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1.
Al Hoceima is one of the most seismic active regions in north of Morocco. It is demonstrated by the large seismic episodes reported in seismic catalogs and research studies. However, seismic risk is relatively high due to vulnerable buildings that are either old or don’t respect seismic standards. Our aim is to present a study about seismic risk and seismic scenarios for the city of Al Hoceima. The seismic vulnerability of the existing residential buildings was evaluated using the vulnerability index method (Risk-UE). It was chosen to be adapted and applied to the Moroccan constructions for its practicality and simple methodology. A visual inspection of 1102 buildings was carried out to assess the vulnerability factors. As for seismic hazard, it was evaluated in terms of macroseismic intensity for two scenarios (a deterministic and probabilistic scenario). The maps of seismic risk are represented by direct damage on buildings, damage to population and economic cost. According to the results, the main vulnerability index of the city is equal to 0.49 and the seismic risk is estimated as Slight (main damage grade equal to 0.9 for the deterministic scenario and 0.7 for the probabilistic scenario). However, Moderate to heavy damage is expected in areas located in the newer extensions, in both the east and west of the city. Important economic losses and damage to the population are expected in these areas as well. The maps elaborated can be a potential guide to the decision making in the field of seismic risk prevention and mitigation strategies in Al Hoceima. 相似文献
2.
Iran is one of the most seismically active countries of the world located on the Alpine-Himalayan earthquake belt. More than
180,000 people were killed due to earthquakes in Iran during the last five decades. Considering the fact that most Iranians
live in masonry and non-engineered houses, having a comprehensive program for decreasing the vulnerability of society holds
considerable importance. For this reason, loss estimation should be done before an earthquake strikes to prepare proper information
for designing and selection of emergency plans and the retrofitting strategies prior to occurrence of earthquake. The loss
estimation process consists of two principal steps of hazard analysis and vulnerability assessment. After identifying the
earthquake hazard, the first step is to evaluate the vulnerability of residential buildings and lifelines and also the social
and economic impacts of the earthquake scenarios. Among these, residential buildings have specific importance, because their
destruction will disturb the daily life and result in casualties. Consequently, the vulnerability assessment of the buildings
in Iran is important to identify the weak points in the built environment structure. The aim of this research is to prepare
vulnerability curves for the residential buildings of Iran to provide a proper base for estimating probable damage features
by future earthquakes. The estimation may contribute fundamentally for better seismic performance of Iranian societies. After
a brief review of the vulnerability assessment methods in Iran and other countries, through the use of the European Macroseismic
method, a model for evaluating the vulnerability of the Iranian buildings is proposed. This method allows the vulnerability
assessment for numerous sets of buildings by defining the vulnerability curves for each building type based on the damage
observations of previous earthquakes. For defining the vulnerability curves, a building typology classification is presented
in this article, which is representative of Iranian building characteristics. The hazard is described in terms of the macroseismic
intensity and the EMS-98 damage grades have been considered for classifying the physical damage to the buildings. The calculated
vulnerability indexes and vulnerability curves show that for engineered houses there is not any notable difference between
the vulnerability of Iranian and Risk-UE building types. For the non-engineered houses, the vulnerability index of brick and
steel structures is less than the corresponding values of the other unreinforced masonry buildings of Iran. The vulnerability
index of unreinforced and masonry buildings of Iran are larger than the values of the similar types in Risk-UE and so the
Iranian buildings are more vulnerable in this regard. 相似文献
3.
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
4.
In this paper, seismic risk scenarios for Bucharest, the capital city of Romania, are proposed and assessed. Bucharest has one of the highest seismic risk levels in Europe, and this is due to a combination of relatively high seismic hazard and a building stock built mainly before the devastating Vrancea 1977 earthquake. In this study, the seismic risk of Bucharest is assessed using the most recent information regarding the characteristics of the residential building stock. The ground motion amplitudes are evaluated starting from random fields obtained by coupling a ground motion model derived for the Vrancea intermediate-depth seismic source with a spatial correlation model. The seismic risk evaluation method applied in this study is based on the well-known macroseismic method. For several structural typologies, the vulnerability parameters are evaluated based on a damage survey performed on 18,000 buildings in Bucharest after the March 1977 earthquake. Subsequently, the risk metrics are compared with those from other studies in the literature that apply a different risk assessment methodology in order to gain a better view of the uncertainties associated with a seismic risk study at city level. Finally, the impact of several Vrancea intermediate-depth earthquake scenarios is evaluated and the results show that the earthquake which has the closest epicenter to Bucharest appears to be the most damaging.
