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1.
Hazard analysis of seismic submarine slope instability 总被引：1，自引：0，他引：1
Rafael Rodríguez-Ochoa Farrokh Nadim José M. Cepeda Michael A. Hicks Zhongqiang Liu 《Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards》2015,9(3):128-147
To assess the risk associated with a submarine landslide, one must estimate the probability of slope failure and its consequences. This paper proposes a procedure to estimate the probability of earthquake-induced submarine slope failure (hazard) based on probabilistic seismic hazard analyses, ground response analyses and advanced laboratory tests. The outcomes from these analyses are treated in a probabilistic framework, with analytical simulations using mathematical techniques such as the first-order reliability method, Monte Carlo simulation and Bayesian updating. Fragility curves of slope failure during the earthquake (co-seismic) and after the earthquake (post-seismic) were developed in this study, and were shown to provide a clear and well-organized procedure to estimate the annual failure probability of a submarine slope under earthquake loading. 相似文献
2.
The assessment of rock-fall hazards is subject to significant uncertainty, which is not fully considered in general practice and research. This paper reviews and classifies the various sources of the uncertainty. Taking a generic framework for risk assessment as source, a probabilistic model is presented that consistently combines the different types of uncertainties, in order to obtain a unified estimate of rock-fall risk. An important aspect of the model is that it allows for incorporating all available information, including physical and empirical models, observations and expert knowledge, by means of Bayesian updating. Detailed formulations are developed for various types of information. Finally, two examples considering rock-fall risk on roads, with and without protection structures, illustrate the application of the probabilistic modeling framework to practical problems. 相似文献
3.
A formal Bayesian approach that uses the Markov chain Monte Carlo method to estimate the uncertainties of natural hazards has attracted significant attention in recent years, and a fuzzy graph can be considered an estimation of the relationship that we want to know in risk systems. However, the challenge with such approaches is to sufficiently consider uncertainty without much prior knowledge and adequate measurement. This paper proposes a new adaptive Bayesian framework that is based on the conventional Bayesian scheme and the optimal information diffusion model to more precisely calculate the conditional probabilities in the fuzzy graph for recognizing relationships and estimating uncertainty in natural disasters with scant data. This methodology is applied to study the relationship between the earthquake’s magnitude and the isoseismal area with strong-motion earthquake observations. It is also compared with other techniques, including classic Bayesian regression and artificial neural networks. The results show that the new method achieves better performance than do the main existing methods with incomplete data. 相似文献
4.
Mohammad Ashtari Jafari 《Natural Hazards》2007,42(1):237-252
The Bayesian probability estimation seems to have efficiencies that make it suitable for calculating different parameters
of seismicity. Generally this method is able to combine prior information on seismicity while at the same time including statistical
uncertainty associated with the estimation of the parameters used to quantify seismicity, in addition to the probabilistic
uncertainties associated with the inherent randomness of earthquake occurrence. In this article a time-independent Bayesian
approach, which yields the probability that a certain cut-off magnitude will be exceeded at certain time intervals is examined
for the region of Alborz, Iran, in order to consider the following consequences for the city of Tehran. This area is located
within the Alpine-Himalayan active mountain belt. Many active faults affect the Alborz, most of which are parallel to the
range and accommodate the present day oblique convergence across it. Tehran, the capital of Iran, with millions of inhabitants
is located near the foothills of the southern Central Alborz. This region has been affected several times by historical and
recent earthquakes that confirm the importance of seismic hazard assessment through it. As the first step in this study an
updated earthquake catalog is compiled for the Alborz. Then, by assuming a Poisson distribution for the number of earthquakes
which occur at a certain time interval, the probabilistic earthquake occurrence is computed by the Bayesian approach. The
highest probabilities are found for zone AA and the lowest probabilities for zones KD and CA, meanwhile the overall probability
is high. 相似文献
5.
A Probabilistic Modelling System for Assessing Flood Risks 总被引：4，自引：2，他引：4
In order to be economically viable, flood disaster mitigation should be based on a comprehensive assessment of the flood risk.
