DRAINAGE AGGREGATE
PART 1: GENERAL
1.01 Description
Work includes providing and installing all drainage aggregate
materials to the lines and grades designated on the project construction plans.
1.02 Related Work
A. Section - Segmental Retaining Wall Units
B. Section - Geosynthetic Wall Reinf orcement
C. Section - Site Preparation
D. Section - Earthwork
1.03 Reference Standards
A. ASTM D 3034 - Specification for Polyvinyl
Chloride (PVC) Plastic Pipe
B. AASHTO T-27 - Test Method for Gradation Limits Fine Filter Material
C. ASTM D 1248 - Specification for Corrugated Plastic Pipe
D. Where specifications and reference documents conflict, the
Architect/Engineer shall make the final determination of applicable document.
1.04 Certification
A. Contractor shall submit a notarized manufacturer's certification,
prior to start of work, stating that the drainage aggregate meets the requirements of this
specification.
1.05 Delivery, Storage and Handling
A. Plastic Pipe shall be stored in accordance with the
manufacturer's recommendations to prevent damage and deleterious materials from
becoming affixed.
B. Drainage aggregate shall be stored to prevent
contamination with other site and/or fill soils.
1.06 Measurement and Payment
A. Measurement of the drainage aggregate is on a cubic yard
basis.
B. Payment shall cover drainage aggregate supply and installation.
C. Quantity of drainage aggregate as shown on drawings may be increased or decreased
at the direction of the Architect/ Engineer based on construction procedures and actual
site conditions.
D. The accepted quantities of drainage aggregate will be paid for per cubic yard of net
quantities shown on the construction drawings. Waste and overfill are incidental. Payment
will be made under:
Pay Item
Pay Unit
Drainage Aggregate
Cubic Yard
PART 2: MATERIALS
2.01 Definitions
A. Drainage collection pipe shall be a
perforated/slotted PVC or corrugated HDPE pipe. The pipe may be covered with a knitted or
nonwoven geotextile sock specifically designed to function as a filter.
B. Drainage aggregate shall be a free draining material, relative to the
surrounding soil, so as to prevent build up of hydrostatic pressure.
C. Drainage geotextile shall have the following minimum properties or as
recommended by the Design Engineer.
AOS
ASTM D 4751 70-100
Grab Tensile ASTM D 4632
110 lb.
Trap Tear ASTM D
4533 40 lb.
Water Flow ASTM D 4491
75 gpm/f t.
Puncture
ASTM D 4833 40 lb.
2.02 Products
A. Drainage aggregate shall be a clean, 1-inch minus crushed stone
or granular fill meeting the following gradation (sieve size/% passing):
l inch/100-75%, 3/4 inch/50-75%, No.4/0-60%, No.40/0-50%,
No.200/0-5%
B. Drainage pipe shall be manufactured in accordance with ASTM D 3034 and/or ASTM D 1248.
C. Geotextile placed around the drainage aggregate or drain pipe shall be as outlined in
Section 2.01 as recommended by the Design Engineer.
PART 3: EXECUTION
3.01 Drainage Collection Pipe
A. Install the drainage collection pipe according to the line,
grades and sections shown in the project construction plans.
B. Install the drainage collection pipe to maintain gravity flow of water to outside the
reinforced soil zone. Daylight the drainage collection pipe at a storm sewer manhole or
along a slope at an elevation lower than the lowest point of the pipe within the
reinforced soil mass.
C. The main collection drain pipe just behind the segmental units shall be a minimum of 3
inches in diameter. Any secondary collection drain pipe can gravity flow independently or
tie into the main collection drain pipe with laterals at a maximum 50 foot spacing along
the wall face.
3.02 Drainage Aggregate
A. Install the drainage aggregate to the line, grades and sections
shown on the project construction plans.
B. Place the drainage aggregate to a minimum finished thickness and widths shown on the
details herein, or as directed by the Engineer.
C. When a blanket drain is installed, a nonwoven geotextile should be installed prior to
aggregate placement in accordance with the details provided on the drawings.
END OF SECTION
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McNear Brick and Block