AMD 0007 - 35 31 19.pdf

R-562 Flood Rehabilitation Missouri River Nebraska MR00104

SECTION TABLE OF CONTENTS

DIVISION 35 - WATERWAY AND MARINE CONSTRUCTION

SECTION 35 31 19

STONE PROTECTION (RIPRAP, SPALLS, AND BEDDING), AND OTHER AGGREGATES

PART 1 GENERAL

1.1 REFERENCES

1.1.1 DEFINITIONS

1.1.1.1 Stone Protection

1.1.1.2 Riprap

1.2 SUBMITTALS

1.3 GENERAL

1.4 QUALITY ASSURANCE

1.4.1 Stone

1.4.1.1 General

1.4.1.2 Random Sampling

1.5 UNIT PRICE

1.5.1 Measurement for Payment

1.3.2 Basis for Payment

1.6 GENERAL

1.7 WAYBILLS AND DELIVERY TICKETS

1.8 SAMPLING AND TESTING

1.8.1 General Requirements

1.8.2 Evaluation Testing of Stone and Test Results

1.8.3 Initial Sampling and Testing

1.8.3.1 Bulk Specific Gravity

1.8.3.2 Unit Weight and Absorption

1.8.3.3 Soundness in Magnesium Sulfate

1.8.3.4 Soundness in Freezing and Thawing

PART 2 PRODUCTS

2.1 MATERIALS

2.1.1 General Requirements

2.1.2 Riprap

2.1.2.1 Stone Weight Requirements

2.1.3 Spalls

2.1.3.1 Gradation

2.1.4 Bedding Material

2.1.4.1 Gradation

2.1.5 Drainage Structure Filter Material

2.1.5.1 Gradation

2.1.6 Drainage Structure Filter Cover

2.1.6.1 Gradation

PART 3 EXECUTION

3.1 GENERAL

3.2 BASE PREPARATION

3.3 PLACEMENT

3.3.1 Bedding

3.3.2 Spalls

3.3.3 Riprap

3.3.3.1 Above Water Placement

SECTION 35 31 19 Page 1

Am-0007

3.3.3.2 Underwater Placement

3.3.4 CONSTRUCTION TOLERANCES FOR RIPRAP

3.3.5 PROTECTION

3.4 Field Gradation

3.4.1 General

3.4.2 Bedding

3.4.3 Spalls

3.4.4 Riprap

-- End of Section Table of Contents --

SECTION 35 31 19 Page 2

SECTION 35 31 19

STONE PROTECTION (RIPRAP, SPALLS, AND BEDDING), AND OTHER AGGREGATES

PART 1 GENERAL

This section includes material requirements for Riprap, Spalls, Bedding, Toe Trench Drain Previous Fill, Toe Trench Drain Cover, Drainage Structure Filter Material, and Drainage Structure Filter Cover. Note that requirements for Gravel Surfacing are provided in Section 32 15 00.

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.

ASTM INTERNATIONAL (ASTM)

ASTM C136/C136M (2014) Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates

ASTM C88 (2018) Standard Test Method for Soundness of Aggregates by Use of Sodium Sulfate or Magnesium Sulfate

ASTM C127 (2007) Standard Test Method for Density, Relative Density (Specific Gravity), and Absorption of Coarse Aggregate

U.S. ARMY CORPS OF ENGINEERS (USACE)

COE CRD-C 144 (1992) Standard Test Method for Resistance of Rock to Freezing and Thawing

1.1.1 DEFINITIONS

1.1.1.1 Stone Protection

Stone Protection is defined as a system which includes a layer of bedding material or layers of filter material beneath a layer or layers of riprap. Stone Protection is places around structures in slack water or within a dewatered site. Stone Protection may also be used to protect channel banks when it is placed in the dry or in slack water.

1.1.1.2 Riprap

Riprap is normally rock material produced by mechanical methods, with a jaw crusher and grizzly after the stone has been pulled out or hammered out of outcrop, etc. in a quarry. The rock sizes a start from 6" and larger sizes, or similar. Riprap gradations have a maximum top size of 3.5 tons. The rock is meant to protect channel side slopes, outlet and inlet structures, other structures, and levee side slopes and berms from erosion

SECTION 35 31 19 Page 3 from high water velocities and/or impact from ice, tree debris, and other floating debris.