This requires the estimation of the flood hazard (i.e. runoff and associated probability) and the consequences of flooding
(i.e. property damage, damage to persons, etc.). Within the “German Research Network Natural Disasters” project, the working
group on “Flood Risk Analysis” investigated the complete flood disaster chain from the triggering event down to its various
consequences. The working group developed complex, spatially distributed models representing the relevant meteorological,
hydrological, hydraulic, geo-technical, and socio-economic processes. In order to assess flood risk these complex deterministic
models were complemented by a simple probabilistic model. The latter model consists of modules each representing one process
of the flood disaster chain. Each module is a simple parameterisation of the corresponding more complex model. This ensures
that the two approaches (simple probabilistic and complex deterministic) are compatible at all steps of the flood disaster
chain. The simple stochastic approach allows a large number of simulation runs in a Monte Carlo framework thus providing the
basis for a probabilistic risk assessment. Using the proposed model, the flood risk including an estimation of the flood damage
was quantified for an example area at the river Rhine. Additionally, the important influence of upstream levee breaches on
the flood risk at the lower reaches was assessed. The proposed model concept is useful for the integrated assessment of flood
risks in flood prone areas, for cost-benefit assessment and risk-based design of flood protection measures and as a decision
support tool for flood management. 相似文献
6.
Probabilistic earthquake risk assessment using CAPRA: application to the city of Barcelona, Spain 总被引：2，自引：2，他引：0
Mabel C. Marulanda Martha L. Carreño Omar D. Cardona Mario G. Ordaz Alex H. Barbat 《Natural Hazards》2013,69(1):59-84
The risk evaluation model CAPRA (Comprehensive Approach to Probabilistic Risk Assessment) is a techno-scientific methodology and information platform, composed of tools for evaluating and communicating risk at various territorial levels. The model allows evaluating losses on exposed elements using probabilistic metrics, such as the loss exceedance curve, the expected annual loss and the probable maximum loss, useful for multi-hazard risk analyses. In this article, the process of probabilistic seismic risk analysis is described, explaining the main features of the CAPRA modules of hazard, vulnerability and risk estimation applied to the city of Barcelona, Spain. In addition, according to the physical risk results and the information on the socioeconomic indicators of the city, this article presents the holistic evaluation of seismic risk, which is a valuable result to facilitate the integrated risk management by the different stakeholders involved in risk reduction decision making. 相似文献
7.
This is the second part of our study on the assessment of seismic hazard and seismic risk for Tulbagh, the settlement, located about 90 km N-E from Cape Town, where the strongest and most damaging earthquake known in the existing earthquake history of South Africa took place. This part of our study, which can be read independently from Part I, concentrates on the probabilistic seismic risk analysis (PSRA) forTulbagh. The work begins with an introduction and a historical perspective on the estimation of seismic damage to buildings. The methodology for the estimation of expected damage from a probabilistic point of view is then presented. The work closes with an application of the described methodology to a site in the vicinity of Tulbagh. 相似文献
8.
An integrated flood risk assessment model for property insurance industry in Taiwan 总被引：13，自引：11，他引：2
Hsu Wen-Ko Huang Pei-Chiung Chang Ching-Cheng Chen Cheng-Wu Hung Dung-Moung Chiang Wei-Ling 《Natural Hazards》2011,58(3):1295-1309
Taiwan is located in an area affected by Northwest Pacific typhoons, which are also one of the most important sources of rainfall
to the island. Unfortunately, the abundant rainfall brought by typhoons frequently produces hazards. In recent years, typhoons
and floods have caused serious damage, especially Typhoon Morakot in 2009. In this study, a probabilistic model is developed
based on historical events which can be used to assess flood risk in Taiwan. There are 4 separate modules in this model, including
a rainfall event module, a hydraulic module, a vulnerability module, and a financial loss module. Local data obtained from
the Taiwan government are used to construct this model. Historical rainfall data for typhoon and flood events that have occurred
since 1960, obtained from the Central Weather Bureau, are used for computing the maximum daily rainfall for each basin. In
addition, the latest flood maps from the Water Resources Agency are collected to assess the probable inundation depth. A case
study using the local data is carried out. Assessment is made to predict possible economic loss from different financial perspectives
such as the total loss, insured loss, and loss exceeding probabilities. The assessment results can be used as a reference
for making effective flood risk management strategies in Taiwan. 相似文献
9.
