Very good testing. Thank you.
I believe this technique is called 'isochanvre' in France and goes way back, actually.
Also, I heard of a woman who built a house out of hempstalks she grew on site. She planted them in a circle and waited. She also planted extras. Then she bent them into a dome, tied them together, wove other hurds horizontally, and then plastered the whole thing with lime-crete. Beautiful! Sorry I couldn't find the link for that one. She was in the USA.
...But in this application the goal is a material that gives insulation as well as mass. For that you need the hurds.
Sorry for asking a dumb question, but where the heck do you get hemp hurds from?
I was thinking about insulating my outdoor worm hopper with mud plaster. Sounds like this would work as well and be more durable, as it's made from lime.
I would suggest avoiding putting organic fibers into concrete. If you must, please do long term trials before you build anything serious with it... For your own sake.
Do you think hempcrete would work in hyperadobe-style tubes? I was thinking post and beam frame with 'cretebag walls. Is it affordable?