TM 5-820-3/AFM 88-5, Chap. 3
(1) Except where individual pipe installation designs are made, cover for pipe beneath roads, streets,
runways, taxiways, aprons, parking lots or similar areas will be provided in accordance with tables B-1
(2) Cover depths are measured from the top of the pavement to the top of the pipe.
(3) Dashes indicate allowable load is less than load on pipe; blanks indicate that pipe is not specified by the
(4) Calculations are based on 120 pounds per cubic foot backfill compacted to 90 percent of CE 55 (MIL-
STD-621) or AASHTO-T99 density (100 percent for cohesionless sands and gravels).
(5) Pipe provided by certain manufacturers exceeds strength requirements established by indicated
standards. When additional strength is proved, the allowable cover limits may be reduced accordingly.
(6) Regardless of minimum cover requirements, the distance from the top of the pipe to the bottom of the
slab for rigid pavements must exceed the values below to prevent cracking of the slab.
(7) Reinforced concrete pipe Classes I through V refer to ASTM size designations (Classes I through V).