1. 1 Challenge the future Onderhouden of Nieuwbouwen Prof Han Vrijling/ir drs Jules Verlaan

2. 2 Challenge the future Contents Theory of Maintenance Maintenance in Port Engineering Life cycle cost Economic life cycle approach Life cycle approach to systems Conclusions

3. 3 Challenge the future Mechanical Engineering Maintenance Inspection Repair Strategies Corrective Failure Repair Preventive Inspection Repair Working hours State

4. 4 Challenge the future “bath tub” curve based on the observation of many actual failures conditional failure rate h(t) = f(t)/{1- F(t)} Conditional failure rate Time NewOld

5. 5 Challenge the future Hydraulic and Port Engineering Corrective maintenance Is not advised in view of the risk involved: partial closure of the port Preventive maintenance Time based Use based Load based Resistance based w

6. 6 Challenge the future Conditional failure rate Hazard rate Pr {R<S} in year n, given survival to n No deterioration of R Sea dike Height dike Stays the same If “it” works failure rate is dropping

7. 7 Challenge the future Are good deterioration models available?

8. 8 Challenge the future Dike settlement S.L.S.h 0 -A.Int = h(t) U.L.S.H(t)-HWovertopping

9. 9 Challenge the future Channel siltation S.L.S.d 0 -  z i = d(t)random walk U.L.S.d(t) - d ship grounding

10. 10 Challenge the future Value of inspection

11. 11 Challenge the future The life cycle cost problem Minimize total cost: Investment Inspection Repair Risk = p failure x Consequence C total = C invest + C insp + C repair + p fail x C Minimize PV{C total }

12. 12 Challenge the future Capital dredging → Investing Echo sounding → Inspection Maintenance d. → Repair Pr(grounding) → Risk  Dredging cycle 2-5 years

13. 13 Challenge the future The economic life cycle problem More alternatives: 1. Repair old structure 2. Build new structure Minimize total cost! Economic lifetime < Technical lifetime New structureOld structure Wages Fuel Material Inspection Repair Depreciation- Interest- Insurance (risk) Integral cost new <Variable cost old Technical lifetime Economic lifetime

14. 14 Challenge the future Economic life cycle approach Economic point of view: A Revenue B Cost Not only costs New structureOld structure Revenue new Revenue old Integral cost new Variable cost old Profit new >Profit old

15. 15 Challenge the future Economic life cycle approach Planned economic life time > Real economic life time -Loss of investment Intensify use Move assets to other location Reassemble assets for other function Built in flexibility Underlying assumption: Technical lifetime > Economic lifetime Most promising

16. 16 Challenge the future Economic life cycle approach of the port system - deep water channel - Entrance channel - Breakwaters - Port layout + handling - Quays and jetties - (un)Loading equipment - Inland transport Limiting factor! Revenue orientation Changes in relative costs Organization port & traffic Focus is on

17. 17 Challenge the future Cause of value

18. 18 Challenge the future Conclusions Maintenance theory is an aid to life cycle management. Focus on risk of failure Include the renewal option in life cycle cost management New opportunities are more important than optimal maintenance Optimize the port system spending on limiting factors Do some dismal thinking to find the bright ideas