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3 Elements of the Roadmap
Pages 51-170

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From page 51...
... Also, some activities are scalable, that is, they can be conducted at varying levels of effort or units. At the outset of its work, the committee was briefed on the NEHRP Strategic Plan and subsequently reviewed the plan, with supporting documents, in detail.
From page 52...
... Earthquake Early Warning 4. National Seismic Hazard Model 5.
From page 53...
... The hazard posed by the southernmost segment of the San Andreas Fault is recognized to be high, for example -- more than 300 years have passed since its last major earthquake, which is longer than a typical interseismic interval on this particular fault. Physics-based numerical simulations show that, if the fault ruptures from the southeast to the northwest -- toward Los Angeles -- the ground motions in the city will be larger and of longer duration, and the damage will be much worse, than if the rupture propagates in the other direction (Figure 3.1)
From page 54...
... Improve the accuracy, timeliness, and content of earthquake information products √ 10. Develop comprehensive earthquake risk scenarios and risk assessments 11.
From page 55...
... National Seismic √ √ √ √ √ √ Hazard Model 5. Operational Earthquake √ √ √ √ √ Forecasting 6.
From page 56...
... Develop comprehensive earthquake risk scenarios and risk assessments 11. Support development of seismic standards and building codes and advocate their adoption and enforcement 12.
From page 57...
... Earthquake Resilient Community √ √ √ √ √ √ √ √ √ and Regional Demonstration Projects 57
From page 58...
... The right panel shows faulting that begins at the northwest end and ruptures to the southeast. The ground motions predicted in the Los Angeles region are much more intense and have longer duration in the former case.
From page 59...
... • Earthquake rupture dynamics: how forces produce fault ruptures and generate seismic waves during an earthquake. The nucleation, propagation, and arrest of fault ruptures depend on the stress response of rocks approaching and participating in failure.
From page 60...
... Current forecasts, such as those used in all three iterations of the National Seismic Hazard Maps (Frankel et al., 1996, 2002; Petersen et al., 2008) , are time-independent; i.e., they assume earthquakes occur randomly in time and are independent of past seismic activity.
From page 61...
... , will require a better understanding of how earthquake probabilities depend on the quasi-static stress transfer caused by permanent fault slip and related relaxation of the crust and mantle, as well as the dynamic stress triggering caused by the passage of seismic waves. Many of the potential advances in earthquake forecasting, seismic hazard characterization, and dissemination of post-earthquake information will depend on harnessing the predictive power of earthquake physics.
From page 62...
... . And more accurate earthquake simulations can provide a physical basis for developing comprehensive earthquake risk scenarios and risk assessments (Objective 10)
From page 63...
... Investigations of the first problem began with attempts to place earthquake occurrence in a global framework and contributed to the discovery of plate tectonics, while work on the second addressed the needs of earthquake engineering and led to the development of seismic hazard analysis. The historical separation between these two lines of inquiry has been narrowed by progress on dynamical models of earthquake occurrence, fault ruptures, and strong ground motions.
From page 64...
... and, working with engineers, how to predict the site-specific response of buildings, lifelines, and critical facilities to seismic excitation. The longterm expectations for potentially destructive shaking have been quanti fied in the form of seismic hazard maps, which display estimates of the maximum shaking intensities expected at each locality in the United States (see Figure 3.8 under Task 4)
From page 65...
... For example, airborne LiDAR mapping has been used to reduce by 40% the slip along the Carrizo section of the San Andreas Fault previously ascribed to the 1857 Fort Tejon earthquake (magnitude-7.9) , implying a higher medium-term probability that another large earthquake will occur on this section of the fault (Zielke et al., 2010)
From page 66...
... Taken from end to end, the problem comprises the loading and eventual failure of tectonic faults, the generation and propagation of seismic waves, the response of surface sites, and -- in its application to seismic risk -- the damage caused by earthquakes to the built environment (see Task 12)
From page 67...