1.2 SUBMITTALS

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

submittals not having a "G" designation are for information only. When used, a designation following the "G" designation identifies the office that will review the submittal for the Government. The following shall be submitted in accordance with Section 01 33 00 SUBMITTAL PROCEDURES:

SD-01 Preconstruction Submittals

Underwater Placement of Stone; G

SD-04 Samples

Stone; G

SD-06 Test Reports

Initial Sampling and Testing; G-DO

Evaluation Testing of Stone; G-DO

Gradation Tests; G-DO

Riprap Material; G-DO

Spalls Material; G-DO

Bedding Material; G-DO

SD-07 Certificates

Riprap; G

Spalls Material; G

Bedding Material; G

Laboratory; G-RO

Quarry Service Records; G-RO

Weigh Scale Certification; G-RO

Certified Weight Scale Tickets; G-RO

SD-10 Operation and Maintenance Data

Space Temperature Control System; G

SD-11 Closeout Submittals

Waybills and Delivery Tickets; G-RO

SECTION 35 31 19 Page 4

1.3 GENERAL

The work specified herein consists of placement of stone protection (bedding, spalls, and riprap), and aggregate filter material such as Toe Trench Drain Previous Fill, Toe Trench Drain Cover, Drainage Structure Filter Material, and Drainage Structure Filter Cover to be used as:

erosion control measures around inlets and outlets of drainage structures, channel bottom ands side slopes, levee side slopes, and berm side slopes;

and seepage control measures along landside portion of drainage structures and at levee landside seepage berm toe, as shown on the drawings and as directed by the Contracting Officer's Representative. Stone protection material shall consist of all stone either Sioux Quartzite, Cold Springs Granite, Granite Mountain (Arkansas) Nepheline Syenite, or another proposed igneous or metamorphic rock to be furnished for riprap material, spalls and bedding. Limestone is considered an inferior rock and shall not be used. The Contractor shall control operations during production of stone protection material so as to ensure that the material delivered and placed will meet all specification requirements. The Contractor shall perform all sampling and testing required for quality control in accordance with Section 01 45 00.00 10, QUALITY CONTROL, and as specified herein.

1.4 QUALITY ASSURANCE

1.4.1 Stone

Submit suitable stone samples and testing prior to delivery of any such material to the worksite.

1.4.1.1 General

All stone shall be durable material as approved by the Contracting Officer. Stone shall be of a suitable quality to ensure permanence in the structure and in the climate in which it is to be used. It shall be free from cracks, blast fractures, seams and other defects that would tend to increase its deterioration from natural causes. A hairline crack that is defined as being detrimental shall have a minimum width of 4 mil and shall be continuous for one-third the dimension of at least two sides of the stone. The stone shall be clean and reasonably free from soil, quarry fines, and shall contain no refuse.

1.4.1.2 Random Sampling

*Am-7

The stone produced by each source will be sampled by the Government for Quality Assurance testing on the basis of once during the production of each 25,000 tons of stone produced each year for the Government. The samples will be evaluated based upon specific gravity, unit weight, bulk specific gravity (SSD), freeze/thaw testing, and absorption.

The Government may perform verification tests as determined necessary for final approval of the stone protection materials from each source. The Contactor will assist in obtaining and transporting samples selected by the Contracting Officer for testing. The samples would be evaluated based upon specific gravity, unit weight, bulk specific gravity (SSD), freeze/thaw testing, soundness, and absorption.

**Am-7

SECTION 35 31 19 Page 5

1.5 UNIT PRICE

1.5.1 Measurement for Payment

Reference section 01 22 00.00 10, MEASUREMENT & PAYMENT.

