Joel P. Conte

University of California, San Diego | UCSD · Department of Structural Engineering

Bayesian finite element (FE) model updating using direct model evaluations of large-scale high-fidelity FE models is extremely computationally expensive. Surrogate models can be used as fast emulators of FE models to accelerate the model calibration process. The physics/mechanics-based FE models are still the underpinning behind the surrogate model...

This paper presents the formulation of a comprehensive risk-targeted performance-based seismic design (PBSD) framework involving the seismic design of bridge piers for California Ordinary Standard Bridges (OSBs), facilitating risk-informed design and decision making in the face of uncertainty. A full-fledged implementation of this all-inclusive des...

This study complements and extends a recent work on the development of a rigorous framework for risk‐targeted performance‐based seismic design/assessment of ordinary standard bridges (OSBs) in California. Rooted in the formulation of this framework is an updated fully probabilistic performance‐based earthquake engineering (PBEE) assessment methodol...

This paper proposes an approach to select a maintenance strategy from a predefined set of choices considering the decision maker’s behavioral risk profile. It is assumed that the damage state is characterized by a continuous state parameter probabilistically inferred from observable sensor data. This work applies an engineering application of conse...

Recently, there have been a lot of applications in multiblock structures. At CERN, concrete blocks are stacked to make walls in order to shield radiation from particle colliders. At Energy Vault, multiblock tower structures are designed for renewable energy storage. In this talk, we present our work in seismic performance assessment of those multib...

Recently, there have been a lot of applications in multiblock structures. At CERN, concrete blocks are stacked to make walls in order to shield radiation from particle colliders. At Energy Vault, multiblock tower structures are designed for renewable energy storage. In this talk, we present our work in seismic performance assessment of those multib...

Accounting for model form uncertainty is one of the key challenges in the model calibration of physical systems. It has been traditionally ignored (or not properly accounted for) in the model calibration of structural systems. The state-of-the-art Kennedy and O'Hagan (KOH) approach to account for model form uncertainty has only been applied for cal...

Bayesian calibration plays a vital role in improving the validity of computational models’ predictive power. However, the presence of unobservable distributed responses and uncertain model parameters in multi-level models poses challenges to Bayesian calibration, due to the lack of direct observations and the difficulty in identifying the hidden an...

Accounting for model form uncertainty is one of the key challenges in the model calibration of physical systems. It has been traditionally ignored (or not properly accounted for) in the model calibration of structural systems. The state-of-the-art Kennedy and O’Hagan (KOH) approach to account for model form uncertainty has only been applied for cal...

Accounting for model form uncertainty is one of the key challenges in the model calibration of physical systems. It has been traditionally ignored (or not properly accounted for) in the model calibration of structural systems. The state-of-the-art Kennedy and O'Hagan (KOH) approach to account for model form uncertainty has only been applied for cal...

A promising and attractive way of performing structural health monitoring (SHM) and damage prognosis (DP) of engineering systems is through utilizing a nonlinear finite element (FE) model. Often, FE models contain parameters that are unknown or known with significant level of uncertainty. Such parameters need to be estimated/updated/calibrated usin...

Damage detection (DD) is one of the primary goals of health monitoring of civil structures. Vibration-based techniques aim to identify the modal properties (or vibration characteristics) of structures and are one of the most popular approaches for structural damage detection. The use of vibration characteristics (natural frequencies, damping ratios...

A mechanics-based virtual model of the NHERI@UCSD large high-performance outdoor shake table (LHPOST) in its uniaxial configuration and under bare table condition is presented. The virtual model includes: (i) a reprogrammed version (i.e., virtual replica) of the actual controller, (ii) a servovalve model including servovalve spool dynamics and two...

This paper presents the analysis of the seismic response and the identification of the dynamic properties of an equivalent linear time-invariant model of a full-scale five-story base-isolated reinforced concrete building tested on the unidirectional NEES@UCSD shake table. A sequence of seven scaled historic earthquake records was applied by the sha...

Motivated by the need to evaluate the seismic response of large capacity gravity energy storage systems (potential energy batteries) such as the proposed frictional Multiblock Tower Structures (MTS) recently discussed by Andrade et al. [1], we apply Buckingham's Pi Theorem [2] to identify the most general forms of dimensionless numbers and dynamic...

With the recent advent of performance‐based earthquake engineering (PBEE) in seismic design practice of buildings serving as an impetus for this work, initial steps toward a fully probabilistic performance‐based seismic design (PBSD) method for bridges, a less trodden area in terms of PBEE applications, are taken herein by assembling an updated pro...

