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InRisk started in 2006 as a research project related to Infrastructure Risk. The project was funded by a Strategic Project Grant (STPGP 336498-06) from NSERC. The InRisk website has evolved into a collection of engineering tools that are maintained and coordinated by Terje Haukaas at the Department of Civil Engineering at the University of British Columbia in Vancouver, Canada. Please note that the notes and software programs that are posted on this website are revised without notice and they are provided "as is" without warranty of any kind. You are invited to submit suggestions and questions to terje@civil.ubc.ca.
The vision behind the InRisk Toolbox is to promote an engineering paradigm that is based on solid understanding of mechanics, comprehensive modelling of uncertainties, and strong focus on rational, transparent, and broad-based decision-making. Seminars on these topics are organized weekly and everyone are welcome to attend. Each seminar includes a presentation and a follow-up discussion. Coffee and cookies are served. Information about past and future seminars is provided below:
DATE: Wednesday, February 15, 2012
SPEAKERS: All Members of the Research Group
TITLE: Comparison of Our Modelling Efforts and the Probabilistic Model Code of the Joint Committee on Structural Safety
DATE: Wednesday, February 8, 2012
SPEAKER: Xinlei Huang
TITLE: Wood-frame Diaphragm Model
ABSTRACT: This presentation is a progress report on the research on “In-plane stiffness of wood-frame diaphragms.” The research to-date includes both numerical and experimental efforts, and results from both will be presented. Currently, work is carried out to calibrate the detailed numerical model for wood-frame diaphragms with various aspect ratios and orientations. Challenges and possible future directions of the study will also be discussed.
DATE: Wednesday, February 1, 2012
SPEAKER: Wellison Gomes
TITLE: Risk and Optimization: Hybrid Algorithms and Modelling of Random Corrosion Processes
ABSTRACT: This presentation will focus on two main subjects. The first is the development of hybrid algorithms for global structural optimization and the second is the representation of corrosion processes by polynomial chaos expansions. Two hybrid auto-regulated optimization algorithms are discussed, which combines two proposed variations of particle swarm optimization (PSO) with the modified Powell algorithm. The algorithms are applied to the solution of seven test problems. They are shown to out-perform nine out of ten algorithms from the literature. Subsequently, polynomial chaos expansions are utilized to represent the random time-evolution of metal corrosion growth in marine environments. This model is employed in reliability analysis of structures subject to marine corrosion. A future goal of the ongoing research is to carry out risk-based optimization, involving inspection, maintenance, and stochastic corrosion models.
DATE: Wednesday, January 25, 2012
SPEAKER: Sepideh Ashtari
TITLE: A Review of the Literature on In-plane Stiffness of CLT Panels
ABSTRACT: Previous studies on the subject of in-plane stiffness of CLT panels is reviewed and discussed. A comparison is made between the approaches utilized so far, and the method adopted in ongoing research.
DATE: Wednesday, January 18, 2018
SPEAKER: Terje Haukaas
TITLE: Research Directions in Probabilistic Modelling and Analysis
DATE: Tuesday, November 29, 2011
SPEAKER: Terje Haukaas
TITLE: The Art & Science of Engineering Modelling
DATE: Tuesday, November 22, 2011
SPEAKER: Terje Haukaas
TITLE: How to Write a Paper
DATE: Tuesday, November 15, 2011
SPEAKER: Abbas Javaherian
TITLE: Performance-based Earthquake Engineering: A Comparison of Two Approaches
DATE: Tuesday, November 8, 2011
SPEAKER: Sepideh Ashtari
TITLE: Producing In-Plane Load-Displacement Curves for Connected CLT-Panels Using ANSYS
ABSTRACT: The main objective of this presentation is to illustrate the generation of in-plane load-displacement curves (push-over curves) for connected CLT panels. These curves will subsequently be utilized to obtain in-plane stiffness values and in-plane behaviour of CLT diaphragms. In order to achieve that, a number of panel configurations will be modelled in ANSYS. Linear and nonlinear static analyses are carried out to get the displacement values for the applied load. This presentation discusses the methodology of producing aforementioned curves and examines related future work.
