Comparing stress-strain curves from different methodologies

[keno.mentor]

I am a medical researcher with little physics background but currently completing a study of the physical characteristics of arteries.

I am trying to compare the stress-strain curve from my study with that of other studies. The problems are 1) the dimensions of the arteries in these other studies are slightly different from mine and 2) the methodology is different.
Can the stress-strain curves be compared? Does the calculation of stress (in KPa) and strain (dimensionless) take these differences into account such that these curves are comparable?

To elaborate:
I derived a S-S curve by circumferential stretch of a 1cm segment of 5mm diameter tube.
The comparable study took a 10cm segment of 4mm diameter tube, tied off the one end and subjected it to increasing fluid pressure. Is it reasonable to compare the S-S curves (and Young's moduli) derived from these 2 studies and make a general statement of how these 2 materials differ or are similar?

 

[Kevin McHugh]

This is precisely why there are ASTM methods for testing materials. Google the ASTM method, and then look at the methodologies for the two cases compared to the ASTM method. If everything seems reasonable, then you can probably be safe to compare data.

 

[keno.mentor]

Thanks for the reply Kevin.

I haven't been able to find anything that helps me though - ASTM standards is a bit of a rabbit hole and most of the articles need to be paid for.

Unless you can point me to a specific reference or document?

 

[Nidum]

Ideally repeat both experiments and come to a definite conclusion .

Otherwise do a proper stress analysis of both test samples .

Hand calculation would probably give adequate results .

FEA would not be too difficult if you wanted more sophistication .

 

[keno.mentor]

Thanks Nidum.

To clarify: I am testing an artificial artery, which I am analysing in the way I described above (circumferential stretch). I am trying to compare this data to another group's study, which tested a 'natural' artery with burst pressure testing.

Could you expand on 'FE models'?

 

[Nidum]

FEA is a very powerful tool for analysing technical problems .

Some images of FEA models

Example of medical use

ANSYS Home

ANSYS Mitral Valve

 

[Nidum]

http://www.ansys.com/-/media/Ansys/corporate/images/about/magazine/AA-V1-I1-Full-Version.pdf