H.08.04_Specification Amended Section 31 00 00 Earthwork 06232021.pdf

CRANEY ISLAND BULKHEAD REFURBISHMENT BULKHEAD

SECTION TABLE OF CONTENTS

DIVISION 31 - EARTHWORK

SECTION 31 00 00

EARTHWORK

08/08

PART 1 GENERAL

1.1 SUMMARY

1.2 PAYMENT

1.3 REFERENCES

1.4 DEFINITIONS

1.4.1 Satisfactory Materials

1.4.2 Unsatisfactory Materials

1.4.3 Cohesionless and Cohesive Materials

1.4.4 Degree of Compaction

1.4.5 Unstable Material

1.5 SUBSURFACE DATA

1.6 SUBMITTALS

PART 2 PRODUCTS

2.1 MATERIALS

2.1.1 BACKFILL

PART 3 EXECUTION

3.1 STRIPPING OF TOPSOIL/SURFACE MATERIALS

3.2 GENERAL EXCAVATION

3.2.1 Drainage

3.2.2 Dewatering

3.2.3 Underground Utilities

3.2.4 Structural Excavation

3.3 SELECTION OF BORROW MATERIAL

3.4 OPENING AND DRAINAGE OF EXCAVATION

3.5 SHORING

3.5.1 General Requirements

3.5.2 Geotechnical Engineer

3.6 STOCKPILES

3.7 FINAL GRADE OF SURFACES TO SUPPORT CONCRETE

3.8 GROUND SURFACE PREPARATION

3.8.1 General Requirements

3.8.2 Frozen Material

3.9 UTILIZATION OF EXCAVATED MATERIALS

3.10 BACKFILLING AND COMPACTION

3.11 SUBGRADE PREPARATION

3.11.1 Proof Rolling

3.11.2 Construction

3.11.3 Compaction

3.11.3.1 Subgrade for Pavements

3.12 SHOULDER CONSTRUCTION

3.13 FINISHING

SECTION 31 00 00 Page 1

3.13.1 Subgrade and Embankments

3.13.2 Capillary Water Barrier

3.13.3 Grading Around Structures

3.14 PLACING TOPSOIL

3.15 TESTING

3.15.1 Fill and Backfill Material Gradation

3.15.2 In-Place Densities

3.15.3 Check Tests on In-Place Densities

3.15.4 Moisture Contents

3.15.5 Optimum Moisture and Laboratory Maximum Density

3.15.6 Tolerance Tests for Subgrades

3.16 DISPOSITION OF SURPLUS MATERIAL

3.17 PROTECTION

-- End of Section Table of Contents --

SECTION 31 00 00 Page 2 e4ecejyc Cross-Out

SECTION 31 00 00

EARTHWORK

08/08

PART 1 GENERAL

1.1 SUMMARY

This specification covers the excavation and backfill requirements of the Bulkhead Refurbishment structure at the Craney Island Dredged Material Management Area (CIDMMA) as shown on the drawings. The existing soils to be excavated are adequate for use as backfill for this project provided the requirements of this specification are followed. If additional soil volumes are requried, they must be obtained from within CIDMMA as directed by the Contracting Officer and meet the minimum requirements of this specification.

1.2 PAYMENT

a. Payment for this work is included in the lump sum payments for Line Item No. 0002 - Demolition of Existing Fender System and Line Item No. 0003 - Construction of New Fender System in the Bid Schedule.

1.3 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

AMERICAN ASSOCIATION OF STATE HIGHWAY AND TRANSPORTATION OFFICIALS

(AASHTO)

AASHTO T 180 (2017) Standard Method of Test for Moisture-Density Relations of Soils Using a 4.54-kg (10-lb) Rammer and a 457-mm (18-in.) Drop

AASHTO T 224 (2010) Standard Method of Test for Correction for Coarse Particles in the Soil Compaction Test

ASTM INTERNATIONAL (ASTM)

ASTM C136/C136M (2019) Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates

ASTM D1140 (2017) Standard Test Methods for Determining the Amount of Material Finer than 75-µm (No. 200) Sieve in Soils by Washing

