35 43 29.pdf

Emsworth L/D - Back Channel Left Abutment Stabilization and Scour Protection

SECTION TABLE OF CONTENTS

DIVISION 35 - WATERWAY AND MARINE CONSTRUCTION

SECTION 35 43 29

GROUT BAG SCOUR PROTECTION

PART 1 GENERAL

1.1 SUMMARY

1.2 SUBMITTALS

1.3 REFERENCES

1.4 DELIVERY, STORAGE, AND HANDLING

1.5 DESIGN REQUIREMENTS

1.5.1 Grout Mixture Proportions

PART 2 PRODUCTS

2.1 MATERIALS REQUIREMENTS

2.1.1 Grout

2.1.1.1 Portland Cement

2.1.1.2 Fine Aggregate

2.1.1.3 Water

2.1.1.4 Admixtures

2.1.1.5 Mineral Filler

2.1.1.6 Fluidifier

2.1.2 Fabric

2.1.2.1 Grout Bags and Panels

2.1.2.2 Self-Sealing Filling/Venting Ports

2.1.2.3 Mill Widths

2.1.2.4 Seams

2.1.3 Shape Cords, Cables, Zippers and Connecting Hardware

2.1.4 Bedding Material

2.1.5 Geogrid Reinforcement

2.1.6 Dowels or Rebar

2.1.7 Forms

2.1.8 PVC Pipe

PART 3 EXECUTION

3.1 EQUIPMENT

3.1.1 Grouting Equipment

3.1.1.1 Grout Mixer

3.1.1.2 Grout Pump

3.1.1.3 Holding Tank

3.1.1.4 Valves, Gauges, Grout Lines, Headers and Accessories

3.1.2 Panel Jig

3.1.3 Cranes and Floating Plant

3.2 MIX DESIGNS

3.2.1 Field Mix-Design Testing

3.2.2 Other Mix Designs

3.3 CONSTRUCTION AND INSTALLATION REQUIREMENTS

3.3.1 Construction Tolerances

3.3.2 Site Preparation

3.3.3 Geogrid and Empty Grout Bag Placement

3.3.4 Fine Aggregate Concrete Placement

3.3.5 Cast-In-Place Apron Tie-In Element

SECTION 35 43 29 Page 1 W911WN-10-B-0006 Added by Amendment 0002

3.4 COMMUNICATIONS

3.5 CONTRACTOR QUALITY CONTROL

3.6 ENVIRONMENTAL RESTRICTIONS

-- End of Section Table of Contents --

SECTION 35 43 29 Page 2

SECTION 35 43 29

GROUT BAG SCOUR PROTECTION

PART 1 GENERAL

1.1 SUMMARY

This section addresses the requirements for installation of grout filled bags and the cast-in-place apron tie-in element for scour protection downstream of the existing Back Channel Dam apron and adjacent to the sheet pile combination wall, in conformance with these specifications and in accordance with the lines, grades and elevations shown on the drawings.

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

Grout Bag Installation Plan; G|RE

The Contractor shall submit to the Contracting Officer a Grout Bag Installation Plan at least 90 days prior to beginning grout bag installation. The plan shall include the location of specific bags and the location of selected groups of bags, also known as panels. The plan shall be subject to review and comment by the Contracting Officer and shall be modified, if necessary pending results of the Demonstration Project as discussed in Section 35 43 29.15 GROUT BAG DEMONSTRATION PROJECT. The Grout Bag Installation Plan shall include, but not be limited to, the following content:

a. The overall proposed arrangement of grout bags and grout bag panels and sequence of grout bag and grout bag panel placement.

b. Procedures for checking the location of the bags and panels to conform with the lines, grades, contours, and dimensions shown on the drawings.

c. Detailed procedures for placement of grout bags and panels and the sequence of filling of panels with fine aggregate concrete (grout).

d. Details of grout filled bag internal and external reinforcement and tie-in to the existing Back Channel Dam apron and abutment combination wall.

Grout Bag Placement; G|RE

Submit Concrete Grout Bag Placement Plan at least 60 days prior to delivery of grout bags to the job site.

Delivery, Storage, and Handling; G|RE

SECTION 35 43 29 Page 3

Submit delivery, storage, and handling plans for grout bags at least 90 days prior to delivery of grout bag units to the job site.

SD-03 Product Data

Grout; G|RE Fabric; G|RE Shape Cords, Cables, Zippers and Connecting Hardware; G|RE

SD-05 Design Data

Calculations and Design Details; G|RE

Submit calculations and design details attesting to the suitability of each fabric-formed concrete grout bag unit or panel for the purpose contemplated.

SD-06 Test Reports

Cement Grout Mixture Proportions; G|RE

Ninety days prior to installation of grout bags, the Contractor shall submit the mixture proportions that will produce grout of the quality required. Applicable test reports shall be submitted to verify that the grout mixture proportions selected will produce grout of the quality specified.