... An additional implementation issue, of course, is the need for information from major earthquakes that can only be provided by the monitoring systems described in Task 2. TASK 2: ADVANCED NATIONAL SEISMIC SYSTEM Seismic monitoring is vital for meeting the nation's needs for timely and accurate information about earthquakes, tsunamis, and volcanic eruptions -- information to determine their locations and magnitudes and estimate their potential effects.
From page 68...
... . By that time, ANSS will consist of more than 1,500 modern digital seismic stations, upgraded regional seismic networks, and a National Earthquake Information Center that is operated 24×7 and delivers information for emergency response to state and local officials, operators of lifeline facilities, the Federal Emergency Management Agency (FEMA)
From page 69...
... SOURCE: Courtesy of the USGS Earthquake Hazards Program. Figure 3.4.eps landscape 3 bitmaps with vector type & plotted points (1 bitmap consists of wedges)
From page 70...
... • Hazard Maps. National Seismic Hazard Maps show earthquake ground motions for various probability levels across the United States, for application in the seismic provisions of building codes, insurance rate structures, risk assessments, and other public policy uses (see Task 4)
From page 71...
... The goal of network-based EEW is to detect earthquakes in the early stages of fault rupture, rapidly predict the intensity of the future ground motions, and warn people before they experience the intense shaking that might cause damage. The most damaging shaking is usually caused by seismic shear and surface waves, which travel at only half the speed of the fast est seismic waves, and much slower than an electronic warning message.
From page 72...
... In this scenario, an EEW system deployed along the southern San Andreas Fault could provide up to a minute of warning at sites in the most urbanized regions of Los Angeles. This particular earthquake simulation was used to define the hazard for the 2008 Great Southern California ShakeOut.
From page 73...
... Japan is the only country with a nationwide system that provides public alerts. The Japan Meteorological Agency uses a national seismic network of about 1,000 seismological stations to detect earthquakes and issue warnings, which are transmitted via the Internet, satellite, and wireless networks to cell phone users, to desktop computers, and to automated control systems that stop trains, place sensitive equipment in a safe mode, and isolate hazards while the public takes cover (Figure 3.6)
From page 74...
... 74 NATIONAL EARTHQUAKE RESILIENCE FIGURE 3.6 Portion of a leaflet prepared by the Japan Meteorological Agency Figure 3.6.eps describing simple instructions on how to react when an EEW alert is received. bitmap SOURCE: Japan Meteorological Agency.
From page 75...
... The enhancements could be based on existing dense urban seismic networks with directed annunciation of the warning to the exposed individuals, or on fully mobile aftershock monitoring networks that can be rapidly installed in sparsely monitored locales. Current EEW systems are based on earthquake detection and forecasting by seismometer networks such as the CISN.
From page 76...
... employs a network of 1,000 seismic instruments to detect earthquakes and predict the intensity of the resulting ground motions. Warnings are sent via TV and radio and go out over public address systems in schools, some shopping malls, and train stations.
From page 77...
... Physics-based numerical simulations of strong ground motions have the potential for substantially improving these predictions (see Tasks 1 and 12)
From page 78...
... will be useful in this regard. TASK 4: NATIONAL SEISMIC HAZARD MODEL The National Seismic Hazard Maps produced by USGS are the authoritative reference for earthquake ground motion hazard in the United States.
From page 79...
... Existing Knowledge and Current Capabilities The current knowledge of earthquakes, active faults, crustal deforma tion and seismic wave generation/propagation must be integrated and translated into a form that can be used by others in order to be effective in reducing earthquake losses. The National Seismic Hazard Maps and related information products produced by USGS accomplish this critical information transfer.
From page 80...
... bitmap FIGURE 3.8 U.S. National Seismic Hazard Map showing Peak Ground Acceleration (PGA)
From page 81...
... Site and soil conditions vary geographi cally, and regional or local seismic hazard maps are needed to provide a higher spatial resolution to account for these differences and more accu rately estimate strong ground motion effects. A number of successful pilot programs around the United States have demonstrated the value the NEHRP Urban Seismic Hazards Mapping Program.
From page 82...
