140R3025R0014_Attachment_1b_-_Hoover_Rockfall_Mitigation_IDIQ_SOW_-_Appendices.pdf

Appendix A

MATERIALS

1. Rock Bolts

a. Shall conform to ASTM A722.

b. Shall have a minimum ultimate tensile strength level of 1035 MPa (150000 psi.).

c. Shall be coated with a color that blends in with the surrounding rock.

d. Engineered approved equal.

2. Stainless Steel Cable

a. Shall have a minimum ½” diameter.

b. Shall have a minimum break strength of 22,000 lbs.

c. All cable that is visible to the public will be coated with a color that blends in with the surrounding rock.

d. Engineered approved equal.

3. 3 mm Mesh

a. Shall be steel wire mesh with corrosion protection.

b. Number of meshes longitudinal shall be 7 pieces per 3.28 feet.

c. Number of meshes transversal shall be 12 pieces per 3.28 feet.

d. In circle diameter of mesh shall be a maximum of 2.56 in. (+/-3%).

e. Steel wire

f. Shall have minimum diameter of 0.118 inches.

g. Shall be made of high-tensile carbon steel.

h. Shall have minimum tensile strength of 256 ksi.

i. Corrosion protection shall be made of 95% Zn and 5% Al compound.

j. Shall have a minimum tensile strength of 10.3 kips/ft.

k. All meshing shall be anchored at 5 to 10 ft. on center.

l. All mesh that is visible to the public will be coated with a color that blends in with the surrounding rock.

m. Engineered approved equal.

4. 4 mm Mesh

a. Shall be steel wire mesh with corrosion protection.

b. Number of meshes longitudinal shall be 7 pieces per 3.28 feet.

c. Number of meshes transversal shall be 12 pieces per 3.28 feet.

d. In circle diameter of mesh shall be a maximum of 2.52 in. (+/-3%).

e. Steel wire

i. Shall have minimum diameter of 0.157 inches.

ii. Shall be made of high-tensile carbon steel.

iii. Shall have minimum tensile strength of 256 ksi.

f. Corrosion protection shall be made of 95% Zn and 5% Al compound.

g. Shall have a minimum tensile strength in the longitudinal direction of 12.1 kips/ft.

h. Shall have a minimum tensile strength in the transversal direction of 4.6 kips/ft.

i. All meshing shall be anchored at 5 to 10 ft. on center.

j. All mesh that is visible to the public will be coated with a color that blends in with the surrounding rock.

k. Engineered approved equal.

5. Spiral Mesh

a. Shall be steel wire mesh with corrosion protection.

b. Number of meshes longitudinal shall be 2 pieces per meter.

c. Number of meshes transversal shall be 3.4 pieces per meter.

d. In circle diameter of mesh shall be a maximum of 230 mm. (+/-5%)

e. Steel wire

i. Shall have minimum diameter of 4 mm.

ii. Shall be made of high-tensile carbon steel.

iii. Shall have minimum yield point of 1770 N/mm2.

f. Corrosion protection shall be made of 95% Zn and 5% Al compound.

g. Shall have a minimum tensile strength of 220 kN/m.

h. All meshing shall be anchored at 5 to 8 ft. on center.

i. All mesh that is visible to the public will be coated with a color that blends in with the surrounding rock.

j. Engineered approved equal.

6. Anchors For Mesh

a. Shall be installed according to specifications provided by mesh manufacture.

b. Specifications shall be provided by manufacturer of mesh.

7. Rockfall Barrier System (Rockfall Fence)

a. All structural steel components, including anchors and clamps, shall conform to the requirements in ASTM Designation A36.

b. All bolts, nuts, and washers shall conform to the requirements in ASTM Designation A325 and as required to conform to the tested rockfall barrier kit.

c. Ring Net: Ring net shall be defined as fabric consisting of interlocking steel rings with a diameter of no more than 14 inches. Each ring shall connect to the four or six adjoining rings by passing through them; they must be interlocked. Individual rings shall be fabricated from high tensile steel wire with a nominal steel wire diameter of .12-inch (3

mm) with a minimum breaking strength of 198,700 psi. For a type I or type II fence nominal steel wire diameter of 0.07-in (2 mm) with minimum wire breaking strength of 198,700 psi shall be allowed. A minimum of 5 strands shall be bundled into each ring.

