19 June 2001
CPM-2: DRY PACK
Description: Packing a stiff mortar into a confined hole or cavity.
Uses: Filling narrow slots cut during repair of dormant cracks, and filling
cavities/small holes in cross-sectional area that are relatively deep.
a. Use for holes no larger than 225 cm2 (35 inches2) in cross-sectional
b. The depth of the cavity should be equal to or greater than the
smallest surface dimension.
c. DO NOT use for:
Shallow depressions where lateral restraint is not obtained.
Filling behind exposed reinforcing steel.
Holes that extend through the structure.
d. Maintain water content of mortar carefully.
a. Thoroughly clean cavity.
b. Remove all loose or cracked aggregate.
c. Allow to dry at least 2 days before packing.
: Vigorously brush inside
of cavity with
a cement slurry:
1 part Type
Portland cement; 1 part clean, dry fine sand; and enough water for a consistency
of thick cream.
Dry Pack Mix: 1 part cement, 2.5 parts sand passing No. 16 sieve, only enough
water so mortar sticks together when squeezed with slight pressure. Take careful
measures to minimize drying shrinkage by selecting a material mix design with a
maximum allowable shortage of 0.05 percent and proper curing.
a. Place and compact in layers 10 mm (2/5 inches) thick.
b. Scratch surface of each layer for good bond of next layer.