Pledge of Allegiance

I pledge allegiance to the Flag of the United States of America, and to the Republic for which it stands, one Nation under God, indivisible, with liberty and justice for all.

Acknowledgements

www.greencoastalstructures.com

www.miamidade-asce.org

GREEN COASTAL STRUCTURES

Green Coastal Structures was founded to implement FRP technology and SEACRETE® in coastal structures;

Green Coastal Engineering is a licensed and insured design and consulting firm specializing in FRP reinforced concrete structures providing cutting-edge design solutions to coastal engineering problems

Green Coastal Technologies offers SEACRETE® and SEABAR® (selection of quality-tested durable FRP concrete reinforcing rebars available on the market screened by our team of material scientists and engineers)

OUR LEADERSHIP

Antonio Nanni, Ph.D., PE, FACI, FASCE

Honorary Director (Pro bono)

Hany Jawaheri Zadeh, Ph.D., PE

Principal

Morteza Khatib, Ph.D.

Principal

South Florida COPRI

CoastsOceansPortsRiversInstitute

Tri-County Institute Comprising:Miami-Dade ASCE BranchBroward ASCE BranchPalm Beach ASCE Branch

For ideas on events, topics, or sponsorship opportunities please contact copri@miamidade-asce.org

Florida Infrastructure Report Card

If you are able to volunteer, please contact copri@miamidade-asce.org

NEXT GENERATION COASTAL CONCRETE STRUCTURES WITH NON-CORROSIVE FRP REINFORCING REBARS

MORTEZA KHATIB, Ph.D.

GREEN COASTAL STRUCTURES

NOVEMBER 6, 2019

OUTLINE

INTRODUCTION TO FRP CONCRETE REINFORCING

BARS

HOW TO DESIGN WITH FRP BARS

FRP-REINFORCED CONCRETE STRUCTURES IN STATE OF

FLORIDA

POTENTIAL OPPORTUNITIES TO IMPROVE THE SUSTAINABILITY

OF COASTAL STRUCTURES

PROBLEM = CORROSION

The global cost of corrosion is estimated to be US$2.5 trillion, which is equivalent to 3.4% of the global GDP (2013).

HOW TO AVOID CORROSION

Admixtures/Design low permeable concrete

Increase cover/coatings

Cathodic protection

Stainless steel/ChromX

Coated steel rebars

EPOXY COATED STEEL REBARS

GALVANIZED STEEL REBARS

Accelerated corrosion

Galvanic corrosion

Estimated to add only 5 more years to the service life of the structure

WHY NOT ELIMINATING CORROSION ONCE AND FOREVER?

FIBER REINFORCED POLYMER CONCRETE REINFORCING REBARS

Glass Fiber Reinforced Polymer (GFRP) Bars

Basalt Fiber Reinforced Polymer (BFRP) Bars

Carbon Fiber Reinforced Polymer (CFRP) Bars

WHAT IS FRPREBAR?

FRP rebars are made of Fibers embedded in Resin matrix

Fibers provide strength and durability

Resin holds fiber together, transfer loads between fibers, and protects from abrasion and environment

PRODUCTION PROCESS

KEY BENEFITS

100% corrosion resistant: no need for 3” cover, Corrosion inhibitor, sealant

Lightweight (1/4 the weight of steel): saving in transportation, labor, and carbon footprint

Superior tensile strength (80 – 175 ksi)

Cost effective: saving in construction, maintenance, and repair cost over the service life of structure

Provides opportunities for implementing more environmentally favorable concrete (SEACRETE ®)

LIMITATIONS

No yield (warning) before failure

Lower modulus than steel (45 – 60 GPa)

Can not be bent on the job site

Largest bar size for now is #10

LONG-TERM DURABILITY

PROVEN DURABILITY

According to field performance of existing FRP-reinforced concrete structures over the last 20 years and numerous research studies, the corrosion-resistant nature of this alternative has demonstrated its ability to extend the service life of concrete structures to more than 100 years.

Cores from a 17-year old bridge show no sign of damage

Cores from five concrete structures in Canada 12 to 15 years old showed similar performance

More than 500 projects in US and Canada used FRP rebars

PROVEN DURABILITY

PROJECTS WITH FRP CONCRETE REINFORCING REBARS IN FL

Low Impact Secant-Pile Seawall for protecting SR-A1A along Flagler Beach

PROJECTS WITH FRP CONCRETE REINFORCING REBARS IN FL

HOW TO SPECIFY AND DESIGN WITH FRP REBARS

HOW TO DESIGN, SPEC, AND BUILD

ASTM D7957-17 Defines material specifications

ACI 440.1R-15 Design with FRP rebars

ACI 440.5-08 Construction with FRP rebars

AASHTO LRFD bridge design guide specifications

HOW TO SPECIFY IN FLORIDA

FDOT design guidelines

Materials Manual for FRP bars

DESIGN CONSIDERATIONS

No ductility

Concrete Crushing as Preferred Failure Mode

Lower modulus

CONSTRUCTION CONSIDERATIONS

Lap splices longer

Support chairs at 2/3 conventional spacings

Bid by foot rather than pound

May need multiple pick up points

COST COMPARISONS

FDOT bid estimates:

#8 Steel Rebar: $2.67/ft vs #8 GFRP Rebar: $2.25/ft

POTENTIAL OPPORTUNITIES TO IMPROVE THE SUSTAINABILITY

SEACRETE ® Using seawater for mixing instead

of freshwater

Replacing natural aggregate in concrete with Recycled Concrete Aggregate and Recycled Asphalt Pavement

Replacing higher amount of cement with byproducts such as Slag and Fly Ash

Using low carbon cement

PROBLEMS

Insufficiency of drinking water for over half of the population of the world by 2025

600 Billion gallons of freshwater per year for concrete production

Cement production contributes 6% of annual global CO2

Aggregate mining has significant environmental impact

RESEARCH PHASE

International research project led by the University of Miami (SEACON)

Data from literature is very promising with corrosion as the only concern

Superior performance of concrete mixed with seawater in marine environment compared with conventional concrete

This attributed to higher degree of hydration and lower chemical gradient between SEACRETE® and surrounding seawater

Support marine ecosystems with more favorable pH and leveling the chemical gradient

SEACRETE ® REDEFINING

SUSTAINABLE CONCRETE

Conserves 100 gallons of freshwater per cubic yard

Conserves energy and natural resources

Reduces waste production and heavy landfill contributions

Reduces cement content due to higher early age strength

Reduces the carbon-foot print of the structure

Provides a more tolerant habitat for marine life

Reduces the environmental impact of concrete infrastructure

Durable in marine environment

DEMO PROJECTS

iDOCK

SEACRETE ® and SEABAR ®

2500 Gallons of freshwater were conserved

Estimated service life of 100 years

Almost no maintenance will be needed over the service life

HALLS RIVER BRIDGE

CONCLUSIONS

Eliminate corrosion in coastal concrete structures once and forever

by replacing steel rebars with FRP rebars

Complete set of materials specification, design and

construction guides are available for FRP concrete reinforcing rebars

Many concrete structures have been built with FRP rebars and are

performing well

Provide opportunities for more environmentally friendly and sustainable approaches in

construction

THANK YOU

EXAMPLE OF MATERIAL PROPERTY

Tensile Strength

Guaranteed Ultimate Tensile Strength: f*fu

Design Strength ffu=Ce x f*fu

Shear Lag (i.e., size effect)

HOW TO TIE REBARS