相似文献5.
In this paper, seismic risk scenarios for Bucharest, the capital city of Romania, are proposed and assessed. Bucharest has one of the highest seismic risk levels in Europe, and this is due to a combination of relatively high seismic hazard and a building stock built mainly before the devastating Vrancea 1977 earthquake. In this study, the seismic risk of Bucharest is assessed using the most recent information regarding the characteristics of the residential building stock. The ground motion amplitudes are evaluated starting from random fields obtained by coupling a ground motion model derived for the Vrancea intermediate-depth seismic source with a spatial correlation model. The seismic risk evaluation method applied in this study is based on the well-known macroseismic method. For several structural typologies, the vulnerability parameters are evaluated based on a damage survey performed on 18,000 buildings in Bucharest after the March 1977 earthquake. Subsequently, the risk metrics are compared with those from other studies in the literature that apply a different risk assessment methodology in order to gain a better view of the uncertainties associated with a seismic risk study at city level. Finally, the impact of several Vrancea intermediate-depth earthquake scenarios is evaluated and the results show that the earthquake which has the closest epicenter to Bucharest appears to be the most damaging. 相似文献
6.
Seismic risk assessment of buildings in Izmir,Turkey 总被引：1，自引：1，他引：0
Izmir, the third largest city and a major economic center in Turkey, has more than three million residents and half million
buildings. In this study, the seismic risk in reinforced concrete buildings that dominate the building inventory in Izmir
is investigated through multiple approaches. Five typical reinforced concrete buildings were designed, modeled and assessed
for seismic vulnerability. The sample structures represent typical existing reinforced concrete hospital, school, public,
and residential buildings in Izmir. The seismic assessments of the considered structures indicate that they are vulnerable
to damage during expected future earthquakes. 相似文献
7.
Shafiee Ali Kamalian Mohsen Jafari Mohammad Kazem Hamzehloo Hossein 《Natural Hazards》2011,59(1):481-505
An important step in effectively reducing seismic risk and the vulnerability of a city located in an earthquake prone area
is to conduct a ground motion microzonation study for the desired return period. The International Institute of Earthquake
Engineering and Seismology (IIEES) initiated a number of seismic microzonation projects for Iran. This paper presents the
steps followed by IIEES in ground motion microzonation. IIEES performs both probabilistic and deterministic seismic hazard
analysis. IIEES uses his own fault map for seismotectonic studies and develops modulus and damping curves for the soils in
the study area. The experience of ground motion microzonation shows that in almost all cases, the estimated 475-year peak
ground acceleration (PGA) values are higher than the PGA proposed by the Iranian seismic code. Although ground motion microzonation
in Iran has some shortcomings, IIEES is making new improvement. This includes development in deterministic seismic hazard
analysis, two-dimensional and three-dimensional modelling of basin and topographical effects, using microtremor measurements
to find shear-wave velocity profiles in high-density urban areas and providing maps for spectral acceleration in the study
area. 相似文献
8.
Overview of Taiwan Earthquake Loss Estimation System 总被引：2，自引：1，他引：2
The National Science Council (NSC) of Taiwan started the HAZ-Taiwan project in 1998 to promote researches on seismic hazard
analysis, structural damage assessment, and socio-economic loss estimation. The associated application software, “Taiwan Earthquake
Loss Estimation System (TELES)”, integrates various inventory data and analysis modules to fulfill three objectives. First,
it helps to obtain reliable estimates of seismic hazards and losses soon after occurrence of large earthquakes. Second, it
helps to simulate earthquake scenarios and to provide useful estimates for local governments or public services to propose
their seismic disaster mitigation plans. Third, it helps to provide catastrophic risk management tools, such as proposing
the seismic insurance policy for residential buildings. This paper focuses on the development and application of analysis
modules used in early loss estimation system. These modules include assessments of ground motion intensity, soil liquefaction
potential, building damage and casualty. 相似文献
9.
