1. Multi-Year Programming and Predictive Modelling
An Overview

2. Multi - Year Programming
The process of
applying maintenance interventions to
treatment lengths
across the network
over the life cycle of the pavement

3. Requirements for Multi-Year Programming
Data on road characteristics, condition, traffic etc. (RAMM)
Treatments, effects, costs and trigger levels
Prediction models for pavement deterioration
Prediction models for road user effects
Software to apply the models and prioritise alternative strategies

4. Selecting the Right Treatment and Applying it at the Right Time to
Optimise Life Cycle Costs
Predicting
What Treatments and When
EFFECTIVE LIFE
REPLACE
PROGRESSIVE ( ACCRUED )
COST OF FACILITY
CASH FLOW
OF ASSETS
CREATE
MAINTAIN
DISPOSAL
REFURBISH
100%
VALUE / COSTS
( REAL TERMS )

5. Definitions Treatments Strategy
A maintenance activity applied to a pavement
Strategy
A treatment and when it is applied
SCHEDULED - regular time intervals
RESPONSIVE - responds to condition

6. A Strategy is a series of Treatments

7. Predictive Modelling
A tool used by Asset Managers to assist in the determination of the timing of maintenance treatments over the life cycle of the Asset
Utilises a modelled rate of deterioration and economic benefits and costs to assess timing

8. Deterioration Management
EXCELLENT
ORIGINAL DECAY
OPTIMAL
CONDITION
BAND
ASSET
CONDITION
Maintenance
Treatments
OPTIMAL RENEWAL
STRATEGY
POOR
TIME

9. Treatments, Triggers and Resets
Decay in Condition
(DETERIORATION)
EXCELLENT
Condition
Improvement
(RESET)
ASSET
CONDITION
Minimum Acceptable Standard
(TRIGGER)
Treatment Applied
POOR
TIME

10. Treatment Generic Types
Strengthening
Reconstruction AC
Reconstruction ST
Thick Asphalt Overlay
Thick Granular Overlay
Smoothing
Thin Asphalt Overlay
Thin Granular Overlay
Rip and Replace ST
Rip and Remake AC
Mill and Replace AC
Resurfacing
Large Chip Resurfacing
Small Chip Resurfacing

11. Economic Considerations
There are three options utilised
Maximize Area under Curve
Minimize Total Transportation Cost
Maximize Saving in VOC

12. Area Under Curve (AUC) Composite Index Analysis Period Time Benefit
Strategy
Composite Index
Salvage
Do-nothing
Analysis Period
Time

13. Minimize Total Transportation Cost (TTC)
Optimum Maintenance
Total Transport Costs
COSTS
Road User Costs
Maintenance Costs
Construction Costs
MAINTENANCE LEVEL

14. Maximize Saving in VOC VOC Analysis Period Time Benefit Do-nothing
Strategy
Analysis Period
Time

15. Selection of Economic Analysis Method (example)
Objective Function
Const. Budget Poor Roads
Med. Budget Poor Roads
Adeq. Funding Good Roads
Objective Function
Area Under Curve
Total Transportation Costs
Vehicle Operating Costs

16. Selection of Strategies
The efficiency frontier is used in the selection of optimum strategies
Utilises the incremental benefit cost ratio to select optimum mix of strategies

17. Selection of Strategies (Efficiency Frontiers)
Benefits
Costs
IBC 2 3 4 5 B A

18. What we do to a road now is determined by:
The characteristics of the road
The traffic using it
The available funding
The performance standards to be applied in the future

19. Programme Level Analysis can tell us:
What budgets do we need to achieve a given set of performance standards?
What treatments will be applied, when and where to meet those standards?
What treatments should be applied, when and where if budgets are less than ideal?
What will be the performance level of the network with constrained budgets?

20. Types of Analysis Performance Based Analysis
Defines the budget required to meet a performance standard (Level of Service)
Economic Analysis
Defines a maintenance strategy designed to fit a fixed budget

21. Economic Analysis
Defines the optimum maintenance strategy for each road section given a set of budgets for the road network
Requires prediction of costs and benefits for alternative strategies for each road section
Requires an optimisation procedure with an objective function e.g. minimise total transport costs
Typically used by a road agency when contracting works on an annual basis

22. Performance Standards Analysis
Defines budgets, treatment types and timing to meet a given set of performance standards
Not necessary to consider road user costs
Typically used by a road agency to support funding applications or contractors bidding for performance based contracts
Objective of the analysis is to minimise maintenance costs while meeting the performance standards

23. Performance Standards can be defined in many ways:
Average service levels for the whole network or broad categories of road
Minimum service levels for categories of road
Trigger levels for specific treatment types
The way the standards are specified will affect the analysis setup

24. Data requirements Road Referencing Data Traffic Characteristics
Pavement Properties
Pavement History
Road Condition
Strength Data

25. Budget Constraints
Short term budget constraints may imply increased spending in the future
Important to define long term performance standards that are affordable
Refine triggers in a Performance Standards analysis to fit budgets and apply these triggers in Economic analysis as long term standards

26. dTIMS Pavement Models
Have mainly implemented modified HDM-III for Phase I
Predicting Cracking
Ravelling (Flushing)
Potholing
Roughness
Texture
SCRIM

27. Pavement Strength
Can be one of the more important pavement deterioration modelling parameters
Analysis uses SNP: Structural Number of the Pavement
Methodologies to assess SNP are included in the project
A range of options is available with varying data complexity needs

28. Available Methods FWD with Layer Thicknesses
FWD without Layer Thicknesses
CBR Layers
Benkleman Beam
ARRB Pavement Capacity
Typical Pavement Designs