Denver Decorative Concrete & Custom MasonryWhen I pour my concrete driveway in sixteen x eight sections, what should I do to attatch the next section?
I plan on making block ends after each section. I’m wondering how to join each section. Should I just have twenty four inch pieces of rebar inserted twelve inches into the poured section through the block end, with the other twelve inches sticking out the other side of the block end, waiting for the next pour? Do you recommend making a tongue and grove type of joint in the cement? I like the rebar idea the best. Would I have to put expansion joints between each section also, or could I just make my control cut there, with no expansion joint? I want to make sure the sections all stay even with each other, without separating.
all correct go as planned.
tongue and groove with cement (concrete) is a bad idea. Why? the top of the groove will break very easily.
For joining the brand new section the rebar sounds good. Also, they sell a white milky liquid that is made for joining brand new concrete to old concrete.
For a 16×8 section you need expansion joints. Go to the cement store and ask the guy what that means. (It’s cheap.)
A cold joint in your concrete will be fine, and the rebar to keep each pad even is a good idea***, I’ve always used wire fencing mats pulling them up into the concrete, and kept them short of the edges. Relying on a good base to prevent uneven heaving( think of sidewalks—they are not joined together and usually only heave unevenly when forced up by a tree root). (i have no idea what the block ends are)
***The only problem with rebar joining the pads are time and corrosion—where the rebar sticks out from the concrete and spans the tiny crack between each pad, air and moisture will combine with the lime in the cement and rust the rebar, in time it will rust, expand, and crack your concrete. This is why when you see highway crews using rebar it is greenish in color, this is a special coating that protects it from rusting. It still does over time-adding salt to the roads in the New York winters speeds up this process. If you look closely at concrete road/highway potholes you’ll almost always see a rust stain on the concrete first and around the recently forming hole.
If you decide on this method,(personally, I would not or have not) anything you can do to that small area of rebar that sticks in the crack between pours that will fend off rusting a very little longer is also a good idea.
ANSWER DELETED
In that I only get 1 vote, and the ASKER wants the voters to select the best answer, my answer was deleted. I’m tired of answering and having completely incorrect responses supported by fan clubs selected by the VOTERS as best answer. It just is not in the spirit of what I thought this site was all about.
For all the reasons and details provided, and deleted, rebar won’t work and actually will result in significant damage. By the way alternates and solutions were provided, and deleted, which would have solved your issues.