SD-07 Certificates

Fabric Forms; G|RE

Certificates attesting that the supplied fabric forms meet the criteria of these specifications, as measured in full accordance with the test methods and standards referenced herein.

Certificates shall include the following information about each fabric form delivered:

a. Manufacturer's name and current address.

b. Full product name.

c. Style and product code number.

d. Form number(s).

e. Composition of yarns.

f. Manufacturer's certification statement.

1.3 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 C 117 (2004) Standard Test Method for Materials Finer than 75-um (No. 200) Sieve in Mineral Aggregates by Washing

ASTM C 136 (2006) Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates

SECTION 35 43 29 Page 4

ASTM C 150 (2007) Standard Specification for Portland Cement

ASTM C 31/C 31M (2009) Standard Practice for Making and Curing Concrete Test Specimens in the Field

ASTM C 39/C 39M (2005e1e2) Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens

ASTM C 494/C 494M (2008a) Standard Specification for Chemical Admixtures for Concrete

ASTM C 618 (2008a) Standard Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete

ASTM C 91 (2005) Masonry Cement

ASTM C 937 (2002) Grout Fluidifier for Preplaced-Aggregate Concrete

ASTM D 1784 (2008) Standard Specification for Rigid Poly(Vinyl Chloride) (PVC) Compounds and Chlorinated Poly(Vinyl Chloride) (CPVC) Compounds

ASTM D 1785 (2006) Standard Specification for Poly(Vinyl Chloride) (PVC), Plastic Pipe, Schedules 40, 80, and 120

ASTM D 2256 (2002) Tensile Properties of Yarns by the Single-Strand Method

ASTM D 4354 (1999; R 2009) Sampling of Geosynthetics for Testing

ASTM D 448 (2008) Sizes of Aggregate for Road and Bridge Construction

ASTM D 4491 (1999a; R 2004e1) Water Permeability of Geotextiles by Permittivity

ASTM D 4595 (2009) Tensile Properties of Geotextiles by the Wide-Width Strip Method

ASTM D 4751 (2004) Determining Apparent Opening Size of a Geotextile

ASTM D 4759 (2002; R 2007) Determining the Specification Conformance of Geosynthetics

ASTM D 4873 (2002) Identification, Storage, and Handling of Geosynthetic Rolls and Samples

ASTM D 4884 (1996; R 2003) Strength of Sewn or Thermally Bonded Seams of Geotextiles

SECTION 35 43 29 Page 5

ASTM D 5199 (2001; R 2006) Measuring Nominal Thickness of Geosynthetics

ASTM D 5262 (2007) Evaluating the Unconfined Tension Creep Behavior of Geosynthetics

U.S. GENERAL SERVICES ADMINISTRATION (GSA)

FS RR-W-410 (Rev E) Wire Rope and Strand

1.4 DELIVERY, STORAGE, AND HANDLING

Delivery, storage, and handling of materials shall conform to the requirements specified herein. Plans for the delivery, storage, and handling of grout bags shall be developed and submitted in accordance with paragraph SUBMITTALS.

The grout filled bags or the grout bag panels shall be kept dry and wrapped such that they are protected from the elements during delivery and storage. If stored outdoors, they shall be elevated and protected with a waterproof cover that is opaque to ultraviolet light. The bags shall be labeled as per ASTM D 4873. The bags shall be labeled with the length, width and thickness dimensions of the bag, the bag number, if applicable and the panel number, if applicable.

Upon delivery of grout bags to the site, the grout bag cover or box shall be inspected for damage. Covers that are ripped or boxes that are damaged shall be inspected in detail to determine the extent of damage to the grout bag. If in the opinion of the Contracting Officer, the grout bag is damaged and can not be repaired by sewing, it shall be rejected and removed from the site.

1.5 DESIGN REQUIREMENTS

The physical characteristics of each grout bag and grout bag panel (average thickness, weight per unit area and hydraulic resistance) have been designed to withstand the hydraulic loadings (velocity, depth, duration, shear stress, pressure, and frequency of immersion) for the design discharges present.

The Contractor shall provide to the Contracting Officer documentation in the form of calculations and design details, developed by the grout bag manufacturer and signed by a Registered Professional Engineer licensed in the United States, verifying that each grout bag or grout bag panel meets the physical characteristics presented for the purpose contemplated, in accordance with paragraph SUBMITTALS. Each grout bag or grout bag panel shall be accepted only when accompanied by this documentation.

1.5.1 Grout Mixture Proportions

Grout mixture proportions shall be the responsibility of the Contractor.

Mixture proportions shall include the dry weights of cementitious material(s), the nominal size of the fine aggregate, the specific gravities, absorptions, and saturated surface-dry weights of fine aggregates, the quantities, types, and names of admixtures, and quantity of water per cubic yard of concrete. All materials included in the mixture proportions shall be of the same type and from the same source as will be used on the project.

