eurocodes for the assessment of the existing structures
DESCRIPTION
ICE Coventry & Warwickshire Event: “Eurocodes: Are you being left behind?”TRANSCRIPT
Eurocodes for the assessment of the existing structures.
RWS Managing Contractor
Agenda:
1. Introduction� Bridges
� Defects
� Proposed Solution
2. Use of Eurocodes in Assessment.
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2. Use of Eurocodes in Assessment.� Lane arrangement
� Load Factors
� Reduction Factors
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.
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� Concrete overlay already decided solution for fatigue
Bridges
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•Waalbrug Ewijk
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•Waalbrug Ewijk
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Defects
� Orthotropic Decks
� Fatigue Problems
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Proposed Solution
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Eurocodes
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National Annexes
Design Memos
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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- NEN1994
Lane arrangement on the bridge:
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Lane arrangement on the bridge:
12.25 m
3.0 m 3.0 m 3.0 m 3.0 m
12.25 m
3.0 m 3.0 m 3.0 m 3.0 m
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3.0 m 3.0 m 3.0 m 3.0 m 3.0 m 3.0 m
Load Factors:
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Load Factors:
Action Default values
from Eurocode
Dutch National
Annex
Modified values for
assessment
Permanent Load 1.35 1.5 1.25 (6.10a)
1.10 (6.10b)
Variable Traffic
Load
1.35 1.5 1.10 (6.10a)
1.25 (6.10b)
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Other Variable Load 1.5 1.65 1.2 (6.10a)
1.5 (6.10b)
Reduction factors.
� Shortening of the reference design life
� Trend reduction in load magnitude
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Shortening of the reference design life:
0.96
1.0
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Reference period Reduction factor
100 years 1.00
15 years 0.95
1.0 years 0.88
Month 0.82
Trend reduction in live load magnitude:
Influence
length L
[m]
2000 2010 2020 2030 2040 2050
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
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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
Trend reduction in live load magnitude:
Influence
length L
[m]
2000 2010 2020 2030 2040 2050
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
30 years
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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
Reduction factors.
� Shortening of the reference design life
� Trend reduction in load magnitude
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DL+0.96 x 0.95 x LL
Thank You
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