Neal Simon Kwong, PhD (Former Employee)
Science and Products
Data Release for the 2023 U.S. 50-State National Seismic Hazard Model - Overview
This data release contains data sets associated with the 2023 50-State National Seismic Hazard Model Update. The 2023 50-State National Seimsic Hazard Model (NSHM) Update includes an update to the NSHMs for the conterminous U.S (CONUS, last updated in 2018), Alaska (AK, last updated in 2007), and Hawaii (last updated in 2001). Data sets include inputs like seismicity catalogs used as input to the
The 2023 US 50-State National Seismic Hazard Model: Overview and implications
The US National Seismic Hazard Model (NSHM) was updated in 2023 for all 50 states using new science on seismicity, fault ruptures, ground motions, and probabilistic techniques to produce a standard of practice for public policy and other engineering applications (defined for return periods greater than ∼475 or less than ∼10,000 years). Changes in 2023 time-independent seismic hazard (both increase
Authors
Mark D. Petersen, Allison Shumway, Peter M. Powers, Ned Field, Morgan P. Moschetti, Kishor S. Jaiswal, Kevin R. Milner, Sanaz Rezaeian, Arthur Frankel, Andrea L. Llenos, Andrew J. Michael, Jason M. Altekruse, Sean Kamran Ahdi, Kyle Withers, Charles Mueller, Yuehua Zeng, Robert E. Chase, Leah M. Salditch, Nico Luco, Kenneth S. Rukstales, Julie A Herrick, Demi Leafar Girot, Brad T. Aagaard, Adrian Bender, Michael L. Blanpied, Richard W. Briggs, Oliver S. Boyd, Brandon Clayton, Christopher DuRoss, Eileen L. Evans, Peter J. Haeussler, Alexandra Elise Hatem, Kirstie Lafon Haynie, Elizabeth H. Hearn, Kaj M. Johnson, Zachary Alan Kortum, N. Simon Kwong, Andrew James Makdisi, Henry (Ben) Mason, Daniel McNamara, Devin McPhillips, P. Okubo, Morgan T. Page, Frederick Pollitz, Justin Rubinstein, Bruce E. Shaw, Zheng-Kang Shen, Brian Shiro, James Andrew Smith, William J. Stephenson, Eric M. Thompson, Jessica Ann Thompson Jobe, Erin Wirth, Robert C. Witter
A methodology to combine shaking and ground failure models for forecasting seismic damage to buried pipeline networks
How does an earthquake affect buried pipeline networks? It is well known that the seismic performance of buried pipelines depends on ground failures (GFs) as well as strong ground shaking (SGS), but it is unclear how the various types of earthquake hazards should be collectively combined, as existing methodologies tend to examine each of the earthquake hazards separately. In this article, we devel
Authors
N. Simon Kwong, Kishor S. Jaiswal
Uses of epistemic uncertainties in the USGS National Seismic Hazard Models
The need for US Geological Survey (USGS) National Seismic Hazard Models (NSHMs) to report estimates of epistemic uncertainties in the hazard (e.g. fractile hazard curves) in all forthcoming releases is increasing. With fractile hazard curves as potential new outputs from the USGS 2023 NSHM, a simultaneous need is to help end-users better understand these epistemic uncertainties and clarify their p
Authors
N. Simon Kwong, Kishor S. Jaiswal
Ground motion selection for nonlinear response history analyses of concrete dams
Evaluating the seismic performance of a 3D concrete dam using nonlinear response history analysis (NLRHA) requires three orthogonal components of ground acceleration histories, or ground motions (GMs) for brevity. Although much progress has been made for the topic of ground motion selection and modification (GMSM) in the context of multistory buildings, NLRHA of dams requires at least two addition
Authors
N. Simon Kwong
Preliminary national-scale seismic risk assessment of natural gas pipelines in the United States
Although the gas pipeline infrastructure in the United States is vulnerable to the seismic hazards of (i) strong ground shaking, and (ii) ground failures induced by surface faulting, liquefaction, or landslides, limited national guidance exists for operators to consistently evaluate the earthquake response of their pipelines. To provide additional information for stakeholders and establish more co
Authors
N. Simon Kwong, Kishor S. Jaiswal, Nico Luco, J. W. Baker, K. A. Ludwig
Assessing direct and indirect long-term economic impacts from earthquakes to the U.S. National Bridge Inventory
Using the 2018 National Seismic Hazard Model and the 2018 National Bridge Inventory, an annualized earthquake loss (AEL) study was conducted for approximately 610,000 bridges in the conterminous United States, quantifying both direct and indirect economic losses. The typical AEL framework has been augmented with new replacement unit cost data and bridge-specific parameters for modifying default fr
Authors
Kishor S. Jaiswal, N. Simon Kwong, Doug Bausch, David J. Wald, Kuo-wan Lin, Sharon Yen, Jerry Shen, Jeffrey Ger