... Available at seattlepi.com/U.S.G.S. Seismic hazard maps for Seattle, replacement 3-9 WA, were improved following the magnitude-6.7 Nisqually, WA, earthquake in 2001.
From page 83...
... A new series of earthquake risk maps combine hazard information from the National Seismic Hazard Maps with building fragility curves from FEMA's HAZUS-Multi-Hazard earthquake loss estimation model to show mean annual frequencies of exceeding different structural damage states (Luco and Karaca, 2007)
From page 84...
... can advance understanding of earthquake effects to the built environment and help reduce uncertainties in areas of infrequent seismicity. Significant improvements to the empirical attenuation rela tions may be possible through the use of numerical simulations of ground motions that incorporate realistic models of source dynamics and threedimensional geological structure (see Figure 3.1)
From page 85...
... , surface fault rupture, and landslide potential is needed to complement the maps already available for ground shaking. Although the adoption of the USGS National Seismic Hazard Maps into the model building codes is a major NEHRP success story, the actual implementation and enforcement of these codes remains a community choice.
From page 86...
... Authoritative statements about the increase in seismic hazard following a significant earthquake allow emergency management agencies, as well as the population at large, to anticipate aftershocks. Such advisories also fulfill the public's need for current information during periods of anomalous seismic activity, which can help to reduce the con cern about amateur predictions and rumors that overly inflate the hazard.
From page 87...
... Earthquake forecasting procedures should be qualified for usage according to the three criteria commonly applied in weather forecasting (Jordan and Jones, 2010) : they should display quality, a good correspondence between the forecasts and actual earthquake behavior; consistency, compatibility among procedures used at different spatial or temporal scales; and value, realizable benefits (relative to costs incurred)
From page 88...
... . The implementation of operational earthquake forecasting will enable cost-effective measures to reduce earthquake impacts on individuals, the built environment, and society-at-large -- Goal B in NIST (2008)
From page 89...
... Long-term forecasts provide probabilistic estimates of where earthquakes will occur, how large they might be, and how often they will happen, averaged over time intervals of decades to centuries. This information is essential for seismic hazard mapping, and it is the foundation on which the operational earthquake forecasting is built (see Task 4)
From page 90...
... For instance, beginning on the morning after the damaging L'Aquila earthquake of April 6, 2009, the Italian authorities began to post 24-hour forecasts of aftershock activity. An operational system is the Short-Term Earthquake Probability (STEP)
From page 91...
... 91 ELEMENTS OF THE ROADMAP FIGURE 3.11 Short Term Earthquake Probability (STEP)
From page 92...
... . STEP uses aftershock statistics to make hourly revisions of the probabilities of strong ground motions (Modified Mercalli Intensity ≥ VI)
From page 93...
... However, from an operational perspective, forecasting value can be better represented in terms of the strong ground motions that constitute the primary seismic hazard. This approach has been applied in the STEP model, which forecasts ground motion exceedance probabilities at a fixed shaking intensity, and it should be considered in the future formulation and testing of operational models.
From page 94...
... provide technical information to assist with scenario development. Over the next 20 years, NEHRP should continue to update this information by incorporating the latest developments in both the National and Urban Seismic Hazard and Risk Maps.
From page 95...
... 95 ELEMENTS OF THE ROADMAP TABLE 3.2 HAZUS-MH Annualized Earthquake Loss (AEL) and Annualized Earthquake Loss Ratios (AELR)
From page 96...
... Not only can such scenarios stimulate new policies and programs, but also the process of scenario development itself often results in greater understanding and improved trust and communication between members of the scientific, engineering, emergency management, and policy communities, resulting in a "new community" dedicated to seismic risk reduction.12 Earthquake scenarios have been developed for a number of fault zones in the United States, and are available from the EERI Developing Earthquake Scenarios website.13 The earthquake scenarios that have been developed for California include the Hayward and San Andreas Faults in 8 See www.fema.gov/plan/prevent/hazus/hz_cdms2.shtm. 9 See www.shakeout.org/.
From page 97...