DATE: Tuesday, November 1, 2011
SPEAKER: Xinlei Huang
TITLE: Modelling the Hysteretic Behaviour of Nail Connections in Wood Construction
ABSTRACT: Panel-frame nail connections are widely used in light-frame wood construction in North America. These connections contribute greatly to structural redundancy, loading sharing, ductility and energy dissipation in buildings subjected to seismic loads. In this presentation, a brief introduction to the finite element model, HYST, which is used for the study of the hysteretic behaviour of panel-frame nail connections, will be given. In this model, the nail shank is modelled by an elasto-plastic beam element and the compression behaviour of the wood medium is modelled as continuous nonlinear springs smeared along the nail length. As a result, the embedment properties of wood medium, not easily obtained from direct testing, can be characterized by calibrating the model using either a load-slip curve from monotonic loading or backbone curve from cyclic loading.
DATE: Tuesday, October 25, 2011
SPEAKER: Mojtaba Mahsuli
TITLE: Adaptive Model Refinement and Risk Mitigation for Infrastructure Exposed to Multiple Hazards
ABSTRACT: The motivation for this presentation is the need to prioritize the allocation of resources to civil infrastructure subjected to multiple hazards. Three different but complementary questions are asked and addressed in ongoing research: 1) Which infrastructure components should be prioritized for seismic retrofit to mitigate seismic risk? 2) Which infrastructure components should be subjected to detailed modelling to reduce the epistemic uncertainty in order to improve the quality of the risk analysis? 3) Which models in the library should be prioritized in near-term research to reduce the epistemic uncertainty to improve the quality of future risk analyses? To answer these questions the sensitivity of the reliability index with respect to three parameters is studied: 1) Retrofit cost, 2) epistemic model standard deviation, and 3) modelling cost.
DATE: Tuesday, October 18, 2011
SPEAKER: Terje Haukaas
TITLE: Reliability-based Design Optimization
ABSTRACT: The motivation for this presentation is our desire to make good decisions under conditions of uncertainty. In particular, the allocation of limited resources to optimally mitigate risk to civil infrastructure is the underlying problem. This presentation starts by covering the basic concepts of deterministic optimization and classical reliability-based design optimization (RBDO). Next, the application of RBDO in contemporary performance-based seismic engineering is discussed. The formulation of proper objective functions and constraints is specifically addressed. Finally, the presentation includes recent problems and developments; particularly the use of RBDO in the context of continuous seismic loss curves and the utilization of state-of-the-art optimization techniques from the financial sector.
DATE: Tuesday, October 11, 2011
SPEAKER: Abbas Javaherian
TITLE: An Introduction to Logistic Regression
ABSTRACT: The main objective of this presentation is to introduce the concepts and application of logistic regression. Logistic regression has been devised to predict the probability of occurrence of discrete events, formulated as a function of regressors. The practical development of models by logistic regression is studied in this presentation. In particular, two methods of developing of logistic regression models will be examined and discussed. Furthermore, an example will be presented to demonstrate the methods and their application. The application of logistic regression to real engineering problems, particularly in earthquake engineering, remains an important motivation for the next steps of this research.
DATE: Tuesday, October 4, 2011
SPEAKER: Sepideh Ashtari
TITLE: Evaluating the In-plane Stiffness of CLT Floors: Preliminary Studies
ABSTRACT: This presentation is a progress report on the ongoing research on “Evaluating the In-plane Stiffness of CLT floors”. The main objective of this research is to characterize the in-plane behavior of connected CLT panels, performing as diaphragms. In the next step, the influence of in-plane stiffness on distribution of lateral forces to the shearwalls will be studied. In this presentation, preliminary studies done so far will be presented and discussed.
DATE: Tuesday, September 27, 2011
SPEAKER: Xinlei Huang
TITLE: Detailed Numerical Model for Wood-Frame Diaphragms
ABSTRACT: Floor and roof diaphragms are important components of wood-frame buildings. They are used to resist and transfer the lateral forces produced by wind or earthquakes. The current lack of an accurate methods to predict their in-plane diaphragm stiffness prevents designers from knowing exactly how much stiffness to expect from any given design. Adequate diaphragm stiffness is required in order to decide the distribution of lateral loads among the supporting shear walls. As the first step of this research, a detailed finite element model for analyzing wood-frame diaphragm is presented. The model is established using a finite element program named FLOOR2D and the resulting cyclic load-displacement results are compared with test data obtained elsewhere. Calibrations are carried out to minimize discrepancies between the numerical model and the test results. As a result, the numerical model is available to simulate diaphragm cases for which test results are unavailable.
