This paper presents preliminary findings based on the initial performance evaluation of five approach embankments used in a bridge replacement project over the Salt Fork of the Arkansas River on US Highway 177 in Noble and Kay Counties, Oklahoma. The research involved instrumentation and measurement of four experimental approach embankments and one control approach embankment, all with similar dimensions. Instrumentation inc1uded total pressure cells to measure lateral earth pressure against the abutment wall, inclinometer casings to measure lateral movement of the backfill material and abutment walls, telescoping couplings on the inclinometer casings to measure settlement of the backfill and foundation, amplified liquid settlement gages for measurement of foundation settlement, and piezometers to measure pore water pressure. The four experimental backfills used were geotextile reinforced granular backfill, controlled low strength material backfill, dynamically compacted granular backfill, and flooded and vibrated granular backfill. The control section was unclassified borrow material placed at the contractor\u27s discretion as long as density requirements were met. This paper documents and presents summaries of the preliminary findings regarding initial performance and construction cost of each approach embankment
