Seismic Hazard and Public Safety (original) (raw)

Reducing seismic risk by understanding its cultural roots

2013

The paper discusses how to approach the problem of the social mitigation of seismic risk, in order to reduce damage and grief consequent to earthquakes. An alert protocol, intended as a working hypothesis, is proposed based on the experience gained from analysis of the behaviour and social response to the threat before and after the great disaster of the L'Aquila earthquake on 6th April 2009. Authors propose a protocol addressing four levels of increasing alert based on signs of earthquake preparation and social concerns. In this sense, it works as an intensity scale and does not strictly relate to earthquake size (magnitude) or seismic hazard. The proposed alert protocol provides sensible measures for reducing vulnerability, which is the only factor that can be more or less efficiently controlled, based on structural and behavioural adjustments. Factors indicating the difficult relationship between politicians, scientific community and citizens are considered: 1) a serious gap between researchers and citizens; 2) measures adopted by local administrators and the National Civil Protection Service not agreed by the population; 3) misunderstanding originated from a lack of clarity of communication about scientific terminology; and 4) the lack of an alert procedure protocol. In the current situation, all these problems are crucial and contribute to the unpreparedness to face a seismic event, and thus greatly increase the risk. The adoption and implementation of an alert procedure protocol requires a preliminary assessment of the context and should be adapted to the local sensibility and culture. The application of a protocol may reduce the contrasts between preventive measures and individual responsibilities, making mitigation measures more feasible and socially acceptable. In this paper, risk evaluation is not strictly related to probabilistic or deterministic predictions. In fact, this is a result of a project that comes from the general analysis of risk and is not intended to give an alternative hazard estimate method. This paper proposes an alert protocol addressing four levels of increasing alert based on signs of earthquake generating preparation and social concerns. Finally, there is a suggestion on how to gradually communicate the threat and get citizens involved in the risk mitigation process.

School Seismic Safety and Risk Mitigation

Encyclopedia of Earthquake Engineering, 2015

Marla Petal*, Ben Wisner, Ilan Kelman, David Alexander, Omar-Dario Cardona, Djillali Benouar, Sanjaya Bhatia, Jitendra Kumar Bothara, Amod Mani Dixit, Rebekah Green, Ram Chandra Kandel, Tracy Monk, Bishnu Pandey, Janise Rodgers, Zeynep T€urkmen Sanduvac and Rajib Shaw Risk RED (Risk Reduction Education for Disasters), Los Angeles, USA Oberlin, OH, USA Institute for Risk and Disaster Reduction and Institute for Global Health, University College London, London, England University College London, London, England Universidad Nacional de Colombia, Manizales, Colombia University of Bab Ezzouar, Algiers, Algeria UNISDR Recovery Platform, Kobe, Japan NSET, Kathmandu, Nepal Miyamoto Impact, Christchurch, New Zealand University of Western Washington, Bellingham, USA Toronto, Canada Families for School Seismic Safety, Vancouver, Canada University of British Columbia, Vancouver, Canada GeoHazards International, Menlo Park, USA Risk RED, Istanbul, Turkey University of Kyoto, Kyoto, Japan

Recent Developments in Earthquake Hazards Studies

In recent years, there has been great progress understanding the underlying causes of earthquakes, as well as forecasting their occurrence and preparing communities for their damaging effects. Plate tectonic theory explains the occurrence of earthquakes at discrete plate boundaries, such as subduction zones and transform faults, but diffuse plate boundaries are also common. Seismic hazards are distributed over a broad region within diffuse plate boundaries. Intraplate earthquakes occur in otherwise stable crust located far away from any plate boundary, and can cause great loss of life and property. These earthquakes cannot be explained by classical plate tectonics, and as such, are a topic of great scientific debate. Earthquake hazards are determined by a number of factors, among which the earthquake magnitude is only one factor. Other critical factors include population density, the potential for secondary hazards, such as fire, landslides and tsunamis, and the vulnerability of man-made structures to severe strong ground motion. In order to reduce earthquake hazards, engineers and scientists are taking advantage of new technologies to advance the fields of earthquake forecasting and mitigation. Seismicity is effectively monitored in many regions with regional networks, and world seismicity is monitored by the Global Seismic Network that consists of more than 150 high-quality, broadband seismic stations using satellite telemetry systems. Global Positioning Satellite (GPS) systems monitor crustal strain in tectonically active and intraplate regions. A relatively recent technology, Interferometric Synthetic Aperture Radar (InSAR) uses radar waves emitted from satellites to map the Earth’s surface at high (sub-cm) resolution. InSAR technology opens the door to continuous monitoring of crustal deformation within active plate boundaries. The U.S. Geological Survey (USGS), along with other partners, has created ShakeMap, an online notification system that provides near-real-time post-earthquake maps of ground shaking intensity. These maps are especially useful for the coordination of emergency response teams and for the improvement of building codes. Using a combination of these new technologies, with paleoseismology studies, we have steadily improved the science of earthquake forecasting whereby one estimates the probability that an earthquake will occur during a specified time interval. A very recent development is Earthquake Early Warning, a system that will provide earthquake information within seconds of the initial rupture of a fault. These systems will give the public some tens of seconds to prepare for imminent earthquake strong ground motion. Advances in earthquake science hold the promise of diminishing earthquake hazards on a global scale despite ever-increasing population growth.

