If you have a concrete slab like a driveway or a garage floor or even a side walk,chances are it will eventually sink or crack but you might not have to replace it.We will learn an intresting method of Concrete Leveling.
Here we are taking an example of Concrete Leveling a garage floor and driveway,our driveway is settled down and what is happening is water is pulling there whenever it rains which in winter can cause issues with ice so main concern there is getting kind of pitch away from the driveway and back into the street to alleviate that some of that icing up issues
Our second problem is having the piece of concrete settled down and providing uneven surface so we will show you how to solve these two problems with concrete leveling that will remove cracks and all uneven surfaces.
So the process we are going to use is called Poly Level what that is,is a polyurethane foam that we inject underneath a concrete that expands and it actually raises the concrete from underneath it’s not a long process at all the job we are going to do roughly takes about 2 to 4 hours and it takes only two men crew,one guy runs the gun the other guy drills holes puts the ports and cleans up behind the first guy.
Here some of you will do Mud Jacking which is actually a real similar process the difference with it is we are using actual poly urethane foam as opposed to injecting more concrete underneath your existing concrete,mud jacking they come in they drill holes about 4 inch big and holes in poly level are the size of a penny.Mud jackers when they inject more concrete underneath that weighs about 150 punds per cubic foot while poly level process weighs only 4 pounds per cubic foot so in poly level its does not tend to settle down because we are not injecting more weight.
This is a process that can be used for all concrete that need to be stabilized and leveling sideways,driveways,garage floors,porches,patios etc anywhere there is concrete you can level it by this process.You can use this process without replacing entire floor or slab and this is cheap.
What Actually Causes Concrete To Actually Sink And Crack?
There are a lot of factors that go into that the important one is Shrinkage,we know concrete is weak in tensile strength and strong in compressive when concrete sets it shrinks because of evaporation of water.In order to get crack free concrete we should mentain proper water cement ratio.Excess of water can cause cracks.
if we are constructing a pathway we should always give it a slope towards drainage so that water will not accumulate at any place as it can cause cracks due to frost action.
The important point we have to keep in mind while casting concrete is that soil should be well compacted before laying of concrete as loose soil can settle down which will make concrete to sink and will create cracks on it.
So question here is how can we compact soil?
well there are two methods i will suggest you one is either go for excavation untill hard soil comes out and lay concrete on it or use soil compactor which will charge you few extra bucks than the later one.Excavating soil is the best option i will prefer.
Is it normal for concrete to crack?
whenever concrete shows a crack it means something wrong has been done while laying it.There can be several reasons
- Soil on which concrete has to be lay down is not well compacted.
- Improper Aggregate Size
- Excess water may have been used
- Vibrator for concrete compaction have not been used or have completely ignored
- Shuttering supports may not have been used or they may have been loose
- Improper levelling
- Unskilled labour
what is the setting time of concrete?
It depends on the type of work,concrete ratio,temperature.If we are using M20 ratio that is 1 part cement 1.5 parts sand and 3 parts aggregate.It usually takes 24 to 48 hours based on indian onservations.
How To Do Concrete Leveling and Finishing Of A Floor?
if your concrete floor surface is uneven it’s worth spending some time to get rid of any dips and imperfections.A floor leveling compound will produce a smooth and even surface on which you can light your smart new floor covering.It’s quite easy to do if you have the right tools and equipment and follow the right process.So here is the guide that will walk through you leveling a concrete floor.
- Give the floor thorough sweep to remove any dirt and dust,befor sweeping dampen the area using spray bottle this will help to keep the dust down,don’t use domestic vaccum as it may get damaged by concrete dust.
- Inspect the floor to see if any repairs are needed and check for any grease or oil on the surface and remove it.
- Most standard floor leveling compounds can be applied up to a maximum of 5mm to 6mm in thickness but some products provide greater thicknesses.So always check manufacturer’s instructions
- If any holes,dips or cracks in the floor are deeper than maximum thickness that the leveling compound can be applied to.You have to repair them with suitable concrete repair
- You can check how deep is the dip on floor by placing a spirit level across the floor area and measuring from the bottom of the level to the bottom of the hole or dip a steel rule which is much better than a tape measurement
- Check if the floor has slight slope it has the leveling compound will have a different thickness in different parts of the room.You can work out the average thickness and by the correct quantity of leveling compound.
- Lay your spirit level on the floor if it reads level all is good if not then lift the low end until it reads level.
- Measure the gap between the bottom of spirit level and the floor.We can easily calculate the amount of slope over the length of the level.
- If the slope is across the whole floor use water level
- Now if you are happy the floor is ready for leveling seal the surface with a diluted PVA adhesive mix or suitable acrylic primer using paintbrush
- Once the primer is dry work out how much leveling compound is going to be use
- So with this guide a Concrete floor can be leveled