... worked with Oregon Emergency Management and the University of Oregon to develop countywide earthquake and landslide hazard maps as well as earthquake damage and loss estimates as part of its natural hazard mitigation plans. Based on improved information, one Cascadia earthquake scenario estimates more than $11 billion in building damages for the mid- and southern Willamette Valley (Burns et al., 2008)
From page 98...
... 98 NATIONAL EARTHQUAKE RESILIENCE FIGURE 3.12 The Seattle Fault Scenario, depicting the impact of a magnitude-6.7 earthquake on the Seattle Fault. Figure 3.12.epsal.
From page 99...
... Enabling Requirements Scientifically credible earthquake scenarios and ground motions are based on NEHRP products such as the National Seismic Hazard Maps and ShakeMaps. Disaggregation of the national hazard maps to produce scenario ground motion maps allows communities to examine the local seismic hazard from individual earthquakes.
From page 100...
... TASK 7: EARTHQUAKE RISK ASSESSMENTS AND APPLICATIONS While national seismic hazard maps and earthquake scenarios contribute to understanding earthquake hazards, there is an increased recognition among policy-makers, researchers, and practitioners of the need to ana lyze and map earthquake risk in the United States. As urban development continues in earthquake-prone regions, there is a growing concern about the exposure of buildings, lifelines, and people to the potential effects of destructive earthquakes.
From page 101...
... Continued improvements to earthquake risk and loss estimation methodologies and the development of community risk models are two activities that have been identified as NEHRP focus areas: 1. Promote the continued development and enhancement of earth quake risk assessment and loss estimation methodologies and databases.
From page 102...
... • New information and data (i.e., new attenuation models, building fragility curves, demographics, lifeline performance models, network interdependencies, indirect economic losses)
From page 103...
... , and include those developed by AIR Worldwide, EQECAT, Risk Management Solutions, and URS. In addition to these proprietary earthquake loss estimation programs, there are currently two publicly available loss estimation or risk assessment programs -- FEMA's HAZUS, and the Mid-America Earthquake Center's MAEviz program: • FEMA developed HAZUS in cooperation with the National Institute of Building Sciences (NIBS)
From page 104...
... These types of retrospective loss avoidance studies show how future losses can be recognized and avoided through simulation modeling and proactive community mitigation programs. Loss estimates are affected by uncertainty -- uncertainty in estimating the likelihood and intensity of strong ground motion, uncertainty in actual community building and infrastructure inventories, uncertainty concern ing the levels of damage to the built environment, and uncertainty in the social and economic losses associated with the predicted damage.
From page 105...
... . Enabling Requirements To continue the progress already made in community earthquake risk assessment, continued NEHRP-funding for the development of nationally consistent datasets -- such as the National and Urban Seismic Hazard Maps discussed in Tasks 4 and 6, and improved fragility curves for model building types that account for regional differences in construction prac tices, code levels, and structural condition -- is essential.
From page 106...
... Mapping local geology in three dimensions and incorporating more detailed grids into maps of site response, liquefaction, and landslide potential increase the granularity of these data, which then improve the resolution of the community earthquake risk assessments. Implementation Issues Open- Versus Closed-Source Software In addition to informing risk assessment and mitigation activities, the HAZUS loss estimation software -- which is "closed-source" software (i.e., the source code is not available to the community)
From page 107...
... The more important research questions have become how and why communities and regions are able to leverage expected (and perhaps planned) and improvised emergency response and recovery activities in both the public and private sectors.
From page 108...
... and improvised emergency response and recovery activities and outcomes at community and regional levels, as they are supported in varying degrees by the federal government. The primary research targets on emergency response and recovery activities are governmental, medical, and educational organizations, social services agencies, public utilities, and industrial and commercial organizations.
From page 109...
... . Accordingly, the proposed research has three primary aims: first, to build on existing knowledge of emergency response and related preparedness practices; second, to expand knowledge about disaster recovery and related preparedness practices; and third, to develop models and decision support tools that are increasingly grounded in social science knowledge about disaster response and recovery.
From page 110...