DATE: Tuesday, September 20, 2011
SPEAKER: Thomas Tannert
TITLE: Probabilistic capacity prediction of timber joints under brittle failure modes
ABSTRACT: The presentation introduces to a probabilistic design method for timber joints under brittle failure modes. To predict the capacity of timber joints is difficult due to the anisotropic and brittle nature of the material, the complex stress distribution as well as the uncertainties regarding the associated material resistance. The method considers the statistical variation and the size effect in the strength of timber using a Weibull statistical function and presents an explanation for the increased resistance of local zones subjected to stress peaks. The method was implemented into a practical numerical post processing routine. The results were benchmarked by a direct comparison with experiments on: (i) adhesively bonded joints; (ii) rounded dovetail joints; and (iii) welded wood joints. The statistical distributions of the material strengths were obtained with small scale specimen tests: the problem of using different test configurations is discussed. The presentation furthermore discusses how the probabilistic method has to be formulated to predict characteristic values of joint capacities, and possible future enhancements and extensions.
DATE: Tuesday, September 13, 2011
SPEAKER: Ricardo Foschi
TITLE: Experimental test results and adjustment of a damage accumulation model for load duration in wood
DATE: Tuesday, September 6, 2011
SPEAKER: Laura Quiroz
TITLE: Probabilistic Assessment of Damage States using Dynamic Response Parameters
ABSTRACT: An application of Bayes' inference rule to evaluate the probability of damage in structures, using measured modal parameters and a set of possible damage states is presented. The main objective is to identify the most likely damage scenario characterized in terms of damage indicators. These indicators are associated with the stiffness contribution from each substructure in the finite element model. Each predefined damage state is associated with an initial or prior probability. In order to calculate its updated or posterior probability, given a set of measurements, a Bayesian updating is implemented. In this methodology, the prior probability is updated by means of the likelihood functions, which represent the probability density function of a modal parameter given a damage state. The discussion considers the type of measurements and the number of repeated measurements that are required to achieve a substantial confidence as to the presence of a particular damage scenario.
DATE: Tuesday, August 30, 2011
SPEAKER: Mojtaba Mahsuli
TITLE: A New Approach for Regional Seismic Risk Assessment: Probabilistic Models and Reliability Analysis
ABSTRACT: A library of probabilistic models for seismic risk analysis is presented. New models are developed for epicenter location, regional loss, and building-by-building damage and repair cost. These models are implemented alongside a host of other models in Rt. This program is tailored for reliability analysis with multiple probabilistic models. The methodology represents a different way of estimating seismic risk, and the “modularized” nature of the approach is emphasized. Individual models are readily updated or replaced without affecting the other models. The models and the software are demonstrated by computing seismic loss probabilities for the Vancouver metropolitan region in Canada. The analysis is comprehensive and comprises 567 random variables and 3,232 model objects. Two analysis techniques are explored, one based on sampling analysis and the other based on the first-order reliability method in conjunction with load coincidence analysis. The results include the “loss curve,” which exposes the probability that different loss values will be exceeded in the time period under consideration.
DATE: Tuesday, August 23, 2011
SPEAKER: Terje Haukaas
TITLE: Dealing with Uncertainty: From Laplace’s Demon to Black Swans
ABSTRACT: Uncertainty is an unavoidable aspect of engineering. Engineers must make decisions about the suitability of designs although the knowledge about models and parameters is imperfect. In structural engineering practice, design codes come to rescue. The codes provide information and criteria that essentially removes the uncertainty from the engineer’s view. This presentation re-examines the presence of uncertainty in a broad context that includes different engineering fields. A taxonomy of uncertainty is presented together with measures of predictability. The material is framed by two drastic ideas mentioned in the title; one says that everything could be predicted, while the other says that predictions, even probabilistic predictions, are associated with severe limitations.