SECTION 35 43 29 Page 6

The grout mixture shall meet the requirements for the 28-day compressive strength specified in paragraph "Grout" below when tested using grout installed in a sample sock whose fabric matches the material requirements of paragraph "Fabric" below.

PART 2 PRODUCTS

2.1 MATERIALS REQUIREMENTS

2.1.1 Grout

Grout for both the grout bags and the cast-in-place apron tie-in element shall consist of a mixture of Portland cement, fine aggregate (sand) and water so proportioned and mixed as to provide a pumpable fine aggregate concrete. Grout (fine aggregate concrete) mix proportioning shall be the responsibility of the Contractor. The mix for both the grout bags and the cast-in-place apron tie-in element shall exhibit a compressive strength of 7,000 psi at 28 days, when made and tested in accordance with ASTM C 31/C 31M and ASTM C 39/C 39M. Pozzolan, fly ash, fluidifier or pumping aid conforming to this specification may be used at the option of the Contractor at no additional cost to the Government, provided the addition of these additives does not impact the compressive strength requirements stated herein.

2.1.1.1 Portland Cement

Cement used in grout shall conform to the requirements of ASTM C 91, ASTM C 150, Portland cement Type I or Type II. Storage of cement shall be as directed by the Contracting Officer. The Contractor shall employ methods of handling, transporting, and storage that are satisfactory to the Contracting Officer. Only cement furnished in cloth or paper bags will be accepted for use in the work unless bulk cement is approved. A sufficient quantity of cement shall be stored at or near the site of the work to ensure that grouting operations will not be delayed due to shortage of cement. Care shall be taken in storage and handling to protect the cement from contamination and moisture. In the event the cement contains lumps or foreign matter that will not pass through a standard #100 mesh screen, the cement shall be removed from the work site and replaced at no cost to the Government.

2.1.1.2 Fine Aggregate

Sand for grout shall consist of hard, tough, durable, uncoated particles.

It may be composed of natural sand, manufactured sand, or a combination of natural and manufactured sand. The shape of the particles shall be generally rounded or cubical and shall not contain more than 5 percent of flat or elongated pieces having a maximum dimension in excess of five times the minimum dimension. If the sand is a combination of separately processed sizes, classification, or a combination of natural and manufactured sands, the different components shall be batched separately, or, subject to written approval, blended prior to delivery to the mixing plant. The sand shall be well-graded from fine to coarse, and the gradation, as determined in accordance with ASTM C 136 and ASTM C 117, shall conform to the following requirements:

SIEVE DESIGNATION CUMULATIVE PERCENTAGE BY WEIGHT

(U.S. STANDARD SQUARE MESH) PASSING RETAINED

8 100 0 16 95-100 0-5

SECTION 35 43 29 Page 7

30 60-85 15-40 50 20-50 50-80 100 10-30 70-90 200 0-5 95-100

In addition to the grading limits shown, all sand used in the work shall have a fineness modulus within the range of 1.50 to 2.00. The grading of the sand as delivered to the mixes, during any 24 hour period of operation, shall be controlled so that the fineness modulus of samples taken will not vary more than 0.10 from the average fineness modulus. The results of previous tests and the service record may be used to determine the acceptability of the sand. Sand shall be stored in a manner to facilitate drainage and avoid the inclusion of any foreign materials in the grout.

2.1.1.3 Water

Water for mixing shall be clean and free from injurious amounts of oil, acid, salt, alkali, organic matter or other deleterious substances. The Contractor shall conduct applicable water testing and certification that the water is suitable for use in the grout. The tail water must be filtered to remove debris prior to use in grout. Water for the grout shall come from the same source used in the field test mixes.

2.1.1.4 Admixtures

An admixture is any material other than water, sand, and cement added to the grout immediately before or during its mixing to alter its chemical or physical properties to a desired characteristic during its fluid or plastic state. Admixtures shall conform to ASTM C 494/C 494M at the time of acceptance testing sample submittal, and the Contractor shall furnish certification from the manufacturer that the material meets all the requirements of these specifications. All admixtures to be used in each batch of grout shall be separately packaged and weighed prior to use.

Accelerator additive shall be calcium chloride (CaCl2) in amounts up to 2 percent (2%) of the cement by weight or an approved product manufactured for the specific purpose of accelerating grout setup time. The calcium chloride shall be granular or flaked and added to the grout by dissolving it in a portion of the mix water.

2.1.1.5 Mineral Filler

Fillers used in grout as replacement for a portion of the cement shall be fly ash composed of finely divided siliceous residue and in accordance with ASTM C 618, Class F. If the Contractor proposes to use fly ash in the grout mix, it shall conform to the requirements of Section 03 31 01.00 10 CONCRETE AND OTHER CONCRETE SECTIONS. The source, type and quality of the fly ash requires the Contracting Officer's approval before incorporation into the grout mix. The maximum amount of fly ash should not exceed 30 percent (30%) of the cement by weight.