... An important difference between emergency response and recovery is that the key players in the former (e.g., police, fire, emergency medical services, public utilities, local emergency management offices) and the latter (e.g., community development agencies, land-use boards, real estate companies, banks, insurance companies, local businesses)
From page 111...
... With that cooperation, sample frames of those engaged in emergency response and recovery activities can be pre-determined to a much larger extent than has been possible in the past. Standardized data protocols on expected and improvised activities and their determinants can be developed and made ready on a standby basis.
From page 112...
... . Technologies that enable data archiving, data mining, and data dissemination must be augmented in the immediate future by formal management of data sharing.
From page 113...
... . Implementation Issues Three central implementation issues, and their possible resolution, merit serious consideration: lack of predictability about when large-scale earthquakes and other major disasters will occur; current lack of standardized research protocols on post-disaster response and recovery activities and related pre-disaster preparedness practices; and lack of standby research facilities and capabilities to implement standardized research protocols and manage data resulting from their use.
From page 114...
... Capturing, distilling, and disseminating lessons about the geological, structural, institutional, and socioeconomic impacts of earthquakes, as well as the responses post-disaster, are critical require ments for advancing knowledge and more effectively reducing earthquake losses. The 2008 NEHRP Strategic Plan for 2006-2010 identifies the creation and maintenance of a repository of important post-earthquake reconnais sance data as a strategic priority to improve understanding of earthquake processes and impacts (NEHRP, 2007)
From page 115...
... The system, in itself, will be a significant engineering effort, and it will also require sustained multi-year funding to implement and maintain in order to cost-effectively preserve data over time, so it will still be accessible and usable for future infrastructure design, and for mitigation and disaster management efforts. It will help ensure that NEHRP's mission -- to develop, disseminate and promote knowledge, tools, and practices for earthquake risk reduction in the pre-disaster environment -- can also be successful in the post-disaster environment.
From page 116...
... community and possible opportunities for cooperation and collaboration in addressing those needs. The findings from the workshop contributed to the identification of "Improve postearthquake information acquisition and management" as an objective and "Develop a national post-earthquake information management system" as a strategic priority in the 2008 NEHRP Strategic Plan (NIST, 2008)
From page 117...
... System requirements and system-level issues have been identified that relate to data collection, organization, and storage; data curation and quality assurance; information presentation, discovery, and retrieval; privacy and security; and long-term data preservation. Implementation Issues PIMS is similar to NSF's national environmental observatory efforts, and the overall timescale from project initiation to mature operational capability is 5 to 10 years; however, it could occur in two phases (PIMS Project Team, 2008)
From page 118...
... . Long-term recovery needs time to be accomplished thoughtfully and to allow for proper deliberation and public discourse on how to achieve risk reduction and betterments.
From page 119...
... Task 8 complements this section by addressing emergency response and related short-term recovery. Task 11 recommends the creation of an Observatory Network that would help promote these goals in part, espe cially with respect to on-going data collection and analysis.
From page 120...
... Predictive models of individual and community resilience are also valuable. Some initial attempts, analogous to Cutter's design of a vulnerability index (Cutter et al., 2003)
From page 121...
... . The extent to which business interruption losses can be reduced.
From page 122...
... Many advances are continuing at the Earthquake Engineering Research Centers, but more fresh approaches are needed (e.g., Grubesic et al., 2008)
From page 123...
... 123 ELEMENTS OF THE ROADMAP urban landscape to avoid duplication, establish consistency, and capitalize on synergies. • Exploration of equity and justice considerations.
From page 124...
... incurring business interruption losses and waiting until prices settle down in order to reduce recovered costs. Theoretical and empirical analyses are needed to better understand this phenomenon and to be able to predict its course.
From page 125...
... . But, recovery needs time to be accomplished thoughtfully and to allow for proper deliberation and public discourse on how to achieve risk reduction and betterments; and, recovery managers are often pressured to go faster than information, knowledge, and planning generally flows.
From page 126...
... . In effect, several integrated assessment models of earthquake risk, vulnerability, and consequences (e.g., HAZUS)
From page 127...
... Although HAZUS (FEMA, 2008) represents a major milestone in making it possible for many analysts to undertake hazard loss estimation, it is not without its limitations.