Evaluation of earthquake Hazard

2007

Introduction: Seismic Hazard Objective The general theme of this course is earthquake risk. The concept of risk includes hazard and vulnerability. The first part has dealt with earthquakes, where when they occur, how big they are and why they happen. The second part is about the effects. Hazard assessment is to evaluate, for a certain place, how frequent and how strong earthquake will be felt, in order to take measure to reduce the possible damages. In other terms, it is to qualify and quantify the level of ground motion in a site due to the earthquake. Seismic hazard maps depict the levels of chosen ground motions that likely will, or will not, be exceeded in specified exposure times. The ground motion can be the intensity of the earthquake, displacement, velocity or acceleration of the seismic wave at the site. Seismic hazard is determined by the following three factors: ● The distribution in time, space and size of the regional seismicity ● The attenuation of seismic waves at inc...

Reducing seismic risk by understanding its cultural roots: Inference from an Italian case history

The paper discusses how to approach the problem of the social mitigation of seismic risk, in order to reduce damage and grief consequent to earthquakes. An alert protocol, intended as a working hypothesis, is proposed based on the experience gained from analysis of the be- haviour and social response to the threat before and after the great disaster of the L’Aquila earth- quake on 6th April 2009. Authors propose a protocol addressing four levels of increasing alert based on signs of earthquake preparation and social concerns. In this sense, it works as an intensity scale and does not strictly relate to earthquake size (magnitude) or seismic hazard. The proposed alert protocol provides sensible measures for reducing vulnerability, which is the only factor that can be more or less efficiently controlled, based on structural and behavioural adjustments. Factors indicating the difficult re- lationship between politicians, scientific com- munity and citizens are considered: 1) a serious gap between researchers and citizens; 2) meas- ures adopted by local administrators and the National Civil Protection Service not agreed by the population; 3) misunderstanding originated from a lack of clarity of communication about scientific terminology; and 4) the lack of an alert procedure protocol. In the current situation, all these problems are crucial and contribute to the unpreparedness to face a seismic event, and thus greatly increase the risk. The adoption and implementation of an alert procedure protocol requires a preliminary assessment of the con- text and should be adapted to the local sensibil- ity and culture. The application of a protocol may reduce the contrasts between preventive measures and individual responsibilities, mak- ing mitigation measures more feasible and so- cially acceptable. In this paper, risk evaluation is not strictly related to probabilistic or determi- nistic predictions. In fact, this is a result of a project that comes from the general analysis of risk and is not intended to give an alternative hazard estimate method. This paper proposes an alert protocol addressing four levels of in- creasing alert based on signs of earthquake generating preparation and social concerns. Finally, there is a suggestion on how to gradu- ally communicate the threat and get citizens in- volved in the risk mitigation process.

INTEGRATED SEISMIC RISK MANAGEMENT – THE DIFFERENCE BETWEEN THE CODES AND THE REAL LIFE PRACTICE

Earthquake Engineering emerged during the time from 1910 to 1930's, resulting with first building codes which included earthquake activities as loads. Seismic engineering need was triggered by devastating earthquakes in Northern California, and Messina -Italy. Since then, and especially during the last decades, earthquake engineering has increasingly advanced ever changing the norms and building codes. By now the preventive measures of earthquake risk mitigation have drastically evolved suggesting protection not only for new buildings, but also for the existing ones which make the majority of our surrounding built world.

Seismic hazard for critical facilities

Critical facilities are man-made equipments, plants, constructions, and structures that, if affected by a strong earthquake, can produce serious impacts on people, environment, design are required and detailed seismic hazard evaluations have to be developed. In on the seismic hazard of nuclear power plants is presented since this type of critical facilities could be considered the facilities that more than others have contributed to

EARTHQUAKES AND PREVENTIVE MEASURES

The most important natural hazard in Greece is earthquake. The earthquake phenomenon can be explained using the theory of Plate Tectonics. Greece lies in the middle of the collision between two major tectonic plates, the Eurasian and the African, resulting in a very fragmented geotectonic regime. From the point of energy released, half of the European seismic energy is released within the Greek territory. Thus, the ways and means of reducing the seismic risk, that is the consequences from an earthquake, is for Greece of vital importance. The seismic risk is the convolution of the seismic hazard and the vulnerability of the specific area. From those factors, the vulnerability, which expresses the weakness or the sensitivity of the system and the value at risk during an earthquake, is the only parameter that can and should be minimized. 's, (E.P.P.O.), main target is to plan the national policy for earthquake protection, as well as to coordinate the public and private resources for the implementation of this policy, through issuing regulations, guidelines for emergency situation or for strengthening existing buildings including monuments of cultural heritage value e.t.c. EPPO also has a strong educational/training focus, targeting inter alia schools and hospitals. Of importance are also bottom up approaches, often at the personal level, which include useful measures concerning the proper behaviour before, during and after a destructive earthquake. These approaches are also part of the EPPO mandate and focus.