Tuesday, April 19, 2011
Terje Haukaas
Revisiting the InRisk modelling mantra, with a new look at software and web pages
Tuesday, March 8, 2011
Ricardo Foschi
Probabilistic analysis of bridge piers subject to vessel collision
Tuesday, March 1, 2011
Terje Haukaas
Seismic design procedures
Tuesday, February 22, 2011
Ricardo Foschi
Reliability analysis of wooden bridge decks
Tuesday, February 15, 2011
Terje Haukaas
The ideal reliability course
Friday, December 3, 2010
Mojbata Mahsuli
Multi-hazard reliability analysis
Friday, November 19, 2010
Terje Haukaas
Objectives and trends in current reliability research
Friday, October 22, 2010
Shahrzad Talachian
Probabilistic modelling by Bayesian updating
Friday, October 15, 2010
Laura Quiroz
Probabilistic damage state evaluation using dynamic response parameters
Friday, October 8, 2010
Terje Haukaas
The role of probabilistic methods in simplified seismic design procedures
Friday, September 24, 2010
Mojtaba Mahsuli
Reliability analysis with multiple probabilistic models
Friday, May 14, 2010
Laura Quiroz
A discussion of probabilistic seismic hazard analysis for the Pacific Northwest
Friday, May 7, 2010
Erwan Harrouch
Subset simulation: a sampling analysis option for reliability analysis
Thursday, April 8, 2010
Tony Yang
An implementation of performance-based earthquake engineering
Thursday, March 25, 2010
Terje Haukaas
a) Bayesian Networks, b) Library of predictive probabilistic models
Thursday, March 18, 2010
Karthick Pathman
Metro Vancouver's Post-Earthquake Transportation System: Land-Use Planning Implications
Thursday, March 11, 2010
Mojtaba Mahsuli
Loss Curve for Region with Scarce Information
Thursday, February 4, 2010
Tony Yang and Terje Haukaas
Projects and Approaches to Address Earthquake Risk
Thursday, January 28, 2010
Anne-Marie Langlois
Influence of Corrosion on the Structural Reliability of RC Bridges: Case Study
Thursday, January 14, 2010
Terje Haukaas
Status Report and Research Coordination
Thursday, December 17, 2009
Laura Quiroz
Reliability Analysis Using Neural Networks as Substitute for Structural Response
Thursday, December 10, 2009
Terje Haukaas
Probabilistic Models from Data: Examples and New Options in Rt
Thursday, December 3, 2009
Shahrzad Talachian
Preliminary Probabilistic Damage Models by Bayesian Updating
Thursday, November 26, 2009
Mojtaba Mahsuli
Probabilistic Models for Buildings and Hazards: Tools for Next-Generation of Structural Engineering
Thursday, November 19, 2009
Majid Baradaran Shoraka
System-level Acceptance Criteria for Seismic Assessments of pre-1970 Reinforced Concrete Buildings
Thursday, November 12, 2009
Karthick Pathman
The Final Stages: Prospects for Research Exposure, Dissemination, and Publication
Thursday, November 5, 2009
Edwin Guerra
Probabilistic Models for Environmental Impact
Thursday, October 29, 2009
Terje Haukaas
Probabilistic Models: Formulation, Calibration, Implementation
Thursday, October 8, 2009
Göran Fernlund, Materials Engineering, UBC
Reduction of Risk and Uncertainty in Composites Processing using Process Modelling and Bayesian Statistics
Thursday, October 1, 2009
Ricardo Foschi
A practical application of performance-based design to structural insulated panels
Thursday, September 17, 2009
Terje Haukaas
Development of Probabilistic Models
Thursday, September 3, 2009
Mojtaba Mahsuli and Karthick Pathman
Reliability analysis of the Metro Vancouver transportation network using Rt and EMME
Thursday, August 13, 2009
Mojtaba Mahsuli
Data gathering and modelling for regional risk analysis of UBC and Vancouver
Thursday, August 4, 2009
Terje Haukaas
Some International Projects and Research Directions on Infrastructure Risk
Friday, May 22, 2009
One-day Seminar on Infrastructure Risk (CEME 2003, UBC-Vancouver)
Terje Haukaas: Infrastructure Risk
Mojtaba Mahsuli: Software Rt: Reliability tools
Karthick Pathman: Examining Earthquake-Related Transportation Disruption in Metro Vancouver
Edwin Guerra: Sustainability in Engineering: Environmental and Resource Impacts
Alejandro Bohl: Probabilistic Performance-based Engineering
Shahrzad Talachian: Probabilistic Damage and Loss Models by Bayesian Updating
Majid Baradarn Shoraka: System-Level Acceptance Criteria for Seismic Assessments of Reinforced Concrete Buildings
Thursday, April 2, 2009
Terje Haukaas
Examples of Performance-based Engineering and Regional Risk Analysis
Thursday, March 26, 2009
Shahrzad Talachian
Probabilistic Damage and Loss Models by Bayesian Updating
Thursday, March 19, 2009
Majid Baradaran Shoraka
System-Level Acceptance Criteria for Seismic Assessments of Pre-1970 Reinforced Concrete Buildings
Thursday, March 12, 2009
Karthick Pathman
Examining Earthquake-Related Transportation Disruption in Metro Vancouver
Thursday, March 5, 2009
Mojtaba Mahsuli
Rt Revealed
Thursday, February 26, 2009
Alejandro Bohl
Probabilistic Performance-based Earthquake Engineering
Thursday, February 12, 2009
Edwin Guerra
Big Picture Thinking: Sustainability and Decision-Making
Thursday, February 5, 2009
Terje Haukaas
Implementation of Probabilistic [Earthquake Hazard] Models in Rt
Thursday, January 12, 2009
Mojtaba Mahsuli
Rt: Reliability tools
Thursday, September 25, 2008
Majid Baradaran Shoraka
ATC-63 (FEMA P695) Report - Part II
Monday, September 18, 2008
Alejandro Bohl
Fragility curves in unified reliability analysis
Thursday, September 11, 2008
Majid Baradaran Shoraka
ATC-63 (FEMA P695) Report: Quantification of Building System Performance and Response Parameters
Monday, March 3, 2008
Alejandro Bohl and Terje Haukaas
Using fragility curves with FORM
Monday, February 4, 2008
Smitha D. Koduru
Ground Motions: Scaled or Simulated?
