STUDY ON EFFECTS OF NANO-SILICA ON PIPING BEHAVIOUR OF SOIL
Keywords:
Nano-silica, piping behavior, soil stabilization, erosion resistance, hydraulic gradient, hear strength, permeability, geotechnical engineeringAbstract
The piping behavior of soil, which refers to the erosion of soil particles through voids due to seepage forces, is a critical factor in the stability and integrity of geotechnical structures such as dams, embankments, and levees. Piping can lead to catastrophic failure if left unchecked, making the understanding of its mechanisms and methods of mitigation vital for civil engineering. Recent advancements in soil stabilization techniques have led to the exploration of nanomaterials, including nano-silica, as a promising solution for enhancing the soil's resistance to piping. Nano-silica, a nanoparticle form of silicon dioxide, has been recognized for its superior properties, such as high surface area, reactivity, and the ability to improve the mechanical behavior of soils. The study begins with the preparation of soil samples, which are mixed with varying percentages of nano-silica. The soil types used in the experiments include cohesionless (sands) and cohesive soils (clays), as their susceptibility to piping may differ. Nano-silica is added to the soil in amounts ranging from 0.5% to 3% by weight, and the effects of its addition on the soil's physical properties, such as grain size distribution, plasticity index, and compaction characteristics, are first examined. The impact of nano-silica on the soil structure and microstructure is also investigated using scanning electron microscopy (SEM) to visualize changes in particle bonding and pore structure. The primary objective of this research is to evaluate how nano-silica influences the piping behavior of soil under seepage conditions. To simulate real-world conditions, soil specimens are subjected to a constant hydraulic gradient, and the erosion resistance of the treated soil is measured by performing piping tests in a laboratory setting. These tests help to determine the critical hydraulic gradient at which erosion initiates and propagates through the soil, as well as the rate of soil loss during the test.