ASTM D1556/D1556M (2015; E 2016) Standard Test Method for Density and Unit Weight of Soil in Place by Sand-Cone Method

SECTION 31 00 00 Page 3

ASTM D1557 (2012; E 2015) Standard Test Methods for Laboratory Compaction Characteristics of Soil Using Modified Effort (56,000 ft-lbf/ft3) (2700 kN-m/m3)

ASTM D2167 (2015) Density and Unit Weight of Soil in Place by the Rubber Balloon Method

ASTM D2216 (2019) Standard Test Methods for Laboratory Determination of Water (Moisture) Content of Soil and Rock by Mass

ASTM D2487 (2017; E 2020) Standard Practice for Classification of Soils for Engineering Purposes (Unified Soil Classification System)

ASTM D2937 (2017; E 2017; E 2018) Standard Test Method for Density of Soil in Place by the Drive-Cylinder Method

ASTM D422 (1963; R 2007; E 2014; E 2014)

Particle-Size Analysis of Soils

ASTM D4318 (2017; E 2018) Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of Soils

ASTM D6938 (2017a) Standard Test Method for In-Place Density and Water Content of Soil and Soil-Aggregate by Nuclear Methods (Shallow Depth)

1.4 DEFINITIONS

1.4.1 Satisfactory Materials

Any materials classified by ASTM D2487 as GW, GP, GM, GP-GM, GW-GM, GC, GP-GC, GM-GC, SW, SP, SM, SC, CL, ML and is free of debris, roots, wood, scrap material, vegetation, refuse, soft unsound particles, and frozen, deleterious, or objectionable materials.

1.4.2 Unsatisfactory Materials

Materials classified by ASTM D2487 as the above listed Satisfactory Materials without meeting the requirements in Paragraph 2.1 - BACKFILL in Specification Section 31 00 00 , plus CH, MH, OL, OH and Pt are unsatisfactory as fill. Unsatisfactory materials also include those materials containing roots and other organic matter, trash, debris, frozen materials, stones larger than 3 inches in any dimension, and material which cannot support equipment or be properly compacted due to excess moisture.

1.4.3 Cohesionless and Cohesive Materials

Cohesionless materials include materials classified in ASTM D2487 as GW, GP, SW, and SP. Cohesive materials include materials classified as GC, SC, ML, CL, MH, and CH. Materials classified as GM and SM will be identified as cohesionless only when the fines are nonplastic. Perform testing, SECTION 31 00 00 Page 4 required for classifying materials, in accordance with ASTM D4318, ASTM C136/C136M and ASTM D1140.

1.4.4 Degree of Compaction

Degree of compaction required, except as noted in the second sentence, is expressed as a percentage of the maximum density obtained by the test procedure presented in ASTM D1557 abbreviated as a percent of laboratory maximum density. Since ASTM D1557 applies only to soils that have 30 percent or less by weight of their particles retained on the 3/4 inch sieve, express the degree of compaction for material having more than 30 percent by weight of their particles retained on the 3/4 inch sieve as a percentage of the maximum density in accordance with AASHTO T 180 and corrected with AASHTO T 224. To maintain the same percentage of coarse material, use the "remove and replace" procedure as described in NOTE 8 of Paragraph 7.2 in AASHTO T 180.

1.4.5 Unstable Material

Unstable materials are too wet, or too soft, to properly support the structure.

1.5 SUBSURFACE DATA

Subsurface soil boring logs are shown in Appendix A of the Project specifications. This data represents the best subsurface information available; however, variations may exist in the subsurface between boring locations.

1.6 SUBMITTALS

Government approval is required for submittals with a "G" designation;

submittals not having a "G" designation are for Contractor Quality Control approval. Submit the following in accordance with Section 01 33 00

SUBMITTAL PROCEDURES:

SD-01 Preconstruction Submittals

Excavation and Placement Work Plan; G

The Contractor shall submit an excavation and placement plan, meeting all requirements of the US Army Corps EM 385-1-1 and Federal Regulations 29 CFR 1926.652 "Subpart P - Construction Standards for Excavations", 30 days prior to the excavation.

