About

Gregory Deierlein is the John A. Blume Professor in the School of Engineering at Stanford University. His research focuses on improving limit states design of constructed facilities through the development and application of nonlinear structural analysis methods and performance-based design criteria. His recent projects include the development and application of strength and stiffness degrading models to simulate steel and reinforced concrete structures, seismic design and behavior of composite steel-concrete buildings, analysis of inelastic torsional-flexural instability of steel members, and a fracture mechanics investigation of seismically designed welded steel connections. He holds a PhD from the University of Texas, Austin, an MS from the University of California at Berkeley, and a BS from Cornell University.

Research topics

• Computer Science
• Engineering
• Physics
• Structural engineering
• Materials science
• Medicine
• Mechanics
• Database
• Risk analysis (engineering)
• Thermodynamics
• Medical emergency
• Composite material
• Systems engineering
• Data science

Selected publications

• Exposure matters: A synthesis framework for high-resolution building inventory development

  International Journal of Disaster Risk Reduction · 2026-04-15 · 1 citations

  articleOpen accessSenior author
  PublisherDOI

• Systematic Training and Validation of Parameterized Probabilistic Learning on Manifolds Surrogate Model for Seismic Performance Assessment of Highway Bridges

  Earthquake Engineering & Structural Dynamics · 2025-08-28 · 2 citations

  articleSenior author

  ABSTRACT Surrogate modeling using Probabilistic Learning on Manifolds (PLoM) was found to be an effective and efficient approach for predicting site‐specific or structure‐specific collapse fragility and non‐collapse response demand distributions. This study extends the application of PLoM surrogate modeling to site‐and‐structure specific problems, which is a promising alternative to the computationally expensive ground motion selection and nonlinear response history analysis when assessing the seismic performance of highway bridges (e.g., peak response demand, cumulative damage, and collapse risk). A systematic procedure is proposed to train parameterized PLoM surrogate models from incremental dynamic analysis (IDA) data and predict site‐and‐structure‐specific collapse fragility and non‐collapse engineering demand parameter (EDP) distributions for highway bridges. A quasi‐stripe training approach is illustrated to effectively tune two PLoM hyperparameters and as functions of spectral acceleration intensity , which yields good model prediction accuracy at varying intensity levels. A comprehensive validation study is conducted on both the collapse and non‐collapse EDP predictions for nine different site‐bridge combinations of three California sites and three pre‐1971 two‐span single column bridges. The proposed training and prediction procedure is implemented to obtain PLoM prediction results, which are found to be in good agreement with multiple stripe analysis (MSA) results regarding (1) mean annual frequency of collapse, (2) probabilistic distribution of individual non‐collapse EDPs, and (3) correlation coefficients and empirical copulas between data dimensions.

  PublisherDOI

• How Exposure Data Synthesis Choices Shape our Understanding of Disaster Risk

  2025-12-24

  articleOpen accessSenior author

  High-fidelity regional simulations offer powerful tools for disaster risk management, providing rich quantitative insights into potential impacts and the effectiveness of mitigation strategies. The accuracy of these simulations, however, depends critically on detailed building exposure data, which is often aggregated, incomplete, or inconsistent across sources. This study presents 1) a systematic workflow for synthesizing multiple data sources to generate regional, footprint-level building inventories, and 2) a quantitative evaluation of how inventory development decisions impact seismic risk estimates. The workflow resolves disagreements between data sources with varying geometries and fills both random and systematic gaps. Using Hayward, CA as a case study, we demonstrate that the choice of data sources and synthesis methods creates significant, non-random differences in quantified seismic risk. These differences exhibit clear geospatial patterns and are linked to specific building features. To demonstrate this effect, we generate a set of plausible inventories for Hayward using nationally available data and simulate the impact of an M7 scenario earthquake for each. We then compare the resulting range of outcomes against results from two deterministic inventories: the widely-used National Structure Inventory and a “best estimate” inventory created using high-quality local data. Our findings reveal how uncertainty and bias are introduced during inventory development. This provides important caveats for regional risk assessments and identifies key priorities for future research aimed at improving the exposure data that underpins a broad range of disaster management applications.

