How do I hand mix small batches of concrete that will stand up to freezing temperatures. Please note I will be pouring this concrete during the warm summer months but it will be placed outdoors and exposed to freezing temperatures long after it has cured. I have heard that I need air-entrainment agents but have also been told that it is almost impossible to accurately measure out the admix for very small batches. Too much weakens the concrete, too little does no good. By small batches I mean about 2 gallons of sand/aggregate + the cement and water; I don't know that the little mixer I have will handle much more. Any suggestions will be appreciated. Possibly a departure from the usual 1:3:3 mix. Thanks

Hello! I was debating putting this in recreation - But at its foundation this is really a question about bricks and mortar. I desire to create a brick oven.. Going to try and save up to use firebricks for the base, but hoping to stick with regular red clay bricks for the dome. (It's a cost thing!) Along the same thoughts on savings.. Is it possible to create a dome structure out of red brick chips and high heat mortar? Or, will I end up with more mortar than brick, making it unstable and useless? The thinking here is that I can get a bunch of broken up brick next to nothing, and mix it with the mortar and put it over a mold and let it dry. Thoughts? Joe