2.1.1.6 Fluidifier

Fluidifier shall be a compound possessing characteristics which will increase the flowability of the mixture, assist in dispersal of the cement grains, and neutralize the setting shrinkage of the grout. The quality of the material shall meet the requirements specified in ASTM C 937. Sampling of fluidifier shall be done by an authorized representative of the Contracting Officer. Trial mixtures should be tested prior to using the materials in field work. All tests will be made by and at the expense of

SECTION 35 43 29 Page 8 the Government.

2.1.2 Fabric

The fabric used in the manufacturing of grout bags or grout panels shall be composed of synthetic yarns formed into a woven fabric. Yarns used in the manufacture of the fabric shall be high strength multifilament polyester.

The fabric shall be woven with a minimum of 50 percent textured yarns (by weight) to improve adhesion to fine aggregate concrete and to improve filtration. Partially-oriented (POY), draw-textured, and/or staple yarns shall not be used in the manufacture of the fabric. Each layer of fabric shall conform to the physical, mechanical and hydraulic requirements referenced herein. The fabric shall be free of defects or flaws which significantly affect their physical, mechanical, or hydraulic properties.

The following Minimum Average Roll Values (MARV) shall be met.

Property Requirements - Grout Bag Fabrics 1, 2

Property Test Method Units Values

Wide Width Tensile Strength-Mach ASTM D 4595 lbf./in. 650 Wide Width Tensile Strength-Cross ASTM D 4595 lbf./in. 650 Elongation at Break-Machine ASTM D 4595 % 15 Elongation at Break-Cross ASTM D 4595 % 15 Mass Per Unit Area ASTM D 5262 oz./sy 10 Thickness ASTM D 5199 mils 25 Apparent Opening Size ASTM D 4751 US Std. Sieve 200

Permittivity or Flow Rate ASTM D 4491 gal/min/ft2 1.85

Notes:

1. Conformance of filter fabrics to specification property requirements shall be based on ASTM D 4759.

2. To meet MARV, the average of test results from any sample roll in a lot shall meet or exceed the minimum values. Lots shall be sampled according to

ASTM D 4354.

2.1.2.1 Grout Bags and Panels

Grout bags shall consist of two or more layers of woven fabric sewn together to form a six sided bag with a cross-section shown in the drawings. The upper and lower sides of the form shall be joined together by spaced straps of uniform length to form a concrete armor unit with an average thickness of 3.0 feet and a nominal mass per unit area of 420 pounds per cubic foot. The straps shall be attached to cords interwoven into the upper and lower sides of the armor unit forms and shall have a minimum breaking strength of 1000 pound-feet. when tested in accordance with ASTM D 2256. After the armor unit form has been filled with fine aggregate concrete the straps shall be on approximately 8.0 inch by 8.0 inch center spacing. The straps shall connect the upper and lower sides of the armor unit form to form a comparatively uniform surface appearance.

When filled with fine aggregate concrete the armor unit form shall form a concrete armor unit with finished average unit dimensions of either 18.0 feet by 6.0 feet by 3.0 feet in thickness and a nominal unit volume of

12.0 cubic yards, 12.0 feet by 6.0 feet by 3.0 feet in thickness and a nominal unit volume of 8.0 cubic yards, or 25.0 feet by 6.0 feet by 3.0 feet in thickness and a nominal unit volume of 16.7 cubic yards, as shown on the drawings. Grout bag panels shall consist of several grout bags arranged

SECTION 35 43 29 Page 9 in an orientation shown on the drawings to cover a select area.

2.1.2.2 Self-Sealing Filling/Venting Ports

Each individual grout bag shall be equipped with at least two (2) self-sealing filling ports; one venting port suitable for the outflow of water during the concrete filling and one filling port suitable for use with an injection pipe at the end of a pump hose for fine aggregate concrete filling. Each filling port shall be constructed with two flanges;

one epoxied to each side of the upper layer of fabric. The exposed fabric at the center of the port shall be cross slit to allow the insertion of a concrete filling pipe. Each filling port flange shall be polypropylene with a 4.0 inch inside diameter and a 10.0 inch outside diameter and a minimum thickness of 0.25 inches. The ports shall be installed at predetermined locations; these locations shall correspond to the higher elevation (upstream) end of the grout bag when installed on the proposed 3H:1V slope.

2.1.2.3 Mill Widths

Mill widths of fabric shall be a minimum of 76 inches, to accommodate the 72-inch minimum design width of the grout bags. Each selvage edge of the top and bottom layers of fabric shall be reinforced for a width of not less than 1.5 inches by adding a minimum of 10 warp yarns to each selvage construction. Mill width rolls shall be cut to the length required, and the two layers of fabric separately joined, bottom layer to bottom layer and top layer to top layer, by means of sewing thread, to form multiple mill width panels.

