“We did some patch work on concrete but it always comes off” - This is the most common problem statement that we keep hearing.

It is even more prominent in factories and warehouses - due to high frequency of movements.

Factory managers experiment with a wide range of materials like - Plain Concrete, GP2 cement, Epoxy based fillers, some even used bitumen.

However, nothing seems to work!

There is also confusion on - “we filled all potholes with the same material - some of them are still intact but some have come off”.

Hope this article would answer all such confusions on pothole repair.

The general notion is that the filler material is solely responsible for longevity of pothole repair.

That is just not true!

Below are five major reasons that lead to failing of repairs and how to deal with them to get long lasting results.

Reason # 1: Shape of the Pothole

In the above image, you can see the cross section of a concrete pothole.

#1 is a potholes with smooth and flat edges. It is not able to retain the filler material. Whereas, #2 is a pothole with sharp “v” shaped edges. It retains the filler materials strongly.

Due to the flat and smooth edges in #1 - the filler material tends to erode from the edges. In the process, the pothole not just loses its filling material but also becomes wider.

We need to re-shape the edges with chisel and hammer to get the desired shape. Do not worry if in the process of reshaping it becomes deeper - its not a problem.

Reason # 2: Level of Filling

The general practice is to fill the potholes - exactly to the ground level. At first this appears to be the most logical thing to do. However, we forget about one small phenomena - “shrinkage”

If we fill just at ground level, it will shrink and sink below ground level by a few millimeters, leaving a shallow crater on the floor that may not be visible to the naked eye.

This crater creates an uneven surface for ground operations. For instance, forklifts moving over this surface will encounter bumps, leading to potential future damage.

However, if we fill above ground level, even if it remains elevated after drying, It can be levelled right to the ground level by grinding.

Reason # 3: Inadequate surface preparation

No matter how good the filler material is, if there is loose material at its base, it will never work!

Assuming that reshaping of edges is already done, please follow these steps for surface preparation:

Step 1: Cleaning

Remove all loose material from the pothole. Also, check if there is a weak surface on the pothole floor. If yes, then break it and remove all material (don't worry about the pothole becoming deeper). Reshape the edges if needed after this step.

Clean the pothole thoroughly.

Step 2: Drying

The pothole should not be wet while filling. Water dilutes the filling material and also creates a false volume for the filling material.

Step 3: Coating with a bonding agent

If filling with concrete-based filler, apply a very thin layer of an old-to-new bonding agent with a brush on the pothole surface. Remember, it should be a thin layer and not a puddle of the bonding agent. Nito bond works well as an old-to-new bonding agent.

Reason # 4: No bonding of Old and New Concrete

Concrete is very much like humans - the new generation doesn't bond well with the old generation. Thus, if concrete is directly poured on the potholes - it will surely come off in some time.

The solution?

Old to new concrete bonding agents. These chemicals bond well with both - old and new concrete. Thus helps to keep them together. We at Rezovate, generally use Nito Bond for this purpose and it has never disappointed us.

Reason # 5: Incorrect combination of Width - Depth - Filler material

Even though deep potholes look scary but they are easiest to fill. The shallow potholes - though look harmless, but are not able to retain the filler material.

But by deciding the correct filler material as per width and depth of the pothole - we can achieve a long term solution for both.

At Rezovate, we decide on the filler materials as per the depth and width of the pothole. Here are a few examples:

• Epoxy based fillers for very shallow potholes (< 2 mm)

• Cement mixed with Nito bond for potholes that are 2- 5 mm deep

• Mixture of Cement, Sand and Nito bond for 5-10 mm deep

• Mixture of Cement, Sand, 10mm aggregate, PP Fiber and Nito Bond for 10-15 mm deep

• Micro-concrete with PP fiber for depth > 15 mm

• If the width of a pothole is > 30 inches then we also use reinforcement (either PP mesh or thin GFRP bars depending on the size)

Concrete repair can be tricky, but if done right, then it gives long lasting results. Hope this article helped you in understanding the process. Even now if there is a difficult floor situation, please write to us with its pictures and dimensions at info@rezovate.com. Our experts would be happy to help.