Steel wire used in the fabrication of the ring net shall be galvanized.

d. Cable Net / Woven Wire Rope Net: Cable/Woven wire rope nets shall have a uniform grid pattern, shall be constructed of galvanized aircraft cable, with a square or diamond weave, and must have no more than a 12 inch opening size. Nominal opening size for cable nets/wire rope nets may be specified on the contract documents as 6, 8, 10 or 12 inches. Connectors used to fasten adjacent panels shall have a connection strength equal to or greater than the connection strength of the net.

e. High Tensile Wire Mesh: High tensile wire mesh shall be of woven construction with a minimum nominal wire diameter of at least 0.15-inch (4-mm). The wire shall have ends formed into a loop and twisted with loops fastened together to prevent unraveling of the mesh. This wire shall have a minimum of 250,000 psi breaking strength. The mesh shall have a minimum longitudinal tensile strength or load capacity of at least 10,000 lbs/ft.

f. Wire Mesh: When added to a rockfall barrier system, wire mesh shall be securely attached to the cable or ring net fence. Spacing of tie wire or connectors shall be in accordance with manufacturer’s recommendations. This mesh shall be flush with no gaps exceeding 4 inches. Tie wires or connectors used to fasten the wire mesh to the cable net of adjacent panels shall have a connection strength greater than or equal to the strength of the mesh.

g. Net Support Columns: Columns shall be fabricated from steel meeting ASTM A36 for preformed steel shapes except as otherwise approved in writing as part of an approved rockfall barrier system prior to letting of contract. Columns shall be as specified in the certified rockfall barrier kit equipment list and substitutions are not permitted unless columns for a higher capacity system by the manufacturer are substituted and the manufacturer certifies that the substitution is acceptable. Test results shall be required to prove that the system and columns are capable of resisting design loads as specified in general requirements above. Substitutions of different net support column members after contracts are issued shall not be allowed.

h. Net Support and Lateral Bracing Ropes: Braking element design shall have been verified through testing and certification of the rockfall barrier kit to ensure satisfactory performance and a minimum of required maintenance. Written documentation of testing of braking elements used with support or bracing ropes shall be supplied to the Engineer upon request.

i. Rock and Soil Anchors: Anchors in rock and soil shall be installed per manufacturer’s recommendations for the Rockfall Barrier kit and all anchors needed for rockfall barrier kit, including installation shall be included in the rockfall barrier price. Cable anchors shall have a minimum pullout strength of 15 tons (or more if required by specific manufacturer fence design) and must be verified by the contractor in the field. The testing shall consist of a pullout test incorporating 20% of the total number of anchors with locations chosen by the Engineer. If more than 25% of the anchors tested fail, all anchors shall be tested.

Failed anchors shall be replaced by the contractor at no additional cost to the owner.

Testing shall be performed against a temporary yoke or load frame. No part of the yoke or load frame shall bear within 3 feet of the anchor.

j. Miscellaneous Materials: All miscellaneous hardware such as wire rope clips, thimbles, bolts, shackles, etc. shall be supplied by the manufacturer with the rockfall barrier kit.

Shackles shall be used to fasten nets to each other and to the net support ropes, unless specifically not allowed by the manufacturer.

k. Corrosion Protection: All cables and wire ropes shall meet Federal Specification RR-W- 410 D or MIL-W-83420 E for zinc coating. All miscellaneous material associated with the rock fall barrier such as wire rope clips, bolts, nuts, thimbles, and shackles shall be at minimum hot dipped galvanized.

l. Concrete: The minimum concrete strength is to be 4,000 pounds per square inch or as specified.

m. Shall be installed according to specifications provided by the manufacture,

n. Specifications shall be provided by the manufacturer.