1.3.2 Basis for Payment

1.6 GENERAL

The work specified herein consists of placement of stone protection as shown on the drawings and as directed by the Contracting Officer's Representative. Where the quantity of removed and stockpiled rock is insufficient to restore armored areas to pre-construction conditions, additional stone (riprap, spalls and bedding) shall be placed as indicated herein. Stone protection material shall consist of all stone to be furnished for riprap, spalls, and bedding material. The Contractor shall control operations during production of stone protection material so as to ensure that the material delivered and placed will meet all specification requirements. The Contractor shall perform all sampling and testing required for quality control in accordance with Section 01 45 00.00 10, USACE QUALITY CONTROL, and as specified herein. The quarry operators shall be responsible for operating all quarries and for conditioning the quarry area after operations are complete, in accordance with all applicable Federal, State, and local laws and regulations.

1.7 WAYBILLS AND DELIVERY TICKETS

Copies of waybills or delivery tickets shall be submitted during the progress of the work. Before the final payment is allowed, waybills and certified delivery tickets shall be furnished for all stone protection materials actually used in the construction.

1.8 SAMPLING AND TESTING

1.8.1 General Requirements

The Contractor shall be responsible for all sampling and testing specified herein. The Government may perform verification tests as determined necessary for final approval of the stone protection material. All samples including samples taken during production shall be representative of the stone protection material furnished or proposed to be furnished. Samples shall be taken in accordance with ASTM D75 or other approved method. All sampling operations shall take place in the presence of a representative of the Contracting Officer's Representative. No rock shall be furnished from any ledge which has not been sampled, tested, and approved for use on this project. *Am-7 Note material property testing does not specifically need to be performed for this project as long as the quarry can provide acceptable testing results from within the previous 12 months, from the same ledge that the material for this project will be obtained.**Am-7

1.8.2 Evaluation Testing of Stone and Test Results

Results shall verify that materials comply with this specification. When

SECTION 35 31 19 Page 6 a material source is changed, the new material will be tested for compliance. When deficiencies are found, the initial analysis shall be repeated and the material already placed shall be retested to determine the extent of unacceptable material. All in-place unacceptable material shall be replaced or modified as directed by the Contracting Officer's Representative.

1.8.3 Initial Sampling and Testing

Tests for bulk specific gravity, soundness in magnesium sulfate, and soundness in freezing and thawing shall be performed on samples of material obtained from each ledge proposed for use as stone protection prior to start of construction. Test results shall describe type of failure of the discrete particles. Certified test results performed not longer than 12 months prior to delivery to the project together with the name of the owner of the quarry and the legal description shall be submitted to the Contracting Officer's Representative. *Am-7 The Contractor shall submit the name and location of each quarry proposed for use along with the geologic section of each quarry indicating the various rock units identified by geologic name of formation and member and indicate from what ledge the samples were obtained.**Am-7

1.8.3.1 Bulk Specific Gravity

Bulk specific gravity shall be computed in accordance with ASTM C 127 except that the total sample shall weigh 5000 grams +2 percent and individual particles shall weigh approximately 300 grams each. Stone protection material shall be tested in a saturated surface-dry (SSD) condition. The computed bulk specific gravity so determined shall not be less than 2.60 g/cc.

1.8.3.2 Unit Weight and Absorption

Stone shall have a bulk specific gravity, saturated surface dry, greater than 2.60 g/cc. The stone shall have an absorption less than 2 percent.

The method of test for unit weight and absorption shall be ASTM C127.

1.8.3.3 Soundness in Magnesium Sulfate

Soundness in magnesium sulfate shall be determined according to ASTM C88 with test modifications as listed below. The combined loss at 5 cycles shall be not more than 8 percent. The test report shall show the percentages of loss calculated as described herein and the number of pieces affected, classified as to number disintegrating, splitting, crumbling, cracking, flaking, etc.

a. Sample Preparation

The sample shall be prepared by breaking it into fragments reasonably uniform in size and shape and weighing approximately 100 grams each. The test sample shall weigh 5000 grams +/- 2 percent. The sample shall be thoroughly washed and dried previous to test as described for coarse aggregate.

b. Sample Immersion and Temperature

SECTION 35 31 19 Page 7

The sample immersed in the solution shall be maintained at a temperature of 80 degrees F +/- 2 degrees F for the immersion period.