SD-06 Test Reports

Testing

Borrow Site Testing

Copies of all laboratory and field test reports shall be submitted to the Contracting Officer within 72 hours of the completion of the test. Required soils tests, including gradation for fill, backfill, and subgrade materials shall be submitted prior to beginning fill and backfill operations.

SD-07 Certificates

SECTION 31 00 00 Page 5

Testing

Qualifications of the commercial testing laboratory or Contractor's testing facilities.

PART 2 PRODUCTS

2.1 MATERIALS

2.1.1 BACKFILL

BACKFILL shall consist of materials classified as Satisfactory in accordance with Section 1.4.1 "Satisfactory Materials". In addition, the liquid limit of such material must not exceed 50 percent when tested in accordance with ASTM D4318. The plasticity index must not be greater than 8 percent when tested in accordance with ASTM D4318, and not more than 30 percent by weight may be finer than No. 200 sieve when tested in accordance with ASTM D1140. The plastic limit shall not be greater than 12 percent when tested in accordance with ASTM D4318. BACKFILL material shall be non-expansive and free of organic matter, debris, particles larger than 3 inches of size, and other unsuitable material.

BACKFILL material shall be obtained from excavated materials or on-site borrow areas as identified by the COR. If adequate quantities are not available from the excavation, mixing on site materials or the addition of soil chemical treatments is acceptable as long as the final product is within project specifications.

PART 3 EXECUTION

3.1 STRIPPING OF TOPSOIL/SURFACE MATERIALS

If required, and where indicated or directed, strip topsoil to a depth of six inches. Spread topsoil on areas already graded and prepared for topsoil, or transported and deposited in stockpiles convenient to areas that are to receive application of the topsoil later, or at locations indicated or specified. Keep topsoil separate from other excavated materials, brush, litter, objectionable weeds, roots, stones larger than 2 inches in diameter, and other materials that would interfere with planting and maintenance operations. Stockpile any surplus of topsoil from excavations and gradings.

Removal of surface concrete will be required for this project. Use of "rubblized" concrete shall not be used as backfill.

3.2 GENERAL EXCAVATION

Perform excavation of every type of material encountered within the limits of the project to the lines, grades, and elevations indicated and as specified. The contractor shall submit a excavation and placement work plan.

The Plan shall include but not be limited to the Contractor's proposed sequence of construction for the excavation and the placement of required fill material; and methods and types of equipment to be utilized for all construction operations, including sloping, benching or shoring the excavation, transporting, placing and compacting materials. Procedures for accomplishing the control of surface water and dewatering work shall be submitted. The Contractor shall be responsible for the design, installation, maintenance, and performance of all temporary dewatering

SECTION 31 00 00 Page 6 systems. When sheeting, shoring, and/or trench boxes are employed, the dewatering system shall be compatible with the type of shoring to be used.

The Plan shall also include the names and addresses of the commercial testing lab and geotechnical engineer which will perform the soil testing, inspection and construction monitoring and how the required soil testing will be performed.

Perform the grading in accordance with the typical sections shown and the tolerances specified in paragraph FINISHING. Transport satisfactory excavated materials and place in fill within the limits of the work.

Excavate unsatisfactory materials encountered within the limits of the work below grade and replace with satisfactory materials as directed by COR.

Include such excavated material and the satisfactory material ordered as replacement in excavation. Dispose surplus satisfactory excavated material not required for fill in areas approved for surplus material storage or designated waste areas. Dispose unsatisfactory excavated material in designated waste or spoil areas. During construction, perform excavation and fill in a manner and sequence that will provide proper drainage at all times. Excavate material required for fill in excess of that produced by excavation within the grading limits from other approved areas selected by the Contractor as specified.