End of Appendix A

Appendix B

ROCK REINFORCEMENT

1. Measurement.

a. Drill Setups for Rock Bolts: Number of drill setups for permanent and temporary rock bolts.

b. Drill Setups for Rock Anchors: Number of drill setups for permanent and temporary rock anchors.

c. Permanent Rock Bolts: Length of permanent rock bolts installed.

d. Temporary Rock Bolts: Length of temporary rock bolts installed.

e. Permanent Rock Anchors: Length of permanent rock anchors installed.

f. Temporary Rock Anchors: Length of temporary rock anchors installed.

g. Double Twist Hexagonal Mesh Netting (DTHMN): Area of DTHMN fabric installed.

h. Drill Setups for Drain Holes: Number of drill setups for drain holes.

i. Drain Holes: Length of drain holes installed.

j. Rock Bolt Performance Tests: Total number of tests performed.

k. Rock Anchor Performance Tests: Total number of tests performed.

2. References.

a. ASTM International (ASTM). For the ASTM standards below that do not include a date the current version should be used.

ASTM A 615/A 615M-08 Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement

ASTM A 603-98 (2003) Zinc-Coated Steel Structural Wire Rope ASTM A 722/A 722M-07 Uncoated High- Strength Steel Bar for Prestressed

Concrete ASTM A 975-97 (2003) Double-Twisted Hexagonal Mesh Gabions and

Revet Mattresses (Metallic-Coated Steel Wire or Metallic-Coated Steel Wire with Poly (Vinyl Chloride (PVC) Coating)

ASTM C 494/C 494M-08 Chemical Admixtures for Concrete ASTM D 1785-06 Poly(Vinyl Chloride) (PVC) Plastic Pipe, Schedule 40, 80, and 120 ASTM D 2665-07 Poly(Vinyl Chloride) (PVC) Plastic Drain, Waste, and Vent Pipe and Fittings ASTM F 432-04 Roof and Rock Bolts and Accessories

b. Post-Tensioning Institute (PTI).

PTI Recommendations for Prestressed Rock and Prestressed Rock and Soil Anchors, Fourth Edition, 2004 Anchors

3. Submittals.

a. Manufacturer’s Product Data:

i. Type and details of steel bars to be used for rock bolts and rock anchors.

ii. Manufacturer’s recommendations for installation.

iii. Type and details of rock bolt accessories.

iv. Equipment and procedures for drilling rock bolt and rock anchor holes, including hole diameter and quality control procedures to achieve specified verticality tolerances.

v. Equipment and procedures for rock bolt installation.

vi. Equipment and materials for encapsulation grouting.

b. Rock bolt and rock anchor certification:

Certification from manufacturer that steel components of rock bolt and rock anchor system meet or exceed these specifications.

c. Rock and anchor bolt plan:

i. Equipment used to drill holes, seat and tighten rock bolts or establish anchorage in hole, tighten bolt to required tension and encapsulation grouting.

ii. Components of rock bolt assembly, including bolts, nuts, anchor plates, beveled or hemispherical washers, couplers, centralizers, and resin.

iii. Manufacturer’s instructions for installing and anchoring.

d. Testing Information:

i. Proposed equipment and test setup for performance testing rock bolts and rock anchors. Include details of tensioning equipment, measurement of rock bolt/anchor load, and measurement rock bolt/anchor displacement.

ii. Tensioning:

(1) Include certification of calibration for load application and measuring system to be used for the rock bolt/anchor testing.

(2) Records and logs of rock bolt/anchor tensioning and performance tests results within 24 hours of test completion or prior to grouting.

(3) Include rock bolt/anchor hole location, hole diameter, and comparisons of test results with expected behavior.

e. Records - Data plots: Data plots from load and elongation measurements during performance tests.

f. Resin Cartridges Material Approval Data:

g. Cement Grout Material Approval Data:

i. Mix design for cement grout.

ii. Manufacturers’ certifications and test reports for type of material.

iii. Grout equipment and configuration.

iv. Pump rating curves and complete mixer details, including photographs of the proposed mixing equipment.