2.1.2.4 Seams

All seams sewn in the factory shall not be less than 400 pound-feet per inch. when tested in accordance with ASTM D 4884. All sewn seams and zipper attachments shall be made using a double line of U.S. Federal Standard Type 401 stitch. All stitches shall be sewn simultaneously and be parallel to each other, spaced between 0.25 inches to 0.75 inches apart.

Each row of stitching shall consist of 4 to 7 stitches per inch. Thread used for seaming shall be polyester.

2.1.3 Shape Cords, Cables, Zippers and Connecting Hardware

Shape cords shall consist of strips of fabric meeting the material requirements of paragraph "Fabric". The straps shall be positioned at the locations shown on the drawings to maintain the thickness of the grout bag at the designed distance, with a tolerance in thickness not to exceed one and one-half inches. The connection of the straps to the fabric shall be secure and provide a strength capable of sustaining the pressure created by the grout in the bag.

Cables for connecting individual grout bags into the panels and connecting individual grout bags shall be 7 x 19 galvanized steel cables located as shown on the drawings. The cables shall meet the requirements of FS RR-W-410. The tensile strength of the cables shall be at least 12,000 pounds. Steel grommets shall be provided in the sidewalls of the grout bags to allow the cables to connect adjacent bags. Any openings (steel grommets or filling ports) or seams in the fabric shall be located a minimum of one (1) foot from hypocycloid openings on both the side wall and the end walls of the grout bags.

SECTION 35 43 29 Page 10

Zippers shall be brass toothed and connected to the fabric form bag as shown on the drawings.

Connecting hardware for attaching cables of adjacent panels shall be galvanized swages, cable fittings or other galvanized connecting devices that provide a minimum of 80% of the rated breaking strength of the cable.

Cable overlap shall be a minimum of six (6) inches.

2.1.4 Bedding Material

The bedding material beneath the grout filled bags shall be a cohesionless, hard, durable, free draining angular material. The bedding material stone shall be size number 1 stone, in accordance with ASTM D 448, with the following gradation:

Sieve Designation Percentage Passing by Weight 4 inch 100% 3 inch 90%-100% 2-1/2 inch 25%-60% 1-1/2 inch 0%-15% 3/4 inch 0%-5%

The quality of the material shall be subject to the approval of the Contracting Officer, including the source of the material. The Contractor shall provide documentation from an approved geotechnical laboratory that the material meets the subject requirements.

2.1.5 Geogrid Reinforcement

The geogrid soil reinforcement to be used shall meet the requirements of Section 31 05 19.19 GEOGRID REINFORCEMENT.

2.1.6 Dowels or Rebar

Dowels or rebar used in the cast-in-place apron tie-in element shall meet the requirements of paragraph "Steel Reinforcing Bars And Dowels" of Section 03 20 02 STEEL BARS, WELDED WIRE FABRIC, AND ACCESSORIES FOR

CONCRETE REINFORCEMENT.

2.1.7 Forms

Forms for constructing the cast-in-place apron tie-in element at the dam apron (including the leveling plate) shall meet the requirements of Section

03 11 14.00 10 FORMWORK FOR CONCRETE.

2.1.8 PVC Pipe

PVC pipe shall be manufactured from a Type I, Grade 1, polyvinyl chloride (PVC) compound with a cell classification of R454 per ASTM D 1784. The pipe shall be manufactured in strict compliance to ASTM D 1785.

SECTION 35 43 29 Page 11

PART 3 EXECUTION

3.1 EQUIPMENT

3.1.1 Grouting Equipment

3.1.1.1 Grout Mixer

The grout mixer shall be a high-speed, high-shear, colloidal type grout mixer capable of continuous mechanical mixing that will produce uniform and thoroughly mixed grout which is free of lumps and undispersed cement. The mixer shall be equipped with a suitable water and admixture measuring devices calibrated to read in cubic feet to the nearest tenth and so designed that after each delivery the hands can be conveniently set back to zero. The water meter shall have a certificate of calibration from an independent laboratory. Prior to each use, the water meter shall be checked for accuracy and, if necessary, recalibrated.

3.1.1.2 Grout Pump

The grout pump shall be of the positive displacement type, and shall be capable of pumping at all flow rates below 20 gallons per minute (gpm), and shall be capable of pumping at the pressure of at least 50 psi at zero flow rate. The pumping equipment to be used shall be capable of providing the necessary head to meet the maximum distance and elevation between the grout delivery truck and the location of grout bags to be filled, while also accommodating the physical flow characteristics of the grout and its additives. The pumping equipment shall possess variable stroke and speed controls.