From page 128...
... More extensive analysis is needed to determine the extent to which the ensuing results are overly sensitive to the parameter's changes and limitations of the user's abilities. Although HAZUS serves as a useful tool for loss estimation, it is necessarily simplified to render it accessible to a broad range of users, as it is intended to be accessible at every emergency planning office in the United States.
From page 129...
... It is not a requirement that the federal government design, fund, direct, and implement all resilience activities; rather, stronger working relationships and enlightened multi-level governance will further promote resilience in practice. TASK 11: OBSERVATORY NETWORK ON COMMUNITY RESILIENCE AND VULNERABILITY The research community has, on numerous occasions, identified key data collection obstacles that are impeding the advancement of knowledge regarding earthquakes and other disasters, their impacts on society, and factors influencing communities' disaster risk and resilience (see also Task 8)
From page 130...
... This observatory network would focus on the dynamics of social systems and the natural and built environments with which they are linked. The network would facilitate efficient collection, sharing, and use of data on disaster events and disaster-prone communities.
From page 131...
... Thus it is imperative for the research community to develop and utilize standardized, common data collection protocols and instruments, and to share the data acquired in a shared repository. Knowledge regarding risk assessment, risk perception, and manage ment strategies is also fundamental to advancing national earthquake resilience.
From page 132...
... These limitations -- lack of longitudinal perspectives, small samples of communities, and partial rather than holistic explana tions of risk-related behaviors -- remain important knowledge gaps. Pre-disaster mitigation activities -- including addressing seismic risk through building codes, structural and nonstructural retrofits, and landuse planning -- represent the primary means through which earthquake losses can be reduced in the long term.
From page 133...
... . Focusing on data for 1993 to 2003, this landmark study found that FEMA's natural hazard mitigation grant programs were costeffective and resulted in considerable net benefits in the form of reduced future losses from natural disasters.
From page 134...
... A national observatory network is needed to address the disaster vulnerability and resilience of human communities (e.g., cities) , using methodologies applied consistently over time and space, with attention to the complex, place-based interactions between changes in social systems, the built environment, and the natural environment.
From page 135...
... . The scope of the Observatory Network should be multi-hazard, including but not be exclusively focused on earthquake hazard.
From page 136...
... The Observatory Network should therefore be structured to foster data sharing, comparative study, and policy analysis across hazards. Implementation Issues Implementation of a distributed network is likely to require a multiyear, phased process.
From page 137...
... Proposed Actions ➣ Advance the practice of engineering design practice across all disciplines through the development and implementation of validated multi-scale models of materials, components, and elements of the built environment, and the use of high-performance computing and data visualization. ➣ Maximize the impact on national earthquake resilience by integrating knowledge gained in Tasks 1, 13, 14, and 16 and "operationalizing" the integrated product using end-to-end simulation.
From page 138...
... computations are typically performed using empirical macro models of structural components assembled into a numerical model of the facility/lifeline and spectrumcompatible earthquake ground motions input to the numerical model at the ground surface. Nonstructural components and assemblies are treated as cascading systems.
From page 139...
... A comprehensive research program is needed to better characterize earthquake sources and the strong ground motions they produce, as described under Task 1. • Facilities or lifelines are often constructed on a 3D heterogeneous soil basin of varying depth and breadth.
From page 140...
... NSF and USGS should develop analysis and visualization tools to process large volumes of data and enable decisionmaking in a timely manner. Implementation Issues Physics-based simulations describing the response of the built envi ronment to fault rupture have been deployed on a limited basis (Olsen et al., 2009; Graves et al., 2010)
From page 141...
... Proposed Actions ➣ Conduct integrated laboratory research and numerical simulations to substantially increase understanding of the nonlinear response of archaic materials, structural components, and framing systems. ➣ Develop reliable, practical analytical methods that predict the response of existing buildings with known levels of reliability.
From page 142...
