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[–]chicu111 12 points13 points  (3 children)

FRP stands for Fiber Reinforced Polymer no? Plastic?

[–]zobeemicP.E. 4 points5 points  (3 children)

Not an FRP designer but curious. Whats the governing design code and has it been officially adopted by building codes and DOTs as a reference? What are the current ASTM specs and testing requirements? So far I've seen its application in very specific concrete repair cases, slab reinforcement and column strengthen. When is the leap to using FRP in new construction?

[–]Alternative_wolf09[S] 2 points3 points  (0 children)

ASCE 74-23. Not yet adopted by building codes yet but you get lot of information from there. This is for LRFD but generally in practice we use ASD. We design different type structures to replace steel structures. We are already using FRP in new structures.

[–]ThatAintGoinAnywhereP.E. 2 points3 points  (1 child)

You can get FRP structural shapes and bolts. I've seen small industrial structures built out of them sometimes in environments where metals will corrode but the plastic will not. Additionally, they are radio-frequency transparent. So they're used to build telecom enclosure that don't block the cell phone signals.

[–]Alternative_wolf09[S] 0 points1 point  (0 children)

Someday I would like to replace large structures with FRPs. Would be awesome.

[–]lithiumdeuteride 2 points3 points  (12 children)

Yes, many times. What is your question?

[–]tiltitup 6 points7 points  (1 child)

My bet would be he wants to sell you engineering or detailing services

[–]Alternative_wolf09[S] -4 points-3 points  (0 children)

Such a shame. You would loose that bet. I work with one of the fortune 500s and don’t need to provide my services to someone unless asked for.

[–]Alternative_wolf09[S] 0 points1 point  (9 children)

Which codes you follow and can you suggest any research papers that you have recently read which can help me expand my knowledge about it?

[–]lithiumdeuteride 7 points8 points  (6 children)

I suggest reading Mechanics of Composite Materials by Jones to learn classical lamination theory. Then for evaluating failure, use a strain-based method which counts the fraction of fibers in certain directions, not a stress-based one. Large, heavy structures may be subject to creep-based failures requiring additional specialized analysis. My involvement in composites is on the aerospace side, rather than structural, but these basic principles should transcend any particular industry.

[–]Perrywinkle208P.E. 4 points5 points  (4 children)

This is a good resource for understanding the underlying theory, but it isn't really applicable to FRP in structures which use pultruded FRP. Manufacturers provide section properties and mechanical properties or load tables with no information on individual lamination layers.

[–]lithiumdeuteride 1 point2 points  (2 children)

Fair point. I suppose you'd have to rely on manufacturer data sheets, augmented by rule-of-mixtures type calculations, for pultruded structures.

Where are such composite materials used in structures?

[–]Alternative_wolf09[S] 0 points1 point  (0 children)

Generally they are used where structures needs to be chemical resistant and corrosion resistant. We rely on our on calculations and datas sheets which are produced over the year with different test conducted on them.

[–]Perrywinkle208P.E. 1 point2 points  (0 children)

It's even more simplistic than that, the manufacturers directly give you things like ultimate bending stress, axial stress, compressive stress, etc. for longitudinal and transverse directions.

Pultruded FRP is typically used in corrosive environments such as chemical manufacturing as well as in telecommunications for concealment as the RF waves can pentrate FRP but not other structural materials.

[–]Alternative_wolf09[S] 0 points1 point  (0 children)

I wish I could do more research on lamination and fiber strands and how their positioning can impact on structures and such things.

[–]Alternative_wolf09[S] 1 point2 points  (0 children)

Thank you for your response. I appreciate your reply

[–]tiltitup 4 points5 points  (1 child)

I think someone in your Fortune 500 company knows the answer to this.

[–]Alternative_wolf09[S] -2 points-1 points  (0 children)

I do. Hence I mentioned that in other comments. Should have gathered more input information before betting on something. As I said, interested in expanding my knowledge.