Engineering Potential of Pond Ash Geomaterial: A Lightweight Filling Solution

Abstract

This article presents a comprehensive study on the development and characterization of a novel lightweight filling material, pond ash geomaterial (PAGM), composed of pond ash, expanded polystyrene (EPS) beads, cement, and water. The mechanical properties of the PAGM were systematically investigated through a series of laboratory tests, including density, unconfined compressive strength, stress–strain behavior, initial tangent modulus, energy absorption, and a newly introduced density/strength ratio. The effects of various mix ratios, such as EPS/PA (EPS beads to pond ash), C/PA (cement to pond ash), and W/PA (water to pond ash), were studied. The study showed that PAGM density depended on the EPS/PA ratio and ash gradation. Higher cement content (C/PA) enhanced unconfined compressive strength. Increased EPS/PA ratios reduced strength but enhanced ductility. The initial tangent modulus correlated with strength, while energy absorption related to the EPS/PA, C/PA, and W/PA ratios. The density/strength ratio emerged as a novel parameter to tailor PAGM properties, enabling the material to cater to specific engineering needs. The developed PAGM exhibited promising engineering properties and proved to be a strong and sustainable alternative to traditional lightweight construction materials. This study contributes valuable insights for the optimization and utilization of PAGM in various geotechnical applications. Pond ash geomaterial (PAGM) has a wide range of uses in geotechnical engineering, making it an essential solution for a variety of construction projects. The flexibility and on-site customization enable adjusted properties to meet their particular needs. PAGM can be used effectively in controlled backfilling, abutment construction, pipeline trenching, embankment widening, and slope stabilization. Its lightweight design reduces pressure on lateral and subsurface parts, ensuring stability. PAGM offers a sustainable approach to diverse and effective geotechnical solutions by recycling pond ash, an industrial waste product.