UHPC for innovative architectural and structural

solutions

LafargeHolcim member of Febelcem

What is UHPC – Terminology ?

• HPC High Performance Concrete

• UHPC Ultra High Performance Concrete

• UHPFRC Ultra High Performance Fiber Reinforced Concrete

• BUHP Bétons à Ultra-Haute Performance

• BFUP Bétons Fibrés à Ultra haute Performance

• UHFB Ultra HochFester Beton

• UHSB Ultra Hoge Sterkte Beton

• RPC Reactive Powder Concrete

• Classification mostly based on compressive strength …

0 20 40 8060 100 120 140 160 180 200 MPa

'Normal' concrete

High Performance

concrete

Ultra High Performance concrete

RPC

What is UHPC – Mix Design Principles ?

• Particle size optimization of all components: cement, SCM (silica fume) and fine sand (although some may use coarse aggregates D8)

• Extremely low W/C-ratio (< 0,26) using highly powerful admixtures

• Self-compacting/levelling characteristics (perfect filling of moulds)

• Enhanced ductility (post-cracking) through steel/synthetic fibers

What is UHPC – Mix Design Principles ?

self-compacting properties

50 mio fibers / m3

extremely dense microstructure

careful mixing process

What is UHPC – Mechanical properties ?

Normal HPC UHPC*

Compressive strength (MPa) 30-60 60-120 150-180

Direct tensile strength (MPa) 2,5 – 4,0 4,0 – 6,0 7,0 – 9,0

Eq. Flexural strength (MPa) / / 15 – 30

E-modulus (N/mm²) 30.000 – 38.000 35.000 – 40.000 45.000 – 55.000

Shrinkage (mm/m dry env.) 0,5 – 0,7 0,5 – 0,7 0,5 – 0,7 **

Creep coefficient 3 – 5 2 – 3 ≈ 1 **

Thermal dilatation (m/mºC) 8 – 12.10-6 10 – 12.10-6 10 – 12.10-6

Abrasion resistance

* Ductal® MF (metallic fibres) – no thermal treatment** much smaller with thermal treatment

What is UHPC – Mechanical properties ?

• Ductility … blast & impact resistance … fatigue …

• Important volumes of fibers: steel & PVA (PP for fire resistance)

Normal HPC UHPC*

Capillary pores1 [%] ± 8 ± 5 1,5 à 2,0

Water absorption2 [kg/m²] ± 60 ± 11 1

Nitrogen permeability3 [m²] 10-16 10-17 < 10-18

Oxygen permeability4 [m²] 10-15 - 10-16 10-17 < 10-19

Freeze-thaw resist.5 [g/m²] >1000 < 900 < 60

Chloride ion diffusion6 [mm] 23 8 1

Carbonation resist.7 [mm] 7 4 1,5

What is UHPC – Durability properties ?

* Ductal® MF (metallic fibres) – no thermal treatment

1 Volume of capillary pores to total volume2 Water surface absorption (24h) according to DIN 52617 3 According to FR standard4 According to FR standard5 Surface scaling in salt presence according to AFNOR P18-240 (60 cycles)6 Depth of intrusion after (6h) quick migration test – Tang and Nielsson 19927 Depth of carbonation (3y) non accelerated test 20ºC/65%RH)

What is UHPC – Aesthetic qualities ?

• very fine cementitious matrix allowing to replicate all mould asperities and textures

• Colour palette from white to black & all other colours (in mass)

• Application of surface protection recommended

What is UHPC – conclusion ?

• "A mineral product between concrete and steel"

Overview of (existing) applications

Mechanical Performance

DurabilityPerformance

Surface/Aesthetic quality

footbridges

bridge jointsbridge decks

columns & beams

mantillas

cladding

roofs & canopies

balconies

furniture

roofs & canopies

blast & impact resistance

dam protection

Zoom on a project … "cladding / surface quality"

RA

TP

de

TH

IAIS

, 2

00

7

Zoom on a project … "cladding / surface quality"

Bus Station, Thiais, Paris

• Owner: RATP, FR

• Architect: ECDM (Emmanuel Combarel Dominique Marrec), FR

• Precast producer: Betsinor, FR

• UHPC:

Zoom on a project … "structural / durability"

ST

AD

E J

EA

N B

OU

IN,

20

12

-201

3

Zoom on a project … "structural / durability"

Stade Jean Bouin, Paris

• Owner: Ville de Paris, FR

• Architect: Rudy Riciotti, FR

• Precast producer: Bonna sabla, FR

• 10.000 m² roof elements

• 11.000 m² façade elements

Zoom on a project … "structural / durability"

VIA

DU

C D

E C

HIL

LO

N, 2

01

4

Zoom on a project … "structural / durability"

Viaduc de Chillon, Zwitserland

• Owner: OFROU – Office Fédéral des Routes, CH

• Architect: /

• Contractor: Walo Bertschinger AG, CH

• UHPC: 1200 m3 / 24.200 m²

How to design UHPC ?

• France

– AFGC/Sétra Recommendations 2002

– AFGC Révision 2013

– NF under development

• US

– FHWA field-cast bridge deck connections

• Japan, Australia recommendations

• Publications under development

– DAfStB Richtlinie

– fib Bulletin (TC 4.2)

– CEN

– RILEM TC HFC High Performance Fibre

Reinforced Cementitious Composites

Conclusion:

• UHPC offers potential for many (new) applications given the extraordinary:

– Structural behaviour

– Low porosity

– Surface characteristics

• Continued research needed (ongoing) with regard to:

– Structural modelling

– Robustness of formulations

– Application methods e.g. spraying