Strategy Analysis

1. Strategy Analysis

2. Strategy Analysis Strategy analysis is concerned with the analysis of entire road networks to determine funding needs and/or to predict future performance under budget constraints Objectives: • Determine budget allocations for road maintenance and improvement • Prepare for work programmes • Determine long term network performance • Assess impact on road users

3. Procedure • Categorise road network into matrix cells • Define representative traffic volume and loading • Define maintenance and improvement standards • Specify budget constraints • Model pavement deterioration for each matrix cell • Apply maintenance and improvement standards • Calculate road user benefits • Select maintenance standards which optimise user benefits

4. Road Network Matrix • Categorise road network into matrix • Road Class: Primary, Secondary, Tertiary • Pavements: Rigid, Paved, Gravel • Relative strength: Good, Fair, Poor • Condition: Good, Fair, Poor • Traffic: High, Medium, Low • Determine road length in each matrix cell • Record regional distribution

5. Representative traffic • Primary roads: Flexible pavements • High: > 10,000 vpd; (1.0m ESA/lane/year) • Med.: 5,000 ~ 9,999; (0.4m ESA/lane/year) • Low: < 5,000; (0.1m ESA/lane/year) • Primary roads: Gravel pavements • High: > 1,000 • Med.: 250 ~ 999 • Low: < 250

6. Road Network Matrix Length of Roads (km) Flexible Pavement Traffic High Med. Low Gravel Pavement Traffic High Med. Low Cond. Road Class G F P 76 283 307 485 762 561 911 420 321 686 452 703 855 904 1961 1905 2432 4321 National G F P Regional G F P Feeder

7. Bituminous Pavements • Routine Maintenance standards • Patch all potholes • Edge repairs • Fixed costs for drainage, safety, etc. • Periodic Maintenance standards • Overlay at Roughness > 5.5 IRI • Resurface at Surface damage > 30% • Improvement standards • Widen when V/C ratio > 1.2

8. Gravel Roads • Routine Maintenance standards • Spot regravelling (gravel patching) • Fixed costs for drainage, safety, etc. • Periodic Maintenance standards • Grading scheduled 2/year • Regravel when gravel loss > 100mm • Improvement standards • Upgrade to flexible pavement at ADT > 250

9. Budget Constraints & Optimisation • Recurrent budget • Routine maintenance • Top sliced from specified budget • Capital budget • New construction, upgrading, rehabilitation, etc. • Multi-year limit • Optimisation methods • Maximise NPV • Maximise network condition improvement • Minimise cost for target network condition

10. Pavement Deterioration and Maintenance Condition Reconstruct Overlay Traffic / Time

11. Maintenance and improvement costs • Routine and recurrent maintenance costs • Budget MUST be sufficient otherwise re-specify • Periodic maintenance costs • For specified alternatives • Improvement costs • For specified alternatives

12. Calculate road user benefits • vehicle operating cost savings • fuel, parts, tyres, depreciation, etc • travel time savings • reduction in accidents • pavement preservation

13. Determine optimum standards • Select optimum maintenance standards for each matrix cell under specified budget constraints • Calculate total routine, recurrent and periodic maintenance costs for each cell • Summarise total maintenance requirements for whole network

14. Total network needs Maintenance Costs ($m) Flexible Pavement Traffic High Med. Low Gravel Pavement Traffic High Med. Low Road Class Cond. G F P 6 3 0.7 15 13 4 31 22 11 1.6 0.4 0.3 9 4.4 1.1 19.6 14.2 9.5 National G F P Regional G F P Feeder

15. Budget Summary Maintenance Budget ($m) Primary Roads Flexible Gravel Secondary Roads Flexible Gravel Region 34.5 21.8 North 45.9 18.7 East 34.6 13.5 24.9 11.8 South 52.1 21.0 45.0 21.8 27.2 20.4 19.5 12.3 West

16. Budget Allocation • Routine maintenance needs based on road lengths under each category of roads • Recurrent maintenance needs based on pavement surface condition • Periodic maintenance needs based on economic indicators • Improvement needs based on economic indicators