4. Storage and Handling.

a. Ship, handle, and store the rock bolts and accessories to prevent damage. Protect from exposure to dirt and water.

b. Store in a dry, ventilated place, heated if necessary to prevent accumulation of moisture on the materials.

c. Do not store directly on the ground.

d. Resin cartridges:

i. Store in well ventilated, dry area, protected for excessive heat and cold.

ii. Do not exceed manufacturer’s recommended shelf life.

iii. Do not use cartridges that show signs of damage, hardness, or other indications of deterioration.

e. Bolts and nuts:

i. Protect threads from damage.

ii. Repair or replace rock bolt components damaged due to shipping, neglect, or handling.

f. Rock bolts: Repair or replace rock bolts with rusting sufficient to cause excessive surface roughness, pitting visible to the naked eye, or surface damage or unevenness.

g. Rock anchors: Repair or replace rock anchors with rusting sufficient to cause excessive surface roughness, pitting visible to the naked eye, or surface damage or unevenness.

5. Products.

a. Rock Bolts

i. Permanent Rock Bolts:

(1) Two-stage resin anchored, fully-cement grouted rock bolts:

(2) Steel: ASTM A 615 (Grade 60) or ASTM A 722 nominal diameter: as shown on the drawings.

(3) Rolled threads to allow direct pull tensioning of bar.

(4) Length: working length, as shown on the drawings, not including length of anchorage as recommended by manufacturer.

ii. Temporary Rock Bolts:

(1) Resin-grouted end anchor zone type rock bolts

(2) Steel: ASTM A 615 (Grade 60) or ASTM A 722.

(3) Nominal diameter: As shown on the drawings.

(4) Rolled threads to allow direct pull tensioning of bar.

(5) Length: working length, as shown on the drawings, not including length of anchorage as recommended by manufacturer.

iii. Bearing plates, washers, nuts, couplers, and accessories for rock bolts and anchors:

(1) ASTM F 432.

(2) Bearing plates:

a) Thickness: As recommended by rock bolt system manufacturer to meet design load requirements of bolt.

b) Area, minimum: square inches for each bolt, as recommended by manufacturer.

iv. Washers:

(1) Beveled or hemispherical

(2) Steel or malleable iron.

(3) Machine washers:

a) Hardened steel.

b) Hemispherical washers not required.

v. Nuts: Manufacturer's heavy hexagonal type.

vi. Centralizers:

(1) Recommended by bolt manufacturer for bolt type and diameter.

(2) Plastic-coated.

(3) Designed to allow free travel of grout along the length of the rock bolt.

vii. Mechanical Couplings:

(1) Recommended by bolt manufacturer for bolt type and diameter.

(2) Grout and vent tubes: Heavy duty plastic tubes.

b. Permanent Rock Anchors - Fully-cement grouted rock anchors:

i. Steel: ASTM A 615 (Grade 60) or ASTM A 722.

ii. Nominal diameter: As shown on the drawings.

iii. Rolled threads to allow direct pull testing of bar.

c. Temporary Rock Anchors - Resin cartridge grouted type rock anchors:

i. Steel: ASTM A 615 (Grade 60) or ASTM A 722.

ii. Nominal diameter: As shown on the drawings.

iii. Rolled threads to allow direct pull testing of bar.

d. Mesh Netting

i. Double Twist Hexagonal Mesh Netting (DTHMN):

(1) DTHMN: ASTM A 975:

(2) Type 8x10 mesh.

(3) Wire: 0.106-inch Diameter.

(4) PVC Coated.

ii. Wire rope:

(1) ASTM A 603.

(2) Galvanized.

e. Resin Cartridges - Resin grout:

i. Manufacturer’s recommended viscosities and setting times of resin cartridges for expected temperature ranges.

ii. Fast setting resin for rock bolts and rock anchors.

iii. Slow setting resin for rock bolts and rock anchors.

f. Cement Grout for Encapsulation

i. Portland Cement: ASTM C150, Type II.

ii. Water: ASTM C 1602.

iii. Allowable Chemical Admixtures:

(1) High Range Water-Reducing Agent (HRWRA): ASTM C494, Type F.