A theoretical framework for integrating ground failure models into regional seismic performance assessments of buried pipelines
A variety of models exist for characterizing earthquake-induced ground failures, but application of these models towards regional seismic performance assessments of buried pipelines remains challenging. One challenge is that ground failures often occur at localized geospatial scales while buried pipelines are spatially distributed over long distances. In this study, we propose a theoretical framew
Authors
N. Simon Kwong, Kishor S. Jaiswal
Open-source resources help navigate new IM regulations
The revision of federal safety regulations for integrity management of gas transmission pipelines to require explicit consideration of seismicity increases the importance for operators to be actively identifying high-consequence areas (HCAs), evaluating seismic-related threats, and choosing a risk model to support risk management decisions. To ensure equal access to information by both operators a
Authors
N. Simon Kwong, Kishor S. Jaiswal, J. W. Baker, Nico Luco, K. A. Ludwig, Vasey J. Stephens
Earthquake risk of gas pipelines in the conterminous United States and its sources of uncertainty
Relatively little research has been conducted to systematically quantify the nationwide earthquake risk of gas pipelines in the US; simultaneously, national guidance is limited for operators across the country to consistently evaluate the earthquake risk of their assets. Furthermore, many challenges and uncertainties exist in a comprehensive seismic risk assessment of gas pipelines. As a first sta
Authors
N. Simon Kwong, Kishor S. Jaiswal, Jack W. Baker, Nico Luco, K. A. Ludwig, Vasey J. Stephens
Selecting three components of ground motions from Conditional Spectra for multiple stripe analyses
For complex structures where the seismic response depends appreciably on the vertical (V) component of ground motion (GM) (e.g., base-isolated buildings, long-span bridges, dams, nuclear power plants), incremental dynamic analysis (IDA) is commonly utilized to estimate seismic risk, where the V components of GM are selected and scaled based on the corresponding horizontal (H) components. The resul
Authors
N. Simon Kwong, Kishor S. Jaiswal, Nico Luco, J. W. Baker
Assessing the long-term earthquake risk for the US National Bridge Inventory (NBI)
We estimate annualized earthquake loss associated with over 600,000 bridges located throughout the contiguous United States. Each year, the Federal Highway Administration, in partnership with State Departments of Transportation, undertake a massive exercise to update the National Bridge Inventory (NBI) by combining data from states, federal agencies, local jurisdictions, and tribal governments. Th
Authors
Kishor S. Jaiswal, N. Simon Kwong, S. S. Yen, D. Bausch, Kuo-wan Lin, Nico Luco, David J. Wald, J. Rozelle
Non-USGS Publications**
Kwong NS and Chopra AK. (2019). “Selecting, scaling, and orienting three components of ground motions for intensity-based assessments at far-field sites.” Earthquake Spectra, DOI: 10.1177/8755293019899954.
Kwong NS and Chopra AK. The CMS-UHS Composite Spectrum for intensity-based assessments of tall buildings. Proceedings of the 11th National Conference in Earthquake Engineering, Earthquake Engineering Research Institute, Los Angeles, CA, 2018.
Kwong NS. A method for selecting hazard-consistent ground motions and estimating seismic demand hazard curves. Proceedings of the 16th World Conference on Earthquake Engineering, Chilean Association of Seismology and Earthquake Engineering, Santiago, Chile, 2017.
Kwong NS and Chopra AK. (2016). “A Generalized Conditional Mean Spectrum and its application for intensity-based assessments of seismic demands.” Earthquake Spectra, 33(1), 123–143; DOI: 10.1193/040416EQS050M
Kwong NS and Chopra AK. (2015). “Evaluation of the Exact Conditional Spectrum and Generalized Conditional Intensity Measure methods for ground motion selection.” Earthquake Engineering and Structural Dynamics, 45(5), 757-777; DOI: 10.1002/eqe.2683.
Kwong NS, Chopra AK, McGuire RK. (2015). “Evaluation of ground motion selection and modification procedures using synthetic ground motions.” Earthquake Engineering and Structural Dynamics, 44(11), 1841–1861; DOI: 10.1002/eqe.2558.
Kwong NS, Chopra AK, McGuire RK. (2014). “A framework for the evaluation of ground motion selection and modification procedures.” Earthquake Engineering and Structural Dynamics, 44(5), 795–815; DOI: 10.1002/eqe.2502.
Kalkan E, and Kwong NS, (2013). “Pros and cons of rotating ground motion records to fault-normal/parallel directions for response history analysis of buildings.” ASCE Journal of Structural Engineering, 140(3), 04013062.