c. Quantitative Examination

At the end of the fifth cycle, the percentage loss shall be determined by the three following methods. The test report shall show the loss computed by each method; however, only the combined loss shall be used for acceptance or rejection of the material. Photographs of the samples throughout testing are required.

d. Loss By Breaking

An individual piece which has broken or split into three or more fragments shall be considered to have failed the test, provided each of the three such fragments is at least 10 percent of the original piece by weight. The total original weight of all pieces failing the test, expressed as percentage of the total original weight of the sample, shall be considered as percentage loss by breaking.

e. Loss By Crumbling and Flaking

After the loss by breaking has been determined, the pieces that have not failed in that determination shall be screened on the 1/2-inch sieve and the material retained on the sieve shall be weighed for purposes required to determine combined losses. The pieces which have failed by breaking shall then be added to the material remaining on the 1/2-inch sieve and screened. The difference between the total original weight of the sample and the total weight of the material retained on the 1/2-inch sieve expressed as percentage of the total original weight, shall be considered as percentage loss by crumbling and flaking.

f. Combined Loss

The difference between the total original weight of the sample and the weight of the material retained on the 1/2-inch sieve, after screening the pieces which did not fail by breaking, expressed as percentage of the total original weight, shall be considered as percentage combined loss.

1.8.3.4 Soundness in Freezing and Thawing

The test for freezing and thawing shall consist of COE CRD-C 144 . The test shall be performed on a minimum of three (3) specimens and the loss after twenty (20) cycles shall not exceed two (2) percent. The test report shall shall describe the type of failure of the discrete particles and submitted for approval shall contain information as required by ASTM D5312.

a. Temperature

The temperature of the surrounding medium during freezing shall be in accordance with ASTM D5312.

b. Freeze/Thaw Cycle

The length of a freezing and thawing cycle shall be in accordance with

ASTM D5312.

SECTION 35 31 19 Page 8

PART 2 PRODUCTS

2.1 MATERIALS

2.1.1 General Requirements

All stone for stone protection and other aggregates shall be durable quarried rock as approved by the Contracting Officer's Representative.

Individual pieces of stone protection in-place shall be free from cracks, seams, and other defects that will cause rapid or excessive deterioration or degradation during service. The bulk stone protection material delivered to the project shall be of such quality that tests performed on representative samples have results within the limits specified. The stone protection shall contain not more than 5 percent of undesirable material by weight. Undesirable material is defined as individual pieces of stone which do not meet the quality requirements when tested as specified herein and which can be visually differentiated from the satisfactory pieces, plus dirt, sand, clay, and rock fines. Stone protection material shall not contain disintegrated granite or shale. The Contractor shall select the source or sources they propose to use and perform the initial sampling and testing of the materials well in advance of the time when the material will be required in the work.

2.1.2 Riprap

The riprap shall consist of stone meeting the requirements specified herein and shall be in pieces approximately rectangular in cross section, free from thin slabby pieces having a maximum dimension more than four times the least dimension. Stone for riprap shall be reasonably well graded from coarse to fine. Dirt and fines of less than 1/2-inch maximum cross section, accumulated from interledge layers or from blasting or handling operations shall not exceed 5 percent by weight.

2.1.2.1 Stone Weight Requirements

*Am-7

The riprap shall be reasonably well-graded. Gradation limits are shown below. Stone used for this project is based upon weight requirements given in the Nebraska Department of Transportation (NDOT) Standard Specification for Highway Construction (2017 edition), however, quality standards are as outlined in this specification. The size of riprap is defined by the Type (A, B, or C) as defined in the NDOT Specifications.

The Type of riprap to be used at each site is noted on the contract drawings.

The riprap shall be reasonably well-graded.For gradation tests to perform see paragraph 3.4 Field Gradations.Gradation limits are shown below. The Type of riprap to be used at each site is noted on the contract drawings.