(2) Meyco Fix Flowcable manufactured by BASF Admixtures Inc., 23700

Chagrin Boulevard, Cleveland OH 44122 (216-839-7500); or equal, having the following salient characteristics:

a) Salient Characteristics: High water reducing.

b) Shrinkage compensating.

c) High early strengths. Do not use chemical admixtures which contain more than 0.1 percent chloride, by weight.

d) Offerors proposing to furnish an "equal" product, in accordance with the "Brand Name or Equal" provision of this solicitation, shall insert the following description for the product.

e) Product Name: Manufacturer's Name: Address:

f) Product Make, model, or Catalog Description:

iv. Mix:

(1) Water-cement ratio, maximum by volume, not greater than 0.7 to 1.

(2) Results from tests performed with the HRWRA or Flowcable sample shall be used to determine the grout mix.

a) Use according to manufacturer’s instructions

b) For HRWRA, dose at .5% to 1% by weight of cement.

c) If necessary, add no more than ½ of HRWRA to mix water before adding cement. Add rest of HRWRA after cement and water have been mixed.

d) If the use of HRWRA chosen by the Contractor is accompanied by abnormal setting of the fresh grout or if the HRWRA does not perform in accordance with these specifications, the Contractor shall furnish and use other brands of HRWRA until an acceptable admixture is found.

e) For Flowcable, proportions to be according to manufacturer’s instructions.

(3) Use of an accelerant is not allowed.

(4) Weighing, mixing and placing of the grout to be performed only in the presence of the COR.

(5) The COR will determine the usable time allowed before grout injection.

Depending on water-reducing agent, usable time allowed before grout injection will vary.

(6) Discard batch if too much time has elapsed between mixing of the grout and injection, as determined by the COR.

g. Equipment for Backfill Grouting:

i. All plant and equipment required to mix and pump the grout shall be furnished by the Contractor.

ii. The apparatus for mixing and placing grout, including circulating line and fittings, shall be of a type and size approved by the COR and shall be capable of effectively mixing and stirring the grout and forcing it into the grout holes or grout connections in a continuous, uninterrupted flow.

iii. Water supply to the mixer shall be adequate at all times to provide the required pumping rate.

iv. The grout mixing tank shall be cylindrical, mounted vertically, and shall be of the high-speed colloidal type equipped with a high-speed, diffuser-type centrifugal mixing pump operating at 1,500 to 2,000 revolutions per minute during mixing, that delivers grout at 30 pounds per square inch

v. Water used for grout shall be accurately measured to one-tenth of a cubic foot, and error shall not exceed 1 percent.

vi. The return flow from the centrifugal mixing pump shall be directed tangentially into the vertically mounted cylindrical tank near the top to create a vortex. In addition to the grout mixer, a holdover mechanical agitator tank similar in volume to the mixer shall be provided.

vii. The grout shall be placed with a helical-screw, rotor-type pump that produces flow with minimum pulsation. The pump shall have a minimum capacity of 35 gallons per minute at a pressure of 200 pounds per square inch. The grout pump shall be connected directly to the holdover mechanical agitator tank. Pumps with holding hoppers and pumps with open-throat suction housings and suction housing hoppers are not acceptable. Pump rating curves and complete mixer details, including photographs of the proposed mixing equipment, shall be submitted to the COR 30 days prior to use.

viii. The arrangement of the grouting equipment shall be such as to provide for circulating grout from the agitator tank through the grout pump to the manifold at the injection port, and then through a return line back to the agitator tank. A number 16 sieve size screen will be placed such that the grout exiting the return line will flow through the screen just prior to entering the agitator tank. Ensure that the screen stays free of debris. The minimum size of the grout supply line from the grout pump to the manifold and the manifold valves shall be 1 inch inside diameter. The manifold consisting of a series of valves, pressure gauge, and gage saver as shown on drawing 296-D-1213 shall be provided by the Contractor. Pressure gauges shall be equipped with approved gauge savers when pumping grout, and the gauges, with attached gauge savers shall be checked at least once per shift to assure their accuracy. The gauge savers shall be mounted in the manifold in the flow pattern behind the pressure control valve and ahead of the pressure bleed-off valve. Defective gauges or gauges with broken glass faces shall be replaced immediately. An accurately calibrated gauge test apparatus, including a high precision master gauge shall be provided by the contractor for periodic checking of the accuracy of all gauges used in the grouting. All pressure gauges for use in grouting shall be glycerin filled, plain case, with pressure indicated in psi and with a minimum dial face size of 2 ½ inch diameter. The rating of each pressure gauge shall not be more than 3 times the pressure at which the grout is anticipated to be pumped. All gauges shall be accurate to no more than 2 percent error over the full range of the gauge. All valves shall have minimum 6 inch lever handles permanently fixed to the valves that clearly show the position of the valve. Only cast iron or steel bodied valves are acceptable. The COR shall have the right to require the Contractor to make changes in the equipment which the COR determines necessary to make the equipment perform satisfactorily during grouting operations without additional cost to the Government.

