an early warning system for building owners as well as the local and central administrators about the possible hazards that may occur in the next scenario earthquake event, and hence pre- and post-earthquake preparedness can be arranged according to a systematic program. For such an achievement, it is necessary to have efficient models for the prediction of hazard scale of each building within the study area. Although there are subjective intensity index methods for such evaluations, the objective of this paper is to propose a useful tool through fuzzy logic (FL) to classify the buildings that would be vulnerable to earthquake hazard. The FL is a soft computing intelligent reasoning methodology, which is rapid, simple and easily applicable with logical and rational association between the building-hazard categories and the most effective factors. In this paper, among the most important factors are the story number (building height), story height ratio, cantilever extension ratio, moment of inertia (stiffness), number of frames, column and shear wall area percentages. Their relationships with the five hazard categories are presented through a supervised hazard center classification method. These five categories are “none”, “slight”, “moderate”, “extensive”, and “complete” hazard classes. A new supervised FL classification methodology is proposed similar to the classical fuzzy c-means procedure for the allocation of hazard categories to individual buildings. The application of the methodology is presented for Zeytinburnu quarter of Istanbul City, Turkey. It is observed that out of 747 inventoried buildings 7.6%, 50.0%, 14.6%, 20.1%, and 7.7% are subject to expected earthquake with “none”, “slight”, “moderate”, “extensive”, and “complete” hazard classes, respectively. [Copyright &y& Elsevier]

This paper outlines a framework for risk assessment of landslides triggered by earthquakes and rainfall in urban buildings in the city of Medellín - Colombia, applying a model that uses a geographic information system (GIS). We applied a computer model that includes topographic, geological, geotechnical and hydrological features of the study area to assess landslide hazards using the Newmark's pseudo-static method, together with a probabilistic approach based on the first order and second moment method (FOSM). The physical vulnerability assessment of buildings was conducted using structural fragility indexes, as well as the definition of damage level of buildings via decision trees and using Medellin's cadastral inventory data. The probability of occurrence of a landslide was calculated assuming that an earthquake produces horizontal ground acceleration ( A h ) and considering the uncertainty of the geotechnical parameters and the soil saturation conditions of the ground. The probability of occurrence was multiplied by the structural fragility index values and by the replacement value of structures. The model implemented aims to quantify the risk caused by this kind of disaster in an area of the city of Medellín based on different values of A h and an analysis of the damage costs of this disaster to buildings under different scenarios and structural conditions. Currently, 62% of “Valle de Aburra” where the study area is located is under very low condition of landslide hazard and 38% is under low condition. If all buildings in the study area fulfilled the requirements of the Colombian building code, the costs of a landslide would be reduced 63% compared with the current condition. An earthquake with a return period of 475 years was used in this analysis according to the seismic microzonation study in 2002. [ABSTRACT FROM AUTHOR]

This paper presents a systematic review of peer-reviewed journal articles, scientific reports, books and research theses covering tsunami hazard, assessment and risk in Aotearoa‐New Zealand (A–NZ). Fifteen electronic databases were examined using an array of keyword search strings to comprehensively gather all available sources of information spanning 1868–2012 AD. 222 references were identified as directly relevant to tsunami hazard, assessment and risk in A–NZ with a further 51 references identified by scrutinising the original 222 references. The amount of information as well as the emphasis of the science contained in these 273 references differs greatly between documents. A meta-analysis of this collective scholarship shows six principal areas of scientific endeavour: (i) observation and cataloguing of modern and historical tsunami impacts caused by earthquakes and landslides, (ii) modelling and evaluation of near- and far-field generated tsunamis, (iii) detailed mapping and assessment of offshore seismic and other geological structures responsible for near-field tsunami generation, (iv) investigation and cross-referencing of Holocene palaeo-records of tsunami deposits preserved in wetlands, dunes and other coastal landforms, (v) survey and reconnaissance of modern and historical tsunami impacts, and (vi) guidance for tsunami hazard mitigation, preparedness and land-use planning. Synthesising all of these references, it is clear that A–NZ has been affected by remote, regional and locally generated tsunami during the historic, pre-written and pre-human periods. Further, scientific knowledge of tsunami risk and the forces responsible for tsunami generation has greatly improved. However, in spite of the many scientific advances detailed in this review, much more remains to be done to better understand and deal with the diverse tsunami hazard and risk facing A–NZ. [ABSTRACT FROM AUTHOR]