Monday, January 28, 2008
Karthick Pathman
Modeling Transportation System Performance under Multiple Hazards
Monday, January 21, 2008
Majid Baradaran Shoraka
Updating of Reliability Results by means of Experimental Tests
Monday, November 5, 2007
Terje Haukaas
A User’s Guide for Risk-based Decision Making in Engineering
Monday, October 29, 2007
Majid Baradaran Shoraka
Overview and Development of Hybrid Testing
Monday, October 22, 2007
Mojtaba Mahsuli & Terje Haukaas
Presentation and discussion of the InRisk website with an in-depth look at user-friendly engineering software
Monday, October 15, 2007
Smitha Koduru
Feasibility of FORM in performance-based engineering applications
Monday, October 1, 2007
Gaurav Sharma
Failure statistics and reliability analysis for mining equipment
Monday, September 24, 2007
Matthew Benjamin
Models and methodologies for probabilistic performance-based engineering
Monday, September 17, 2007
Ricardo Foschi
A new damage measure for performance-based engineering
Monday, September 10, 2007
Terje Haukaas, Ricardo Foschi, and Matthew Benjamin
Damage measures for (probabilistic) performance-based engineering
Wednesday, September 5, 2007
Terje Haukaas
Activities in the "Reliability Group" at UBC, including strategic research on infrastructure risk
Tuesday, April 17, 2007
Soheil Yavari
Post-Earthquake Functionality of Health Care Facilities
Tuesday, April 10, 2007
Terje Haukaas
Damage Predictions for Reliability Applications
Tuesday, March 20, 2007
Terje Haukaas
Performance-based earthquake engineering: 1) Contrasting the "unified reliability analysis" with the "PEER procedure" and 2) Novel design optimization based on unified reliability analysis
Tuesday, March 13, 2007
Vincent Dubourg
Implementation of a reliability-based design optimization algorithm in FERUM
Tuesday, March 6, 2007
Ken Elwood
The ATC-58 project; trends in performance-based earthquake engineering
Tuesday, February 13, 2007
Smitha Koduru
Probabilistic Models for Earthquake Ground Motion in Vancouver
Tuesday, February 6, 2007
Armin Bebamzadeh
Second-order Response Sensitivities: Feasibility, Computational Cost, Applications
Tuesday, January 30, 2007
Goran Fernlund
How do we quantify our confidence in model predictions?
Tuesday, January 23, 2007
Matthew Benjamin
Probabilistic Models for Structural Deterioration
Tuesday, January 16, 2007
Douglas Beaton
Stock Portfolio Optimization
Tuesday, January 9, 2007
Terje Haukaas
Risk and reliability methods in financial applications
Thursday, January 4, 2007
Terje Haukaas
Objectives and strategies for the new strategic research on infrastructure risk
Wednesday, November 29, 2006
Maik Gehloff
Visualizations and Visions in future engineering software
Wednesday, November 22, 2006
Terje Haukaas
User interfaces for risk and reliability software
Wednesday, November 15, 2006
Armin Bebamzadeh
Second-order sensitivities by the Direct Differentiation Method
Wednesday, November 8, 2006
Ricardo Foschi
Practical application of performance-based design to built-up composite panels
Wednesday, November 1, 2006
Terje Haukaas
The future of risk, reliability, and decision making software
Wednesday, October 25, 2006
Smitha Koduru
What reliability can do for you
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