The client constructed Cement plant at Boyireddi palli in Andhra Pradesh. In South India they are the Pioneer’s in cement manufacturing industry In this plant they have 5 cement silo, four bins are for cement storage and one for raw mill
- The Cement bins Silo height is 50Mts and Dia 18 Mts,
- The raw Mill silo Height is 60 Mts and Dia 22 Mts
History:
There could be technical snag with slip form which has resulted in the bad concrete
Current Concern / Issue:
Some portion of the silo walls is damaged which has resulted in the deterioration of concrete. In the monsoons the rain water is seeping into the Silo’s cement compartment, resulting in clogging of cement.Need:
The need was a permanent solution to the leakages through the cracks or possible sources in the Silo Bins.Challenges
The height at which the repair work to carry is the challenge, to carry the repair the client has not provided with suspended platform In consultation with execution team and client consultant, MYK Arment technical cell has derived a solution to halt the seepage into the cement Silo binTechnical Team:
The Technical Manager has closely monitored the progress of the job by visiting the site periodically. During the execution got it executed by the experienced Technical Supervisor in the site. Area: 1000 sq Mts Duration of the project: 40 DaysProducts Recommended:
- Polymer Modified Repair Concrete
- Polymer Modified Repair Mortar
- Flexible Membrane UV Resistant Waterproofing System
- Observed cavities and honey combing between 45 Mts ht down to the 40th Mts Ht. Due to which water is seeping in to the silo bin
- The rain water and moisture travel into the silo due to which the lumps are forming in the Silo bin compartment
- observed unfilled gap between Silo wall and slab
Corrective method:
- Filling up of Cavities
- Filling up of cavities between Silo wall and slab
- Flexible Membrane Waterproof coating to the Entire effected area
Recommendations:
- The weak and loose concrete to be chipped off
- Restrengthening the concrete with polymer modified mortar
- The existing cavities to be refilled with Non Shrink repair concrete
- The honey combed cross section has to be restrengthened it with Micro Concrete mortar
- Flexible membrane Protective coating for concrete resist the penetration of moisture, breathable and forms a vapor barrier
Line of Action:
- Surface preparation
- Application of Bond coat for better adhesion with the concrete surface
- Filling up of cavities and voids of more than 20mm with Non-Shrink polymer modified Repair Mortar
- Capillary filling with polymer modified repair mortar
- Flexible membrane Protective coating to the concrete surface
Surface Preparation:
- The main purpose of the surface preparation is to roughen the surface, creating increased surface area for mechanical bonding.
- Existing loose concrete has been chipped off using chisel and hammer and thoroughly cleaned the surface by mechanical means.
- Ensured there is no contamination such a dirt dust oil form release etc on the substrate.
Application of Bond Coat:
Applied one coat of bond coat ReArm Bond AR 43 in the proportion of 1:1 with cement on to the well prepared Silo wall, voids and cavities with soft paint brush. This will enhance the bonding properties between the dead concrete and the polymer modified repair mortar.
Filling up of Voids of more than 20mm in size:
Apply one coat of bond coat with ReArm Bond AR 43 into the cavities which will enhance the bonding properties with the forthcoming repair concrete. The voids and capillaries in the Silo wall is filled up with Polymer modified Concrete (Non-shrink high strength repair concrete) by admixing ReArm SBR 45 which will enhance the flexural properties and minimizes the shrinkage cracks, and enhances waterproof properties
Voids and capillary filling:
The capillaries in the concrete between 45th Mts to 40th Mts is to be filled with polymer modified Repair mortar.
Apply one coat of bond coat on to the well prepared concrete surface with ReArm Bond AR 43. On wet on wet condition of the bond coat spread repair mortar ReArm Crete RM by admixing ReArm SBR 45 @ 1.5 Lts per bag of 25 Kgs of max 20mm thick with the help of trowel and level the surface. This will fill the voids and capillaries in the effected area of concrete.
Application of Flexible Membrane coating:
Waterproofing System:
AquaArm 2c is ideal application for your terraces, podiums with landscape and shallow water bodies as it is root resistance with excellent crack bridging properties and abrasion resistance. It can be directly applied to your terrace without any protection on top and is UV stable..
AquaArm 2c is the only product in the category which has got a 25 years track record of successful application and performance in the World.
It’s a flexible two component waterproofing coating, which when applied by brush or spray forms a seamless and joint-less crack-bridging waterproofing. When applied at 3.5 kg/ sq Mts to achieve a 1.4 mm dft it will have a crack bridging capacity of 1.5mm it bonds on the wet surface without priming and is vapour permeable. Adhesive strength is approx 1.5 N/mm2 at 28 days.
It is UV resistant and tested up to 7 bars water pressure, and is approved for potable water usage as NF61
The project was completed in all respects successfully. Finally it is tested by spraying water on the effected area with pressure. It is concluded there is no migration of moisture into the Cement Silo Storage compartment.
Conclusion:
Identification of root cause, suitable technical solution and meticulous application by the trained applicator as per the specification and close technical supervision by the technical supervisor has resulted success. The client is very much satisfied.