This document discusses the use of Eurocodes for assessing the strength of existing bridges in the Netherlands. It outlines the bridges that need renovation due to fatigue and strength issues. The Eurocodes will be used to evaluate the bridges, taking into account load factors, reduction factors for shortened design life and decreasing live loads over time. Lane configuration, load factors and reduction factors are presented from the Eurocodes and modified for use in the assessments.

1. Eurocodes for the assessment of the
existing structures.
RWS Managing Contractor

2. Agenda:
1. Introduction
Bridges
Defects
Proposed Solution
2. Use of Eurocodes in Assessment.
Lane arrangement
Load Factors
Reduction Factors
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3. Introduction
Joint Venture : Royal Haskoning, Arup, Greisch
Client : Rijkwaterstaat
8 Major bridges in the Netherlands fatigue and strength issues
Renovation over an 8 year programme
To give 30 yrs. further useful life.
Concrete overlay already decided solution for fatigue
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4. Bridges
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5. • Waalbrug Ewijk
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6. • Waalbrug Ewijk
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7. Defects
Orthotropic Decks
Fatigue Problems
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8. 8

9. 9

10. Proposed Solution
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11. 11

12. Eurocodes
National Design
Annexes Memos
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13. Eurocodes used for the assessment:
Eurocode 0: Basis of structural design - NEN1990
Eurocode 1: Action on the structures - NEN1991
Eurocode 2: Design of concrete structures - NEN1992
Eurocode 3: Design of steel structures - NEN1993
Eurocode 4: Design of composite steel and concrete structures
- NEN1994
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14. Lane arrangement on the bridge:
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15. Lane arrangement on the bridge:
12.25 m 12.25 m
3.0 m 3.0 m 3.0 m 3.0 m 3.0 m 3.0 m 3.0 m 3.0 m
3.0 m 3.0 m 3.0 m 3.0 m 3.0 m 3.0 m
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16. Load Factors:
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17. Load Factors:
Action Default values Dutch National Modified values for
from Eurocode Annex assessment
Permanent Load 1.35 1.5 1.25 (6.10a)
1.10 (6.10b)
Variable Traffic 1.35 1.5 1.10 (6.10a)
Load 1.25 (6.10b)
Other Variable Load 1.5 1.65 1.2 (6.10a)
1.5 (6.10b)
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18. Reduction factors.
Shortening of the reference design life
Trend reduction in load magnitude
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19. Shortening of the reference design life:
1.0
0.96
Reference period Reduction factor
100 years 1.00
15 years 0.95
1.0 years 0.88
Month 0.82
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20. Trend reduction in live load magnitude:
Influence 2000 2010 2020 2030 2040 2050
length L
[m]
0 1.00 1.00 1.00 1.00 1.00 1.00
20 0.89 0.91 0.93 0.96 0.98 1.00
50 0.82 0.86 0.89 0.93 0.96 1.00
75 0.78 0.83 0.87 0.91 0.96 1.00
100 0.76 0.81 0.85 0.90 0.95 1.00
150 0.75 0.80 0.85 0.90 0.95 1.00
200 0.75 0.80 0.85 0.90 0.95 1.00
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21. Trend reduction in live load magnitude:
30 years
Influence 2000 2010 2020 2030 2040 2050
length L
[m]
0 1.00 1.00 1.00 1.00 1.00 1.00
20 0.89 0.91 0.93 0.96 0.98 1.00
50 0.82 0.86 0.89 0.93 0.96 1.00
75 0.78 0.83 0.87 0.91 0.96 1.00
100 0.76 0.81 0.85 0.90 0.95 1.00
150 0.75 0.80 0.85 0.90 0.95 1.00
200 0.75 0.80 0.85 0.90 0.95 1.00
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22. Reduction factors.
Shortening of the reference design life
Trend reduction in load magnitude
DL+0.96 x 0.95 x LL
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23. Thank You
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