3.8
Earth materials shall not be placed during weather conditions that do not
allow for proper moisture and density control. CONTRACTOR shall not resume
earthwork operations until the moisture content and the density of the
previously placed soil are as specified. During freezing conditions, subgrades
and each lift of fill must be compacted before the water in the subgrade or the
fill can freeze.
Soil that is too wet for proper compaction shall be removed or disced,
harrowed, rototilled, or otherwise dried to proper moisture content for
compaction to the required density.
Soil that is too dry for proper compaction shall receive water uniformly
applied over the surface of the loose layer. Compaction shall not be performed
until the moisture content of the fill material is uniform. Sufficient water shall
be added to allow for compaction to the required density.
The degree of soil compaction shall be based on a maximum dry density as
determined by the ASTM D698. The minimum degree of compaction required,
unless otherwise noted in plans or directed and approved by ENGINEER, shall
be 95 percent. The moisture content, unless otherwise specified or directed by
ENGINEER, shall be between -2 and +2 percent of the optimum moisture
content determined by ASTM D688.
For Screened Till the degree of soil compaction shall be governed by the in-
place hydraulic conductivity, which shall be no greater than 1 x 10-* cm/sec
when tested in accordance with ASTM D5084.
UTILITY TRENCH BACKFILL
A.
CONTRACTOR shall backfill utility trenches as soon as practicable after the
utility placed and tested in accordance with the appropriate section(s) of the
Specifications and has been observed and approved by the CQA Consultant.
CONTRACTOR is responsible for the satisfactory construction of the utility. If
subsequent testing shows defects in materials or workmanship, then the
necessary repairs and replacements shall be made by CONTRACTOR to the
satisfaction of the CQA Consultant at no additional cost to OWNER.
Trench bedding and backfill shall be as specified on the Drawings. Trench
backfill shall be placed simultaneously on either side of the pipe and
compacted in such a manner as to avoid displacement of the utility.
CONTRACTOR shall place and compact the backfill such that stones do not
strike or remain in contact with the utility.
Trench bedding shall be placed to the spring line of the pipe and shaped so that
the pipe is firmly supported across its diameter for its entire length. Particular
File No. 3066.09 Earthwork 02200 - 10 of 14 December 2017