The use of the possibility theory to investigate the epistemic uncertainties within scenario-based earthquake risk assessments 总被引：1，自引：0，他引：1
This paper presents a methodology to represent and propagate epistemic uncertainties within a scenario-based earthquake risk
model. Unlike randomness, epistemic uncertainty stems from incomplete, vague or imprecise information. This source of uncertainties
still requires the development of adequate tools in seismic risk analysis. We propose to use the possibility theory to represent
three types of epistemic uncertainties, namely imprecision, model uncertainty and vagueness due to qualitative information.
For illustration, an earthquake risk assessment for the city of Lourdes (Southern France) using this approach is presented.
Once adequately represented, uncertainties are propagated and they result in a family of probabilistic damage curves. The
latter is synthesized, using the concept of fuzzy random variables, by means of indicators bounding the true probability to
exceed a given damage grade. The gap between the pair of probabilistic indicators reflects the imprecise character of uncertainty
related to the model, thus picturing the extent of what is ignored and can be used in risk management. 相似文献
10.
Urban earthquake disaster prevention is regarded as an integrated systematic engineering. Urban earthquake disaster prevention system is made up of all the earthquake disaster prevention activities. The concept and composition of urban earthquake disaster prevention system periphery were presented based on system periphery theory. A seismic risk-control mechanism model of system periphery was deduced using exchange rate of periphery as a dependent variable, and an observability–controllability model of system periphery was established and crystallized in its application to the quantitative analysis of practice problem. The input sets of urban earthquake disaster prevention system are determined as the maximum earthquake magnitude happened in or around the city, the measurable earthquake frequency, population density and fixed assets density. The inside state sets of urban earthquake disaster prevention system are determined as disaster resistant ability of buildings, disaster resistant ability of lifelines and investment dynamics in disaster prevention per urban built-up area. The system output is urban seismic risk. The calculative results show the model presented in this study can analyze the influence of system periphery intensity and inside state on seismic risk and can control urban seismic risk by adjusting the parameters of system periphery, the system inside state and human influence intensity. 相似文献
11.
Vulnerability index and capacity spectrum based methods for urban seismic risk evaluation. A comparison 总被引：3，自引：2，他引：1
This article contributes to the development and application of two latest-generation methods of seismic risk analysis in urban
areas. The first method, namely vulnerability index method (VIM), considers five non-null damage states, defines the action
in terms of macroseismic intensity and the seismic quality of the building by means of a vulnerability index. The estimated
damage degree is measured by semi-empirical functions. The second method, namely capacity spectrum based method (CSBM), considers
four no damage states, defines the seismic action in terms of response spectra and the building vulnerability by means of
its capacity spectrum. In order to apply both methods to Barcelona (Spain) and compare the results, a deterministic and a
probabilistic hazard scenario with soil effects are used. The deterministic one corresponds to a historic earthquake, while
the probabilistic seismic ground motion has a probability of exceedence of 10% in 50 years. Detailed information on the building
design has been obtained along years by collecting, arranging, improving, and completing the database of the dwellings of
the city. A Geographic Information System (GIS) has been customized allowing storing, analysing, and displaying this large
amount of spatial and tabular data of dwellings. The obtained results are highly consistent with the historical and modern
evolution of the populated area and show the validity and strength of both methods. Although Barcelona has a low to moderate
seismic hazard, its expected seismic risk is significant because of the high vulnerability of its buildings. Cities such as
Barcelona, located in a low to moderate seismic hazard region, are usually not aware of the seismic risk. The detailed risk
maps obtained offer a great opportunity to guide the decision making in the field of seismic risk prevention and mitigation
in Barcelona, and for emergency planning in the city. 相似文献
12.
