All thread rod as rebar

[Streetcar]

Galvanized or coated I would say no. Rebar is bare, uncoated steel for a number of reasons.

Most rebar is uncoated because that is the cheapest

 

[Streetcar]

I've been in construction inspection for 40 years.

Rebar is high carbon, graded and generally at least 40 grade usually 60 grade. (Very hard, very strong). All thread can come in different grades, but generally the off-the-shelf stuff is mild steel, same as a grade 2 bolt (different grading system).

While using this in your concrete won't do any harm, it won't replace rebar for adding additional strength. In other words. If you need rebar, use rebar as well.

Mild steel is just weaker rebar, the high end all thread is stronger rebar. I have repaired bridge piers using all thread as the reinforcement by design

 

[etpm]

Galvanized or coated I would say no. Rebar is bare, uncoated steel for a number of reasons.

I don't know why rebar is uncoated, mostly, but apparently galvanized steel is fine in concrete. I looked into this a while back because I have some 4 x 4 x 1/4 galvanized fencing, I think it is called hog fencing, that is excess to needs and I thought it might be good to add to a concrete pour. And the question about galvanized steel was answered in the positive. As I recall the alkaline environment of concrete is fine for zinc coated steel, it's acidic environments that attack zinc.
Eric

 

[yanmars]

I should have indicated what I plan to do. Have a lean to (15x40 feet) on an ag building. Would like to pour concrete in it as a floor, enclose the same so I can put in a toilet, shower and sink so I can clean up after working. The plan is to have 2 inches of concrete rigid foam, water vapor barrier and 4 inches of concrete. This pour would be drilled and pinned to the ag building concrete so no settling. No weight on the same except for foot traffic.
Just felt for such a light load the all thread rod would be sufficient.

 

[Rockbadchild]

''Concrete Alkalinity: Concrete is highly alkaline, with a pH typically ranging from 12 to 13. While galvanized steel generally has good resistance to alkaline environments, there is a possibility of the alkalinity of the concrete gradually degrading the zinc coating over time. This degradation can be influenced by factors such as the concrete's pH, moisture content, and temperature. However, in many cases, the corrosion protection provided by galvanizing is sufficient for the intended service life of the structure.''

''In summary, galvanized steel can be used in concrete structures where corrosion resistance is important. However, it is essential to ensure proper surface preparation, sufficient concrete cover, and consider factors such as alkalinity and compatibility with concrete additives. Consulting with structural engineers, galvanizing specialists, or concrete experts can provide more specific guidance based on the project requirements and conditions.''

 

[Gem99ultra]

I should have indicated what I plan to do. Have a lean to (15x40 feet) on an ag building. Would like to pour concrete in it as a floor, enclose the same so I can put in a toilet, shower and sink so I can clean up after working. The plan is to have 2 inches of concrete rigid foam, water vapor barrier and 4 inches of concrete. This pour would be drilled and pinned to the ag building concrete so no settling. No weight on the same except for foot traffic.
Just felt for such a light load the all thread rod would be sufficient.

I wouldn't hesitate for a minute using the all-thread. I bet it'll be stronger than the chicken-wire, and other trash metals that I've used in the past. Foot traffic and shower, etc. isn't going to come anywhere near enough weight to break your 4" of concrete slab.

 

[Shenandoah MF1760]

I've used 3' all thread with muffler clamps to anchor swing sets, works better than concrete. Makes good tent stakes too. The threads provide gripping you wouldn't get with rebar.

For concrete work, I wouldn't hesitate to use scrap all thread.

 

[olenjohn]

I should have been more specific. This is for a slab pour that will be inside and really have nothing heavy on it.

For an inside slab pour with very little load, you are wasting the thread rod and your time putting it in. Sell or use the thread rod for other purposes. Fiber reinforced redimix will work just fine for your floor. Never use the thread rod for an elevated slab reinforcement. 40 years in construction / engineering industry so I might just happen to know something about it.

 

[not2old]

Didn't know you weren't supposed to weld rebar. I thought I'd seen it done on some very large posts/piers on TV. Only done it when making my own concrete railway ties for a retaining wall so I won't worry about it.

