Edencrete | Enhanced performance of concrete with Carbon Nanotube liquid additive

Enhanced performance of Concrete with the Use of

Carbon Nanotube

Enriched Liquid Additive

Contact Details: tasha.eagle@fosroc.com.au +61 439 399 525

WHAT ARE THE BENEFITS OF CARBON NANOTUBE-ENRICHED LIQUID ADDITIVE IN CONCRETE?

STRONGER, MORE DURABLE, LESS PERMEABLE CONCRETE Reduced – shrinkage and cracking potential Reduced Abrasion - longer service life, harder wearing concrete Greater Strength – compressive, flexural, and tensile Reduced Permeability – reduce moisture and chloride ingress Increased MOE – improved ductility Increases Cement Efficiency - Optimises Pozzolanic mixes

Content  Introduction to Carbon Nanotubes (CNTs)  How do CNTs work in concrete and are they safe?  Strength & Durability  Abrasion Resistance

Case Studies

 Reduced Permeability  Reduced Cement and CO2 omission impacts  Korean Durability Study: Crack resistance and shrinkage reduction

Carbon nanotubes Plastics, Paints, Rubber, Batteries, supercapacitors etc.

x CH4(g) → (x-1) CH4(g) + 2 H2(g) + CNT(s) Concrete

Why CNT in Concrete?

CNTs are interesting.

The uniqueness present in their properties:    

Extreme mechanical strength, but flexible Electrical freaks; conducting or semi-conducting or both Optical interesting; perfect black Thermal conductor CNF

https://en.wikipedia.org/wiki/Carbon_nanotube

Suspension and Dispersion A good dispersion secures that CNT does not leave the solution again A good dispersion optimize performance of each individual CNT

How CNT’s work in Concrete Physical function arresting microcracks.

Chemical function as a guide for crystal growth.

Helium-Ion Microscope image Carbon nanotube (highlighted red) with cement hydrating on the surface

The nanotubes are ‘functionalized’ to provide: 

heterogenous nucleation points for cement hydration



A guide for directional crystal growth

https://en.wikipedia.org/wiki/Carbon_nanotube

Colour Impact?

White Cement + 2% Red

Grey Type I/II (GP)

White Cement Note: 1st GEN EC in 2015; Max. dose equivalent to current EC HC = 10L/m3

20L/m3

10L/m3

0L/m3

Safety of CNT additives  Safe for use.  Refer to the Safety Data Sheet  Refer to our Safety Charter   

External Independent testing Internal air filtration testing Independent Toxicologist report

Project Review

Georgia Department of Transportation – I-20 Trial #1 October 2015

The Objective:  Improve Design Life – durability  Improve strength  Increased abrasion resistance  Decrease cracking The Test:  2 x 10.5 meter long highway sections = 12m3 per slab  Slabs directly adjacent, identical in service conditions  All sampling done from truck at site Table 1: GDOT I-20 Trial #1 – Section 504 Concrete Design Requirements Minimum Cement Content Water to Cement Ratio Air Content Slump 3 (Maximum) (%) (mm) (kg/m )

446

0.45

 CaCl2 flakes accelerator at ≤ 4% cement  CNT equivalent = 10 L/m3

3 to 6

50 to 125

Compressive Strength (mpa) 17.2-mpa @ 24-hours 24.1-mpa @ 72-hours

Project Review

Georgia Department of Transportation – I-20 Trial #1 Evaluation

Figure 3: GDOT Trial #1 – I-20W Sub-base Preparations for Slab with CNT Additive

GDOT Trial 1 Federal Interstate Highway Application (I-20 Westbound)

60

Geoprgia Dept. of Transportation S&ME Lab Results I-20 Trial #1 CNT Additive w/ CaCl2 Control w/ CaCl2

50

47

Compressive Strength (MPa)

41 40

36 30

30

30 33

35

27 20

23

22

24-Hour

3-Day

10

0

0 0

Note: Ave of 25% increase

Age

7-Day

28-Day

56-Day

GDOT Trial 1 Federal Interstate Highway Application (I-20 Westbound) Abrasion Resistance - ASTM C779, Proc. C 4.2.3 Procedure C—The ball-bearing machine operates by high-contact stresses, impact, and sliding friction from steel balls. Plots the depth of abrasion wear vs time. 25 pounds of pressure, 1000 rpm

GDOT Trial 1 Federal Interstate Highway Application (I-20 Westbound)

Note: 1st GEN EC in 2015; dose equivalent to current EC HC = 10L/m3

Project Evaluation Full Year Cycle

Reference slab shows:

 Severe raveling at joints  Severe cracking  Deterioration of broom finish

CNT additive® slab shows:  No raveling at joints  No cracking  No surface defects

Project Evaluation Full Year Cycle

Stormwater Drainage: 1.5 years Trial Results 1.5 years: Reference pans show:  Pitting from chemical attack  Abraded and stained  Loss of broom finish EdenCrete pans show:  No pitting or scaling  No loss of surface finish  Minimal abrasion December, 2016

Reference

December, 2016

EdenCrete®

Stormwater Drainage: 4 years Reference

Reference

EdenCrete HC

AU Cylinder testing observations June 2020, Wyong

 <7mm aggregate cast for Abrasion tests (MA20)  Control = Pull out, splintering and ravelled edges  CNT - HC Trial mix = smooth surface, edges in tact

CNT for permeability Metropolitan Atlanta Rapid Transit Authority (MARTA); Municipal Vehicle Transportation Terminal

