This research evaluates the applicability of ponded ash in the production of backfill material. From various ponded ash/sand ratios, cement, and air foam conditions, test specimens were developed to investigate many engineer properties of backfill material. Then, the falling weight deflectometer and excavation tests were carried out to determine the behavior of the material in the actual testbed. The test results suggested that all mixtures achieved optimal flowability performance with acceptable stiffening time. It is indicated that the compressive strength increased as ponded ash and cement contents increased, but the strength decreased with an increase in air-foam content or number of freeze-thaw cycles. From the testbed results, it was found that utilizing 100% ponded ash in the production of backfill material is very promising for sustainable development purpose.

• Tri Ho Minh Le(Ph. D Candidate, Dept. of Civil Engineering, Kunsan National University)
• Dae-Wook Park(Professor, Dept. of Civil Engineering, Kunsan National University)
• Jung-Woo Seo(Graduate Assistant, Dept. of Civil Engineering, Kunsan National University)
• Jun Kim(Graduate Assistant, Dept. of Civil Engineering, Kunsan National University)