Within the framework of the performance based earthquake engineering, site specific earthquake spectra for Van province has been obtained. It is noteworthy that, in probabilistic seismic hazard assessment, as a first stage data from geological studies and records from the instrumental period were compiled to make a seismic source characterization for the study region. The probabilistic seismic hazard curves were developed based on selected appropriate attenuation relationships, at rock sites, with a probability of exceedance 2, 10 and 50% in 50 yrs period. The obtained results are compared with the spectral responses proposed for seismic evaluation and retrofit of building structure in Turkish Earthquake Code (2007), section 7. The acceleration response spectrums obtained from probabilistic seismic hazard analysis are matched to adjust earthquake accelerograms recorded during the 2011 Van earthquakes by using SeismoMatch v2.0 software. The aim of this procedure is to obtain a set of reasonable earthquake input motions for the seismic evaluation of existing buildings. 相似文献
13.
Mabel C. Marulanda Omar D. Cardona Miguel G. Mora Alex H. Barbat 《Natural Hazards》2014,74(3):2071-2088
Understanding and evaluating disaster risk due to natural hazard events such as earthquakes creates powerful incentives for countries to develop planning options and tools to reduce potential damages. The use of models for earthquake risk evaluation allows obtaining outputs such as the loss exceedance curve, the expected annual loss and the probable maximum loss, which are probabilistic metrics useful for risk analyses, for designing strategies for risk reduction and mitigation, for emergency response strategies and for risk financing. This article presents, based on probabilistic risk models, the design and implementation of a risk transfer instrument to cover the private buildings of the city of Manizales, Colombia. This voluntary collective instrument provides financial protection to both, the estate tax payers and the low-income homeowners through a cross-subsidy strategy; besides, it promotes not only the insurance culture but also the solidarity of the community. The city administration and the insurance industry are promoting this program using the mechanism of the property tax payment. This collective insurance helps the government to access key resources for low-income householders recovery and improve disaster risk management at local level. 相似文献
14.
The hazard assessment of potential earthquake-induced landslides is an important aspect of the study of earthquake-induced landslides. In this study, we assessed the hazard of potential earthquake-induced landslides in Huaxian County with a new hazard assessment method. This method is based on probabilistic seismic hazard analysis and the Newmark cumulative displacement assessment model. The model considers a comprehensive suite of information, including the seismic activities and engineering geological conditions in the study area, and simulates the uncertainty of the intensity parameters of the engineering geological rock groups using the Monte Carlo method. Unlike previous assessment studies on ground motions with a given exceedance probability level, the hazard of earthquake-induced landslides obtained by the method presented in this study allows for the possibility of earthquake-induced landslides in different parts of the study area in the future. The assessment of the hazard of earthquake-induced landslides in this study showed good agreement with the historical distribution of earthquake-induced landslides. This indicates that the assessment properly reflects the macroscopic rules for the development of earthquake-induced landslides in the study area, and can provide a reference framework for the management of the risk of earthquake-induced landslides and land planning. 相似文献
15.
Gökhan Saygili 《Georisk: Assessment and Management of Risk for Engineered Systems and Geohazards》2017,11(2):197-207
The conventional liquefaction potential assessment methods (also known as simplified methods) profoundly rely on empirical correlations based on observations from case histories. A probabilistic framework is developed to incorporate uncertainties in the earthquake ground motion prediction, the cyclic resistance prediction, and the cyclic demand prediction. The results of a probabilistic seismic hazard assessment, site response analyses, and liquefaction potential analyses are convolved to derive a relationship for the annual probability and return period of liquefaction. The random field spatial model is employed to quantify the spatial uncertainty associated with the in-situ measurements of geotechnical material. 相似文献
16.
Evidence of self-organization in Sumatra earthquakes: recurrence time and its geodynamical implications 总被引：1，自引：1，他引：0
Risk reduction as an outcome only takes place if results of risk estimation studies are used to develop action plans for risk-management and risk-reduction strategies. This paper describes an automated model that uses the output of existing earthquake loss estimation methodologies to support decision makers in evaluating a set of competing seismic mitigation strategies and exploring their impact in reducing socio-economic losses of urban settlements. The proposed model is structured to quantify the monetary value of earthquake losses and to find an optimal budget allocation assigned to each mitigation strategy based on user input. The optimization method takes into account both pre- and post-earthquake expenditures, such as costs of building upgrades, critical facility enhancement, temporary shelter provisions, debris removal, hospitalization and human casualty. The system consists of five main modules: (1) building damage function; (2) mitigated damage function; (3) cost estimation function; (4) optimization function; and (5) user interface function. Whereas the optimization function provides the optimal values assigned to each mitigation alternative based on the estimated costs and a defined budget, the user interface allows the decision maker to interact with the software in each step and plan mitigation strategies that best suit the user’s socio-economic requirements and limitations. The outputs of the proposed model are presented with respect to an application in a pilot study area within a vulnerable city district of Tehran, Iran. 相似文献
17.
