...generally available.
Covid has made access even more difficult, since many academic libraries have greatly restricted public access.
Fortunately for me I'm managing with some limitations compared to what I enjoyed previously.
Over the years here at DU I have worked to comment on papers my broad access allowed, often writing in some detail, sometimes with more success than other times. For me it's been mostly an exercise in teaching myself things, often with the supplementary goal of confronting some unfortunate ideas prevalent on our side of the political spectrum that border on dogma.
The greatest threat to the future, to my mind, is climate change, and while we say it is important to us, my feeling is that we really don't get it on the left as well as many of us seem to think.
In this process of researching posts intended for here, as well as far more extensive reading well beyond what I cover here, I have developed some very different perspectives with which I expected to die. These ideas are frankly, way "out of the box" and I am unashamed to say so.
Recently my son chose - I swear I had nothing to do with it - to pursue his Ph.D. in nuclear engineering. (He is a Master's level materials science engineer.) He has told me that some of the ideas I've shared with him strike him as worth saving, and so I am stepping back a bit from the elaborate posts I write here to write elaborate notes for him. I owe this to him, and perhaps, in the case I am right, not to be overly arrogant, to the world, through him. I cannot leave him with a lot of money, but I can leave him ideas.
Some of the posts I've written here have taken an enormous amount of time to compose. Again the idea was to teach myself, but now I am running out of time on the planet. I really feel my mortality now. I now need to spend this time sharing ideas with my son. He's filling me with questions, excellent questions, asking for leads, and understanding that his old man actually knows something worth knowing, while bringing his advanced insight to materials science to bear on questions I have asked myself but have been unable to answer.
I wish I could discuss the details of this interesting line of research to which I referred in the opening post here as I did in the old days; there is much that may be addressed in the problem of plastics, and in the problem of closed carbon cycles through radiation.
However I can't. There isn't time.
To briefly answer your questions:
The goal sought here is to reduce the carbon impact of concrete by displacing volume and mass. You are correct that the mechanism is crosslinking. Compressive strength was evaluated with ASTM method c39 and it was found that irradiation of plastic at 10 kGy and 100 kGy increased the compressive strength relative to concrete containing unirradiated plastic as a filler. The improvement at 100 kGy was on the order of less than 10 MPa improvement in compressive strength relative to untreated plastic filler.
There is less strength than various formulations lacking plastic at all, but again, the carbon impact of the concrete is much lower, so the advantage is not necessarily in strength but rather in sustainability.
Concrete production is a major contributor to climate change, which is another reason low energy to mass ratios in energy systems are not sustainable.
The concrete prepared for this paper has been studied with a very advanced technique, X-Ray Microtomography, using the advanced photon source at Argonne National laboratory. The strength increases relate to reduced porosity.
I hope this helps.
Don't disparage what you do. It seems to me that a high school science teacher has one of the most critical jobs in the world.
I wish you a happy holiday season and a rewarding New Year.
= new reply since forum marked as read
