What’s on this page:
- How long before I can park on my new driveway?
- How long before my new driveway is usable?
- How does hot weather effect concrete curing?
- If the temperature of the concrete at the time of concrete placement will exceed 77 degrees Fahrenheit, a plan should be developed to negate the effects of high temperatures.
- How long does a concrete driveway take to cure and what is the best method
- If I drive on the slab prior to joints being cut am I more likely to damage it?
Is it really OK to drive on the concrete after only 2 days? My neighbor just had a new driveway installed this week and he came over to my place to ask me this question. I know I should have said to him that the concrete guys that installed it should have told him but no one did so this is my take on the time a concrete drive needs to cure before you should drive on it.
So how long should you wait before driving on a brand new concrete driveway? This will depend on two things thickness of the concrete and the weight of the vehicle being driven on it assuming that the concrete and reinforcement steel is installed correctly. But 48 hrs is not good. ” High Early strength” cement reaches 50% of minimum strength after 7 days ( I think at 70 F about 21 C, longer at lower temperatures). You can check at the Portland Cement Association site. Cement gets stronger for a long ( years) time. Initial compaction ( like vibration) improves the final strength. It is good to keep the surface damp for a couple days after pouring. I would say rebar is necessary for truck traffic mesh is ok if the mesh is design for the extra load.
Even if control joints were cut, the concrete is at a fraction of its ultimate strength (maybe 15-30%, depending on several factors). You run a high risk of breaking it at other locations usually along the edge of the driveway.
Before I answer the question this is the main reason I see concrete slabs failing
One of the biggest mistakes that I have seen in pouring new concrete driveways is that the reinforcement mesh is not lifted into the middle of the concrete. Having the wire at the bottom of the slab is worthless.
They are supposed to pull it up to the middle as they place the concrete. It will not provide any strength at all at the bottom.
If it is at the bottom all over you have a huge problem. Even if the mesh was properly pulled up into the center line of the slab thickness it is really a minimal technique. A good driveway slab installation would also have a grid or re-bar installed into it.
You should search around the edges of the whole slab to see how much more evidence you can find of “mesh at the bottom”. If there is then you need to get the contractor out there to remove this botched job and install the slab properly.
How long before I can park on my new driveway?
Will the slab further strengthen by in the order of 25% over the next 12 hours?
Maybe, but that’s 25% of the current cure extent, which could still be a minor fraction of the ultimate strength. Cure rates depend on many things, from mix to water content to weather to
If you drive over concrete which is still in the early stages of curing/setting and it doesn’t visibly crack, am I weakening the eventual strength of the concrete?
Cracks due to vehicle traffic are usually apparent right away, but it is possible that you’ll crack it and not know it until dirt starts to accumulate on the line or it opens further.
If I drive over concrete which is still in the early stages of curing/setting and it doesn’t visibly crack, am I weakening the eventual strength of the concrete?
If you drive over concrete in the early stages of curing/setting and it doesn’t visibly crack, you are weakening the eventual strength of the concrete.
Cracks due to vehicle traffic are usually apparent right away, but it is possible that you’ll crack it and not know it until dirt starts to accumulate on the line or it opens further. If it doesn’t crack, it’s probably not weakened in any substantial way.
How long before my new driveway is usable?
For the First Two Days – Although your new concrete will become solid fairly quickly, it has little strength and hardness for the first two days. During that time, especially during the first 24 hours, keep all traffic off the concrete. I have written about concrete curing to stop it cracking this is a link to the article on how to cure concrete for extra hardness.
Any damage to the surface of the concrete will be permanent. That means adults, children, and pets, too. Put up warning tape, but once the concreters have left the work site is up to you to keep children and pets off the driveway because they are attracted to your new concrete slab, so be sure to ask your neighbors to keep their children and pets off the fresh concrete. Many concrete projects end up with footprints of children and pets if this is ignored. For the first few hours, this is even more critical. Many homeowners keep a constant eye on their project during this time. Falling leaves, tree sap, and wild animals like squirrels, crows, and other birds can also scar the surface, especially in the first 24 hours.
For the Rest of the First Week – After two days, you can feel free to walk on your new concrete. It’s tough enough at that time to resist scars from walking. However, avoid twisting or skidding shoes on the concrete during that time, and keep bicycles, skateboards, and other toys off the surface. Do not drive on the concrete for the first 7 days. Leave the warning tape in place to let delivery vehicles and others know that they need to stay off your concrete.
After One Week – After 7 days, it’s OK to drive on your new concrete with normal passenger vehicles. Avoid driving near or across the edges of the driveway, though, since those areas are still weaker. Also, avoid skidding things on the driveway or dragging sharp objects on the driveway, since they can still scar the surface.
After 30 Days – When 30 days have passed, your new concrete will have developed almost all the hardness and strength it will have, and you can use it in any normal way. You should avoid allowing heavy trucks, like garbage trucks or moving vans, on your residential driveway. It’s not designed for that kind of load. After 30 days, the curing agent applied to your driveway will have dissipated, so that’s a good time to apply a concrete sealant for the first time. I have been asked about driving an RV on a new concrete driveway so I wrote this piece about it.
How does hot weather effect concrete curing?
Pouring concrete in hot weather could present the following problems:
Hot weather isn’t a general term when talking about pouring aconcrete slab. Hot weather is defined as high ambient temperatures above 90 degrees Fahrenheit, low relative humidity and/or high wind speeds. That’s correct, hot weather isn’t just air temperature. In certain areas, hot weather can be
Increased difficulty when finishing the concrete
The formation of cold joints due to hot weather decreasing the setting time
Reduced strength and durability
Lower compression strength
Additional drying shrinkage of the hardened concrete
Increased risk of cracking
If the temperature of the concrete at the time of concrete placement will exceed 77 degrees Fahrenheit, a plan should be developed to negate the effects of high temperatures.
Have sufficient manpower to manage the concrete when it is being poured and for the finishing process best to have plenty of manpower so that you get the concrete can be installed quickly.
If possible, avoid pouring concrete at noon or during peak times for hot air temperature early in the morning is best before it gets too hot.
When pouring concrete in hot weather, space control joints at smaller intervals than cold weather concrete joints.
Use some sort of windbreak and sunshades to protect the concrete from going hard too quickly.
Plan to haveindoor slabspoured after all walls and roofs are built.
When pouring concrete in hot weather keep a water hose onsite in case temperature gets hotter and water is rapidly evaporating.
Wet the ground that the concrete is being poured onto and wet all the formwork and the tools that are being used to place the concrete
Reduce the mixing time once water has been added to the mix
Implement the correctcuring methodto allow the concrete to set uniformly like keeping the concrete either moist or covered to slow the curing process and make it a lot harder and less absorbent
I know I have deviated from the topic but it is because if you can cure concrete correctly there should little or no cracking and that means a driveway that is stronger and easier to maintain for years to come.
How long does a concrete driveway take to cure and what is the best method
This is the question I am asked a lot and my method is as simple as using a garden hose to wet the surface at least twice a day and if it is very hot I like to cover the concrete after wetting it using plastic or something to keep the surface from drying too quickly.
If I drive on the slab prior to joints being cut am I more likely to damage it?
No, but it is more likely that you’ll end up with crooked (uncontrolled) cracks, which are ugly.
