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You can put new concrete over old concrete. However, unresolved issues with your old concrete, such as cracks or frost heaves, will carry over to your new concrete if not taken care of. In addition, you must pour it at least 2 inches thick.
How do you attach concrete to old concrete?
Drill 5/8-inch diameter holes six inches deep into the old concrete. Flush the holes with water. Inject epoxy into the backs of the holes. Insert 12-inch lengths of rebar into the holes, twisting them to ensure an even coating of epoxy around their circumferences and along their lengths within the holes.
Does concrete stick to concrete?
The cement within a concrete mix doesn’t contain any natural bonding agents – so when fresh concrete is added on top of an existing layer of concrete, the two won’t join together. Once cured, the new concrete will simply sit on top as a separate layer.
What happens if you pour concrete over concrete?
You can pour as thin as 1.5 inches over the old concrete. The smallest rock size is about 3/8 inch. If you pour any thinner than 1.5 inches you don’t have enough cement paste over and around the aggregate to get strong concrete. It’ll end up cracking and breaking off if you pour it too thin.
What do you use to bond concrete to concrete?
QUIKRETE® Concrete Bonding Adhesive (No. 9902) permanently bonds new concrete, plaster, and stucco to existing concrete, plaster, and stucco. Eliminates the need for roughing the surface before the application.
Which concrete has well bond with old concrete?
There is nothing in basic portland cement that will act as a bonding agent. Portland cement concrete works well in mass and provides great compressive strength but not bond. Concrete is marvelous stuff but in time it will deteriorate. When it does, you either have to patch it or replace it.
What is poor man’s concrete?
We have a few companies locally that offer “poor man’s concrete”. I’m not sure exactly what it is, but I’ve seen it in driveways and such. It’s a white powdery material they dump and flatten out and when it gets wet, it’s supposed to harden like cement.
Can I pour a 2 inch concrete slab?
If done properly, new concrete can often be poured right over an existing slab. For this to be feasible, the contractor needs to pour at least 2 inches thick, use smaller aggregate, and incorporate reinforcement such as welded wire mesh or fiber mixed into the concrete.
Can I pour concrete over dirt?
Long story short, yes you can pour concrete over dirt.
Do you need rebar for concrete patio?
Do concrete patios need rebar? Even though it’s possible to build a concrete patio without rebar, it’s not recommended. All concrete is subject to cracks, but rebar holds all the cracks together and keeps the slab level and even. Without rebar, the cracks would become quite wide and the concrete would become uneven.
Does Loctite work on concrete?
Loctite Epoxy Metal/Concrete is a two-part system consisting of an epoxy resin and a hardener. When mixed in equal volumes, resin and hardener react to produce a tough, rigid, high strength bond in 5 to 12 minutes. It is used as an adhesive for repairing, filling and rebuilding all metal and concrete surfaces.
Does epoxy bond to concrete?
Most epoxy glues for concrete come as two-part systems consisting of an epoxy resin and a hardener. When equal volumes of the resin and hardener are mixed, they react to produce a tough, rigid, high-strength bond. You can use epoxy resin for concrete to repair, fill, bond, and rebuild concrete surfaces.
What are the alternatives to concrete?
We have collated 11 green building materials that offer alternatives to concrete, and a lower environmental impact. Straw Bales. Grasscrete. Rammed Earth. HempCrete. Bamboo. Recycled Plastic. Wood. Mycelium.
What is a good substitute for concrete?
Concrete: Cement Substitutes Pulverised Fuel Ash (PFA), aka ‘Fly ash’ as a cement substitute. PFA is a by-product of coal-burning power stations. Ground Granulated Blast-furnace Slag (GGBS) as a cement substitute. GGBS is a by-product of the iron and steel industry. Silica fume. Limestone fines. Alternative fuels.
What is the cheapest way to make concrete?
One of the least expensive ways to get concrete is to mix your own. You can buy bags of the mix from a home improvement store. Typically, you only have to add water for it to be ready to pour. However, it is important to get the ratio right and to mix the concrete thoroughly.
How strong is 6 inches of concrete?
For example, a 6-inch pad with a compression strength of 700 psi can support 1,105 psi. If it was 7 inches thick, it could support 1,194 psi, and if it was 12-inches thick, it could support 1,563 psi.
Is 2 inches of concrete enough?
A: Concrete is typically applied at a thickness of 2 inches or more, but the thicker it is, the stronger the slab will be. Four inches is most common for a slab. Products labeled “High Strength Concrete Mix” are ideal for these types of applications.
How long does it take for 2 inches of concrete to dry?
Concrete typically takes 24 to 48 hours to dry enough for you to walk or drive on it. However, concrete drying is a continuous and fluid event, and usually reaches its full effective strength after about 28 days.
Do I need gravel under concrete?
Whether you pour concrete for a walkway or patio, a strong gravel base is required to prevent the concrete from cracking and shifting. Gravel is especially important in clay soil because it doesn’t drain well, which results in water pooling under the concrete slab and slowly eroding the soil as it finally drains.
Can I use pea gravel under concrete?
Your concrete will crack, guaranteed. But a good rigid and compacted base will keep the individual mini-continents from shifting. The concrete doesn’t need to adhere to the stone base, there is no advantage to that. If your going to use pea gravel, in my opinion, your wasting time and money.
What kind of gravel goes under concrete?
Most concrete contractors want a mix of coarse and fine aggregate to create a compactable base that is going to be safe for settlement and drainage. Crusher run (a mix of crushed stone and stone dust) is one of the best base materials for concrete flatwork.