... Existing Knowledge and Current Capabilities The issue of seismic risk from existing buildings was put on a national stage when FEMA launched its Program to Reduce the Seismic Hazards of Existing Buildings. The Action Plan describing the main elements of that program was developed at a workshop held in Tempe, AZ, in 1985 (FEMA, 1985a, 1985b)
From page 143...
... , but more complete training of engineers and other stakeholders about the entire retrofit process will be required to accomplish significant reduction of risk from existing buildings, particularly in regions with risks less clear than from the known faults on the West Coast. Enabling Requirements Many of the basic knowledge needs and implementation tools required to improve this significant mitigation activity are similar to those needed to advance performance-based earthquake engineering.
From page 144...
... • Collect, curate, and archive building inventory data in all seismic regions to facilitate regional loss estimation and to focus research on the most common high-risk building and structural types. • Calibrate evaluation methodologies and prediction of damage states both with earthquake damage data and with performance expectation of new buildings.
From page 145...
... • The difficulty of building an accurate inventory including the prevalence of specific seismic deficiencies prevents efficient identification of building/structural types to target for replacement or retrofit. TASK 14: PERFORMANCE-BASED EARTHQUAKE ENGINEERING FOR BUILDINGS Performance-based earthquake engineering enables decision-makers to target explicit levels of vulnerability for components of the built envi ronment in terms of their resilience (life safety, repair cost and business interruption)
From page 146...
... Continuing observation of the performance of structures under strong ground shaking, as well as a gradual increase in understanding of dynamic structural response to shaking, led to refinement of these design rules over the past 6 decades. Over that time, the performance goal of seismic design remained as "life safety" although the term was only vaguely defined.
From page 147...
... There are great uncertainties related to all aspects of these calculations, including what intensity of ground motion is expected; the exact characteristics of the ground motions; the accuracy of the computer model and the analysis method; the nature of the damage to the structural framing, nonstructural components, and building contents; and the consequences of this damage. The Guidelines will explicitly consider all these uncertainties resulting in a relatively complex methodology that will have to be simplified for practical use.
From page 148...
... USGS should continue to update the National Seismic Hazard Maps and the associated design-oriented Java-based applets using new knowledge on earthquake ground motion, faults, and predictive relationships. • Predictive models of ground shaking and deformation are required for performance-based earthquake engineering.
From page 149...
... Reliable procedures to select and scale earthquake ground motions for design and assessment of structures, lifelines, and earthen structures must be developed. • Performance and loss computations are made by analysis of a numerical model(s)
From page 150...
... Performance assessment tools such as ASCE 41-06 and the draft ATC-58 methodology should be used to assess the likely performance of modern, codeconforming buildings as a function of framing-system type and height, local soil conditions, and geographic location (seismic hazard) and to inform future revisions of design codes and standards.
From page 151...
... • A plan should be developed and executed to regularly revise guidelines, standards, and codes for performance-based design and assessment of buildings. Implementation Issues Issues associated with the effective implementation of performancebased earthquake engineering include the following items.
From page 152...
... This blackout affected 5 states, 50 million people, and caused an estimated $4-10 billion in business interruption losses in the central and eastern United States (U.S.Canada Power System Outage Task Force, 2004)
From page 153...
... . In 1998, a study on the effects of a large New Madrid earthquake in the central United States estimated that direct and indirect business interruption economic losses due to extended power disruption could be as high as $3 billion (Shinozuka et al., 1998)
From page 154...
... NEHRP collaboration with Standards Developing Organizations can facilitate these types of reviews and coordinate code and standard updates that reference the latest edition of the National Seismic Hazard Maps.
From page 155...
... Lifeline Earthquake Engineering Research The 1906 San Francisco and 1933 Long Beach, CA, earthquakes dem onstrated the consequences of multiple lifeline systems failures on a community. Although the severe effects of these earthquakes spurred the initial development of seismic design requirements in buildings and other structures in California, lessons on the need for rapid restoration of lifelines to aid in community response waned as a result of the lack of a significantly damaging urban earthquake for nearly 4 decades after 1933.
From page 156...
