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This site claims that the small wires(twisted steel micro rebar) they created are a good replacement to a typical rebar concrete reinforcement if not even better.

a reinforcement technology that could product provide quantifiably
better resiliency, ductility and elasticity to concrete structures.

It's hard to believe that the small wires could replace long continuous rebars. Their product have been around since 2003 and if that's true what they claim how come I still mostly see the typical long reinforcement bars used on the construction sites? Shouldn't this be mostly used everywhere by now? It doesn't seem to be more expensive and also it is less labor demanding.

The question headline seems to be slightly misinterpreting the company's claims

Carefully rereading their claims, I realized they do not specify what Twisted Steel Micro Reinforcement (TSMR) reinforced concrete is better than. On a quick read, I just assumed they meant it is better than rebar reinforced concrete, because that is what the pictures imply, but it is never explicitly stated.

Helix Steel’s TSMR increases concrete’s strength and resilience and eliminates or reduces traditional reinforcement (rebar and mesh) required by building codes.

This sentence implies that traditional rebar reinforcement is still required in some cases; TSMR is not better than just rebar in all cases.

Helix's Science

Their publications page presents 3 conference papers, two technical reports, and an industry magazine article. I have skimmed through these and found experimental comparisons between plain concrete (not reinforced) and the twisted helix reinforced concrete. I could only find one comparison between rebar reinforced concrete and the helix reinforced concrete, and that related to the explosive test that their pictures show. No quantitative results were presented from that test, just the pictures.

It is worth noting that their best evidence is published as conference papers, which typically face a lower standard of peer review than journal articles. This is definitely a better standard of evidence than I see from many marketing teams, but it isn't the highest standard of evidence.

It is worth noting that helix's product can be used in things like road pavement, where rebar reinforcement is not an option. It can also be used in combination with traditional rebar reinforcement.

Conclusion

From their evidence and a careful read of their claims, TSMR reinforced concrete is definitely stronger than plain concrete. If it is combined with traditional rebar, it can be stronger than rebar alone. Helix does not claim that it will ever replace traditional rebar completely.

This is just a form of steel fibre reinforced concrete (SFRC) with twisted fibers. SFRC in general has been around since 1874. It's also been heavily research for at least 50 years (previous source and the last in this answer say this.)

Twisted fibers are slightly better than other kinds in some respects, but not by much. (There's no point in getting into details on this here.)

As for replacing rebar, a more introductory 2018 academic presentation, which is aware of twisted fibers (has photos among the showcased types), has these general points about SFRC in general:

• The addition of fibres enhances the structural performance of plain concrete (much higher fracture energy)


• Fibres reduce the crack spacing and crack width, thereby improving serviceability and durability


• Currently used SFRC mixes exhibit a softening behaviour in tension and cannot fully replace conventional reinforcement


• Hybrid reinforcement (fibres and conventional reinforcing bars) can be used, but may affect ductility

So, SFRC is clearly not a replacement for rebar in general. And these bits are also relevant:

Several causes are preventing a more widespread use of SFRC:

• Lack of standardised design procedures and material test procedures




• High fibre contents (e.g. 1.5% = 120 kg/m3) as required for structural applications (and used in many experiments) are causing severe problems in terms of mixing and workability of concrete mix




• With common fibre contents (e.g. 0.5% = 40 kg/m3), the tensile strength of concrete cannot be matched at cracking

Since this is written by a (Swiss) professor in this field, I'd be amazed if he hadn't hear of some amazing breakthrough in this respect (in particular for products already commercialized.)

And if that's not enough, he repeats again:

For general application in engineering practice, it is necessary to
include conventional reinforcement in combination with SFRC to
ensure structural safety and an adequate crack distribution.

As far as the particular cited manufacturer goes, Helix Steel actually publishes a "conversion" table which states the equivalent preparation of concrete with their product as for rebar. This has an licensed engineer's stamp on it (1) and cites several building codes.

As noted in the other answers I also would tend to trust independent verification not to mention long-term field experience of professionals more than the company's own claims. But they do have their reputation at stake with this material so it seems to be at least a good starting point for further evaluation.

In the Helix Conversion section of the document they state or imply that it is the "the ratio of area of steel reinforcement to the gross area of concrete" which confers the overall structural properties important for certain reinforced concrete applications. This appears to be the basis of the equivalencies claimed in the table.

As far as it goes IMO it seems reasonable to me that if you match the overall cross-sectional area of steel in a given direction, then the micro-rebar is also going to have a much greater contact area with the concrete, and the resulting reinforced concrete material could be quite strong as a result. At least, this seems to be something like what their analysis is saying.

Also it is worth noting that some of the other claimed benefits of the micro rebar are not structural properties but "ease of use". So even if you had to over-specify the concrete mix to build in an extra engineering "safety factor" to compensate for unknowns of working with the material, you might come out ahead in terms of build time or costs. That seems to be part of the potential appeal.

(1) The engineer in question does appear to be affiliated with Helix Steel. So stamping the report may not be putting his credibility on the line any further than his own job entails anyway.