This report is a product of the NHERI SimCenter under the auspices of the U.S. National Science Foundation (NSF). It provides an overview and review of simulation requirements and software tools for natural hazards engineering (NHE) of the built environment. The simulations discussed in this report are an essential component of research to address...

Since its commissioning in 2004, the UC San Diego Large High-Performance Outdoor Shake Table (LHPOST) has enabled the seismic testing of large structural, geostructural and soil-foundation-structural systems, with its ability to accurately reproduce far- and near-field ground motions. Thirty-four (34) landmark projects were conducted on the LHPOST...

Digital twin-based approaches for structural health monitoring (SHM) and damage prognosis (DP) are emerging as a powerful framework for intelligent maintenance of civil structures and infrastructure systems. Model updating of nonlinear mechanics-based Finite Element (FE) models using input and output measurement data with advanced Bayesian inferenc...

Digital twin-based approaches for structural health monitoring (SHM) and damage prognosis (DP) are emerging as a powerful framework for intelligent maintenance of civil structures and infrastructure systems. Model updating of nonlinear mechanics-based Finite Element (FE) models using input and output measurement data with advanced Bayesian inferenc...

Continuous monitoring of miter gates used in navigation locks is desirable in order to prioritize maintenance and avoid unexpected failures. Substantial economic losses to the marine cargo and associated industries are caused by the closure of these inland waterway structures. Strain gauges are often installed in many of these miter gates for data...

Increasingly, seismic isolation (SI) has been adopted in buildings and highway bridges to mitigate damage from earthquakes. However, its appropriateness in high-speed rail (HSR) bridges remains a topic of major concern for engineers and stakeholders. The effects of SI on the response of HSR bridge systems during future earthquakes need to be evalua...

Dynamic measurements are undertaken on a utility scale wind turbine (900 kW rated power, 55 m hub height, and a 53.6 m rotor diameter) located at Oak Creek Energy Systems near Mojave, California, USA. The acceleration response to wind and other ambient sources is recorded by as many as 81 channels at locations along the height of the tower, on the...

This paper presents an information-theoretic approach for identifiability assessment of model parameters in nonlinear finite-element (FE) model updating problems. Rooted in the Bayesian inference method, the proposed approach uses the Shannon information entropy as a measure of uncertainty in the model parameters. The difference in the entropy of a...

In this paper, nonlinear finite element model updating (FEMU) is performed to study the prediction accuracy of a state-ofthe-art finite element (FE) model of a seismic isolated bridge (SIB). The seismic isolator model parameters are updated in two phases: using component-wise and system-wise FEMU. The isolator model parameter values estimated from...

Un edificio de 5 pisos de hormigón armado fue ensayado a escala real el año 2012 en la mesa de vibrar de la Universidad de California, San Diego. Este programa experimental fue realizado con el fin de mejorar la compresión del comportamiento y desempeño sísmico de componentes no-estructurales. Para esto, el edificio ensayado fue equipado con una am...

This paper presents a framework for the identification of nonlinear finite element (FE) structural models using Bayesian inference methods. Using the input-output dynamic data recorded during an earthquake event, batch and recursive Bayesian estimation methods are employed to update a mechanics-based nonlinear FE model of the structure of interest...

This report is a product of the NSF NHERI SimCenter and provides an overview and review of simulation requirements and software tools for natural hazards engineering of the built environment. The simulations discussed in this report are an essential component of research to address the three grand challenge areas and associated research questions o...

A novel approach to deal with modeling uncertainty when updating mechanics-based finite element (FE) models is presented. In this method, a dual adaptive filtering approach is adopted, where the Unscented Kalman filter (UKF) is used to estimate the unknown parameters of the nonlinear FE model and a linear Kalman filter (KF) is employed to estimate...

Bayesian nonlinear finite element (FE) model updating using input and output measurements have emerged as a powerful technique for structural health monitoring (SHM), and damage diagnosis and prognosis of complex civil engineering systems. The Bayesian approach to model updating is attractive because it provides a rigorous framework to account for...

This paper proposes a novel approach to deal with modeling uncertainty when updating mechanics-based nonlinear finite element (FE) models. In this framework, a dual adaptive filtering approach is adopted, where the Unscented Kalman filter (UKF) is used to estimate the unknown parameters of the nonlinear FE model and a linear Kalman filter (KF) is e...