... MCEER focused on the use of advanced and emerging technologies for reducing impacts and developing methods to quantify community resilience. All three earthquake engineering centers are also participants in the NSF-funded NEES program.33 NSF funding for these engineering research centers has now ceased, and the level of center-based research on lifelines has decreased substantially.
From page 157...
... ALA's objectives were to facilitate the creation, adoption, and implementation of national consensus standards and guidelines to improve lifeline performance during hazard events. The ALA strategy focused on using the best industry practices, involving Standards Development Organizations (SDO)
From page 158...
... In addition to mapping geologic hazards along lifeline corridors, geotechnical research to improve strong ground motion (wave passage, spatial coherency, and duration effects) , ground displacement/deformation (fault rupture, landslides, liquefaction)
From page 159...
... Investment Priorities Various stakeholders, both public and private, have competing priorities for risk management investments. In some cases those investments can be at the expense of or delay seismic mitigation activities such as equip ment or building retrofits, especially in areas of perceived low seismic hazard or risk.
From page 160...
... Buildings constructed with these components should enhance the earthquake resilience of the built environment. Adaptive components and framing systems have been proposed in the form of semi-active and actively controlled components and structures but have not been implemented in buildings and other structures in the United States.
From page 161...
... • Conduct moderate-scale and full-scale tests of components constructed with new materials using NEES infrastructure to characterize component response in sufficient detail to enable the development of design equations suitable for inclusion in a materials standard, hysteretic models for nonlinear response analysis, and fragility functions for performance-based seismic design and assessment. • Conduct near full-scale tests of complete three-dimensional framing systems constructed using new materials and/or components using NEES infrastructure and/or the E-Defense34 earthquake simulator.
From page 162...
... • Conduct moderate-scale and full-scale tests of adaptive components using NEES infrastructure to characterize component response in sufficient detail to enable the development of design equations suitable for inclusion in guidelines and standards, hysteretic models for nonlinear response analysis, and fragility functions for performance-based seismic design and assessment. • Conduct near full-scale tests of complete three-dimensional framing systems constructed using adaptive components using NEES infra structure and/or the E-Defense earthquake simulator.
From page 163...
... Notable exceptions are NEHRP's support of development of seismic standards and codes for buildings during the past 30 years and support since 2007 of research synthesis and technology transfer to the design professional community through the NEHRP Consultants Joint Venture. Continued support for these programs is needed.
From page 164...
... There are no systematic programs to consolidate and transfer research results to practice in many disciplinary areas that contribute to seismic resilience such as geotechnical engineering, seismic protection of infrastructure, use of scenarios and regional loss estimation, emergency response, postearthquake economic recovery, and public policy. Seismic safety and community resilience is only one of many issues facing most of the implementation community, including owners of buildings and infrastructure, policy-makers at all levels of government, engineers and planners, and the general public.
From page 165...
... Governments, at all levels, own part of the earthquake risk and are better able to carry out their responsibilities when people and businesses are earthquake resilient. Private investments in resilience have public benefits.
From page 166...
... NEHRP should develop a comprehensive strategy -- from concept to practice -- that addresses the people at the community and regional levels who are responsible for earthquake risk and the ensuing consequences. This will require innovations -- ideas, practices, or objects that are perceived as new by an individual or local unit that can adopt them.
From page 167...
... Diffusion theory applies to earthquake risk reduction efforts because the main goal is to change people's behavior so they will take actions to reduce their risk, as opposed to doing nothing or taking actions that actually increase their risk. Behavior change is not an engineering problem, and therefore reducing earthquake risk requires theories and methods from other fields.
From page 168...
... • A demonstration component, perhaps projects to reduce earthquake risk in schools, which would attract attention and demonstrate the value and feasibility of mitigation projects. • An analysis component to identify gaps between resilience apacity c and loss estimation, using different earthquake scenarios.
From page 169...
... • Governments should champion social justice issues raised by variations in vulnerability to earthquake risk; earthquake resilience should not be reserved for those with resources and position. • The NEHRP implementation program needs to advocate incentives to promote the societal benefits from earthquake risk management practices, and to remove obstacles and disincentives.


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