6. Drain Pipe.

a. Schedule 40 slotted PVC pipe.

b. ASTM D 1785 and D 2665.

c. Slots as noted on drawings.

7. Execution.

General. If the rock anchorage method for rock bolts or rock anchors selected by the Contractor fails to provide satisfactory anchorage or fails to support rock loads as determined by the COR, the Contractor will be required to change to another type or method of rock anchorage at Contractor’s expense. Install permanent and temporary rock bolts and rock anchors with DTHMN at locations as shown on the drawings and as directed by the COR.

8. Permanent Rock Bolt Installation.

a. Two-stage fully encapsulated rock bolt:

i. Bond length – fast setting resin cartridge.

ii. Working length – cement grout.

iii. Clean surfaces of loose material and debris prior to installation.

iv. Drill hole in accordance with manufacturer’s instructions.

v. Prior to rock bolt installation, clean drilled hole of drill cuttings, sludge, and debris with water before bar is inserted.

vi. For fully grouted permanent rock bolts use a fast setting resin for bond length.

vii. Install fast setting resin cartridges according to manufacturer’s instructions.

viii. vii. Install rock bolts according to manufacturer's instructions at locations and at lengths indicated on Drawings.

ix. Field cut by sawing the threaded section of the rock bolt with a portable band saw or cut with an abrasive cutoff wheel that will not generate overheating of the area of the rock bolt where internal threaded tension components are used.

Torch cutting not permitted.

x. Do not weld the rock bolts, mechanical couplings or other rock bolt hardware.

xi. Do not unduly force or impact rock bolts into the drilled holes, which could cause abrasive damage to sleeves, or the exposed threaded section of the rock bolt.

xii. Keep rock bolt threads free from rust, burrs, and foreign matter.

xiii. Place rock bolts into the hole with at least three equally spaced centralizers within the working length and accessories as recommended by bolt manufacturer, to ensure correct centering alignment.

xiv. Repair rock bolts that have been damaged or made ineffective by excavation operations. If necessary, install additional bolts to replace damaged or ineffective bolts, at the Contractor’s expense.

b. Tensioning Rock Bolts:

i. Provide and maintain in good working condition the necessary hydraulic jacks, and related equipment for tensioning rock bolts and conducting performance tests.

ii. Allow for sufficient time for resin anchor grout to reach the required strength before tensioning rock bolts.

iii. Tighten each rock bolt with a center-pull hydraulic rock bolt tensioner.

iv. Use tensioner that has certified calibration within last 12 months.

v. For those bolts that will not be tensioned under a performance test, stress bolts to the maximum jacking test load of 80 percent of the yield of the rock bolt. Lock off at the transfer load of 70 percent of the yield. Reduced loads may be permitted in certain rock types as determined by COR. Measurement of bolt elongation will not be required for bolts not tensioned under a performance test.

vi. Replace rock bolts that fail to hold 80 percent of the yield load. If due to poor installation, as determined by COR, replace at the Contractor’s expense.

c. Perform performance tests in accordance with requirements below.

d. Check tension on rock bolts that were tensioned more than 48 hours prior to the completion of second stage (working length) grouting.

e. Perform second stage (working length) encapsulation grouting only after the rock bolt has been tensioned and accepted by the COR.

f. Perform second stage grouting of the bar length after tensioning of the rock bolt.

g. Install additional rock bolts to replace damaged or ineffective bolts (that fail to hold load), as determined by the COR, at Contractor’s expense.