The contractor is solely responsible for constructing safe, stable, temporary excavations; and should shore, slope, or bench all sides of the excavations as required to maintain stability of both the excavation sides and bottom. Unless the contractor can safely slope back the excavation in accordance with regulations, then the excavation shall be properly sheeted and shored as described in paragraph 3.5 SHORING. Slopes may be adversely affected by the dredging disposal operations, weather, or moisture content.

Satisfactory material shall be properly stockpiled for use later. Unused excavated material shall be properly disposed within the existing Craney Island Disposal Area as shown in the drawings at a location specified by the Contracting Officer.

Prior to the excavation, and to insure the excavation and construction is performed at the correct location, the limits of the excavations and an appropriate offset shall be properly surveyed and staked by a surveyor licensed in the Commonwealth of Virginia. The Contractor shall use at their discretion whatever suitable equipment is necessary to perform the excavation in a safe manner and to obtain a level final grade which minimizes disturbance to the underlying subgrade soils. Satisfactory material shall be placed and compacted as specified in paragraph FILLING AND BACKFILLING. Determination of elevations and measurements of approved overdepth excavation of unsatisfactory material below grades indicated shall be done under the direction of the Contracting Officer.

3.2.1 Drainage

Provide for the collection and disposal of surface and subsurface water encountered during construction. Completely drain construction site during periods of construction to keep soil materials sufficiently dry. Construct storm drainage features (ponds/basins) at the earliest stages of site development, and throughout construction grade the construction area to provide positive surface water runoff away from the construction activity and/or provide temporary ditches, swales, and other drainage features and equipment as required to maintain dry soils. When unsuitable working

SECTION 31 00 00 Page 7 platforms for equipment operation and unsuitable soil support for subsequent construction features develop, remove unsuitable material and provide new soil material as specified herein. It is the responsibility of the Contractor to assess the soil and ground water conditions presented by the plans and specifications and to employ necessary measures to permit construction to proceed.

3.2.2 Dewatering

The contractor should anticipate a considerable amount of ground water present in all excavations due to the nature of the facility. Control groundwater flowing toward or into excavations to prevent sloughing of excavation slopes and walls, boils, uplift and heave in the excavation and to eliminate interference with orderly progress of construction. Do not permit French drains, sumps, ditches or trenches within 3 feet of the foundation of any structure, except with specific written approval, and after specific contractual provisions for restoration of the foundation area have been made. Take control measures by the time the excavation reaches the water level in order to maintain the integrity of the in situ material. While the excavation is open, maintain the water level continuously, at least one foot below the working level. Operate dewatering system continuously until construction work below existing water levels is complete. Submit performance records weekly. Measure and record performance of dewatering system at same time each day by use of observation wells or piezometers installed in conjunction with the dewatering system. Relieve hydrostatic head in previous zones below subgrade elevation in layered soils to prevent uplift.

3.2.3 Underground Utilities

The Contractor is responsible for movement of construction machinery and equipment over pipes and utilities during construction. Perform work adjacent to non-Government utilities as indicated in accordance with procedures outlined by utility company. Excavation made with power-driven equipment is not permitted within two feet of known Government-owned utility or subsurface construction. For work immediately adjacent to or for excavations exposing a utility or other buried obstruction, excavate by hand. Start hand excavation on each side of the indicated obstruction and continue until the obstruction is uncovered or until clearance for the new grade is assured. Support uncovered lines or other existing work affected by the contract excavation until approval for backfill is granted by the Contracting Officer. Report damage to utility lines or subsurface construction immediately to the Contracting Officer.

3.2.4 Structural Excavation

Ensure that subgrades have been inspected and approved by the Contracting Officer prior to concrete placement.

3.3 SELECTION OF BORROW MATERIAL

If required, borrow materials shall be selected to meet requirements and conditions of the particular fill for which it is to be used, and shall be subject to approval. The existing soils to be excavated are expected to be adequate for backfill requirements provided all of the requirements in Section 2.1, "BACKFILL", and Section 1.4.1, "Satisfactory Materials" are met.