This paper presents an information-theoretic approach for identifiability assessment of model parameters in nonlinear FE model updating problems. Rooted in the Bayesian inference method, the proposed approach uses the Shannon information entropy as a measure of uncertainty in the model parameters. The difference in the entropy of a priori and a pos...

15 This paper presents an information-theoretic approach for identifiability assessment of model 16 parameters in nonlinear FE model updating problems. Rooted in the Bayesian inference method, 17 the proposed approach uses the Shannon information entropy as a measure of uncertainty in the 18 model parameters. The difference in the entropy of a prio...

Finite element (FE) model updating has emerged as a powerful technique for structural health monitoring and damage identification of civil structures. Updating mechanics-based nonlinear FE models allows for a complete and comprehensive damage diagnosis of large and complex structures, but it is computationally demanding. This paper first introduces...

This paper presents a new framework for output-only nonlinear system and damage identification of civil structures. This framework is based on nonlinear finite element (FE) model updating in the time-domain, using only the sparsely measured structural response to unmeasured or partially measured earthquake excitation. The proposed framework provide...

A full-scale five-story reinforced concrete building specimen, outfitted with a variety of nonstructural components and systems (NCSs), was built and tested on the Network for Earthquake Engineering Simulation at the University of California, San Diego (NEES–UCSD) large outdoor shake table in the period March 2011–June 2012. The building specimen w...

In this paper, nonlinear finite element model updating (FEMU) is performed to study the prediction accuracy of a state-of-the-art finite element (FE) model of a seismic isolated bridge (SIB). The seismic isolator model parameters are updated in two phases: using component-wise and system-wise FEMU. The isolator model parameter values estimated from...

This paper presents a framework for nonlinear system identification of civil structures using sparsely measured dynamic output response of the structure. Using a sequential maximum likelihood estimation (MLE) approach, the unknown FE model parameters, the measurement noise variances, and the input ground acceleration time histories are estimated jo...

The predominant period and corresponding equivalent viscous damping ratio, also known in various loading codes as effective period and effective damping coefficient, are two important parameters employed in the seismic design of base-isolated and conventional building structures. Accurate determination of these two parameters can reduce the uncerta...

Research, development, and applications in Experimental Vibration Analysis for Civil Engineering Structures are being fed by the continuous progress in the fields of sensor and testing technologies, instrumentation, data acquisition systems, computer technology, and computational modeling and simulation of large and complex civil infrastructure sys...

Previous comparison studies on seismic isolation have demonstrated its beneficial and detrimental effects on the structural performance of high-speed rail bridges during earthquakes. Striking a balance between these 2 competing effects requires proper tuning of the controlling design parameters in the design of the seismic isolation system. This re...

This paper presents a framework for nonlinear system identification of civil structures using sparsely measured dynamic output response of the structure. Using a sequential maximum likelihood estimation (MLE) approach, the unknown FE model parameters, the measurement noise variances, and the input ground acceleration time histories are estimated jo...

In this paper, nonlinear finite element model updating (FEMU) is performed to study the prediction accuracy of a state-of-the-art finite element (FE) model of a seismic isolated bridge (SIB). The seismic isolator model parameters are updated in two phases: using component-wise and system-wise FEMU. The isolator model parameter values estimated from...

A methodology is proposed to update mechanics-based nonlinear finite element (FE) models of civil structures subjected to unknown input excitation. The approach allows to jointly estimate unknown time-invariant model parameters of a nonlinear FE model of the structure and the unknown time histories of input excitations using spatially-sparse output...

Nonlinear finite element (FE) modeling has been widely used to investigate the effects of seismic isolation on the response of bridges to earthquakes. However, most FE models of seismic isolated bridges (SIB) have used seismic isolator models calibrated from component test data, while the prediction accuracy of nonlinear FE models of SIB is rarely...

The 15-story Alto Rio building built in 2006 in the city of Concepción, Chile, was the only modern building that collapsed catastrophically during the February 27, 2010 Mw 8.8 Maule earthquake, resulting in eight human casualties. This building was typical of many medium rise reinforced concrete bearing wall buildings designed and built in Chile du...

This chapter presents a framework for the identification of nonlinear finite element (FE) structural models using Bayesian inference methods. Using the input-output dynamic data recorded during an earthquake event, batch and recursive Bayesian estimation methods are employed to update a mechanics-based nonlinear FE model of the structure of interes...

This paper presents a framework for structural health monitoring (SHM) and damage identification of civil structures. This framework integrates advanced mechanics-based nonlinear finite element (FE) modeling and analysis techniques with a batch Bayesian estimation approach to estimate time-invariant model parameters used in the FE model of the stru...

