31 23 15.pdf

Tinker AFB, OK TAFB Technical Specifications 2019

April 2019 Page 1 Section 31 23 15

SECTION 31 23 15

EXCAVATION, FILLING AND BACKFILLING FOR BUILDINGS

PART 1 GENERAL

1.1 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to in the text by basic designation only. Unless otherwise noted, the current edition of the reference will be used.

AMERICAN SOCIETY FOR TESTING AND MATERIALS (ASTM)

ASTM D 698 Laboratory Compaction Characteristics of

Soil Using Standard Effort (12,400 ft-lbf/cu. ft. (600 kN-m/cu.m.))

ASTM D 1556 Density and Unit Weight of Soil in Place by the Sand-Cone Method

ASTM D 2487 Classification of Soils for Engineering Purposes (Unified Soil Classification System)

ASTM D 2922 Density of Soil and Soil-Aggregate in

Place by Nuclear Methods (Shallow Depth)

ASTM D 3017 Water Content of Soil and Rock in Place by Nuclear Methods (Shallow Depth)

1.2 SUBMITTALS

Government approval is required for all submittals. The following shall be submitted in accordance with SECTION 01 33 00; SUBMITTAL

PROCEDURES:

SD-09 Reports

Copies of all laboratory and field test reports shall be submitted within two working days of the completion of the test.

1.3 DESCRIPTION OF WORK

This specification covers the furnishing of labor and equipment for excavation, filling and backfilling for structures.

April 2019 Page 2 Section 31 23 15

1.4 DEGREE OF COMPACTION

Degree of compaction shall be expressed as a percentage of the maximum density obtained by the test procedure presented in ASTM D 698

PART 2 PRODUCTS

2.1 MATERIALS

2.1.1 Satisfactory Materials

Satisfactory materials shall comprise any materials classified by ASTM D 2487 as GW, GP, SW, SP, CL, and ML.

2.1.2 Unsatisfactory Materials

Unsatisfactory materials shall comprise any materials classified by ASTM D 2487 as PT, OH, MH, CH, and OL. Unsatisfactory materials also include man-made fills, trash, refuse, or backfills from previous construction. Unsatisfactory material also includes material classified as satisfactory, which contains root and other organic matter, frozen material, and stones larger than three inches. The Contracting Officer shall be notified of any contaminated materials.

2.1.3 Cohesionless and Cohesive Materials

Cohesionless materials include materials classified in ASTM D 2487 as GW, GP, SW, and SP. Cohesive materials include materials classified as ML and CL.

2.2 CAPILLARY WATER BARRIER

Capillary Water Barrier shall consist of clean, crushed, nonporous rock, crushed gravel, or uncrushed gravel. The maximum particle size shall be one and one half inches and no more than two percent by weight shall pass the No. 4 size sieve.

PART 3 EXECUTION

3.1 TOPSOIL

Topsoil shall be stripped, where indicated or directed, to a depth of six inches below existing grade within the designated excavations and grading lines and deposited in storage piles for later use. Excess topsoil shall be disposed as specified for excess excavated material.

April 2019 Page 3 Section 31 23 15

3.2 EXCAVATION

All excavation wi1l be unclassified. Excavate to the dimensions and elevations indicated for each building and structure and include trenching for utility systems to five feet beyond the building line. Extend excavation sufficient distance from walls and footings to allow for placement and removal of forms except where concrete is to be deposited directly against excavated surfaces. If directed, excavate unsatisfactory materials encountered below elevations indicated and replace with satisfactory materials as directed. Place satisfactory excavated materials in required fill or embankment areas. Dispose of surplus excavated materials off base. During construction, provide drainage and pumps as required so that excavation and placement of concrete, fill and backfill shall be in the dry.

Provide required borrow from areas off base selected by the Contractor and subject to approval by the Contracting Officer.

3.3 BLASTING

Blasting will not be permitted.

3.4 UTILITY AND DRAIN TRENCHES

Excavate and backfi11 utility trenches in accordance with applicable parts of SECTION 31 23 16; EXCAVATION, TRENCHING, AND

BACKFILLING FOR UTILITIES SYSTEMS.

3.5 FINAL SURFACES TO SUPPORT CONCRETE

Excavation to final grade shall not be made until just before concrete is to be placed. Do not disturb final grade of excavation.

3.6 FILLING AND SUBGRADE PREPARATION

3.6.1 Preparation of surfaces

Scarify surfaces to a depth of two inches before the fill is started. Plow, step, bench, or break up sloped surfaces steeper than one vertical to four horizontal, so that the fill material will bond with the existing material. When subgrades are less than the specified density, break up the ground to a minimum depth of six inches, pulverize, and compact to the specified density.

3.6.2 Placement

Place material in horizontal layers not exceeding 8 inches in loose depth and six inches in compacted depth, adjust moisture to within plus or minus two percent of optimum, and compact. Do not

April 2019 Page 4 Section 31 23 15 place material on surfaces that are muddy, frozen, or contain frost.

3.6.3 Compaction

Compact each layer to not less than the percentage of maximum density specified below:

Percent Maximum Density

Embankment and Fill Cohesive Material Cohesionless Material (5-15 pi) (0-5 pi) Under structures, building slabs, 95 95 steps, and paved areas Under sidewalks 95 95 Grassed areas 90 90

Subgrade

Under building slabs, steps, and 95 95 paved areas, top six inches Under sidewalks, top six inches 95 95

3.6.4 Reconditioning of Subgrade

Scarify and re-compact approved compacted subgrades that are disturbed by the Contractor's operations or adverse weather prior to further construction.

3.7 CAPILLARY WATER BARRIER

Place the capillary water barrier directly on the subgrade.

Construct the barrier to the thickness shown in layers not exceeding four inches in compacted thickness. Compact each layer with a minimum of two passes of a hand-operated plate-type vibratory compactor.

3.8 BACKFILLING

Do not begin backfilling until construction below finish grade has been completed, underground utilities systems have been inspected and tested, forms removed, and the excavation cleaned of trash and debris. Do not place backfill in wet or frozen areas. Where pipe is coated or wrapped, use backfill material free from stones larger than one inch in any dimension up to an elevation of two feet above utility lines. Do not operate heavy equipment closer to foundation or retaining walls than a distance equal to the height of backfill, but not closer than two feet of the structure; compact the area remaining with power driven hand tampers. Avoid damage to coatings, wrappings, or tanks. Do not place backfill against foundation walls prior to seven days after

April 2019 Page 5 Section 31 23 15 completion of walls. As far as practicable, bring the backfill up evenly on each side of any walls and slope to drain away from wall.

3.9 GRADING

Construct areas five feet outside of each building and structure line true to grade, shape to drain, and maintain free of trash and debris.

3.10 SPREADING TOPSOIL

Areas outside the building lines and areas not to be paved from which topsoil has been removed shall have the topsoil replaced.

Keep the surface free of materials that will hinder planting or maintenance operations. Scarify subgrade to a depth of two inches for bonding. Uniformly spread, grade, and compact topsoil to the thickness, elevations and slopes shown, and leave free of irregularities.

3.11 PROTECTION

Where settlement or washing occurs in top soiled, graded, or backfilled areas prior to acceptance of the work, repair and reestablish grades to the required elevations and slopes.

3.12 TESTING

Compaction testing will be in accordance with ASTM D 1556, ASTM D 2922, ASTM D 3017, or other methods as approved by the Contracting Officer. One test shall be taken for every 2,000 square feet of surface for each lift. Test results shall be furnished to the Contracting Officer within two working days.

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2.2 CAPILLARY WATER BARRIER