The riprap material shall be continuously graded within the following limits:

**Am-7

SECTION 35 31 19 Page 9

Riprap Type A Gradation Band Percent Lighter Limit of Stone Sieve by Weight Weight (Lbs) Weight (Lbs) Designation

100 120 - 350 175 11-8 50 60 - 175 40 8-6 15 4 - 110 3 4-2

Riprap Type B Gradation Band Percent Lighter Limit of Stone Sieve by Weight Weight (Lbs) Weight (Lbs) Designation

100 245 - 620 350 22-16 50 125 - 265 95 17-13 15 40 - 130 6 13-9

Riprap Type C Gradation Band Percent Lighter Limit of Stone Sieve by Weight Weight (Lbs) Weight (Lbs) Designation

100 580 - 1050 815 40-20 50 115 - 350 175 16-13 15 45 - 175 12 14-9

2.1.3 Spalls

Spalls material shall be at least equal in quality to that of the stone used for riprap and shall be well graded between the sizes specified.

Spalls material shall be quarried stone, crushed cobbles, and crushed gravel consisting of particles having at least one fractured face. The material shall be composed of tough, durable particles, shall be reasonably free from thin, flat and elongated pieces, and shall contain no organic matter nor soft, friable particles in quantities considered objectionable by the Contracting Officer's Representative.

2.1.3.1 Gradation

*Am-7 requirements for gradation specified shall apply to the completed spalls material. The spalls material shall be continuously graded within the following limits:

Requirements for gradation specified shall apply to the completed spalls material. For gradation tests to perform see paragraph 3.4 Field Gradations. The spalls material shall be continuously graded within the following limits:

**Am-7

Sieve Percentage by Weight Designation Passing Square-mesh Sieve

SECTION 35 31 19 Page 10

6 inch 100 4 inch 85-100

2.5 inch 55-100 1 inch 10-50 1/2 inch 0-10 3/8 inch 0-5

2.1.4 Bedding Material

Bedding material shall be at least equal in quality to that of the stone used for riprap and shall be well graded between the sizes specified.

Bedding material shall be quarried stone, crushed cobbles, and crushed gravel consisting of particles having at least one fractured face. The material shall be composed of tough, durable particles, shall be reasonably free from thin, flat and elongated pieces, and shall contain no organic matter nor soft, friable particles in quantities considered objectionable by the Contracting Officer's Representative. The aggregates shall meet the quality requirements of ASTM C33/C33M.

2.1.4.1 Gradation

*Am-7

Requirements for gradation specified shall apply to the completed bedding material. Perform at least one test on each 1000 tons to be placed for each specified gradation in accordance with ASTM C136/C136M. A representative sample weighting not less than 100 pounds shall be removed from the bedding layer placed at locations directed by the Contracting Officer. All points on individual grading curves obtained from representative samples of bedding material shall lie between the boundary limits as defined by smooth curves drawn through the tabulated gradation limits plotted on ENG FORM 2087 or similar form. The individual gradation curves within these limits shall not exhibit abrupt changes in slope denoting either gap grading or scalping of certain sizes or other irregularities which would be detrimental to the proper functioning of the bedding layers. The bedding material shall be continuously graded within the following limits:

Requirements for gradation specified shall apply to the completed bedding material. For gradation tests to perform see paragraph 3.4 Field Gradations. The bedding material shall be continuously graded within the following limits:

**Am-7

Sieve Percentage by Weight Designation Passing Square-mesh Sieve

1-1/2 inch 100 3/4 inch 85-100 3/8 inch 65-100 No. 4 50-85 No. 16 25-55 No. 40 5-35

SECTION 35 31 19 Page 11

No. 100 0-15 No. 200 0-5

2.1.5 Drainage Structure Filter Material

Drainage Structure Filter Material shall be at least equal in quality to that of the stone used for riprap and shall be well graded between the sizes specified. The material shall be composed of tough, durable particles, shall be reasonably free from thin, flat and elongated pieces, and shall contain no organic matter nor soft, friable particles in quantities considered objectionable by the Contracting Officer's Representative.

