Bridges and Structures

Do It Right! Lessons from the field not to be repeated

Backfill

• Structures are to be backfilled with clean sand, not oversize rocks, bricks and construction debris.
• A one-foot maximum lift is allowed when using a vibratory roller . . . but here, only a plate tamper is available, so they will need
  compact and water every 6” lift.

• Backfill with sand, not steel
  plates and bituminous chunks!
  

• The Contractor should fill the bug
  holes before backfilling . . . and make sure to clean the dried concrete off the rebar prior to pouring the end block.

• How will they ever get density
  behind this abutment now?

• More debris in backfill . . .

• Ripples in waterproofing, burying lumber, rebar and concrete rubble in the fill.
• Is there fabric on the conduit? Don’t damage the drainage system while backfilling the wall!

• When backfilling structures, make sure to use only clean sand. Sod, protection fencing and other debris are not allowed.
• Make sure the drainage system is protected from damage when backfilling any structure, but be especially careful when backfilling retaining walls with weep holes.
• This pipe can be sheared off and lead to big problems.

• Before backfilling abutments or retaining walls, make sure that surface cavities are filled and waterproofing has been installed
  correctly.
• Backfill using clean sand, not garbage and concrete.

• Make sure waterproofing stays in
  place during backfilling operations.
• Don’t permit material in backfill
  that might damage waterproofing.

• When backfilling retaining walls with
  daylight drains, make sure the drainage system stays intact.
• All the money spent on all the
  aesthetic treatment in this corridor, only to end up with this mess...