Life Cycle Analysis Issues in the use of FRP Composites in

Transcription

1 Life Cycle Analysis Issues in the use of FRP Composites in Civil Infrastructure Charles Bakis The Pennsylvania State University University Park, PA, USA Life Cycle Assessment of Sustainable Infrastructure Materials Oct , 2009 Hokkaido University, Sapporo Japan

2 Inputs? + Then what? Outputs? How? = (Butler Cnty. Engrs. Office, OH)

3 Stronger, Stiffer, Lighter...

4 Fibers Strong, stiff Polymer matrix What is inside? Ductile; protect/support pp fibers Fillers, veils Cost reduction Shrink & exotherm control Flame retardant UV protection Surface finish & durability Cross Section

5 Material Design: The Boon and Bane of Composites Ways to lay up composites Wonderful tailorability Poor primary recyclability Quasi Isotropic (Daniel and Ishai, 1994)

6 Specific Strength and Modulus: Quasi Isotropic Composites Specific Tensile Strength, GPa/(g/cc) / Material differences, residual stresses, etc. Specific Tensile Modulus GPa/(g/cc) Glass/ep 0 deg. <21,0.55> Carbon/ep 0 deg. <94, 1.4> (Based on Reinhart and Clements, 1987)

7 Fibers St tress (MPa) Carbon Glass Aramid Steel Strain (m/m) Force Initial Displacement Typical lfibers have high h elastic deformability & strength, but little to no plastic deformability Can increase deformability by tailoring the fiber angle and type of matrix Pulled

8 Carbon Fiber Production Single end, d or tow (Graphic source: unknown) Oil based, energy intensive, US$/kg

9 Glass Fiber Production Single End Energy intensive ~2 US$/kg Multi end tows have less strength & stiffness than single end (Graphic source: unknown)

10 Plant Based Fibers Stress (MPa) E glass Flax Renewable Hemp Kenaf Low embodied energy Jute Abaca Sisal Coir (eg. Kenaf: 75% reduction vs. glass) 40% less dense than glass Degradable Strain (m/m) Moisture sensitive, temperature limited

11 Keratin Fibers Feather Fibers Quill Fiber (Hong & Wool, 2004) Renewable Waste product looking for a good use 67% less dense vs. glass 90% less modulus and strength vs. glass Moisture sensitive, temperature limited

12 Fillers Natural minerals calcium carbonate clay aluminum trihydrate Manufactured products metal powder glass beads phenolic powder Renewable products wood flour ground rice hulls peanut shells hll The original multifunctional filler for composites New functions? (eg., end of service recycling?)

13 Matrix Materials Thermosets (eg., polyester, vinylester, epoxy) Good processing and cost characteristics Cannot be thermally formed or separated from fibers Thermoplastics eg., PET, PU Good recycling potential, formable Melt viscosity, bond, fatigue issues Plant based epoxies Renewable: soy, linseed Low stiffness (Fulcrum Composites)

14 Manufacturing: VARTM Resin Inlet Vacuum FRP plate Tool plate Vacuum Assisted Resin Transfer Molding eg., bridge decks, boats, windmill blades (E. Strauch, Penn State U.) (D. Cripps, Gurit)

15 Manufacturing: Pultrusion eg., structural shapes (Strongwell) Pull fibers through resin and mold Shape and cure composite in mold Continuous, high speed process (cheap) (Howard Univ.)

16 Pultruded Parts (Strongwell) (Butler Cnty. Engrs. Office, OH)

17 Closing Thoughts Composites are heterogeneous, anisotropic, highly tailorable and integratable, but not amenable to primary recycling need good ways to utilize material post service Connections among {environmental effects, human effects, raw material lfeed stocks, manufacturing methods, material design, embodied energy, transportation costs, disposal/recycling costs, etc.} are not well described dor understood d solutions require multi disciplinary approach materials science, chemical engineering, g mechanics, structural engineering, manufacturing engineering, business analysis, transportation engineering, environmental engineering, law, and climatology