1. Current Status of Japanese Road Bridges and Future Perspective
HIROAKI TERAMOTO
Ministry of Land, Infrastructure and Transport

4. Numbers of bridges by type of material (only bridges over 15m)

5. Distribution of bridges for completion year

6. Road Work Budget in JAPAN (2005)
Maintenance
& repair
￡1.44 billion
National Road Projects
￡11.47 billion (22.5%)
Construction, operation & others
Total investment
in road projects in JAPAN
￡50.96 billion (100%)
Projects undertaken by local governments
￡30.65 billion (60.1%)
Operation of Toll Roads
￡　8.84　billion
(17.4%)

7. National Highways Maintenance Budget(2005)
Repair work for Structure: (35%)
Repair of bridges and tunnels, Pavement
Daily Maintenance : (13%)
Road cleaning, Planting etc.
Maintenance
￡1.10 Billion
( 77 %)
Road Patrol : (9%)
Minor Repair Work : (18%)
Repair for retaining walls, drains etc.
Maintenance and Repair (￡1.44Billion)
Others : (2 %)
Emergency restoration for disasters
Improvement
￡0.33 Billion
(23%)
Countermeasures for earthquakes : (11%)
Reinforcing of substructures, Prevention for bridge fall
Disaster prevention : (12%)
Slope protection

8. Type of Inspection in JAPAN
Usual Inspection
Periodic Inspection
Special Inspection
（Salt Damage, ASR, Fatigue…）
Disaster Inspection
( Earthquake, typhoon…)

9. Damage of Road Bridges in JAPAN (the Results of Periodic Inspection)

10. Fatigue cracks on girder

11. Breaking of reinforcing bars by ASR
Damaged gas pressure weld point (main reinforcements)
Breaking at corner of the shear reinforcement

12. Dropping-off of concrete of RC Slab

13. Causes for bridge reconstruction (National highways and prefectural roads)  
Steel bridges PC bridges
Cracking and peeling of concrete
(Chloride attack)
16.7%
Damage of RC slab
33.3%
Cracking and
peeling of
concrete
50.0%
The　others 6.8%
Damage of
RC slab
67.2%
Corrosion of　steel member
26.0%

14. Chloride damage of PC girder

15. Air Salt in Winter (climate)
Tsukuba
Narita Airport
Tokyo
Kansai Airport
Osaka
Kyoto
Tokyo to Tsukuba 50km
Tokyo to Osaka 560km N S
Monsoon
Rome
latitude

16. Maintenance cost for a deteriorated concrete bridge

17. Prediction by the results of Inspection
(example) Chloride Damage in concrete
at cover depth
If Cl- exceeds 1.2kg/m3 or will exceed 1.2kg/m3 within next 10 years,
Planning of Repair should be undertaken.

18. Relation between type of repairs and cost
Case 1：Preventive repair (Minimizing Life Cycle Cost)
Case 2：Repair at the repairable limit state T₁ T₂ T₃
year
Evaluation period
Cost
Case 1
Case 2
Soundness
Small
repair
Large

19. Asset Management Flow of Bridges Maintenance
Bridge Dimensions
Inspection
Properties of structure
Database
Prediction of Future Soundness
Comparison of Type of Measures,Minimizing of Life Cycle Cost,　Budget Restriction / Social Situation
Investment Analyzing
Risk based Prioritization
Decision of Management Plan
Execution of Measures or Maintenance
Evaluation of Present Soundness

22. SUMMARY ( Needs in JAPAN)
(1) Inspection of Local Road Bridges
( needs to make a New Act/Law)
(2) Improve the Forecast Model of Deterioration
( the Methods of Life Cycle Cost Analysis )
(3) Develop Non-Destructive Test Techniques
(4) Develop Prioritization System of Maintenance
(5) Make the Market of Maintenance-Works
more Attractive and Profitable

23. Thank you for your attention!
END