  PublisherOA PDFDOI

• Data Screening and Synthesis to Develop High-Resolution Building Inventories for Regional Risk Assessment

  2025-12-16

  articleOpen accessSenior author

  High-fidelity regional simulations of the impact of natural hazards on the built environment can be used to support disaster risk management and guide mitigation priorities. These assessments are underpinned by building inventories. Historically, building inventory development has primarily been driven by insurance companies and government agencies, typically targeting aggregate risk and impact measures. The growing feasibility of modeling impacts beyond aggregate loss and the growing interest in regional risk studies from a broad range of stakeholders are creating a need for detailed footprint-level building inventories. Current research studies often use varied data sources to describe the building inventory or use variable single-use methods to synthesize multiple datasets; however, few have assessed the impact of these inventory development decisions or the variability of the results. This study presents 1) a systematic framework for creating footprint-level building inventories through the synthesis of multiple data sources, 2) specific implementation methods for various data types, and 3) a quantitative evaluation of how inventory development decisions impact the resulting inventory makeup and quality for a case study city. Results show that the choice of input data sources and synthesis methods can lead to substantial differences in the resulting inventory. Furthermore, these differences are geospatially clustered and concentrate in certain types of buildings, which can lead to significant biases in the results. These findings underscore the need for more systematic and standardized approaches to building inventory development for regional natural hazard risk assessments.

  PublisherDOI

• SUSTAINED AMPLITUDE (RSX) AND SIGNIFICANT DURATION (DA) SPECTRA FOR SEISMIC RISK ASSESSMENT IN SEDIMENTARY BASINS

  2025-12-18

  articleOpen accessSenior author
  PublisherOA PDFDOI

• An open-source simulation platform to support and foster research collaboration in natural hazards engineering

  Frontiers in Built Environment · 2025-08-05 · 6 citations

  articleOpen access

  Computational simulation is a critical tool for assessing the impacts of natural hazards and informing risk mitigation and resilience strategies. The NHERI SimCenter has developed an open-source, modular framework that integrates performance-based engineering methodologies with regional-scale assessments to enable multi-hazard, multi-scale simulations. This paper presents the conceptual foundation and current capabilities of the SimCenter platform, covering hazard characterization, structural response analysis, damage and loss estimation, and recovery modeling. By leveraging high-performance computing, standardized data schemas, and open-source tools, the platform facilitates transparent, reproducible research while bridging local and regional analyses. Key contributions include improved inventory generation, damage simulation, and recovery analysis, with applications extending across multiple hazard domains. The paper also discusses challenges in implementing high-resolution, high-fidelity simulations, advancing multi-hazard assessments, and enhancing accessibility for a broad user base. Looking ahead, expanding hazard models, refining regional-to-local modeling techniques, and fostering community collaboration will be essential for advancing computational simulation in natural hazards engineering. Through continued development, the SimCenter aims to provide researchers and practitioners with scalable, adaptable tools to enhance disaster risk assessment and resilience planning.

  PublisherOA PDFDOI

• Development and validation of a model to calculate full-range response of bolted angle cleats in bending

  Journal of Constructional Steel Research · 2025-02-17 · 6 citations

  articleOpen accessSenior author

  This study investigates the full-range behaviour of bolted angle steel cleats, commonly used in beam-column connections of steel structural frameworks. Eight experiments were conducted on bolted angle cleats in bending with four different configurations. Complementary finite element simulation models were developed, incorporating a ductile fracture model, termed Lode angle modified void growth model (LMVGM). The proposed finite element model effectively captures cracking in the angle cleats under multi-axial stresses and plastic strains. Test and finite element analysis results showed that the bolt gauge dimensions of the legs of the angle connected to the column and beam flanges (referred to as the column leg and beam leg, respectively) affect the fracture location, which tends to initiate within the plastic hinge line that forms in the column or beam leg with the larger bolt gauge. Specifically, the bolt gauge dimension refers to the distance between the angle heel and bolt hole centre on either column or beam leg. Additionally, a measurable reduction in the angle plate thickness (up to 14 % reduction) was observed in the plastic hinges due to the presence of high tensile stresses resulting from the tensile membrane action developed in the transverse direction of each leg under large deformations. Based on observations from the tests and finite element simulations, a theoretical model is proposed to predict the full-range behaviour of angle cleats. The theoretical model incorporates the gradual formation of a plastic bending mechanism, nonlinear response due to material yielding and large-deformation response (membrane action), reductions in plate thickness and bending strength due to local plastic flow in the plate hinges, and bolt slippage. The proposed model was validated using the angle cleat tests presented herein, showing substantially better accuracy than the model codified in EN 1993-1-8. The proposed model was incorporated in the Generalised Component Method to simulate the moment-rotational responses of published bolted angle connection tests. The proposed model is shown to provide more accurate response curves compared to Generalised Component Method analyses that employ existing angle cleat models. • Experimental investigation of angle cleat with varying bolt gauges. • Finite element modelling with accurate simulation of fracture initiation and propagation. • Theoretical model for calculating full-range response of bolted angle cleats in bending. • Equations accounting for the reduction in angle plate thickness.