Abstract: Earthquake hazard assessment of existing buildings is among the most important issues for pre- and post-earthquake warning, preparation, vulnerability, and mitigation works. In any potential earthquake prone area, it is necessary to classify the existing building stoke into different categories according to rapid, simple, reliable, logical and expert view based models and software. This paper presents a soft computation methodology based on the fuzzy logic model (FLM) and system principles for the classification of buildings into five distinctive but mutually inclusive classes in terms of fuzzy sets as “without”, “slight”, “moderate”, “heavy”, and “complete” hazard categories. The preliminary modeling stages in reinforced concrete building evaluation against possible earthquakes of magnitude seven or over in Istanbul City municipality area are presented with specific emphasis on existing building grading. The essence of this model is the fuzzy logic with its logical rule bases and inference system methodology. Visually assessable variables, namely, storey number, cantilever extension, soft storey, weak storey, building quality, pounding effect, hill-slope effect, and peak ground velocity are considered as inputs with a single output variable as earthquake hazard category. The model inputs and outputs are fuzzified with expert views and logical implications (fuzzy-rules, associations) are proposed between the input variables and output. The application of the proposed model is presented for 1249 existing reinforced concrete buildings on the European side of Istanbul, Turkey. It is found that about 49% of the buildings fall within the “complete” and “heavy” hazard categories. Majority of the buildings falls in the “moderate” hazard category. [Copyright &y& Elsevier]

Abstract: The impact of earthquakes in urban centers prone to disastrous earthquakes necessitates the analysis of associated risk for rational formulation of contingency plans and mitigation strategies. In urban centers the seismic risk is best quantified and portrayed through the preparation of ‘Earthquake damage and Loss Scenarios’. The components of such scenarios are the assessment of the hazard, inventories and the vulnerabilities of elements at risk. For the development of earthquake risk scenario in Tashkent–Uzbekistan and Bishkek–Kyrgyzstan an approach based on spectral displacements is utilized. This paper will present the important features of a comprehensive study, highlight the methodology, discuss the results and provide insights to the future developments. [Copyright &y& Elsevier]

This paper focuses on origin, morphology and evolution of seven landslide dams in southeastern Sicily. These landforms are part of a set of 146 landslides recently recognised in this area, which was hitherto considered to have little or no slope instability. Southeastern Sicily consists of a plateau (the Hyblaean Mountains) incised by canyons and surrounded by lower lands. It is underlain mostly by subhorizontal, moderately to well-lithified carbonate rocks. Relief is low.Several lines of evidence justify the assumption of a seismic trigger for the landslides in this area: (1) the geo-climatic environment is not favourable to landsliding, (2) low-angle basal shear surfaces are very frequent, (3) landslide distribution is consistent with the known magnitude–distance relationships for earthquake-induced landslides, (4) historical documents testify to earthquake-triggered slope instability and (5) a specific landslide can be exactly dated.The phenomena illustrated here include six rock slides (one with a debris-flow component) and one rock fall. Slip surfaces are mostly non-circular. Landslide volume ranges from about 50×103 to 34×106 m3.With reference to the Costa and Schuster [Geol. Soc. Am. Bull. 100 (1988) 1054] classification of landslide dams, five cases belong to type II (spanning the entire valley), and two to type IV (failures from both valley sides, with frontal or side contact between failed masses). With reference to Crozier and Pillans [Catena 18 (1991) 471] classification of landslide lakes, all cases show a main valley lake while tributary valley, back and supra lakes are sporadically present. One damming is attributable to the 1693 earthquake with certainty; another damming, to the same earthquake with high probability. Three dams were reincised, one breached or reincised, one is slightly reincised and two more or less intact; correspondingly, five silting up deposits were reincised, one is being reincised at present and two are still under formation. [Copyright &y& Elsevier]

• Performance can be significantly improved without stiffening the entire building. • Relative contribution of transient and permanent drift damage to the total is key. • For repair cost, stiffness increase is most effective regardless of building period. • For loss of function, strength increase is more effective for longer period buildings. • Increasing partition drift capacity is a viable alternative to stiffness and strength. Building seismic performance plays an important role in earthquake resilience. This role can be characterized beyond safety and collapse prevention, which are the primary building code objectives, by evaluating the loss of function and costs of repair of buildings. One important measure for building performance evaluation is the damage that occurs when structural and nonstructural elements are deformed beyond their capacity during an earthquake. Through a risk-based performance evaluation procedure, the expected impact of changes in stiffness, strength, and deformation capacity on building damage can be quantified and the results can be utilized to make targeted improvements to building codes to enhance earthquake resilience. In this paper, models of 4, 7, 10, and 15-story reinforced concrete special moment frame structures designed for San Francisco are subjected to suites of earthquake ground motion records to evaluate deformation response for a range of earthquake intensities. From these analyses the statistics of demand are estimated and used, along with models of capacity and seismic hazard, to evaluate the expected repair costs and loss of function over the life of each building. Performing this analysis for a range of values for each design variable will demonstrate the influence of stiffness, strength, and deformation capacity on building seismic performance, which can be used for evaluating and enhancing community resilience. [ABSTRACT FROM AUTHOR]