This document discusses the development of eco-friendly high-performance concretes for use in the structural design of record-long suspension bridge towers along the E39 highway in Norway. The concretes were designed with low water-to-binder ratios of 0.35 or 0.30 and supplementary cementitious materials to reduce CO2 emissions. Testing showed strength development and durability suitable for the large bridge towers. Structural analysis and optimization methods were used to dimension the towers, resulting in up to 32% less concrete and 15% less reinforcement for a 2,050m main span bridge, reducing CO2 emissions by up to 60%. These concretes and design approaches could enable the construction of even longer suspension bridges.

1. Eco-friendly high-
performance concretes:
From particle packing to bridge
tower design for record long
suspension bridges along the
«Ferry-free E39»
Structural
strength
analysis
Material
design
CO2-emissions NCR Stockholm August 17th 2022
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2. Carry out R&D contributing to make the pioneering projects possible
From 0 to C100 in 91 days –
Project title: Concrete C100 and Related Structural Design Topics for the E39 project
E39 Halsafjorden,
possibly a suspension
bridge with main span
2050m
E39 Sulafjorden,
possibly a suspension
bridge with main span
2800m
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3. 3
Project contents:
• Material design and strength development
• Slipforming
• Shrinkage and early age stress development
• Durability testing
– Chloride ingress
– Frost resistence
• Crack width calculation methods
• Application in structural design of bridge towers
– Halsafjord bridge (2.05 km span)
– Sulafjord bridge (2.8 km span)
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4. Cement consumption: 1975: 460 kg/m3
1990: 410 kg/m3
2017: 350 kg/m3
From Kjell Tore Fosså, Kværner/UiS:
Improved materials
technology
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5. Mix
characteristics:
w/b=0.35
Norcem Anlegg FA(16%)
16% or 35% total FA-
content
3%, 8% or 16% Silica
Slump: 230-255mm
Slump-flow: 525-720mm
Separation problems in some
mixes
8% and 16% silica improves the
production properties
Compressive E-modulus at 28 and 91 d:
-Variation range 31.2-34.7 Gpa
- Increase from 28 to 91 days: 1.4 – 2.5 GPa
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6. w/b=0.30
Norcem Anlegg FA(16%)
16% or 35% total FA-content
3%, 8% or 16% Silica
Slump: 230-255mm
Slump-flow: 525-720mm
8 and 16% silica improves the
production properties
6
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7. Experimental results, basic shrinkage and
early age stress development
3
4
8
10
7
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8. 8
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9. 9
Design and calculation methods
• Work carried out by MSc-students
• Materials and cross sections from Hardangerbrua (main span 1310m) used as basis
• Cross sections of pylons, main cables, hangers and girder scaled with the use of
equations given in the text-book: Niels J. Gimsing and Christos T. Georgakis: Cable
supported bridges (DTU).
Two separate beam-element models (Abaqus):
• Pylons subjected to self weight and static wind
load during the construction phase
• Full suspension bridge subjected to self weight,
static wind load and traffic load
• Nonlinear geometric effects included to
model realistic tower and cable behaviour
• Dimensioning of towers based on ULS-
stiffness, not strength

10. 10
Optimization of solution towards low CO2-emissions
Geometry
Reinforcement
Geometry
Concrete

11. 11
• The cross section behaviour (MRd) is
determined from numerical integration
and the stress-strain relationships
• The 2nd order moment (M2) is linearly
dependent on the curvature
• The 2nd order moments from the Abaqus
analysis are dependent on the assumed
stiffness
• The first order moment capacity
(MRd1=MRd-M2) is available to carry the
wind load
• MRd1 max gives the optimum solution
• Iterations are necessary to find the
optimum solution
Dimensioning of towers based on ULS-stiffness
MRd
M2
MRd
MRd1max
MRd1
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12. 12
Iterations are necessary to find the optimum solution
MRd
MRd1max
As+AP
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13. 13
Conclusions
• High-performance concretes with w/b=0.35 or 0.30 and very low CO2-
emissions have been developed
• Application in large bridge-towers may save considerable amounts of both
concrete and steel
• Reduced sectional forces in the pylon legs were achieved due to reduced
self weight and reduced area for the wind load to affect
• For the Halsafjord bridge (L=2050m) this results in 32 % reduction in
concrete, and 15 % reduction in reinforcement
• The corresponding reduction in CO2-emissions was up to 60%
• Post-tensioned reinforcement has to be applied symmetrically in the
sections, and therefore reduce the axial force capacity
• For the Sulafjord bridge (L=2800m) it is still shown that post-tensioning
can be applied to save both concrete and steel, and therefore also
contribute to improved sustainability
Thank you for the attention