Repairing Of Honeycombs In Concrete:
- First, remove the loosened aggregates and concrete particles from the affected surface by using a wire brush and a chipping hammer.
- Clean the surface thoroughly with a brush to remove finer particles and then wash the surface with water.
- Let the surface dry well and apply Chemi-fix glue on the area.
- Now mix the concrete grout with white cement and add the required amount of water ( as per the specification recommended by the manufacturer).
- Then pour/paste the mixture in the affected area to fill it completely. In case of large honeycomb, the concrete mixture should be poured after creating a pocket.
- Remove the formwork after 12 hours and then cure it well.
How do you remove honeycomb from concrete?
Remove loose concrete or loosened aggregate by hammer or wire brush. Prevent the application of large forces such as electrical chippers to avoid sound concrete damage around the honeycomb area. Clean any dirt or loose material from the area. Wet the cleaned area before applying the repair material.
What causes honeycombs in concrete?
Lack of compaction, leakage of grout, reinforcement congestion, etc. causes the honeycombs in concrete. Most of the honeycombs are discoverable as they occur close to the surface. However, in large structures, there are changes having created cavities that do not fill with concrete.
How to repair the honeycomb roof?
All types of honeycomb repair shall be rectified by using nonshrink construction grout and which has very very low volume reduction. When the size of the honeycomb becomes larger, special attention shall be made during the rectification. The following steps could be followed in the rectification process. Loads on the structural elements.
What is the best way to repair a concrete void?
In any case, good concrete repair practice calls for removing any loose material within the void. According to scientists, honeycomb often contains loose coarse aggregate if the void is caused by a leak in the form. If the void is caused by poor concrete consolidation; the coarse aggregates often are intact.
How do you fix honeycombing?
Isolate the affected area by removing layers of honeycombing until suitable concrete is exposed. Thoroughly clean the area to be repaired and remove all dirt and loose aggregate. Wet the cleaned area prior to applying non-shrink grout. Texture and colour should then be matched for aesthetic finish.
How do you repair a honeycomb wall?
Fill small voids and cracks using a mechanical injection pressure pump with a suitable material such as non-shrinkage epoxy grout. If the honeycomb covers a large area, you may need to create a patch hole to ensure proper bonding. Place formworks if necessary, and pour the grout.
What causes honeycomb in concrete?
Honeycombing is the term used to describe areas of the surface that are coarse and stony. It may be caused by insufficient fine material in the mix, perhaps due to incorrect aggregate grading or poor mixing.
How do you prevent honeycomb in column concrete?
Apply tape outside of the formwork with a wooden hammer during concrete pouring to reduce the risk of honeycombing. For column and beam junction, use a slightly higher water to cement ratio for concrete with a maximum aggregate size of 20 mm or smaller to decline the possibility of honeycombing.
What is honeycomb in concrete structure?
Honeycombs are hollow spaces and cavities left in concrete mass on the surface or inside the mass where concrete could not reach. These look like honey bees nest. Improper vibration and workability of concrete are main causes of honeycombs in concrete.
How do you fix honeycomb in concrete Quora?
Use a light chipping hammer (<7kg) to remove all the loosened coarse aggregates and mortar. Then use a brush to wipe off the remaining mortar. Follow this with sandblasting or water blasting followed by drying. Finally, just brush the surface once again.
Is honeycomb concrete bad?
In general, concrete honeycombing is considered a cosmetic condition that can only be found on the exterior areas of the concrete pour. However, if left untreated over a long period of time, moisture could penetrate the exposed areas. This could cause serious structural conditions, including concrete cancer.
How do you fix segregation in concrete?
In case of segregation, remixing for a short time may transform concrete again homogeneous. The concrete mix should be perfectly designed with best possible quantity of water i.e. not too wet nor too dry. The proportion of the mix should be correct.
What is honeycomb appearance?
Honeycombing or "honeycomb lung" is the radiological appearance seen with widespread fibrosis and is defined by the presence of small cystic spaces with irregularly thickened walls composed of fibrous tissue.
What is honeycomb formation?
Honeycombs are made from beeswax, a substance created by worker bees. When the temperature is right, worker bees secrete wax scales from special glands in their body. Then they chew the wax with a bit of honey and pollen to produce the beeswax.
What is the meaning of honeycomb in construction?
Honey combs can be simply be defined as a rough, pitted surface or voids in concrete resulting from incomplete filling of the concrete against the formwork, often caused by using concrete that is too stiff or by not vibrating it sufficiently after it has been poured.
What is concrete crazing?
Crazing is the development of a network of fine ran- dom cracks or fissures on the surface of concrete or mortar caused by shrinkage of the surface layer. These cracks are rarely more than 1/8 inch [3 mm] deep and are more noticeable on steel-troweled surfaces.
How can Honeycombing be avoided?
Avoid honeycombing by using appropriate concrete mixtures with sufficient workability, proper placement and consolidation techniques. Honeycomb, subsidence cracks, cold joints and excessive surface air voids are common surface blemishes associated with ineffective concrete consolidation.