  PublisherDOI

• Digitally Augmented Database of Fracture-Critical Steel Beam-to-Column Connection Tests

  Journal of Structural Engineering · 2025-02-10

  article

  This paper describes a recently compiled database of 100 full-scale steel beam-to-column connections that failed due to flange fractures. This database focuses on welded flange connections tested in the past 50 years, including tests with strong panel zones and box columns that have been excluded from previous collections. This database is augmented with high-fidelity structural models carefully calibrated to the test data using a semiautomatic algorithm to extend the information from each experiment beyond the recorded response. Once calibrated, these models offer a versatile method to decompose the total displacement response of the connections in beam, panel zone, and column deformations and extract more detailed response quantities, such as the stress history of the flange. This augmented database enables a deeper understanding of the causes of flange fractures and an assessment of the common rotation limits in ASCE/SEI 41 employed for simulating fracture. The results show that these rotation limits have a considerably large error. Furthermore, these rotation limits are incapable of either identifying the flange that would fracture first or simulating the opening and closing behavior of a fractured flange. The stress histories of the flange extracted using the models is a more efficient demand parameter for characterizing fracture behavior. This database is openly available in the DesignSafe DataDepot and is immediately useful for researchers developing new models for beam-to-column connections susceptible to fracture and to practicing engineers interested in calibrating structural models for nonlinear dynamic analysis.

  PublisherDOI

• Ductile Fracture Simulation of Shear-Out Strength Behavior and Design Equations of Bolted Lap Joints

  Journal of Structural Engineering · 2025-06-30 · 6 citations

  articleSenior author

  This paper presents a detailed study of the fracture behavior and ultimate resistance of bolted lap joints that fail by shear-out rupture, including laboratory tests, detailed computational simulations of ductile fracture, and theoretical development of design strength equations. Four double-bolted lap joints were tested to provide validation data for shear-out failure and tension rupture. Parallel finite element models were developed to simulate the lap joints, incorporating two ductile fracture criteria whose parameters were calibrated by 12 coupon tests. The finite element model accurately simulated large-scale yielding, ductile fracture, and the influence of frictions at bolt shank-to-ply interface as well as ply-to-ply interface on the shear-out capacity of the joints. New design formulas are proposed to determine the ultimate shear-out strength, considering the friction between the bolt shank and ply plate as well as the ply plate and bolt geometry. The proposed design equations consider the distribution of shear stresses around the bolt hole and thus can accurately predict the shear plane position. The proposed design equations are compared with finite element parametric studies as well as test results and strength predictions by existing design standards. The comparison demonstrates that the proposed equations provide improved prediction of shear-out capacity.

  PublisherDOI

• SCEC BROADBAND PLATFORM (BBP) GROUND MOTION SIMULATIONS FOR TALL BUILDING RESPONSE ANALYSES IN SAN FRANCISCO, LOS ANGELES DOWNTOWN, AND CYBERSHAKE SITES

  2025-12-17

  articleOpen accessSenior author
  PublisherOA PDFDOI

Recent grants

• Collaborative Research: Multi-Scale Simulation of Low-Triaxiality Fracture and Ultra Low Cycle Fatigue in Steel Structures

  NSF · $213k · 2008–2012

• NEESR: Seismically Isolated Unibody Residential Buildings for Enhanced Life-Cycle Performance

  NSF · $1.3M · 2011–2016

• Collaborative Research: Simulating Crack Propagation in Steel Structures Under Ultra-Low Cycle Fatigue and Low-Triaxiality Loading from Earthquakes and Other Hazards

  NSF · $340k · 2016–2021

• NEESR-SG: Controlled Rocking of Steel-Framed Buildings with Replaceable Energy Dissipating Fuses

  NSF · $1.4M · 2005–2011

• Integrated System and Component Reliability in Seismic Collapse Safety of Structures

  NSF · $400k · 2010–2016

Frequent coauthors

• Amit Kanvinde

  University of California, Davis

  60 shared

• Abbie B. Liel

  University of Colorado Boulder

  39 shared

• Curt B. Haselton

  Baker Engineering and Risk Consultants (United States)

  36 shared

• Jack W. Baker

  Stanford University

  36 shared

• Paul Cordova

  36 shared

• Keh‐Chyuan Tsai

  National Taiwan University

  33 shared

• W. C. Lai

  National Taipei University of Technology

  32 shared

• C. H. Chen

  32 shared

Education

• Ph.D., Civil Engineering

  Stanford University

  1995

• M.S., Civil Engineering

  Stanford University

  1991

• B.S., Civil Engineering

  University of California, Berkeley

  1989