Unsatisfactory materials may be mixed and blended by the Contractor such that the resultant mixture meets the classification requirements for a specific backfill material. If adequate quantities are not available on-site, mixing

SECTION 31 00 00 Page 8 on site materials or the addition of soil chemical treatments is acceptable as long as the final product is within project specifications.

Fill material shall be obtained from the on-site borrow sources as directed by the Contracting Officer. The Contractor shall notify the Contracting Officer sufficiently in advance of the opening of any excavation or borrow pit. Except as otherwise permitted, borrow pits shall be excavated to afford adequate drainage. Satisfactory drainage of borrow pits shall be performed by the Contractor as incidental operations to the borrow excavation for on-site borrow material. The Government will provide direction on allowable excavation locations within the designated borrow areas. The borrow materials available within the specified borrow areas are the result of previous dredging operations and consist predominantly of layered mixtures of sand, silt and clay in various proportions overlying marsh deposits. No excavation will be allowed outside of the designated borrow locations unless approved by the Contracting Officer. Rock and/or debris materials are not expected to be encountered in significant concentration. All borrow area side slopes shall not be steeper than 1 vertical on 3 horizontal, regardless of location. Unsatisfactory materials are not to be used in construction.

However, the unsatisfactory materials may be mixed and blended with predominantly sandy or clayey material such that the resultant mixture meets the classification requirements for material as specified in, paragraph

2.1 BACKFILL of this Section. Only suitable, satisfactory materials shall be used for fill in dike and/or ramp embankments.

Borrow areas shall be excavated to the limits and depths as indicated and specified. During excavation of borrow material, the Contractor shall provide temporary ditching, sumping, and pumping or other satisfactory dewatering procedure, so that borrow areas are drained of ground water and surface runoff, and the excavation is accomplished in the dry. Excavation will not be permitted in water nor shall any excavated material be scraped, dragged, or otherwise moved through water. At completion of excavations borrow areas shall be re-graded so that no slopes are steeper than 1V:3H, and abrupt changes in elevation are eliminated.

3.4 OPENING AND DRAINAGE OF EXCAVATION

Notify the Contracting Officer sufficiently in advance of the opening of any excavation or borrow pit to permit elevations and measurements of the undisturbed ground surface to be taken. Except as otherwise permitted, excavation areas providing adequate drainage. Transport overburden and other spoil material to designated spoil areas or otherwise dispose of as directed. Ensure that excavation of any area, or dumping of spoil material results in minimum detrimental effects on natural environmental conditions.

3.5 SHORING

3.5.1 General Requirements

If shoring is required, submit a Shoring and Sheeting plan for approval 15 days prior to starting work. Submit drawings and calculations, certified by a registered professional engineer, describing the methods for shoring and sheeting of excavations. Finish shoring, including sheet piling, and install as necessary to protect workmen, banks, adjacent paving, structures, and utilities. Remove shoring, bracing, and sheeting as excavations are backfilled, in a manner to prevent caving.

SECTION 31 00 00 Page 9

3.5.2 Geotechnical Engineer

Hire a Professional Geotechnical Engineer to provide inspection of excavations and soil/groundwater conditions throughout construction. The Geotechnical Engineer is responsible for performing pre-construction and periodic site visits throughout construction to assess site conditions.

The Geotechnical Engineer is responsible for updating the excavation, sheeting and dewatering plans as construction progresses to reflect changing conditions and submit an updated plan if necessary. Submit a monthly written report, informing the Contractor and Contracting Officer of the status of the plan and an accounting of the Contractor's adherence to the plan addressing any present or potential problems. The Contracting Officer is responsible for arranging meetings with the Geotechnical Engineer at any time throughout the contract duration.

3.6 STOCKPILES

Stockpiles of satisfactory and wasted materials shall be placed and graded as specified. Stockpiles shall be kept in a neat and well drained condition, giving due consideration to drainage at all times. The ground surface at stockpile locations shall be cleared, grubbed, and sealed by rubber-tired equipment, excavated satisfactory and unsatisfactory materials shall be separately stockpiled. Stockpiles of satisfactory materials shall be protected from contamination which may destroy the quality and fitness of the stockpiled material. If the Contractor fails to protect the stockpiles, and any material becomes unsatisfactory, such material shall be removed and replaced with satisfactory material from approved sources at no additional cost to the Government. Locations of stockpiles of satisfactory materials shall be subject to prior approval of the Contracting Officer.