Because of the emerging transportation needs, the California High-Speed Rail (CHSR) project has been launched after significant success of high-speed rail systems in different countries around the world. In seismic prone areas, such as California, the seismic risk imposed to high-speed rail bridges is of particular concern to stakeholders and struc...

This paper presents an approach for structural health monitoring by integrating nonlinear structural finite element (FE) models and Bayesian methods. Batch and recursive Bayesian estimation methods are used to calibrate/update a nonlinear structural FE model of a structure (e.g., building, bridge, dam, etc.) employing the input-output dynamic data...

This study focuses on the development of a novel framework for nonlinear system and damage identification of civil structures using only the measured dynamic response of the structure during an earthquake. The presented framework provides a computationally feasible methodology to update mechanics-based nonlinear finite element (FE) models of civil...

This paper investigates the seismic performance of a functional traction elevator as part of a full-scale five-story building shake table test program. The test building was subjected to a suite of earthquake input motions of increasing intensity, first while the building was isolated at its base and subsequently while it was fixed to the shake tab...

Accepted for publication in ASCE Journal of Structural Engineering - August 2017

Earthquake ground motion records are nonstationary in both amplitude and frequency content. However, the latter nonstationarity is typically neglected mainly for the sake of mathematical simplicity. To study the stochastic effects of the time-varying frequency content of earthquake ground motions on the seismic response of structural systems, a pai...

With the launch of the high-speed train project in California, the seismic risk is a crucial concern to the stakeholders. To investigate the seismic behavior of future California High-Speed Rail (CHSR) bridge structures, a 3D nonlinear finite-element model of a CHSR prototype bridge is developed. Soil-structure and track-structure interactions are...

A full-scale five-story reinforced concrete building was built and tested on the NEES-UCSD shake table during the period from May 2011 to May 2012. The purpose of this test program was to study the response of the structure and nonstructural components and systems (NCSs) and their dynamic interaction during seismic base excitation of different inte...

This paper presents a framework for the identification of mechanics-based nonlinear finite element (FE) models of civil structures using Bayesian methods. Batch and recursive Bayesian estimation methods, namely the Extended Kalman filter (EKF) and Unscented Kalman filter (UKF), are used to update a mechanics-based nonlinear FE model of the structur...

The seismic performance of isolated structures during recent earthquakes has shown the effectiveness of seismic isolators to mitigate and even avoid structural damage following strong events. Seismic isolation introduces a flexible horizontal interface with high internal damping between the sub- and superstructure. This results in an elongation of...

Identifiability of parametric models investigates the question of existence and uniqueness of the solution of the associated parameter estimation problem. The identifiability problem is closely related to the experimental design and optimal sensor placement problems, which respectively aim at designing the input excitation and sensor locations to m...

Nonstructural components and systems (NCSs) provide little to no load bearing capacity to a building; however, they are essential to support its operability. As a result, 75–85% of the initial building financial investment is associated with these elements. The vulnerability of NCSs even during low intensity earthquakes is repeatedly exposed, resul...

A full-scale five-story reinforced concrete building fully equipped with nonstructural components and systems (NCSs) was tested to a near collapse condition on the large outdoor shake table at the University of California, San Diego in 2012. This landmark test program was intended to advance the understanding of the seismic behavior of NCSs install...

A landmark experimental program was conducted to advance the understanding of nonstructural system performance during earthquakes. The centerpiece of this effort involved shake table testing a full-scale five-story reinforced concrete building furnished with a broad variety of nonstructural components and systems (NCSs) including complete and opera...

Integrated structural health monitoring and damage prognosis (SHM-DP) methodologies, coupled with sensor-based nondestructive evaluation (NDE) techniques, are becoming increasingly important for the near-real-time condition assessment (i.e., SHM) and future performance predictions (i.e., DP) of aging mechanical systems, civil structures, and infras...

Seismic isolation provides a potentially promising strategy to mitigate the seismic risk to California High-speed Rail (CHSR) bridge structures. Notably, a proper selection of the seismic isolator properties must be carried out to strike a trade-off between the beneficial and detrimental effects of seismic isolation while accounting for the uncerta...

This paper presents the identification of modal properties of a full-scale five-story reinforced concrete building fully outfitted with nonstructural components and systems (NCSs) tested on the NEES-UCSD shake table. The fixed base building is subjected to a sequence of earthquake motions selected to progressively damage the structure and NCSs. Bet...