Reinforced concrete reinvented
Jeroen Smet
Let’s presume
• You all know the benefits of using FRC:• Installation time is 50% of steel mesh• 0% corrosion • 15-40% cheaper solution than steel mesh• 100% Safer
ASTM C 78, JSCE-SF4
Residual Flexural strength
• Concrete = brittle• The bond between the cement and the aggregate => strength
ASTM C 78, JSCE-SF4
Flexural Strength is NOT Increased
Flexural Strain Capacity ISEnhanced
Residual Flexural strength
• FRC => Residual Flexural strength• Fibres take the tension and transfer this tension to un-cracked
areas
Cracks are held together
Residual flexural strength
Test set-up Plain Concrete FRC
Beam test
Brittle Flexural strength
Residual Flexural strength
Residual Flexural Strength
• Re3-value: residual flexural strenght• 3 point bending test• Determined @WTCB
Residual Flexural strength
Design: Slab on grade
Design Service
• Supported floor slab:• Done against CS-TR34-4th edition• In line with the latest Eurocodes and Standards• Limit state format: ULS and SLS• ULS => Meyerhof equations (Partial Safety Factors acc. EC2)
Design service
Comparison of different design methodologies for FRC Slabs on grade - Sunitha K Nayar and Ravindra Gettu
Design service
• ConCribe:• Engineering buro• Experienced with FRC• Floors – Precast designs• PI
• Own Software (sLade) designed by ConCribe• Supported FRC slab• PI • Very fast respons
Design: Slab on grade
Increase energy absorption
Increase energy absorption
• Shotcrete for tunneling requires energy absorption (500,700 &1000 Joule)
• EFNARC plate test ASTM C1550 RDP TEST
Increase energy absorption
Improved impact resistance16mm rebar reinforcement
Improved impact resistanceFibre reinforcement
Improved impact resistanceFibre reinforcement
Improved impact resistanceFibre reinforcement
Durability
• Polypropylene = inert
• Durability of PP fibers in portland cement-based composites: eighteen years of data –D.J. Hannant
• Can be influenced in time by:
• UV radiation
• Oxidation
• Accelerated aging test: EN ISO 13438
• Service life: 25, 50 and 100 years
• 50% residual tensile strength
• S500 lost 32% strength and only 7,1% Modulus (100 years)
Durability
Creep
General:
• Not taken into account in MC 2010• International round robin test (19 labs) supported by RILEM TC
261-CCF• Improving knowledge on creep behaviour of FRC (Steel &
Polymer)• Check different test methodologies
Creep
In Adfil:
• Different fibre generations have been tested• Continiously improved• Phd @ KU Leuven
Creep
Fibre level:
Creep
Focus on segments not subjected to creep:- Flooring & foundations- Shotcrete(1)
- Precast(2)
Structural applications: hybrid reinforcement(3)
(1) Influence of Fibres on the Creep Behaviour of Reinforced Sprayed Concrete presented by Catharine Larive on WTC 2016
(2) PP FRC concrete pipes under sustained loading presented by Emmanuel Attiogbe on BEFIB 2016
(3) Brittle vs. ductile behavior of concrete beams reinforced with steel rebars and fibersGorino, A., Fantilli, A., Chiaia, B., Zampini, D.,
Creep
Creep test on concrete tubes:
- Primary reinforcement
- Longtherm serviceability factor α
- a ≥ 0,90 provides sufficient longtherm post-crack strength
- ASTM C1818 prequalify synthetic fibres for use as primary reinforcement
Applications
• Seawall defence• 4000m³• 4kg/m³• Eleminate corrosion
Applications
• Screed topping 50mm• Not enough covering for steel• 2400m³• 5kg/m³
Applications
• Extruded concrete• >100 Tonnes
Applications
• Housing• Durus S400 adopted as standard
reinforcement in beam and block floors by NHBC
• 4kg/m³
Thank you
Jeroen SmetProduct/Application Managerwww.adfil.be