For neat cement grout, the pump shall have a screen with 0.125 inch maximum clearance to sieve the grout before being introduced into the pump.

Screens are not required for shear type mixers. A pump shall also be available which is capable of pumping both neat cement grout mixes and sanded grout mixes. The pumping equipment shall have a pressure gage capable of measuring pressures of at least 150 psi or twice the required grout pressure, whichever is greater.

3.1.1.3 Holding Tank

Holding tank(s) or sump(s) shall be of the mechanically agitated type and provide a high volume and continuous injection of grout. The sump shall be capable of holding the solids of the mix in suspension and have a capacity of at least 12 cubic feet of grout or three times the capacity of the mixing system. Volume of grout used from the agitator holding tank(s) or sump(s) shall be measured by a vertical graduated stick or marks at different levels in the tank(s)/sump(s).

3.1.1.4 Valves, Gauges, Grout Lines, Headers and Accessories

Valves, pressure gauges, grout lines, header arrangements, and accessories shall provide a continuous supply of grout and accurate pressure control.

Grout shall be conveyed between the pump and the hole using a single-line system consisting of a pipe or hose or combination of both extending from the pump discharge to the header at the hole collar with grout injection rate controlled by the pump speed or circulating double-line system composed of a supply line to the header at the hole collar and a return line from the header to the grout pump, sump, or holding tank. Grout lines shall consist of either black steel pipe or reinforced rubber or plastic

SECTION 35 43 29 Page 12 hose or a combination of both. The maximum inside diameter of all grout lines shall be 2 inch. The grout injection rate for the single-line system shall be controlled by the pump speed so that settlement of solids within the lines will not occur when pumping at or above the minimum discharge capacity of the pump. The pressure in the double-line system shall be controlled by one or more valves on the control line. The distance between the hole and the pump or holding tanks shall be as short as possible to minimize the accumulation of solids and possible clogging. Pressure gauges shall be high precision, graduated with divisions not greater than 2 psi on the dial face, calibrated and certified correct prior to use. Gauges shall be tested for accuracy as directed by the Contracting Officer during the work by cross comparison with a standard set of oil-filled gauges. The moving parts of all gauges shall be protected from dust, grit, and direct contact with grout.

3.1.2 Panel Jig

The jig for setting grout bag panels shall be constructed by the Contractor and be capable of handling the forces expected to be encountered during typical operations. The jig shall be of a size that can accommodate the panel size recommended by the grout bag manufacturer and approved by the Contractor and shall contain framing to allow connection and subsequent movement of the jig using a crane located on a floating plant. The jig may be outfitted with global positioning system hardware for use in establishing location of panels. Placement of the panel jig shall be carefully performed by the Contractor as to prevent damage to the geogrid reinforcement and any damaged geogrid reinforcement shall be removed and replaced at the expense of the Contractor.

3.1.3 Cranes and Floating Plant

The cranes and floating plant to be used in grout bag installation shall meet the requirements of Section 01 11 00 GENERAL REQUIREMENTS.

3.2 MIX DESIGNS

3.2.1 Field Mix-Design Testing

The Contractor shall conduct field mix-design testing for all proposed grout mixes. These tests shall be conducted onsite, under conditions similar to actual grouting conditions. For each grout mix, the following characteristics shall be determined:

a. Specific Gravity

b. Viscosity

c. Percent Bleeding

d. Pressure Filtration Coefficient

e. Initial Set Time

f. Final Set Time

g. Compressive Strength (at 3-. 7-, 14-, and 28-day intervals)

The Contractor shall be required to make compressive strength test specimens, a minimum of once per shift per mix, noting that the specimens are representative of the amount of cementitious mix placed during the shift. Additional specimens may be made at the option of the Contractor to minimize the amount of cementitious mix represented by each set of compressive strength specimens.

SECTION 35 43 29 Page 13

3.2.2 Other Mix Designs

Other mix designs may be developed after the start of the grouting program, if field mix-design test results or other site conditions indicate it to be necessary. All such grout mixes shall be tested to determine the characteristics listed above.

3.3 CONSTRUCTION AND INSTALLATION REQUIREMENTS

3.3.1 Construction Tolerances

The Contractor shall comply with the following tolerances in constructing the grout bag scour protection:

Feature, Dimension, Design Allowable Variation or Property Value Minimum Maximum

Subgrade elevation Per Drawings -6 inch 0 inch Bedding Thickness 18 inches -6 inch NA Grout Bag elevation Per Drawings -6 inch 0 inch Grout Bag thickness 36 inches 34.5 inch NA Grout Bag to Grout 0 inches 0 inch 1 inch Bag Separation Adjacent Grout Bags 0 inches +3 inch -3 inch (Transverse to flow) Adjacent Grout Bags 0 inches 0 inch +3 inch (Parallel to flow) (Upstream above Downstream) Grout Bag to Existing 0 inches 0 inch +4 inch Feature Separation Hypocycloid Openings 0.5 SF -10% +20% Grout Bag Unit Wt. 135 pcf 130 pcf NA Grout Bag Volume Per Drawings -5% NA (Standard Grout Bag)

The Contractor shall confirm these tolerances for each individual grout bag installed on the project. Measurements on adjacent grout bags shall be obtained along the perimeter in several locations along each side of the grout bag. The Contractor shall conduct all measurements, soundings, diving inspections, and tests of grout bag unit weight and volume necessary to show compliance with the required tolerances.