3.7 FINAL GRADE OF SURFACES TO SUPPORT CONCRETE

Do not excavate to final grade until just before concrete is to be placed.

Roughen the level surfaces, and cut the sloped surfaces into rough steps or benches to provide a satisfactory bond.

3.8 GROUND SURFACE PREPARATION

3.8.1 General Requirements

Remove and replace unsatisfactory material with satisfactory materials, as directed by the Contracting Officer, in surfaces to receive fill or in excavated areas. Scarify the surface to a depth of 6 inches before the fill is started. Plow, step, bench, or break up sloped surfaces steeper than 1 vertical to 4 horizontal so that the fill material will bond with the existing material. When subgrades are less than the specified density, break up the ground surface to a minimum depth of 6 inches, pulverizing, and compacting to the specified density. When the subgrade is part fill and part excavation or natural ground, scarify the excavated or natural ground portion to a depth of 12 inches and compact it as specified for the adjacent fill.

3.8.2 Frozen Material

Do not place material on surfaces that are muddy, frozen, or contain frost. Finish compaction by sheepsfoot rollers, pneumatic-tired rollers, steel-wheeled rollers, or other approved equipment well suited to the soil being compacted. Moisten material as necessary to plus or minus TWO

SECTION 31 00 00 Page 10 percent of optimum moisture.

3.9 UTILIZATION OF EXCAVATED MATERIALS

Dispose unsatisfactory materials removing from excavations into designated waste disposal or spoil areas. Use satisfactory material removed from excavations, insofar as practicable, in the construction of fills, bedding (as backfill), and for similar purposes. Submit procedure and location for disposal of unused satisfactory material. . Do not waste any satisfactory excavated material without specific written authorization. Dispose of satisfactory material, authorized to be wasted, in designated areas approved for surplus material storage or designated waste areas as directed. Clear and grub newly designated waste areas on Government-controlled land before disposal of waste material thereon. Do not dispose excavated material to obstruct the flow of any stream, endanger a partly finished structure, impair the efficiency or appearance of any structure, or be detrimental to the completed work in any way.

VDOT #78 or #8 stone must be used in at least 6 inch thick layers behind the wall and below the slab. This material should be obtained from the excavated material, and sufficient quantities retained for use in these areas. As necessary based on availability of #78 and #8 from excavation, other satisfactory materials should be utilized in other areas of backfill.

3.10 BACKFILLING AND COMPACTION

Place backfill adjacent to any and all types of structures, in successive horizontal layers of loose materia not more than 8 inches in depth.

Compact each lift to at least 90 percent laboratory maximum density for cohesive materials or 95 percent laboratory maximum density for cohesionless materials, to prevent wedging action or eccentric loading upon or against the structure. Backfill material must be within the range of -2 to +2 percent of optimum moisture content at the time of compaction.

Prepare ground surface on which backfill is to be placed and provide compaction requirements for backfill materials in conformance with the applicable portions of paragraphs GROUND SURFACE PREPARATION. Finish compaction by sheepsfoot rollers, pneumatic-tired rollers, steel-wheeled rollers, vibratory compactors, or other approved equipment.

3.11 SUBGRADE PREPARATION

3.11.1 Proof Rolling

Contractor's Geotechnical Engineer to provide confirmation of the removal of unsatisfactory material, confirmation of the removal of unstable material, and confirmation of the competency of underlying soils to accept satisfactory materials as fill. Confirmation to be provided by visual observation of the exposed soil subgrade, probing with a steel probe rod, and occasional DCP testing. Proof rolling not required.

Satisfactory materials to be placed as fill on an approved subgrade will need to overlap previously placed fill material by benching into the previously placed material. Fill material is to be placed and compacted per the Project Specification requirements.

