Page 7-36
General Pipe Installation Requirements
Concrete Aggregate is used, the Contractor may submit a written request to use a test
point evaluation for compaction acceptance. Test Point evaluation shall be performed
in accordance with SOP 738. Material excavated from the trench shall be used for
backfill above the pipe zone, except that organic material, frozen lumps, wood, rocks, or
pavement chunks larger than 6 inches in maximum dimension shall not be used. Materials
determined by the Engineer to be unsuitable for backfill at the time of excavation shall be
removed and replaced with imported backfill material.
Backfilling of trenches in the vicinity of catch basins, manholes, or other appurtenances
will not be permitted until the cement in the masonry has become thoroughly hardened.
When it is required that a blanket of select material or bank run gravel is to be placed on
top of the native backfill, the backfill shall be placed to the elevations shown in the Plans,
or to the elevations specified by the Engineer. Compaction of the native material shall be
as required by the Contracting Agency and shall be performed prior to placing the select
material. Surface material shall be loosened to whatever depth is required to prevent
bridging of the top layer, but shall in no case be less than 18 inches.
The Contractor shall not operate tractors or other heavy equipment over the top of the
pipe until the backfill has reached a height of 2 feet above the top of the pipe.
7-08.3(4) Plugging Existing Pipe
Where shown in the Plans or where designated by the Engineer, existing pipes shall be
plugged on the inlet end for a distance of 2 diameters with commercial concrete. Care
shall be used in placing the concrete in the pipe to see that the opening of the pipe is
completely filled and thoroughly plugged.
7-08.4 Measurement
Gravel backfill for foundations, or gravel backfill for pipe zone bedding when used
for foundations, shall be measured by the cubic yard, including haul, as specified in
Section 2-09
.
Plugging pipes will be measured per each, for each plug installed, for pipe diameters up
to and including 36 inches. The concrete for plugging pipes in excess of 36 inches in
diameter will be measured by the cubic yard. Computations for corrugated metal pipes
will be based on the nominal diameter.
Excavation of the trench will be measured as Structure excavation Class B or Structure
excavation Class B including haul, by the cubic yard as specified in
Section 2-09
. When
excavation below grade is necessary, excavation will be measured to the limits ordered by
the Engineer.
Embankment construction before pipe placement under the applicable provisions of
Section 7-08.3(1)A
will be measured in accordance with
Section 2-03
.
Shoring or extra excavation class B will be measured as specified in
Section 2-09.4
.