# Presentation: 290359

## Pontis Applications and Modelsprepared by:Cambridge Systematics, Inc. 

## Outline

**Overview of the Pontis Modeling Approach**
**Special Topics in Modeling**
**Triggering Actions with Smart Flags**
**Definition of MR&R versus Improvements**
**Removing Structures from Consideration**
**Pontis 4.0 Update**

## Pontis Modeling Approach

## Modeling Approach Overview

**The Pontis® BMS use an integrated set of models to recommend bridge preservation and improvements**
**Preservation Model**
**Optimization model used to recommend the policy to follow for maintaining bridge elements in a state of good repair**
**A set of actions, or policy, is recommended for each element**
**Program Simulation Model**
**Simulation model used to recommend projects for each bridge over a specified period of time**
**Objective is to maximize benefit given a budget constraint**
**The preservation policy is an input to the simulation**

## Decomposition of a Structure in Pontis

***Decomposition of a Structure in Pontis***

## How Pontis Sees BridgesElements & Environments

**The concept of bridge elements is essential to Pontis**
**Elements may be decks, beams, arches, joints, etc...**
**AASHTO has defined a set of commonly recognized (CoRe) elements.  Agencies may define additional elements**
**A particular element may exist in one of four environments**
**Environments are generally used to describe different weather or operating conditions**

## How Pontis Sees BridgesStates & Actions

**Depending on the condition of an element, the element is assigned to one of up to five states**
**Lowest state is the best condition, highest is the worst**
**For each state, for a given element, there are up to three feasible maintenance actions that Pontis may recommend**
**Actions are more general than would be required for complete project specification**
**CoRe elements have pre-defined states and actions - agencies may define their own as well**

## Pontis Preservation Policy

**Pontis recommends the optimal maintenance policy,****or set of recommended actions for each state, for****each element-environment combination**
**Preservation models are built based****on expert opinion (elicitations)****and inspection history**
**Each element is****modeled independently**
**The preservation models****optimize based on discounted****long-term agency costs using****a Markovian decision model**

## Predicting Element Conditions

**Pontis generates a transition probability (TP) matrix for each element-environment combination**
**Specifies probability of transition to each state for each action, including do-nothing and do-something actions**
**Rows of the matrix are actions, columns are states**
**Built based on elicitations and inspection data**
**One can predict future conditions by multiplying TP matrix by the vector representing current conditions**
**Easiest to demonstrate this through a spreadsheet**

## Pontis Program Simulation

**Predicts bridge maintenance and improvement needs****over time**
**Recommends projects for individual bridges given a****program-level budget constraint**
**Uses:**
**Preservation policy**
**User-specified improvement policy and costs**
**User benefit models**
**Project scoping parameters**

## Program Simulation Steps

**Compile bridge data**
**Determine needs**
**Preservation needs are generated by applying the preservation policy to each element on the bridge**
**Improvement needs (widening, raising, strengthening) are generated based on the improvement policy**
**Apply project scoping parameters**
**Minimum project cost, etc. . .**
**Many new parameters and rules in Pontis 4.0**

## Program Simulation Steps (cont.)

**Generate the list of project alternatives**
**Sort the list of project alternatives**
**Select projects**
**With an unlimited budget, Pontis will do the project with the most benefit for each bridge - often a replacement**
**With a budget constraint, Pontis will pick projects to generate the most benefit with the available budget**
**Calculate impact of projects and roll forward bridge conditions**
**Repeat process for each year of the simulation**

## Modeling Changes in Pontis 4.0

**No changes to the preservation model**
**New alternatives for representing preservation benefits and sorting projects**
**Many new project scoping parameters to generate more realistic projects**
**Many new performance measures calculated by the simulation (e.g., sufficiency rating, HBRR eligibility)**
**Better treatment of user-defined projects**
**Many additional modeling and user interface improvements**

## Special Modeling Topics

## Special Topics  - Smart Flags

**By default, smart flags get ignored in the program simulation**
**New functionality has been added in Pontis 4.0 for specifying agency preservation policies**
**Can specify that a certain smart flag condition should trigger action on another element**
**Example: When the Soffit Smart Flag is in State 5, replace the deck if not in State 1**
**To use this functionality it is necessary to define actions and transition probabilities for smart flags**

## Special Topics - MR&R versus Improvements

**Users can specify that the simulation should include:**
**MR&R only**
**Improvements only**
**MR&R and improvements**
**MR&R and improvement needs both may trigger replacement**
**When improvements are excluded, Pontis will not evaluate the need for widening, raising or strengthening bridges**
**It is not possible to redefine what is MR&R and what is an improvement**

## Special Topics - Excluding Structures

**It is possible to exclude selected structures from consideration in the program simulation**
**In Pontis 4.0 structures with programmed work will generally be excluded by look ahead rules (don’t work on the bridge if a replacement in planned)**
**In Pontis 3.4/4.0 bridges can be excluded by:**
**Developing a structure list the excludes selected structures**
**A field can be used or added to indicate whether to exclude the structure**
**Run the program simulation for “bridges meeting filter criteria” only**

## Pontis 4.0 Update

## Pontis 4.0 Update

**Pontis 4.0 is in final acceptance testing**
**Release scheduled for Summer 2001**
**User Meeting scheduled for September**
**FY 2001-2002 activities**
**Finalize user, technical manuals**
**New training materials**
**Pontis 4.1 planned - Bridgeware integration release**

## Pontis 4.0 Inspection Enhancements

**Improved user interface**
**Improved support for English units**
**Support for inspector work candidates**
**Inspectors recommend work for the bridge**
**Can use Pontis actions, or other agency-defined actions**
**Recommendations are presented in project planning**
**Desktop enhancements**

## Inspection Module Interface

## Network Decision Enhancements

**New simulation rules added to improve match of models to agency practice**
**Improved treatment of user projects**
**New performance measures projected as part of the program simulation:****	**
**NBI Ratings**
**Sufficiency Rating**
**SD/FO Status**
**New Results Module**

## Results Module Interface

## Project Planning Enhancements

**Completely new interface replacing previous project planning and action log module**
**Powerful and intuitive tree view**
**Tools to manage, combine, organize projects**
**Incorporates user-defined projects, inspector candidate and Pontis candidate work**

## Project Planning Interface

## Bridge Analysis Enhancements

**New functionality to:**
**See all work planned or recommended for a bridge**
**Fine tune the work items**
**See the effects of performing selected items**
**Finalize work for the bridge**
**Supports bridge-by-bridge planning**
**Takes advantage of Pontis model approach, and Pontis recommendations**

## Bridge Analysis Interface

## Project Planning Interface	

**Graphical management of project information**
**Shows Pontis and inspector-generated bridge needs simultaneously**
**Multiple views of project information**
**by project, by bridge**
**Customizable presentations**
**Powerful query and selection features**
**Tracks projects through entire lifecycle**

## Database Enhancements	

**Eliminate unnecessary data redundancy**
**Improve element****history storage**
**Storing network and bridge****performance measures **
**Support for tracking****inspector work****recommendations**
**Use of float data****types for measurements**