Trial Goals: 1) Extend in-service durability 2) Reduce permeability 3) Improve resistance to abrasion Concrete Mix Design Item Cement Type I/II (GP) Boral Flyash 25mm Coarse 5mm Coarse Sand Water AEA WR HWR

w/c = 0.39

w/c = 0.39 CNT = 7.5L/m3

Weight

Unit

316 kgs 106 kgs 675 kgs 365 kgs 651 kgs 168 kgs 0.10 mls 1.10 Litres 0.96 Litres

CNT for permeability: MARTA trial ASTM C1543 - Standard Test Method for Determining the Penetration of Chloride Ion into Concrete by Ponding (AASHTO T 259)

50mm diameter core

100mm H

Test is indicative of concrete permeability:  3% chloride solution ponded for 90 days  Core sample taken from slab center  Cross-sections cut from core sample, pulverized and analyzed for % chloride weight per ASTM C1152

Ponding Slab Test Sample

Figure 3: 2 years later, CNT slab (Left of joint) adjacent to Reference slab (Right of joint)

CNT for permeability: MARTA trial EdenCrete®

Reference 10 – 20 mm

0.055 % chloride

High Concentration

0.006 % chloride

25 – 35 mm

0.039 % chloride

0.001 % chloride

40 – 50 mm

0.001 % chloride

Chloride Concentration vs.

Depth

55 – 65 mm

0.001 % chloride

No Concentration

0.000 % chloride

0.000 % chloride

Approximate depth of concrete ‘cover’ over steel reinforcement; ≈ 1.5 – 2.0” (≈ 35 – 50 mm)

Reduced Permeability –

AU PRECAST TRIAL 2019

Determination of Chloride Ion Diffussion Coefficient Nordtest Method NT Build 443 1995-ll

Reference: De = 2.38E-11 m2/s and 2.45E-11 m2/s

EdenCrete HC: 2.5 L/m3: De = 8.00E-12 m2/s and 1.09E-11 m2/s

EdenCrete HC: 7.5 L/m3: De = 1.09E-11 m2/s and 1.10E-11 m2/s

Increased Design Life Example Laboratory Trial Brisbane, Australia May 2020 Mix Details

Service Life Prediction – Modelling in Life-365

 Precast Mix 50/20/120  Total Cementitious 526kg/m3  Ternary BlendGP/FA/SLAG

 % - 55/25/20  w/c – 0.37 Note: Trial mix = 10% increase in mpa strength vs. control

Program Inputs  Concrete - EX HC + $50/m3 Concrete vs. Control  Construction costs SAME

Reduced Shrinkage -

AU PRECAST TRIAL 2019

Ternary Mix Design – S50/14/720 Shrinkage in Microstrain MEAN Results Drying Shrinkage Age 2.5L 5L (weeks) Control EC HC EC HC 1.0 370 390 360 2.0 480 490 460 3.0 560 550 520 4.0 610 600 560 5.0 660 640 600 6.0 690 670 630 7.0 710 690 640 56 Days 8.0 740 710 660 11% Reduction 90 Days 13.0 800 720 710 12% Reduction

Georgia Ports Authority – RTG Crane Runway Repair Project: Feb 2020, Port of Savannah, 35 MPa RTG runway, 5 L/m3 EdenCrete HC

Challenge:

 Early strength  Long Design Life  Extended Durability

Edencrete Goals:

 Improve durability, abrasion and cracking.  Open-to-service strength quicker than the traditional mix.

Georgia Ports Authority – RTG Crane Runway Repair Project: Feb 2020, Port of Savannah, 35 MPa RTG runway, 5 L/m3 EdenCrete

Georgia Ports Authority – RTG Crane Runway Repair Project: Feb 2020, Port of Savannah, 35 MPa RTG runway, 5 L/m3 EdenCrete

Results:     

Design strength achieved in 1 day - 35mpa Double design strength at 28 days – 70mpa Durability evaluations passed at 60 days – goal was 90 days.

At 60 days no cracks or abrasion damage.

In-service project review ongoing.

Moffatt & Nichol has recommended EdenCrete for the next three GPA repair jobs.

CNT replacing cementitious in pozzolanic mixes* NEW YORK TRIAL – ECONOMIC VALUE EQUATION (EVE) DESIGN MIX (70mpa) 800C 76mpa

TRIAL MIX 1 650C 76mpa

$66/m3

$66/m3 $64/m3

480KG CEMENT 390KG CEMENT

• •

TRIAL MIX 2 650C 73mpa

390KG CEMENT

288kg GP = $43/m3 192kg SLAG = $23/m3

234kg GP = $35/M3 156kg SLAG = $19/m3 0.9L EC Pz = $12/m3

60/40 Slag/GP

60/40 Slag/GP

40/60 Slag/GP

90kg total Cement CUT

90kg total Cement CUT

0.9L Edencrete Pz

0.9L Edencrete Pz

Apply AU costs per KG of GP = $0.15 Apply AU costs per KG of SLAG = $0.12

* This example includes conversions from Imperial to metric; is specific to this trial ONLY. * Assumes 900kg CO² emitted per 1000kg GP cement

156kg GP = $24/M3 234kg SLAG = $28/m3 0.9L EC Pz = $12/m3

This Example – Sustainability GP Cement Cut = 132kg/m3 132kg x 0.9 = 119kg less carbon omission*

Korean Durability Study

Korean Durability Study

Only A,B & C are comparative in this trial.

Korean Durability Study

Korean University Study

9% 11.5%

Korean Durability Study

31.5%

50%

Korean Durability Study

Conclusion STRONGER, MORE DURABLE, LESS PERMEABLE CONCRETE

Contact Details: tasha.eagle@fosroc.com.au +61 439 399 525