2.1.5.1 Gradation

A drainage layer shall be constructed around the drainage structure pipes as shown in the drawings. The gradation of the filter material shall be as shown below:

Sieve Size Percent Passing 1” 100 No. 4 97-77 No. 10 70-50 No. 30 40-16 No. 200 3-0

2.1.6 Drainage Structure Filter Cover

Drainage Structure Filter Cover Stone shall be at least equal in quality to that of the stone used for spalls and shall be well graded between the sizes specified. The material shall be composed of tough, durable particles, shall be reasonably free from thin, flat and elongated pieces, and shall contain no organic matter nor soft, friable particles in quantities considered objectionable by the Contracting Officer's Representative.

2.1.6.1 Gradation

The Drainage Structure Filter Cover stone layer shall cover the Drainage Structure Filter Material where the filter material becomes exposed at the landside seepage berm near levee toe, as shown on the drawings. The gradation is the same as specified for spalls, see paragraph 2.1.3.1.

PART 3 EXECUTION

3.1 GENERAL

Quarry operations shall be controlled to produce a reasonably well-graded stone of required size, and the Contracting Officer may require changes as necessary to produce the required product. The Contractor's operations shall be conducted in a manner that will produce stone meeting the requirements specified and shall include selective quarrying, handling, and loading as required. Bedding and spalls composed of the specified materials shall be placed in 9" layers on the prepared subgrade to form a backing and filter for the riprap protection.

SECTION 35 31 19 Page 12

3.2 BASE PREPARATION

Areas on which bedding, spalls, and riprap are to be placed shall be graded and/or dressed to allow placement of the materials. Clear the surface of obstructions, debris, depressions, erosion features (loose eroded soil), vegetation, and any irregularities that would prevent smooth contact with the bedding materials and the surface. Subaqueous area grading shall conform to the cross sections shown on the contract drawings within a allowable tolerance of 2 inches, plus or minus. Above the water, grade within a tolerance of plus 2 inches and minus 4 inches. Where areas are below the allowable minimum tolerance limit, fill with bedding material. No payment will be made for any material thus required.

Immediately prior to placing the bedding layers, the prepared base will be inspected by the Contracting Officer and no material placed thereon until the area has been approved.

3.3 PLACEMENT

3.3.1 Bedding

Bedding material shall be spread uniformly on the prepared subgrade in a satisfactory manner to the slope lines, thickness, and grades indicated on the drawings or as directed. Placing of material by methods which will tend to segregate particle sizes within the bedding will not be permitted. Any damage to the surface of the bedding foundation during placing of the bedding shall be repaired before proceeding with the work.

Compaction of the bedding material will not be required but it shall be finished to present a reasonably even surface free from depressions, mounds, or wind rows.

3.3.2 Spalls

palls shall be spread uniformly on the prepared subgrade in a satisfactory manner to the slope lines, thickness, and grades indicated on the drawings or as directed. Placing of material by methods which will tend to segregate particle sizes within the spalls and bedding will not be permitted. Any damage to the surface of the bedding foundation during placing of the spalls shall be repaired before proceeding with the work.

Compaction of the spalls material will not be required but it shall be finished to present a reasonably even surface free from depressions, mounds, or wind rows

3.3.3 Riprap

3.3.3.1 Above Water Placement

Riprap shall be placed on the bedding and spalls material in the same manner as it was removed or as directed by the Contracting Officer's Representative. Riprap stone shall be placed in such manner as to produce a reasonably well-graded mass of rock with the minimum practicable percentage of voids. Riprap shall be placed to its full course thickness in one operation and in such manner as to avoid damage to the underlying materials and to minimize segregation of riprap. The larger stones shall be well distributed and the entire mass of stones in their final position shall be roughly graded to conform to the gradation specified. The finished riprap shall be free from objectionable pockets of small stones and clusters of larger stones. Placing riprap in layers will not be permitted. The desired distribution of the various sizes of stones

SECTION 35 31 19 Page 13 throughout the mass shall be obtained by selective loading of the material at the quarry or other source. Zero drop height placement procedures are to be utilized for stone to avoid displacing or damaging the underlying spalls and bedding. Riprap shall not be placed by dumping. Dumping of stone at the top of slopes and rolling or pushing into place will not be permitted. Manipulating or moving stone at any time prior to placement by means of dozers or other blade equipment will not be permitted.