 

[Streetcar]

I should have indicated what I plan to do. Have a lean to (15x40 feet) on an ag building. Would like to pour concrete in it as a floor, enclose the same so I can put in a toilet, shower and sink so I can clean up after working. The plan is to have 2 inches of concrete rigid foam, water vapor barrier and 4 inches of concrete. This pour would be drilled and pinned to the ag building concrete so no settling. No weight on the same except for foot traffic.
Just felt for such a light load the all thread rod would be sufficient.

Four inch thickness will be hard to get any practical use from reinforcing steel except as crack control

 

[Streetcar]

Didn't know you weren't supposed to weld rebar. I thought I'd seen it done on some very large posts/piers on TV. Only done it when making my own concrete railway ties for a retaining wall so I won't worry about it.

Rebar is weldable. welding is used primarily on large diameter bars

 

[Sprinkler Fitter]

When I poured the 40x40 addition on my shop, I used cattle panels which I had on hand after we sold off all the stock for matting. Been in there over 10 years now and no cracks anywhere.

What is matting? To use it as a mat to walk on?

 

[5030]

cattle panels.

 

[Flogger]

Use it. Concrete will adhere to it just fine. I am known as captain overkill and I would not hesitate a second. Most people would be shocked to see what my Great grandfather used for reinforcement in some of the 100 year old concrete around here!!

 

[jigs_n_fixtures]

Rebar is weldable. welding is used primarily on large diameter bars

Some rebar might be weldable, but generally it isn’t. And whether it can be welded would highly dependent on where it is, and where the weld is in relation to the rest of the bar.

 

[5030]

Most rebar in new construction is wire tied together, not welded. Commercially made rebar is the lowest grade of recycled from scrap steel produced today so the chems can be just about anywhere.

 

[jigs_n_fixtures]

What is matting? To use it as a mat to walk on?

A layer of reinforcing steel is referred to as a mat. Depending on the purpose of the structure, and loads it is designed to withstand. A bridge structure may have so many mats, and so much steel in each mat that you have to be carefull of not get teh steel so close together that the larger aggregate in the concrete to pass between the steel.

Ideally reinforcing steel has a slight film of surface rust, not flakey rust but the fine surface rust. The micro-pits of the rust allows the cement paste to adhere more strongly to the steel.

Generally re-steel should be free of paint, oils, or anything else which could interfere with the adhesion of the concrete to the steel. Concrete has plenty of compressive strength, but little tensile strength and the steel is added to add tensile strength combination of concrete and steel.

 

[Cougsfan]

When I was a plant engineer the previous plant ownership had poured a elevated concrete deck in the plant. Before they poured it they apparently raided their bone yard and filled the forms full of old angle iron, pipe. scrap metal, wire and whatever else they could find. Not just a little, but a lot and it was put in in a very random fashion! Years later after we purchased the plant we decided that we had to replace that deck because it had developed a crack and vibrated rather noticeably from the equipment that was mounted on it. It was an obvious problem. We didn't know at that time that was how the deck had been built. When we saw what we had we realized that it was not only a serious safety concern; it was a legal liability as this re-inforcement method doesn't meet code. Demolishing that deck was an absolute nightmare! It had to be jackhammered into very small pieces. Metal had to be repeatedly cut with a cutting torch to remove chunks. It added more that a week to our project schedule. Bottom line; metal doesn't add strength to concrete unless it is put installed in a logical fashion.

 

[milkman636]

I built a steel frame building on poured walls about 18 months ago. The anchor bolts specified on the engineered drawings for each column were basically 12” long pieces of 1/2” threaded rod with a plate washer sandwiched between to heavy hex nuts imbedded 8” down into the foundation wall. A grand total of 60 galvanized threaded rods are holding the 40x60x12 building to the foundation. If the 24 in the picture below can take the shear of a 60’x12’ west facing wall and resist the uplift of the building, I think they are strong enough to reinforce a floor as well. But I’d probably want them galvanized or plated, or research an appropriate primer, and make sure I had the rod solidly embedded and not laying in the bottom of the slab.

 

[Streetcar]

Some rebar might be weldable, but generally it isn’t. And whether it can be welded would highly dependent on where it is, and where the weld is in relation to the rest of the bar.

Standard rebar is weldable. Some specialty rebar may not be weldable.
Loading of bar determines whether it should be welded or not