3.11.2 Construction

Shape subgrade to line, grade, and cross section, and compact as

SECTION 31 00 00 Page 11 specified. Include plowing, disking, and any moistening or aerating required to obtain specified compaction for this operation. Remove soft or otherwise unsatisfactory material and replace with satisfactory excavated material or other approved material as directed. Bring up low areas resulting from removal of unsatisfactory material or excavation of rock to required grade with satisfactory materials, and shape the entire subgrade to line, grade, and cross section and compact as specified. Do not vary the elevation of the finish subgrade more than 0.05 foot from the established grade and cross section.

3.11.3 Compaction

Finish compaction by sheepsfoot rollers, pneumatic-tired rollers, steel-wheeled rollers, vibratory compactors, or other approved equipment.

Compact to requirements specified in Paragraph 3.10 BACKFILLING AND

COMPACTION.

3.11.3.1 Subgrade for Pavements

Compact to requirements specified in Paragraph 3.10 BACKFILLING AND COMPACTION. When more than one soil classification is present in the subgrade, thoroughly blend, reshape, and compact the top EIGHT inches of subgrade.

3.12 SHOULDER CONSTRUCTION

Construct shoulders of satisfactory excavated material or as otherwise shown or specified. Submit advanced notice on shoulder construction for rigid pavements. Construct shoulders immediately after adjacent paving is complete. In the case of rigid pavements, do not construct shoulders until permission of the Contracting Officer has been obtained. Compact the entire shoulder area to at least the percentage of maximum density as specified in paragraph 3.10 BACKFILLING AND COMPACTION above, for specific ranges of depth below the surface of the shoulder. Finish compaction by sheepsfoot rollers, pneumatic-tired rollers, steel-wheeled rollers, vibratory compactors, or other approved equipment. Finish shoulder construction in proper sequence in such a manner that adjacent ditches will be drained effectively and that no damage of any kind is done to the adjacent completed pavement. Align the completed shoulders true to grade and shaped to drain in conformity with the cross section shown.

3.13 FINISHING

Finish the surface of excavations AND subgrades to a smooth and compact surface in accordance with the lines, grades, and cross sections or elevations shown. Provide the degree of finish for graded areas within 0.1 foot of the grades and elevations indicated except that the degree of finish for subgrades specified in paragraph SUBGRADE PREPARATION. Finish gutters and ditches in a manner that will result in effective drainage.

Finish the surface of areas to be turfed from settlement or washing to a smoothness suitable for the application of turfing materials. Repair graded, topsoiled, or backfilled areas prior to acceptance of the work, and re-established grades to the required elevations and slopes.

3.13.1 Subgrade and Embankments

During construction, keep excavations shaped and drained. Maintain ditches and drains along subgrade to drain effectively at all times. Do not disturb the finished subgrade by traffic or other operation. Protect

SECTION 31 00 00 Page 12 and maintain the finished subgrade in a satisfactory condition until ballast, subbase, base, or pavement is placed. Do not permit the storage or stockpiling of materials on the finished subgrade. Do not lay subbase, base course, ballast, or pavement until the subgrade has been checked and approved, and in no case place subbase, base, surfacing, pavement, or ballast on a muddy, spongy, or frozen subgrade.

3.13.2 Capillary Water Barrier

Place a capillary water barrier under concrete floor and area-way slabs grade directly on the subgrade and compact with a minimum of two passes of a hand-operated plate-type vibratory compactor.

3.13.3 Grading Around Structures

Construct areas within 5 feet outside of structure line true-to-grade, shape to drain, and maintain free of trash and debris until final inspection has been completed and the work has been accepted.

3.14 PLACING TOPSOIL

On areas to receive topsoil, if required, prepare the compacted subgrade soil to a 2 inches depth for bonding of topsoil with subsoil. Spread topsoil evenly to a thickness of FOUR inches and grade to the elevations and slopes shown. Do not spread topsoil when frozen or excessively wet or dry. Obtain material required for topsoil in excess of that produced by excavation within the grading limits from areas indicated.

