specs

Section 02200
Page 4
I. Place engineered fill materials in loose lifts of 8 inches and uniformly compact. Use a method so as not to
disturb or damage building drainage systems and waterproofing systems.
J. Engineered fill to be compacted to a minimum relative compation of 90% at 2 or more percent above optimum
moisture content as determined by ASTM D1557 Laboratory Test Procedure.
K. Prior to compaction, each layer to be spread evenly and thoroughly blade mixed during the spreading to obtain
uniformity of material in each layer. Fill to be brought to a water content that will permit proper compaction
by either (a) aerating the material if it is too wet, or (b) spraying the material with water if it is too dry.
Compaction to be performed by footed rollers or other types of approved compaction equipment and methods.
Compaction equipment to be of such deisng that they will be able to compact the fill to specified density.
Rolling of each layer to be continuous over its entire area and the equipment to make sufficient trips to ensure
the required density has been obtained. No ponding or jetting is permitted. When footed rollers are used for
compaction, the density and moisture tests shall be taken in the compacted material below the surface disturded
by the roller.
L. Where temporary unbalanced pressures are liable to develop on walls before floor slabs are placed, erect
necessary shoring to counteract imbalance.
M. At below grade concrete walls, a drainage filter blanket should be placed behind the wall. See geotechnical
report for additional information regarding specifications for drainage filter blanket.
N. Utility trenches extending underneath all traffic areas must be backfilled with native or approved import
material and compacted to relative compaction of 90% to within 6 inches of the subgrade. The upper 6 inches
to be compacted to 95% relative compaction in accordance with Laboratory Test Procedure ASTM D1557.
Backfilling and compaction of utility trenches to meet the requirements set forth by the City of Napa,
Department of Public Works. Utility trenches to be sealed with a compacted impervious cohesive soil material
or lean concrete where the trench enters/exits the building perimeter. Impervious seal to extend a minimum of
2 feet away from the building perimeter.
3.04 GRADING
A. General:
1. Grade under slabs on fill to the elevations shown on the Drawings.
2. Soft and unstable materials which will not readily compact when rolled or tamped shall be removed and
the resulting depression filled with stable material, rolled until firm.
3. Fine grade to the elevations shown on the Drawings.
4. At intermediate points for which finish grades are not indicated, the finish grade shall be of uniform level
or slope between points for which elevations are given.
5. Any abrupt changes in level shall be rounded.
6. Finish points shall slope away from buildings in all directions to assure positive drainage.
7. General grading shall be done with a road or motor grader in such a manner as to result in a generally
smooth surface free of rocks, trash, and other debris required to be removed from the site.
B. Grading outside building lines:
1. Grade areas adjacent to buildings to achieve drainage away from the structures, and to prevent ponding.
2. Finish the surfaces to be free from irregular surface changes and shape the surface of areas under walks to
line grade and cross-section, with finished surface not more than 0.10 ft. above or below the required
subgrade elevation.
C. Grading under building slab:
1. All areas to receive slabs to be wetted to seal any desiccation or shrinkage cracks prior to placing the
underslab components. This work to be done under the observation of the construction Soil Engineer.
2. Grade areas under the building to allow for a 4” layer of ¾” Caltrans Class II aggregate base under the
slabs on grade.
3.05 WATER CONTROL
A. Where subgrade or layer of soil material must be moisture-conditioned before compacting, uniformly apply
water to surface of subgrade or layer of soil material to prevent free water appearing on surface during or
subsequent to compacting operations.
NAPA CENTURY CENTER XD 12
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