Coal ash deposits, often found in by-product sites of coal-fired power stations, can be effectively investigated using Cone Penetration Testing (CPT). This advanced site investigation method assesses and records sediment properties with remarkable accuracy.
The process involves a static hydraulic advancement system slowly pushing a multi-sensor probe into the sediment below. The CPT system collects and records high-resolution data, including crucial site characteristics.
These characteristics include density, shear strength, soil behaviour type, and other derived properties. Engineers then analyze this data to determine the necessary improvements for supporting proposed load-bearing structures.
Continue reading to discover why CPT is an exceptional method for investigating coal ash ponds.
Coal Ash Deposits: How CPT Testing is Helpful
There are various forms that coal ash can take such as solid particles, liquid slurry, or gas. Typically, coal ash is disposed of in expansive ponds that are enclosed by earthen dams, but this can pose a danger if the ash is not uniform or if the dam fails to contain it properly.
As one might expect, coal waste sites are highly regulated by the U.S. Environmental Protection Agency (EPA) and require investigation to evaluate the overall site’s stability and failure risk. By understanding the composition and strength of coal ash and confining structures, geotechnical engineers can make informed decisions and predictions based on collected site data, such as how sediment may behave during an earthquake or severe weather event and what risk mitigation efforts should be implemented to prevent catastrophic damage.
CPT site characterization allows engineers to measure high-resolution sediment characteristics safely and efficiently with minimal disruption to subsurface material. Measuring sediment properties in situ, or “in the original place,” is important as it gives engineers the most accurate assessment of what is deposited at specific depths. Other, more invasive testing methods may disrupt the soil enough that the collected samples do not accurately reflect the in-situ sediment conditions.
Exploring the subsurface conditions of coal ash deposits can be efficiently achieved through CPT. Nevertheless, it is crucial to ensure that the CPT system being used is suitable for coal ash and other waste sites.
Vertek’s S4 CPT Sounding System offers modularity and can be used with a wide track skid steer to provide a low ground pressure footprint and lower capital investment. The benefit of the S4 is that it can be used as needed on a site and be adapted to common construction equipment via quick attach or mounted to a custom self-sufficient trailer.
Vertek’s Track CPT Systems offer the ability to have a powerful track-mounted CPT system that also offers low ground pressure and is built for high levels of CPT production testing. With a lighter and distributed footprint, these track systems are ideal for navigating less stable ground.
As a former CPT provider, Vertek builds systems that provide the reliability and ease of use we want and demand from a system. We can have you up and running with less than a day of training. Contact Team Vertek to discuss your needs and our solutions.