9. Temporary Rock Bolt Installation.

a. Bond length – fast setting resin cartridge.

b. Working length – open or slow-setting resin as shown on the drawings.

c. Clean surfaces of loose material and debris prior to installation.

d. Drill hole in accordance with manufacturer’s instructions.

e. Prior to rock bolt installation clean hole of drill cuttings, sludge, and debris with water before bar is inserted.

f. For temporary rock bolts use a fast setting resin for anchor zone. The working length is to remain open or slow-setting resin as shown on the drawings.

g. Install fast setting resin cartridges according to manufacturer’s instructions.

h. Install temporary rock bolts according to manufacturer's instructions at locations and at lengths indicated on Drawings.

i. Field cut by sawing the threaded section of the rock bolt with a portable band saw or cut with an abrasive cutoff wheel that will not generate overheating of the area of the rock bolt where internal threaded tension components are used. Torch cutting not permitted.

j. Do not weld the rock bolts, mechanical couplings or other rock bolt hardware.

k. Do not unduly force or impact rock bolts into the drilled holes, which could cause abrasive damage to sleeves, or the exposed threaded section of the rock bolt.

l. Keep rock bolt threads free from rust, burrs, and foreign matter.

m. Place rock bolts into the hole with at least three equally spaced centralizers within the working length and accessories as recommended by bolt manufacturer, to ensure correct centering alignment.

n. Repair rock bolts that have been damaged or made ineffective by excavation operations.

If necessary, install additional temporary rock bolts to replace damaged or ineffective bolts.

o. Tensioning Rock Bolts:

i. Provide and maintain in good working condition the necessary hydraulic jacks, and related equipment for tensioning rock bolts and conducting performance tests.

ii. Allow for sufficient time for resin anchor grout to reach the required strength before tensioning rock bolts.

iii. Tighten each rock bolt with a center-pull hydraulic rock bolt tensioner. Use tensioner that has certified calibration within last 12 months.

iv. Stress bolts to the maximum jacking test load of 80 percent of the yield of the rock bolt. Lock off at the transfer load of 70 percent of the yield. Reduced loads may be permitted in certain rock types as determined by COR.

v. Replace rock bolts that fail to hold 80 percent of the yield. If due to poor installation, as determined by COR, replace at the Contractor’s expense.

p. Install additional rock bolts to replace damaged or ineffective bolts (fail to hold load), as determined by the COR.

10. Permanent Rock Anchor Installation.

a. Fully cement grout encapsulated rock anchor:

i. Entire length – cement grout.

ii. Resin grout – not permitted.

b. Clean surfaces of loose material and debris prior to installation.

c. Drill hole in accordance with manufacturer’s instructions.

d. Prior to rock anchor installation clean hole of drill cuttings, sludge, and debris with water before bar is inserted.

e. Install permanent rock anchor according to manufacturer’s instructions at locations and at lengths indicated on Drawings.

f. Field cut by sawing the threaded section of the rock anchor with a portable band saw or cut with an abrasive cutoff wheel that will not generate overheating of the area of the rock anchor where internal threaded tension components are used. Torch cutting is not permitted.

g. Do not weld the rock anchors, mechanical couplings or other rock anchor hardware.

h. Do not unduly force or impact rock anchors into the drilled holes, which could cause abrasive damage to sleeves, or the exposed threaded section of the rock anchors.

i. Keep rock anchors threads free from rust, burrs, and foreign matter.

j. Place rock anchor into the hole with at least three equally spaced centralizers and accessories as recommended by bolt manufacturer, to ensure correct centering alignment.

k. Do not tension rock anchors, except those anchors receiving a performance test.

l. For permanent rock anchors fully grout the entire length using cement grout.

m. Repair permanent rock anchors that have been damaged or made ineffective by excavation operations. If necessary, install additional anchors to replace damaged or ineffective anchors.

n. Perform pull tests on grouted rock anchors in accordance with requirements below.

o. Install additional permanent rock anchors to replace damaged or ineffective anchors (fail to hold load), as determined by the COR.

p. Temporary Rock Anchor Installation - Resign cartridge filled rock anchor:

i. Entire length – resin cartridges.