The Contractor shall proceed with the dredging, bedding material, geogrid and grout bag placement in a timely manner, to avoid changes in the proposed grades constructed or movement of the materials by riverflow or other displacement. The Contractor shall take the necessary steps to minimize these changes, so that grout bag construction can meet the necessary hydraulic requirements and construction tolerances specified.

3.3.2 Site Preparation

Areas on which grout bags or grout bag panels are to be placed shall be constructed to the lines, grades, contours, and dimensions shown on the drawings and to the tolerances listed in paragraph "Construction Tolerances". All obstructions, such as roots, debris and projecting stones, shall be removed except if removal of these obstructions endangers the stability of an adjacent structure. The Contractor shall notify the Contracting Officer if he encounters a situation where this may occur. The Contracting Officer may reduce the proposed bedding thickness requirement

SECTION 35 43 29 Page 14 if he determines that the obstruction will not impact the installation of the grout bags. If removal of such obstructions results in areas that are below design grades, they shall be brought to grade by placing compacted layers of select material meeting the requirement of paragraph "Bedding Material" of this specification section. The thickness of layers and the amount of compaction shall be as specified by the Contracting Officer.

Where required by the specifications, soft and otherwise unsuitable subgrade soils shall be identified, excavated, and replaced with select materials in accordance with the specifications.

Immediately prior to placing the grout bag or grout bag panels, the prepared area shall be inspected by the Contracting Officer, and no grout bags shall be placed thereon until the area has been approved.

3.3.3 Geogrid and Empty Grout Bag Placement

Upon approval of the graded surface by the Contracting Officer, the geogrid shall be installed. Installation shall be performed in accordance with paragraph "Installation" of Section 31 05 19.19 GEOGRID REINFORCEMENT. If necessary, the geogrid shall be secured to the bedding material, to avoid flotation or movement during empty grout bag placement. The geogrid shall be inspected to verify that adjacent pieces abut. The method to secure the geogrid shall be recommended by the Contractor and approved by the Contracting Officer

Following placement of the geogrid and acceptance by the Contracting Officer, grout bags or grout bag panels shall be placed directly on the prepared subgrade to the limits shown on the drawings. The Contractor shall install grout bags in stages as shown on drawings, with the filling ports located at the higher elevation (upstream) end of the grout bag. The Contractor shall progress the grout bag installation from left to right (looking downstream) and from downstream end of the grout bag scour protection towards the existing dam apron. The procedure for setting the bags or panels shall be as documented in the Grout Bag Installation Plan, as discussed in paragraph "Submittals" of this specification section. The jig for setting grout bag panels shall be positioned over the proposed location using a crane suitable for this application.

Immediately prior to filling with fine aggregate concrete, the assembled grout bags or grout bag panel shall be inspected by the Contracting Officer, and no fine aggregate concrete shall be pumped therein until the placement and location have been approved. At no time shall the grout bags be exposed to ultraviolet light (including direct sunlight) for a period exceeding five days.

3.3.4 Fine Aggregate Concrete Placement

Following the placement of the fabric form, the filling pipe at the end of the fine aggregate concrete pump hose shall be inserted through one of the self-sealing filling valves/ports at the higher elevation (upstream) end of the bag. Fine aggregate concrete shall be pumped between the top and bottom layers of fabric, filling the forms to the recommended thickness and configuration. The Grout Bag Installation Plan shall be referenced and followed for this component of work. Pumping shall proceed from the low elevation point in the grout bag to the high elevation point and at a pumping rate that maintains the location and orientation of the bag, to the extent possible. Several Filling valves may be used to accomplish this purpose. Fine aggregate concrete shall be pumped in such a way that excessive pressure on the fabric forms is avoided.

SECTION 35 43 29 Page 15

Foot traffic on the filled concrete grout bag units shall be restricted to an absolute minimum for the first hour after filling, except to install dowels or rebar, as specified herein.

Abutting or lateral concrete grout bags, either individual or part of the grout bag panel, may be installed immediately after placement of the preceding grout bag(s). If a concrete grout bag is to bear on a previously installed grout bag (i.e., installed at a higher elevation up the slope, the lower grout bag shall be allotted a minimum of four hours of cure time before beginning installation of a higher elevation, vertically adjacent grout bag(s).