Kalkan E, and Kwong NS, (2012). “Assessment of Modal Pushover-based Scaling procedure for nonlinear response history analysis of ordinary standard bridges.” ASCE Journal of Bridge Engineering, 17(2), 272–288.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Data Release for the 2023 U.S. 50-State National Seismic Hazard Model - Overview
This data release contains data sets associated with the 2023 50-State National Seismic Hazard Model Update. The 2023 50-State National Seimsic Hazard Model (NSHM) Update includes an update to the NSHMs for the conterminous U.S (CONUS, last updated in 2018), Alaska (AK, last updated in 2007), and Hawaii (last updated in 2001). Data sets include inputs like seismicity catalogs used as input to the
The 2023 US 50-State National Seismic Hazard Model: Overview and implications
The US National Seismic Hazard Model (NSHM) was updated in 2023 for all 50 states using new science on seismicity, fault ruptures, ground motions, and probabilistic techniques to produce a standard of practice for public policy and other engineering applications (defined for return periods greater than ∼475 or less than ∼10,000 years). Changes in 2023 time-independent seismic hazard (both increase
Authors
Mark D. Petersen, Allison Shumway, Peter M. Powers, Ned Field, Morgan P. Moschetti, Kishor S. Jaiswal, Kevin R. Milner, Sanaz Rezaeian, Arthur Frankel, Andrea L. Llenos, Andrew J. Michael, Jason M. Altekruse, Sean Kamran Ahdi, Kyle Withers, Charles Mueller, Yuehua Zeng, Robert E. Chase, Leah M. Salditch, Nico Luco, Kenneth S. Rukstales, Julie A Herrick, Demi Leafar Girot, Brad T. Aagaard, Adrian Bender, Michael L. Blanpied, Richard W. Briggs, Oliver S. Boyd, Brandon Clayton, Christopher DuRoss, Eileen L. Evans, Peter J. Haeussler, Alexandra Elise Hatem, Kirstie Lafon Haynie, Elizabeth H. Hearn, Kaj M. Johnson, Zachary Alan Kortum, N. Simon Kwong, Andrew James Makdisi, Henry (Ben) Mason, Daniel McNamara, Devin McPhillips, P. Okubo, Morgan T. Page, Frederick Pollitz, Justin Rubinstein, Bruce E. Shaw, Zheng-Kang Shen, Brian Shiro, James Andrew Smith, William J. Stephenson, Eric M. Thompson, Jessica Ann Thompson Jobe, Erin Wirth, Robert C. Witter
A methodology to combine shaking and ground failure models for forecasting seismic damage to buried pipeline networks
How does an earthquake affect buried pipeline networks? It is well known that the seismic performance of buried pipelines depends on ground failures (GFs) as well as strong ground shaking (SGS), but it is unclear how the various types of earthquake hazards should be collectively combined, as existing methodologies tend to examine each of the earthquake hazards separately. In this article, we devel
Authors
N. Simon Kwong, Kishor S. Jaiswal
Uses of epistemic uncertainties in the USGS National Seismic Hazard Models
The need for US Geological Survey (USGS) National Seismic Hazard Models (NSHMs) to report estimates of epistemic uncertainties in the hazard (e.g. fractile hazard curves) in all forthcoming releases is increasing. With fractile hazard curves as potential new outputs from the USGS 2023 NSHM, a simultaneous need is to help end-users better understand these epistemic uncertainties and clarify their p
Authors
N. Simon Kwong, Kishor S. Jaiswal
Ground motion selection for nonlinear response history analyses of concrete dams
Evaluating the seismic performance of a 3D concrete dam using nonlinear response history analysis (NLRHA) requires three orthogonal components of ground acceleration histories, or ground motions (GMs) for brevity. Although much progress has been made for the topic of ground motion selection and modification (GMSM) in the context of multistory buildings, NLRHA of dams requires at least two addition
Authors
N. Simon Kwong
Preliminary national-scale seismic risk assessment of natural gas pipelines in the United States
Although the gas pipeline infrastructure in the United States is vulnerable to the seismic hazards of (i) strong ground shaking, and (ii) ground failures induced by surface faulting, liquefaction, or landslides, limited national guidance exists for operators to consistently evaluate the earthquake response of their pipelines. To provide additional information for stakeholders and establish more co
Authors
N. Simon Kwong, Kishor S. Jaiswal, Nico Luco, J. W. Baker, K. A. Ludwig
Assessing direct and indirect long-term economic impacts from earthquakes to the U.S. National Bridge Inventory
Using the 2018 National Seismic Hazard Model and the 2018 National Bridge Inventory, an annualized earthquake loss (AEL) study was conducted for approximately 610,000 bridges in the conterminous United States, quantifying both direct and indirect economic losses. The typical AEL framework has been augmented with new replacement unit cost data and bridge-specific parameters for modifying default fr
Authors
Kishor S. Jaiswal, N. Simon Kwong, Doug Bausch, David J. Wald, Kuo-wan Lin, Sharon Yen, Jerry Shen, Jeffrey Ger
