Parametric optimization of bentonite-fly-ash composite core for earthen embankment using Taguchi coupled sunflower optimization algorithm

An earthen embankment needs a centrally stabilized clay core made of locally accessible puddle clay composite with granular soil to retain and redirect storm water. The present work uses waste products such as bentonite and fly-ash to build a low-cost core composite of the earthen embankment. The experimental investigation initiated by characterization of raw soil, bentonite and fly-ash followed by microstructural investigation is carried out by using scanning electron microscopy and energy-dispersive X-ray procter test is employed to stabilize the core composite using different percentage ratios of bentonite and fly-ash according to the Taguchi L9 orthogonal array. To obtain the best possible clay core composite, the design of experiment (DOE) is setup to examine the experimental results for maximum dry density (MDD) and optimum moisture content (OMC) which are found to be 14.3 kN/m³ and 33.43%, respectively. The optimum values of OMC and MDD are decided upon by the experimental results from the Taguchi optimization technique. The analysis of variance has been performed to determine the primary factor influencing the strength of the clay core using signal-to-noise (S/N) ratio. The regression squared value is determined to be 95.96% and 99.76% for MDD and OMC respectively which demonstrates the importance of the DOE. The resulting optimal OMC and MDD are validated using a meta-heuristic technique known as the Sunflower optimization technique. Validated OMC and MDD results are compared with the existing impervious cores around the globe.