What are pond ash embankments?
Pond ash embankment is a human built structure from pond ash. It is a byproduct of coal combustion in thermal power plants. Pond ash embankments can be used for a variety of applications, including:
- Constructing roads and highways
- Raising the level of land
- Creating landfills
- Building dikes and levees
Pond ash embankments are structures made of ash collected from thermal power plants. The leftover part useful for making the embankments are also called pond ash or fly ash.
What is the purpose of pond ash?
Like every other field, the construction world is also putting its full effort into spreading eco sustainability. And pond ash is a big part of it. Instead of using traditional construction material like cement, the construction sector is using pond ash which is not only economical but also eco friendly.
How is pond ash produced?
Pond ash is a perfect mix of fly ash and bottom ash. Fly ash is the fine, powdery particles carried away by the flue gasses from the boiler, while bottom ash is the heavier material that falls into the bottom of the furnace. When fly ash and bottom ash are mixed together with water, they form a slurry (thick suspension) that is then pumped to a disposal pond. Over time, the solids in the slurry settle out, forming a dense deposit of pond ash. The history of pond ash and its embankments is tied to the rise of coal power. As coal plants became more common in the 1800s, massive amounts of ash became a disposal headache. The solution emerged in the early 1900s with pond ash embankments.
Technical properties of pond ash:
- Grain size distribution: Pond ash generally has a coarser grain size compared to fly ash. The grain size varies depending on the source of the coal and the method used for disposing.
- Specific gravity: Pond ash is lighter than most soil but heavier than water as its specific gravity falls between 2.00 and 2.15.
- Moisture content: The moisture content of pond ash varies significantly depending on storage conditions and the weather events when it is stored. It can range from slightly damp to nearly saturated.
- Shear strength: Shear strength refers to the ability of a substance or element to resist deformation under stress. It depends on factors like compaction density, moisture content, and grain size distribution. Generally, well-compacted pond ash exhibits moderate shear strength, making it suitable for some construction applications like embankments (with proper engineering considerations).
Benefits of pond ash embankments:
- Environmentally beneficial: Pond ash embankments conserve natural resources and minimise the risks related to environmental hazards. Not to forget, being a byproduct, pond ash can release pollutants and harm the environment if not managed properly. Hence, stricter regulations are needed to minimise this risk.
- Cost-effectiveness: Pond ash is readily available which means it can be used in embankments at a significantly lower cost than the traditional material . Not only the overall construction cost can be decreased but also concrete strength can be alleviated with pond ash usage.
- Enhanced engineering properties: With proper treatment, pond ash can be stabilized to improve some engineering properties like workability and even shear strength in specific cases. However, improperly compacted pond ash embankments can be less stable than those built with traditional materials.
- Lightweight nature: The lower specific gravity of pond ash compared to conventional soil definitely proves advantageous in many situations. For example, it may prove a 100 times better for building embankments on weak foundations where heavier materials could cause problems.
Implementation of pond ash embankments:
- Site Conditions– Using ground engineering methods to evaluate subsurface oil and ground conditions is a crucial step before implementation of pond ash embankments.. Shear resistance and compressive properties of the foundation soils are the two most important subsurface features impacting embankment construction and performance.
- Material Collection– Necessary materials like sand, clay and other stabilizers can be used together with pond ash to improve the property of embankment. It is worth noting that selection of right material is mandatory for reducing the risk of settlement and ensuring long term stability.
- Embankment Design- Similarly embankment design is something that cannot be ignored. When stability of embankment is analyzed during different circumstances (sudden drawdown, earthquakes, trainloads, waterlogged conditions), it was found that the shorter ones are more prone to safety issues compared to the taller ones.
Including pond ash in embankment construction is not only cost effective but also sustainable. With advanced techniques and continuous quality monitoring, we can surely attain environmentally safe structures. Not to forget, geosynthetic products are something that cannot be ignored if you want to enhance pond ash embankments via reinforcing, separating layers, controlling erosion, and providing environmental benefits in construction practices. This is where our company comes into the picture.
At Strata Global, we turn challenges into opportunities by transforming toxic pond ash, a byproduct of coal combustion, into a valuable resource for sustainable construction. When building NH28, a critical route between India and Nepal, we faced high flood zones and a scarcity of traditional materials. Our innovative use of pond ash enhanced the stability and strength of reinforced soil walls, all while addressing disposal issues and reducing environmental impact. By leveraging the unique properties of pond ash, we prevent shrinkage, swelling, and corrosion, demonstrating our commitment to sustainable development and improved soil structures. Our geosynthetic products like geogrids, geotextiles, geocells, and geocomposites ensure performance boost and durability. If you’re looking for innovative and sustainable solutions for your construction projects, trust Strata Global to provide the expertise and materials you need. Contact us today to learn more about how our geosynthetics and pond ash solutions can transform your next project!