Within the framework of recent research projects, basic tools for GIS-based seismic risk assessment technologies were developed and applied to the building stock and regional particularities of German earthquake regions. Two study areas are investigated, being comparable by the level of seismic hazard and the hazard-consistent scenario events (related to mean return periods of 475, 2475 and 10000 years). Significant differences exist with respect to the number of inhabitants, the grade and extent of urbanisation, the quality and quantity of building inventory: the case study of Schmölln in Eastern Thuringia seems to be representative for the majority of smaller towns in Germany, the case study of Cologne (Köln) stands for larger cities. Due to the similarities of hazard and scenario intensities, the considerable differences do not only require proper decisions concerning the appropriate methods and acceptable efforts, they enable conclusions about future research strategies and needs for disaster reduction management. Not least important, results can sharpen the focus of public interest. Seismic risk maps are prepared for different scenario intensities recognising the scatter and uncertainties of site-dependent ground motion and also of the applied vulnerability functions. The paper illustrates the impact of model assumptions and the step-wise refinements of input variables like site conditions, building stock or vulnerability functions on the distribution of expected building damage within the study areas. Furthermore, and in contrast to common research strategies, results support the conclusion that in the case of stronger earthquakes the damage will be of higher concentration within smaller cities like Schmölln due to the site-amplification potential and/or the increased vulnerability of the building stock. The extent of damage will be pronounced by the large number of masonry buildings for which lower vulnerability classes have to be assigned. Due to the effect of deep sedimentary layers and the composition of building types, the urban centre of Cologne will be less affected by an earthquake of comparable intensity. 相似文献
10.
11.
Balqis M. Rehan 《Natural Hazards》2018,91(3):1039-1057
Economic damage assessment for flood risk estimation is established in many countries, but attentions have been focused on macro- or meso-scale approaches and less on micro-scale approaches. Whilst the macro- or meso-scale approaches of flood damage assessment are suitable for regional- or national-oriented studies, micro-scale approaches are more suitable for cost–benefit analysis of engineered protection measures. Furthermore, there remains lack of systematic and automated approaches to estimate economic flood damage for multiple flood scenarios for the purpose of flood risk assessment. Studies on flood risk have also been driven by the assumption of stationary characteristic of flood hazard, hence the stationary-oriented vulnerability assessment. This study proposes a novel approach to assess vulnerability and flood risk and accounts for adaptability of the approach to nonstationary conditions of flood hazard. The approach is innovative in which an automated concurrent estimation of economic flood damage for a range of flood events on the basis of a micro-scale flood risk assessment is made possible. It accounts for the heterogeneous distribution of residential buildings of a community exposed to flood hazard. The feasibility of the methodology was tested using real historical flow records and spatial information of Teddington, London. Vulnerability curves and residual risk associated with a number of alternative extents of property-level protection adoptions are estimated by the application of the proposed methodology. It is found that the methodology has the capacity to provide valuable information on vulnerability and flood risk that can be integrated in a practical decision-making process for a reliable cost–benefit analysis of flood risk reduction options. 相似文献
12.
Losses resulting from winter storms contribute a significant part to the overall losses among all natural hazards in most
mid-latitude European countries. A realistic assessment of storm risk is therefore essential for prevention and coping measures.
The paper presents a framework for probabilistic storm risk assessment for residential buildings which is exemplarily performed
for Germany. Two different approaches are described, and results are presented. The hazard-based approach brings together
hazard, vulnerability and building assets to calculate risk curves for each community. The storm-based approach uses loss
information from past storm events to calculate statistical return periods of severe storms. As a result, a return period
of 83 years to the most severe storm series in 1990 is calculated. Average annual losses of €170 million to residential buildings
are calculated for all over Germany. The study demonstrates how the approaches complement each other and how validation is
performed. 相似文献
13.
Northern Algeria has experienced many destructive earthquakes throughout its history. The largest recent events occurred in El Asnam on October 10, 1980 (moment magnitude; Mw = 7.3), in Constantine on October 27, 1985 (surface-wave magnitude; Ms = 6.0), and in Zemmouri–Boumerdes on May 21, 2003 (Mw = 6.8). Because of the high population density and industrialization in these regions, the earthquakes had disastrous consequences and hence highlighted the vulnerability of Algeria to seismic events. To reduce seismic risk in Constantine, the capital city of East Algeria, we present a seismic risk scenario for this city, focusing on the vulnerability of the key historic areas of Coudia, Bellevue–Ciloc, and the Old City. This scenario allows us to assess the maximum ground acceleration using empirical attenuation laws, based on the following considerations: (a) the 1985 Constantine seismic event as an earthquake reference; (b) site effects related to regional geology; (c) damage to buildings, and (d) seismic vulnerability. This study shows the map of peak ground acceleration taking into account the effects of site lithology (Avib). We observe the strongest vibrations along the two rivers “Boumerzoug and Rhumel” and also, we note that the EC8 gives a good estimate acceleration in the image of the three studied areas (Bellevue–Ciloc, Coudia, and Old Town). By correlating with the geology, we observe an acceleration of 0.13 g in the neritic limestone of the rock (Old Town) something that fits with the value obtained 0.14 g (PGA) without taking into consideration the lithology. Moreover, according to the Algerian Earthquake Engineering Code (2003) (RPA), the Wilaya of Constantine is classified in the zone IIa (medium seismicity) with an acceleration data of 0.25 g. This study integrates geographic information system (GIS) data into risk models.
