Pontis Modeling Approach Overview

1. Pontis ModelingApproach Overview

2. Outline What is Pontis? Developing a preservationpolicy in Pontis Simulating bridge conditions New modeling features in Pontis Improved deterioration model updating Performance targeting for the long-term preservation model Other improvements Information resources

3. What is Pontis? Windows-based bridge management system (BMS) with functionality for: Recording bridge inventory and inspection data Developing an optimal preservation policy Simulating conditions and generating work candidates Developing a bridge program Used by over 45 agencies throughout the U.S. and abroad Originally developed for the FHWA, now owned by AASHTO with Cambridge Systematics as AASHTO�s contactor One component of AASHTO�s BRIDGEWare Suite

4. What is Pontis?Key Features of Pontis Representation of a bridge as a set of structural elements Recommendation of an optimal preservation policy Extensive functionality for program simulation Recommends preservation and improvements Considers agency and user costs Predicts a broad range of performance measures, with support from the FHWA NBI Translator Support for an Oracle, Sybase or SQL Server Sybase Extensive functionality for customization

5. What is Pontis?Bridge Management Process Supported by Pontis

6. Developing a Preservation Policy in PontisUse of Elements in Pontis A bridge in Pontis is represented as a set of structural elements AASHTO defines a set of Commonly Recognized (CoRe) elements, including descriptions of the element and condition states for each Agencies may use the CoRe elements or define their own For each element the user specifies Feasible preservation actions for each state Action costs and deterioration rates (expressed using transition probabilities) for each state Bridges are inspected at the element level

7. Development of a Preservation Policy in PontisElement-Level Representation of a Bridge

8. Developing a Preservation Policy in PontisModeling Approach Pontis recommends the optimal maintenance policy,or set of recommended actions for each state, foreach element-environment combination Preservation models are built basedon expert opinion (elicitations)and inspection history Each element ismodeled independently The preservation modelsoptimize based on discountedlong-term agency costs usinga Markovian decision model

9. Simulating Bridge ConditionsPurpose of a Program Simulation Pontis performs program simulations to Determine current and future needs Predict future performance Develop work recommendations Pontis can be used to determine Conditions predicted based on a given budget Budget needed to achieve a target Given inspector and Pontis recommendations, an agency can use the system to develop its bridge plan

10. Simulating Bridge ConditionsInputs to a Program Simulation Bridge inspection data Preservation policy (generated by Pontis) Functional improvement policy and costs Budget Agency business process rules Planned projects Additional simulation parameters

11. Simulating Bridge ConditionsSimulation Results Predicted conditions (network and bridge-level) Needs and predicted work Benefits of meeting needs andperforming predicted work Element conditions Health index NBI condition ratings Sufficiency Rating SD/FO status Bridge-level workrecommendations

12. New Modeling FeaturesImproved Deterioration Model Updating Deterioration models can be build based on expert opinion (elicitations) and inspection history Recent improvements to the model updating process Better algorithm for using inspection history in the update process Option to specify whatbridges� history to usefor model updating Ability to rebuild historyor use prior history whenperforming successivemodel updates

13. New Modeling FeaturesPerformance Targeting in the Preservation Model The long-term preservation model is used to specify optimal steady-state conditions Steady-state conditions would result from following a specified policy over a period of many years Pontis solves the long-term optimization model to determine what the annual cost would be to remain in the optimal steady-state condition With Pontis 4.4 a user can add performance targets to the long-term optimization Targets are specified in terms of Health Index Provides long-term steady state funding requirements to achieve a specified performance target

14. New Modeling FeaturesPerformance Targeting Applications Determining the cost of meeting agency-definedperformance targets Quantifying thecosts of sub-optimalbridge conditions Determining long-termminimum preservationfunding requirements Improvedunderstanding ofthe Pontis-generatedpreservation policy

15. New Modeling FeaturesOther Improvements Ability to specify bridges exempted from the agency�s functional improvement policy (e.g., historic bridges) Program simulation horizon of up to 99 years Flexibility for entering program simulation inputs in English or metric units Capability for specifying when a bridge should be removed from the inventory at some future point

16. Information Resources Web resources FHWA: http://www.fhwa.dot.gov/infrastructure/asstmgmt/manag.htm AASHTO: http://www.transportation.org/aashto/home.nsf/FrontPage Pontis software support: http://aashtoware.camsys.com Documentation Pontis User�s Manual Pontis Technical Manual Referentia for Pontis Training CD