i am modeling a lightweight concret 1

[Rana741]

i am modeling a lightweight concrete flat slab but the mixture of concrete contains fibers in it how can i model it in Abaqus

 

[NOLAscience]

My understanding is that fibers are for shrinkage and temperature, not structural capacity. I've never specified fiber-reinforced concrete, so I am certainly not an expert on this subject. I recently read this while studying for a PDH course on Slab on Grade Reinforcing Design:
"Synthetic fiberglass and steel fibers can also help to control plastic shrinkage cracking and limit
the size of cracks when used according to the manufacturer's recommendations. However,
currently there is no data indicating that the use of such fibers allows for an increase in joint
spacing. In addition, currently ACI does not recognize fiber reinforcement as an acceptable
substitute for conventional reinforcement. In addition, fiberglass fibers can sometimes protrude
from the finish surface of the slab giving the concrete a “hairy” appearance."

 

[TigerGuy]

I heard a supplier of the steel fibers imply that the fibers are a wonderful substitute for reinforcing bar. Their claim was that since demolition of fiber reinforced slabs is more difficult, it must provide excellent reinforcing strength.

I've also had to inform people that, "No, steel fibers in your concrete will not replace the reinforcing bar in a retaining wall." Lots of crazy claims out there.

 

[driftLimiter]

In order to model something like this in abaqus one must fully understand the material behavior.

Fiber admixtures are commonly used to provide crack control for slabs on grade. However I agree with above statements, the fibers do not contribute to tensile capacity of concrete sections.

OP must determine what the model is to be used for: Are you modeling for determination of crack control? Are you modeling a structural member with traditional reinforcement as well? How might the presence of fibers effect the model? Are the fibers even relevant to what you are trying to model?

 

[BridgeSmith]

Steel fibers can provide tensile capacity to concrete, but not in the concentrations and mixing methods typically employed at ready-mix plants. It takes a much higher volume of steel fibers, and a much more precise method of adding the fibers to the mix, to provide even distribution. Not to mention, a much more involved testing regimen, to ensure the tensile capacity has been achieved. All in all, it's much more expensive than using conventional reinforcing. The tensile strength is typically a side effect of the required ultra high compressive strength required in the specialty applications for which it's used.

Rod Smith, P.E., The artist formerly known as HotRod10