相似文献14.
Northern Algeria has experienced many destructive earthquakes throughout its history. The largest recent events occurred in El Asnam on October 10, 1980 (moment magnitude; Mw = 7.3), in Constantine on October 27, 1985 (surface-wave magnitude; Ms = 6.0), and in Zemmouri–Boumerdes on May 21, 2003 (Mw = 6.8). Because of the high population density and industrialization in these regions, the earthquakes had disastrous consequences and hence highlighted the vulnerability of Algeria to seismic events. To reduce seismic risk in Constantine, the capital city of East Algeria, we present a seismic risk scenario for this city, focusing on the vulnerability of the key historic areas of Coudia, Bellevue–Ciloc, and the Old City. This scenario allows us to assess the maximum ground acceleration using empirical attenuation laws, based on the following considerations: (a) the 1985 Constantine seismic event as an earthquake reference; (b) site effects related to regional geology; (c) damage to buildings, and (d) seismic vulnerability. This study shows the map of peak ground acceleration taking into account the effects of site lithology (Avib). We observe the strongest vibrations along the two rivers “Boumerzoug and Rhumel” and also, we note that the EC8 gives a good estimate acceleration in the image of the three studied areas (Bellevue–Ciloc, Coudia, and Old Town). By correlating with the geology, we observe an acceleration of 0.13 g in the neritic limestone of the rock (Old Town) something that fits with the value obtained 0.14 g (PGA) without taking into consideration the lithology. Moreover, according to the Algerian Earthquake Engineering Code (2003) (RPA), the Wilaya of Constantine is classified in the zone IIa (medium seismicity) with an acceleration data of 0.25 g. This study integrates geographic information system (GIS) data into risk models. 相似文献
15.
Dale Dominey-Howes Paula Dunbar Jesse Varner Maria Papathoma-Köhle 《Natural Hazards》2010,53(1):43-61
The Cascadia margin is capable of generating large magnitude seismic-tsunami. We use a 1:500 year tsunami hazard flood layer
produced during a probabilistic tsunami hazard assessment as the input to a pilot study of the vulnerability of residential and commercial buildings in Seaside, OR, USA. We map building
exposure, apply the Papathoma Tsunami Vulnerability Assessment Model to calculate building vulnerability and estimate probable maximum loss (PML) associated with a 1:500 year tsunami flood. Almost US$0.5 billion worth of buildings would be inundated, 95% of single
story residential and 23% of commercial buildings would be destroyed with PML’s exceeding US$0.5 billion worth of buildings would be inundated, 95% of single
story residential and 23% of commercial buildings would be destroyed with PML’s exceeding US116 million. These figures only
represent a tiny fraction of the total values of exposed assets and loss that would be associated with a Cascadia tsunami
impacting the NW Pacific coast. Not withstanding the various issues associated with our approach, this study represents the
first time that PML’s have ever been calculated for a Cascadia type tsunami, and these results have serious implications for
tsunami disaster risk management in the region. This method has the potential to be rolled out across the United States and
elsewhere for estimating building vulnerability and loss to tsunami. 相似文献
16.
Social vulnerability and seismic risk perception. Case study: the historic center of the Bucharest Municipality/Romania 总被引：3，自引：2，他引：1
Iuliana Armaş 《Natural Hazards》2008,47(3):397-410
Social vulnerability is as much a part of risk as building damage, hazard magnitude, and economic loss. Social vulnerability refers to the capacity of a human community exposed during the impact of a natural hazard event (in this case, an earthquake)
to resist, cope with, and recover from that impact. In the perspective of the 3rd millennium, we come to understand that the
most efficient and accessible way to reduce the pressure of natural risks is to reduce the vulnerability level of the human
communities exposed to that certain hazard. This study aims to test, in an exposed and vulnerable area, the relationship between
social vulnerability and the perception of the seismic risk. The research focuses only on the first level of social vulnerability,
defined as the ability of an individual within a household to recover from a natural hazard impact (Dwyer et al. 2004). A prevailing assumption was that social vulnerability influences the level of perception of the seismic risk, in an exposed, vulnerable area. To this end, two samples were used, different under the aspect of social vulnerability, in the context of the same residential
area. Social vulnerability was computed as a normalized composed index that includes the poverty ratio and the demographic
vulnerability ratio (depending on the age, gender, and education level indicators). The statistical processing has indicated
a significant difference in the high perception level for the two samples that were compared, in the sense that in the context
of an increased level of social vulnerability, people generally better acknowledge the seismic risk.