What is Honeycombing in construction?
Honeycombing is a structural defect of a RCC Structure, areas of the concrete surface where the coarse aggregate are prominently visible are called honeycombed surface, giving a look of honey bees nest.
What is a concrete bonding agent?
Concrete bonding agents are natural or synthetic materials used to join the old and new concrete surfaces. This agent can also be used to join the successive concrete layers. This chemical helps to allow different concrete surfaces to behave like a single unit.
What is cement grouting?
Cementitious grouting is a process in which a fluid cementitious grout is pumped under pressure to fill forms, voids, and cracks. It can be used in several settings including bridges, marine applications, dams, and rock anchors. The grouted mass has an increased strength, stiffness, and reduced permeability.
Why is honeycomb loose?
According to scientists, honeycomb often contains loose coarse aggregate if the void is caused by a leak in the form. If the void is caused by poor concrete consolidation; the coarse aggregates often are intact.
How thick should a concrete void be?
Some agencies do not require a minimum thickness, while others set limits, such as 1 inch or 2 inches (25 mm to 50 mm).
How long to wait before applying mortar?
After placing each layer, wait about 30 minutes before placing the next layer.
What causes honeycombs in concrete?
Let’s discuss, how it can be done. Lack of compaction, leakage of grout, reinforcement congestion, etc. causes the honeycombs in concrete. Most of the honeycombs are discoverable as they occur close to the surface.
How many stages of honeycomb repair?
Some times honeycomb repair is done in two-stage when depth is higher. There is a maximum thickness that could apply at once. If the construction ground supplier specifies two stages of rectification, shall be followed. Curing shall be done as recommended by the manufacturer.
Can construction groud be mixed?
Construction groud could be mixed as directed by the manufacturer adequately and it could be applied in the area after applying the bonding agent and anticorrosive as per the approved method statement. When the honeycomb is very small, the application of anticorrosive may not be required.
Can you add aggregate to honeycomb?
In general, when the depth of the honeycomb is smaller, no aggregate will be added. However, if the dimension is around 100mm or more, an aggregate could be used. Metal chips could be used as mostly does as the aggregate and generally, the mix proposition will be 1:1.
Can grout be used for honeycomb formwork?
Depending on the shape of the honeycomb formwork arrangement shall be finalized. Construction grout shall be used for the rectification and mix proportions shall be as per the manufacturer’s specification. In general, when the depth of the honeycomb is smaller, no aggregate will be added.
Step 1: Before the Repair
Parging is certainly an option, however it’s a more costly route if you are unable to do it yourself.
Step 2: Cleaning and Preparation
The pad is only a few days old, so I’d like to do this while the concrete is green to help promote adhesion. If you have older concrete where there’s surface damage or spalling, then you’ll need to chisel out or use an angle grinder to remove any loose concrete for a good base for bonding.
Step 3: Mixing the Filler Product
Next is the product I’m using for a filler. There are various products available on the market, this will be based on your location. For me, I’m using Quikrete Anchoring Cement. While it’s primary intent is for anchoring or repairing anchor point, it’s other applications is for repair cracks or surface damage.
Step 4: Applying the Cement Filler
Using the putty knife, apply and force the cement mixture into the honeycombing and pockets. This will ensure it’s filled, when the mixture expands, it’s lock in place.
Step 5: Final Clean Up
A week after, here you can see how the color has changed. Product colors may also vary.
Step 6: All Done!
After a couple of months, we are currently experiencing a milder winter with many freeze and thaw cycles, so you’re able to see how well it’s holding up so far.
What is Honeycomb in Concrete?
Honeycomb in Concrete is the term used to describe hollow spaces and cavities present inside or over the concrete mass. They look like honeybee’s nests as shown in the picture. Honeycombing in concrete usually occurs due to improper vibration and workability of concrete, as mortar does not fill the spaces between the coarse aggregate particles.
How to minimize Honeycomb in Concrete?
Proper concrete placement methods shall be ensured. Concrete shall be placed in layers, with bearable drop height to avoid segregation.
How to repair Honeycomb in Concrete?
Concrete honeycombs which are on the surface are visible to the human eye and can be detected as soon as shuttering is removed. To repair honeycombs that appear on the Surface following methods shall be adopted:
CONCLUSION
We have covered What is Honeycomb in Concrete? | What are the effects and causes of Honeycomb? | How to minimize and repair Honeycomb in concrete? | Frequently asked Questions about Honeycombing in Concrete. Thank you for reading this informative article. Share this article for better reach.
honeycomb repair process in concrete
Use light chipping hammers weighing about 7 kg or less to remove the required amount of concrete, as impact hammers can dissolve the surface of the concrete. Follow up the chipping with sandblasting or water blasting to remove this fractured surface.
Reference
Er. Mukesh Kumar is Editor in Chief and Co-Funder at ProCivilEngineer.com Civil Engineering Website. Mukesh Kumar is a Bachelor in Civil Engineering From MIT. He has work experience in Highway Construction, Bridge Construction, Railway Steel Girder work, Under box culvert construction, Retaining wall construction.
