Concrete Arch Culvert Behavior—Phase 2

An arch culvert, under a 240-ft. (73-m) embankment, was tested to assess influence on structural behavior of four methods of backfilling, including Method A, employing well-compacted structure backfill; imperfect trenches with various inclusions; and straw surrounding the barrel. At the time of fill completion, stresses due to footing rotations were not great under Method A backfill, but increased appreciably at some stations 2 years after fill completion. Where baled straw surrounded the barrel, severe stresses were indicated due to footing rotations at the time of fill completion—footing rotations and stresses decreased in the 2-yr period following fill completion. In general, good foundation conditions prevented large stresses due to footing differential displacements.