Ajaya Kumar Harit
Waterproofing – Retrofitting Inventor/Scientist
India’s construction industry has advanced leaps and bounds over the last 6 decades, however, challenges, as expected to be faced in any developing country, are still far and plenty. Some of the more significant challenges faced within the industry include:
- Sub-optimal performance of the concrete covering the top floor of the RCC structure,
- Rising dampness in walls due to;
– damp proofing course (DPC) failure
– wet sunken slabs,
- Lack of knowledge in terms of choosing the right waterproofing solution.
In this article, I would like to introduce a new technology that combats these challenges. AQUAVENT® is a patented product & a copyrighted technology with respect to:
- The 1st Roof crack (Over deck) management tool.
- The 1st Rising Dampness & DPC failure management tool.
Roofs & Terraces
Sweating of concrete leads to the entrapment of moisture between the RCC slab and the top finishing tiles/PCC in roofs and terraces. This phenomenon is known as the ‘HARITON’ effect. DRY -WET cycles in concrete leads to the development of cracks resulting in the transmission of this moisture to the reinforcement. This leads to the deterioration of the reinforcement, and ultimately the structure.
With walls, the capillary action causes cracks and damages. This capillary action is a cause of DPC Failure. DPC is a damp-proof course barrier laid through the structure to prevent moisture rising by capillary action. Wet soil, when in contact with structural elements (like brick wall, plinth beam, etc.) leads to rising damp, if the DPC barrier fails. This capillary rise in dampness arises through a phenomenon known as the ‘HARIWON’ effect.
With an aim to address these issues, the author took to the field. The following are the findings of the author.
A study was conducted at Dehradun, Uttrakhand since the area typically receives rainfall at least once in a week. Crack development in the sample was observed when there was a sudden downpour on a hot afternoon. The development of a crack on a polymer coated roof in a single day, made it clear that there is some other aspect at play rather than the plain abrupt cooling of the substrate due to sudden temperature change from the sudden rain. To investigate this, a hole was drilled and a pipe and a balloon was fixed over it. The apparatus was fixed to make sure water from rainfall doesn’t go in.
It was observed, the balloon attached at the end of the pipe was seen to inflate a bit next afternoon. We repeated the experiment, and obtained the same result. Through this, we concluded, moist hot air is being released continuously.
To facilitate the hot air release/counter the cracks, initially, we created a chimney sort of arrangement at highest locations-central ridge lines in the roof. This was a cumbersome process and backfired at some locations on account of maintenance issues. A more user- friendly product/ procedure was required.
A product AQUAVENT [R] for roofs, conceived in 1996-97 and AQUAVENT [W/M] for WALLS in 1998 and finally submitted for © COPYRIGHT and PATENT in 2016, when Prof. SK Agarwal, Ex-Head, Structural Civl Engineering, IIT-Roorkee University, suggested it to be shared with the fraternity at large.
About the author:
Ajaya Kumar Harit is a waterproofing -retrofitting inventor/scientist and has to his credit engineered some complicated waterproofing/retrofitting solutions using his signature-without dismantling techniques and solutions. He also has 2 patents and a © COPYWRITE infringement against the products.