3.15 TESTING

Perform borrow site testing by a Corps validated commercial testing laboratory or the Contractor's validated testing facility. Submit qualifications of the Corps validated commercial testing laboratory or the Contractor's validated testing facilities. If the Contractor elects to establish testing facilities, do not permit work requiring testing until the Contractor's facilities have been inspected, Corps validated and approved by the Contracting Officer.

a. Determine field in-place density in accordance with ASTM D1556/D1556M, ASTM D2167, or ASTM D6938, as applicable. When ASTM D6938 is used, check the calibration curves and adjust using only the sand cone method as described in ASTM D1556/D1556M. ASTM D6938 results in a wet unit weight of soil in determining the moisture content of the soil when using this method.

b. Check the calibration curves furnished with the moisture gauges along with density calibration checks as described in ASTM D6938; check the calibration of both the density and moisture gauges at the beginning of a job on each different type of material encountered and at intervals as directed by the Contracting Officer. ASTM D2937, use the Drive Cylinder Method only for soft, fine-grained, cohesive soils. When test results indicate, as determined by the Contracting Officer, that compaction is not as specified, remove the material, replace and recompact to meet specification requirements.

c. Perform tests on recompacted areas to determine conformance with specification requirements. Appoint a registered professional civil engineer to certify inspections and test results. These certifications shall state that the tests and observations were performed by or under

SECTION 31 00 00 Page 13 e4ecejyc Cross-Out e4ecejyc Polygon

CAPILLARY WATER BARRIER IS NOT APPLICABLE.

the direct supervision of the engineer and that the results are representative of the materials or conditions being certified by the tests. The following number of tests, if performed at the appropriate time, will be the minimum acceptable for each type operation.

3.15.1 Fill and Backfill Material Gradation

One test per 100 cubic yards stockpiled or in-place source material or when change in material occurs which may affect optimum moisture content or laboratory maximum density. Determine gradation of fill and backfill material in accordance with ASTM D1140 and ASTM D422. Each test shall be performed to classify the soil type in accordance with the Unified Soil Classification System (USCS) ASTM D2487. This will also require each test to be run in accordance with ASTM D4318 and ASTM D2216.

3.15.2 In-Place Densities

a. One test per 1000 square feet, or fraction thereof, of each lift of fill or backfill areas compacted by other than hand-operated machines.

b. One test per 100 square feet, or fraction thereof, of each lift of fill or backfill areas compacted by hand-operated machines.

3.15.3 Check Tests on In-Place Densities

If ASTM D6938 is used, check in-place densities by ASTM D1556/D1556M as follows:

a. One check test per lift for each 3000 square feet, or fraction thereof, of each lift of fill or backfill compacted by other than hand-operated machines.

b. One check test per lift for each 300 square feet, of fill or backfill areas compacted by hand-operated machines.

3.15.4 Moisture Contents

In the stockpile, excavation, or borrow areas, perform a minimum of two tests per day per type of material or source of material being placed during stable weather conditions. During unstable weather, perform tests as dictated by local conditions and approved by the Contracting Officer.

3.15.5 Optimum Moisture and Laboratory Maximum Density

Perform tests for each type material or source of material to determine the optimum moisture and laboratory maximum density values. One representative test per 500 cubic yards of fill and backfill, or when any change in material occurs which may affect the optimum moisture content or laboratory maximum density.

3.15.6 Tolerance Tests for Subgrades

Perform continuous checks on the degree of finish specified in paragraph SUBGRADE PREPARATION during construction of the subgrades.

SECTION 31 00 00 Page 14

3.16 DISPOSITION OF SURPLUS MATERIAL

Remove surplus material or other soil material not required or suitable for filling or backfilling, and brush, refuse, stumps, roots, and timber to a Government disposal area at the direction of the COR.

3.17 PROTECTION

Settlement or washing that occurs in graded, topsoiled, or backfilled areas prior to acceptance of the work, shall be repaired and grades reestablished to the required elevations and slopes.

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