This article describes a new performance-based approach for evaluating the return period of seismic soil liquefaction based on standard penetration test (SPT) and cone penetration test (CPT) data. The conventional liquefaction evaluation methods consider a single acceleration level and magnitude and these approaches fail to take into account the uncertainty in earthquake loading. The seismic hazard analysis based on the probabilistic method clearly shows that a particular acceleration value is being contributed by different magnitudes with varying probability. In the new method presented in this article, the entire range of ground shaking and the entire range of earthquake magnitude are considered and the liquefaction return period is evaluated based on the SPT and CPT data. This article explains the performance-based methodology for the liquefaction analysis – starting from probabilistic seismic hazard analysis (PSHA) for the evaluation of seismic hazard and the performance-based method to evaluate the liquefaction return period. A case study has been done for Bangalore, India, based on SPT data and converted CPT values. The comparison of results obtained from both the methods have been presented. In an area of 220 km2 in Bangalore city, the site class was assessed based on large number of borehole data and 58 Multi-channel analysis of surface wave survey. Using the site class and peak acceleration at rock depth from PSHA, the peak ground acceleration at the ground surface was estimated using probabilistic approach. The liquefaction analysis was done based on 450 borehole data obtained in the study area. The results of CPT match well with the results obtained from similar analysis with SPT data. 相似文献
18.
Least square support vector machine and relevance vector machine for evaluating seismic liquefaction potential using SPT 总被引：4，自引：1，他引：3
Pijush Samui 《Natural Hazards》2011,59(2):811-822
The determination of liquefaction potential of soil is an imperative task in earthquake geotechnical engineering. The current
research aims at proposing least square support vector machine (LSSVM) and relevance vector machine (RVM) as novel classification
techniques for the determination of liquefaction potential of soil from actual standard penetration test (SPT) data. The LSSVM
is a statistical learning method that has a self-contained basis of statistical learning theory and excellent learning performance.
RVM is based on a Bayesian formulation. It can generalize well and provide inferences at low computational cost. Both models
give probabilistic output. A comparative study has been also done between developed two models and artificial neural network
model. The study shows that RVM is the best model for the prediction of liquefaction potential of soil is based on SPT data. 相似文献
19.
Earthquake vulnerability and seismic risk assessment of urban areas in high seismic regions: application to Chania City,Crete Island,Greece 总被引：2，自引：1，他引：1
The earthquake vulnerability and the seismic risk assessment for the urban center of Chania in the island of Crete is approached
through the development of a GIS-based application that takes into consideration the structural and geological domain of the
region. Considering a localized model, the various structural and geomorphologic attributes of the region were assigned specific
weights of significance that allowed the creation of a modular application that was tested for the city of Chania, and it
was verified based on the recent seismic activity of the area. The proposed risk map and model can become a significant tool
for confronting crises resulting from future earthquake incidences. 相似文献
20.
为了更好地把握溃坝洪水风险,减小因溃坝洪水而造成的人员生命和财产损失,建立了基于Godunov格式的一维、二维溃坝水流耦合数学模型。一维溃坝水流模型采用HLL格式的有限体积法求解,二维溃坝水流模型采用基于非结构网格的Roe格式离散求解,在一维、二维模型的链接处采用重叠计算区域的方法实现一维模型和二维模型之间的水力要素信息交换。经弯道溃坝算例和断面突变溃坝算例验证,该耦合模型具有良好的可靠性和适用性,验证后的耦合模型为大尺度的溃坝水流数值模拟打下了基础。 相似文献