Grout bag panels shall require connection of the cables that are parallel to the direction of flow and that extend through the grout bags. The cables shall be connected using a swage, or an equivalent method selected by the Contractor and approved by the Contracting Officer. The connection shall be performed after grout bags for an entire panel have been filled and prior to any grout placed into the grout bag of an adjacent panel.

After securing the cables taut, the connection shall be compressed between the grout bags of adjacent panels. Cables connecting panels and extending perpendicular to the direction of flow do not require connection to adjacent panels.

No sooner than one-half hour but no later than one hour after fine aggregate concrete has been placed in a grout bag, dowels or rebar to connect the tie-in element to the grout bags shall be inserted vertically into the bags at the locations shown on the drawings or as directed by the Contracting Officer. The dowels shall be forced through the top surface of the grout bag to the depths indicated on the drawings and allowed to extend upward from the grout filled bag. The length of extension shall be as shown on the drawings. The exposed end of dowels and rebar shall be temporarily capped to reduce risk of impalement and to reduce sharp edge exposure until the grout for the tie-in element is ready for placement. The method of driving the dowels shall be selected by the Contractor and approved by the Contracting Officer.

Not more than two (2) days after grouting is completed for a grout bag panel, the Contractor shall perform measurements to verify that the grout bag scour protection installation meets the tolerances outlined in paragraph "Construction Tolerances". These measurements shall be performed for each grout bag panel installed.

3.3.5 Cast-In-Place Apron Tie-In Element

The cast-in-place apron tie-in element shall be constructed no sooner than 24 hours after the grout bag base has been installed. Formwork for the cast-in-place apron tie-in element shall be installed to meet the lines and grades of the element shown on the drawings and in accordance with paragraph "Installation" of Section 03 11 14.00 10 FORMWORK FOR CONCRETE.

Formwork shall commence no sooner than one hour after the grout bag base has been completed. Prior to installation of any forms, the Contractor shall install a leveling plate on the grout bag base, to which the form can be secured and leveled. The leveling plate shall be installed no later than one hour after the filling of the grout bag base, so as to permit horizontal and vertical adjustment or "leveling" of the plate while the grout is still fluid in the bag. Any other preparatory work associated with the installation of forms for constructing the tie-in element shall be performed within the first hour of filling. Formwork shall be suspended

SECTION 35 43 29 Page 16 from the existing dam apron, however, drilling into the apron to secure the formwork shall only be permitted, with approval of the Contracting Officer.

Formwork may be secured to the leveling plate. Reinforcement for the apron tie-in element shall be installed in conjunction with the formwork. The reinforcing shall be installed as detailed on the drawings and in accordance with Section 03 20 02 STEEL BARS, WELDED WIRE FABRIC AND

ACCESSORIES FOR CONCRETE REINFORCEMENT.

Cast-in-place grout shall be pumped into the formwork using the procedures discussed herein. Pressure shall be monitored to prevent movement of the formwork. Opening in the top of the formwork shall be created to insert the pump hose into the cavity to be filled. The unit length of the apron tie-in element that is to receive cast-in-place grout in one application shall not be less than 18 feet, nor more than 24 feet, measured along the edge of the dam apron.

Forms shall be removed no sooner than 48 hours after grout has been placed.

3.4 COMMUNICATIONS

When, for his own convenience, the Contractor has the individual elements of his plant so located that communication by normal voice between these elements is not satisfactory, the Contracting Officer may require him to install a satisfactory mechanical means of communications, such as a two-way radio, cellular telephone or other suitable device.

3.5 CONTRACTOR QUALITY CONTROL

In accordance with Section 01 45 01 USACE QUALITY CONTROL, quality control shall be established and maintained. Inspections shall be conducted to verify that the tolerances specified above and the procedures identified in paragraph "Documentation" of Section 35 43 29.15 DEMONSTRATION PROJECT are being performed.

Inspections of the grout bag panels shall be performed by the Contractor under direct supervision of the Contracting Officer. A minimum of two (2) grout bags shall be inspected for each grout bag panel installed in the first two gate bays, as shown on the Stage 1 Grout Bag Plan drawing. One grout bag shall be inspected for each grout bag panel installed in all other gate bays, as shown on the Stage 2 through 6 Grout Bag Plan drawings. The frequency of inspection may be adjusted by the Contracting Officer, if necessary.

3.6 ENVIRONMENTAL RESTRICTIONS

The Contractor shall use procedures to minimize or avoid environmental impacts due to grouting activities and to comply with applicable environmental regulations and requirements of Section 01 57 20.00 10 ENVIRONMENTAL PROTECTION. The Contractor shall have full responsibility for violating any of the environmental regulations and requirements of Section 01 57 20.00 10 ENVIRONMENTAL PROTECTION, and associated fines.

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