A theoretical framework for integrating ground failure models into regional seismic performance assessments of buried pipelines
A variety of models exist for characterizing earthquake-induced ground failures, but application of these models towards regional seismic performance assessments of buried pipelines remains challenging. One challenge is that ground failures often occur at localized geospatial scales while buried pipelines are spatially distributed over long distances. In this study, we propose a theoretical framew
Authors
N. Simon Kwong, Kishor S. Jaiswal
Open-source resources help navigate new IM regulations
The revision of federal safety regulations for integrity management of gas transmission pipelines to require explicit consideration of seismicity increases the importance for operators to be actively identifying high-consequence areas (HCAs), evaluating seismic-related threats, and choosing a risk model to support risk management decisions. To ensure equal access to information by both operators a
Authors
N. Simon Kwong, Kishor S. Jaiswal, J. W. Baker, Nico Luco, K. A. Ludwig, Vasey J. Stephens
Earthquake risk of gas pipelines in the conterminous United States and its sources of uncertainty
Relatively little research has been conducted to systematically quantify the nationwide earthquake risk of gas pipelines in the US; simultaneously, national guidance is limited for operators across the country to consistently evaluate the earthquake risk of their assets. Furthermore, many challenges and uncertainties exist in a comprehensive seismic risk assessment of gas pipelines. As a first sta
Authors
N. Simon Kwong, Kishor S. Jaiswal, Jack W. Baker, Nico Luco, K. A. Ludwig, Vasey J. Stephens
Selecting three components of ground motions from Conditional Spectra for multiple stripe analyses
For complex structures where the seismic response depends appreciably on the vertical (V) component of ground motion (GM) (e.g., base-isolated buildings, long-span bridges, dams, nuclear power plants), incremental dynamic analysis (IDA) is commonly utilized to estimate seismic risk, where the V components of GM are selected and scaled based on the corresponding horizontal (H) components. The resul
Authors
N. Simon Kwong, Kishor S. Jaiswal, Nico Luco, J. W. Baker
Assessing the long-term earthquake risk for the US National Bridge Inventory (NBI)
We estimate annualized earthquake loss associated with over 600,000 bridges located throughout the contiguous United States. Each year, the Federal Highway Administration, in partnership with State Departments of Transportation, undertake a massive exercise to update the National Bridge Inventory (NBI) by combining data from states, federal agencies, local jurisdictions, and tribal governments. Th
Authors
Kishor S. Jaiswal, N. Simon Kwong, S. S. Yen, D. Bausch, Kuo-wan Lin, Nico Luco, David J. Wald, J. Rozelle
Non-USGS Publications**
Kwong NS and Chopra AK. (2019). “Selecting, scaling, and orienting three components of ground motions for intensity-based assessments at far-field sites.” Earthquake Spectra, DOI: 10.1177/8755293019899954.
Kwong NS and Chopra AK. The CMS-UHS Composite Spectrum for intensity-based assessments of tall buildings. Proceedings of the 11th National Conference in Earthquake Engineering, Earthquake Engineering Research Institute, Los Angeles, CA, 2018.
Kwong NS. A method for selecting hazard-consistent ground motions and estimating seismic demand hazard curves. Proceedings of the 16th World Conference on Earthquake Engineering, Chilean Association of Seismology and Earthquake Engineering, Santiago, Chile, 2017.
Kwong NS and Chopra AK. (2016). “A Generalized Conditional Mean Spectrum and its application for intensity-based assessments of seismic demands.” Earthquake Spectra, 33(1), 123–143; DOI: 10.1193/040416EQS050M
Kwong NS and Chopra AK. (2015). “Evaluation of the Exact Conditional Spectrum and Generalized Conditional Intensity Measure methods for ground motion selection.” Earthquake Engineering and Structural Dynamics, 45(5), 757-777; DOI: 10.1002/eqe.2683.
Kwong NS, Chopra AK, McGuire RK. (2015). “Evaluation of ground motion selection and modification procedures using synthetic ground motions.” Earthquake Engineering and Structural Dynamics, 44(11), 1841–1861; DOI: 10.1002/eqe.2558.
Kwong NS, Chopra AK, McGuire RK. (2014). “A framework for the evaluation of ground motion selection and modification procedures.” Earthquake Engineering and Structural Dynamics, 44(5), 795–815; DOI: 10.1002/eqe.2502.
Kalkan E, and Kwong NS, (2013). “Pros and cons of rotating ground motion records to fault-normal/parallel directions for response history analysis of buildings.” ASCE Journal of Structural Engineering, 140(3), 04013062.
Kalkan E, and Kwong NS, (2012). “Assessment of Modal Pushover-based Scaling procedure for nonlinear response history analysis of ordinary standard bridges.” ASCE Journal of Bridge Engineering, 17(2), 272–288.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.