相似文献
| Iuliana ArmaşEmail: |
17.
Assessment of seismic vulnerability of urban areas provides fundamental information for activities of planning and management of emergencies. The main difficulty encountered when extending vulnerability evaluations to urban contexts is the definition of a framework of assessment appropriate for the specific characteristics of the site and providing reliable results with a reasonable duration of surveys and post-processing of data. The paper proposes a new procedure merging different typologies of information recognized on the territories investigated and for this reason called “hybrid.” Knowledge of historical events influencing urban evolution and analysis of recurrent building technologies are used to evaluate the vulnerability indexes of buildings and building stocks. On the other hand, a vulnerability model is calibrated by means of experimental and numerical investigations on prototype buildings representative of the most recurrent typologies. In the final framework, the vulnerability index, calculated through simplified assessment forms, is linked to the seismic intensity expressed by the peak ground acceleration and associated with an index of damage expressing the economical loss. The procedure has been tested on the urban center of Lampedusa island (Italy) providing as the output vulnerability index maps, vulnerability curves, critical PGA maps, and estimation of the economical damage associated with different earthquake scenarios. The application of the procedure can be suitably repeated for medium-to-small urban areas, typically recurring in the Mediterranean by carrying out each time a recalibration of the vulnerability model.
相似文献18.
Jairo A. Valcárcel Miguel G. Mora Omar D. Cardona Lluis G. Pujades Alex H. Barbat Gabriel A. Bernal 《Natural Hazards》2013,69(1):845-868
This article presents a methodology for an estimate of the benefit cost ratio of the seismic risk reduction in buildings portfolio at broadscale, for a world region, allowing comparing the results obtained for the countries belonging to that region. This methodology encompasses (1) the generation of a set of random seismic events and the evaluation of the spectral accelerations at the buildings location; (2) the estimation of the buildings built area, the economic value, as well as the classification in structural typologies; (3) the development of vulnerability curves for each typology; (4) the estimation of the annual average loss of the buildings portfolio in the current conditions as well as in the case of a hypothetical structural intervention. The benefit cost ratio is estimated as the difference between the estimates of the present value of these two annual average losses, divided by the retrofitting costs. This methodology has been applied to the portfolio of public schools of 14 countries of Latin America and the Caribbean, for evaluating the feasibility of the seismic risk reduction at a national scale. 相似文献
19.
Assessment of seismic vulnerability of urban areas provides fundamental information for activities of planning and management of emergencies. The main difficulty encountered when extending vulnerability evaluations to urban contexts is the definition of a framework of assessment appropriate for the specific characteristics of the site and providing reliable results with a reasonable duration of surveys and post-processing of data. The paper proposes a new procedure merging different typologies of information recognized on the territories investigated and for this reason called “hybrid.” Knowledge of historical events influencing urban evolution and analysis of recurrent building technologies are used to evaluate the vulnerability indexes of buildings and building stocks. On the other hand, a vulnerability model is calibrated by means of experimental and numerical investigations on prototype buildings representative of the most recurrent typologies. In the final framework, the vulnerability index, calculated through simplified assessment forms, is linked to the seismic intensity expressed by the peak ground acceleration and associated with an index of damage expressing the economical loss. The procedure has been tested on the urban center of Lampedusa island (Italy) providing as the output vulnerability index maps, vulnerability curves, critical PGA maps, and estimation of the economical damage associated with different earthquake scenarios. The application of the procedure can be suitably repeated for medium-to-small urban areas, typically recurring in the Mediterranean by carrying out each time a recalibration of the vulnerability model. 相似文献
20.
Seismic hazard maps are constructed by extrapolating from the frequency of small earthquakes, the annual probability of large, infrequent, earthquakes. Combining the potential contribution from all seismically active volumes, one calculates the peak ground acceleration with a probability to be exceeded by 10?% in 50?years at any given point. The consequential risk, the losses to be expected, derives from the damage the calculated shaking causes to buildings, and the impact on occupants due to collapsing structures. We show that the numbers of fatalities in recent disastrous earthquakes were underestimated by the world seismic hazard maps by approximately two to three orders of magnitude. Thus, seismic hazard maps based on the standard method cannot be used to estimate the risk to which the population is exposed due to large earthquakes. 相似文献