Rearranging of individual stones by mechanical equipment or by hand will be required to the extent necessary to obtain a reasonably well graded distribution of stone sizes as specified above. Underwater placement of rock may be required. The rock shall be placed underwater to these placement specifications as much as practicable. The method of underwater placement shall be approved by the Contracting Officer.

3.3.3.2 Underwater Placement

Place riprap and underwater fill in the wet using multiple passes.

Specific methods will depend on water levels at the time of placement.

Maximum drop height for stone placed underwater is three feet. Prior to starting work, submit the proposed method reflecting projected water levels that will minimize segregation.

3.3.4 CONSTRUCTION TOLERANCES FOR RIPRAP

The finished surface and stone (riprap) layer thickness shall not deviate from the lines and grades shown by more than 6 inches. Tolerances are measured perpendicular to the indicated neatlines. Extreme limits of the tolerances given shall not be continuous in any direction for more than five times the nominal stone dimension nor for an area greater than 100 square feet of the structure surface. The Contractor shall verify the tolerance have been met by surveying and provide to COR and Corps for review and approval.

The intention is that the work shall be built generally to the required elevations, slope and grade and that the outer surfaces shall be even and present a neat appearance. Placed material not meeting these limits shall be removed or reworked as directed by the Contracting Officer. Payment will not be made for excess material which the Contracting Officer permits to remain in place.

3.3.5 PROTECTION

The Contractor shall maintain the riprap stone until accepted and any material displaced by any cause shall be replaced at the Contractor's expense to the lines and grades shown on the drawings.

*Am-7

3.4 Field Gradation

3.4.1 General

If the material fails to meet the gradation limits specified, the Contractor shall discontinue placement of the material and adjust his operations, or he shall propose another source. The Contractor shall verify with the necessary additional tests that acceptable materials are being produced. Tests which do not pass the gradation requirements will not be counted in the additional required tests above. All field tests will be performed by the Contractor at his expense. All points on

SECTION 35 31 19 Page 14 individual grading curves obtained from representative samples of materials shall lie between the boundary limits as defined by smooth curves drawn through the tabulated gradation limits plotted on ENG FORM 2087 or similar form. The individual gradation curves within these limits shall not exhibit abrupt changes in slope denoting either gap grading or scalping of certain sizes or other irregularities which would be detrimental to the proper functioning of the material layers.

3.4.2 Bedding

Field gradation tests of bedding materials shall be performed by the Contractor after it has been placed. Samples shall be taken for each 2,500 tons of each layer of material placed in each area from locations directed by the Contracting Officer. Samples shall be tested for gradation according to ASTM C136/C136M. A representative sample weighting not less than 100 pounds shall be removed from the bedding layer for testing.

3.4.3 Spalls

Field gradation tests of spalls materials shall be performed by the Contractor after it has been placed. Samples shall be taken for each 3,000 tons of each layer of material placed in each area from locations directed by the Contracting Officer. Samples shall be tested for gradation according to ASTM C136/C136M. A representative sample weighting not less than 100 pounds shall be removed from the spalls layer for testing.

3.4.4 Riprap

Field gradation tests of riprap material shall be performed by the Contractor on riprap to determine if the material as delivered to the job meets the gradation requirements of this specification. A sample consisting of 4 to 8 tons shall be taken of each material delivered to the job and checked for gradation and elongation. The material from the initial test that meets specifications shall be placed in a well-marked area as designated by the Contracting Officer to serve as a visual model for acceptable material. Material that does not meet specifications shall not be counted as a required test. The Contractor shall state in writing the method used in blasting, processing, loading, and handling this sample, and shall notify the Contracting Officer any time production methods are changed. Riprap material shall not be placed until the material delivered to the job has passed a field gradation testing.

Gradation tests shall be performed according to ASTM D 5519. At the discretion of the Contracting Officer, random loads will be dumped or the in-place material will be sampled and a gradation control check shall be performed by the Contractor at the discretion and under the supervision of the Contracting Officer.

**Am-7

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SECTION 35 31 19 Page 15