ii. Clean surfaces of loose material and debris prior to installation.

iii. Drill hole in accordance with manufacturer’s instructions.

iv. Prior to rock anchor installation clean hole of drill cuttings, sludge, and debris with water before bar is inserted.

v. For temporary rock anchors use sufficient amount of resin according to the manufacturer’s recommendation for the length and size of hole.

vi. Install rock anchor according to manufacturer’s instructions at locations and at lengths indicated on Drawings. Use enough fast setting resin cartridges to maintain anchor alignment.

vii. Field cut by sawing the threaded section of the rock anchor with a portable band saw or cut with an abrasive cutoff wheel that will not generate overheating of the area of the rock anchor where internal threaded tension components are used.

Torch cutting is not permitted.

viii. Do not weld the rock anchors, mechanical couplings or other rock anchor hardware.

ix. Do not unduly force or impact rock anchors into the drilled holes, which could cause abrasive damage to sleeves, or the exposed threaded section of the rock anchors.

x. Keep rock anchor threads free from rust, burrs, and foreign matter.

xi. Place rock anchor into the hole with at least three equally spaced centralizers and accessories as recommended by bolt manufacturer, to ensure correct centering alignment.

xii. Do not tension rock anchor.

xiii. Repair temporary rock anchors that have been damaged or made ineffective by excavation operations. If necessary, install additional temporary anchor to replace damaged or ineffective anchors.

xiv. Install additional temporary rock anchors to replace damaged or ineffective anchors (fail to hold load), as determined by the COR.

11. Hole Completion General.

a. Fast Setting Cartridge Installation in the Bond Length:

i. Place only after acceptance of the hole by the COR.

ii. Place fast setting cartridges to establish bond length according to the manufacturer’s recommendations.

iii. Carefully place cartridges into hole.

iv. Spin bolt/anchor 40-60 revolutions prior to beginning the countdown of temperature adjusted rated resin gel time.

b. Encapsulation Grouting of the Working Length:

i. Grout permanent rock bolt installations in two stages:

ii. Stage 1: Bond length. The bond length will be established initially after completion of the hole, cleaning and acceptance by the COR.

iii. Stage 2: Working length. Fully cement grouted following tensioning of rock bolt.

iv. Provide seal, air vent, and filling-grout tubes at the collar of the rock bolt hole to allow second stage cement grouting.

v. Allow the fast setting resin to cure for the appropriate time as established by the manufacturer’s instructions.

vi. Tension the rock bolt to the appropriate test load and lock off at the appropriate lock-off load.

vii. Perform second stage cement grouting of the working length only after the rock bolt has been tensioned and locked off at the appropriate load.

viii. Second stage grout the remainder of the installation, the working length, ensuring full return grout flow through the vent tube, to fully encapsulate with cement grout for the total length of installation.

12. Contractor Quality Testing.

a. Use a method for testing the rock reinforcement that includes the details of the test setup, tensioning equipment, frame, and systems for measurement of rock load and displacement. Meet the following minimum requirements:

i. Tensioning equipment: Use electrically-powered hydraulic tensioning equipment (jack, pump, and pressure gauge) having a load capacity between 125 percent and 200 percent of the maximum test load with sufficient travel to accommodate the full bar extension at the maximum test load.

ii. Load measurement: Use load cells or a calibrated pressure gauge with an accuracy of +/-1 kip (1,000 pounds) to measure the load on the bar. Provide a recent certified calibration curve (within the last 6 months) and calibrate for each load cell or jack. If the pressure gauge is mounted on the pump, then calibrate the jack and pump together as a unit. Conduct recalibration whenever required by the COR.

iii. Displacement measurement: Measure the displacement of the end of the bar with a dial indicator reading to 0.001 inch and having a minimum of 3 inches of travel. Mount the dial indicator on a fixed datum, which is independent of the tensioning system and frame. Displacement measurements which are not made from an independent fixed datum, such as measurement of ram extension, are not acceptable.

b. Performance tests for permanent rock bolts:

i. Perform all tests in the presence of COR.

ii. Follow the manufacturer’s recommendations and procedures for tests.

iii. Perform tests in accordance with the PTI Recommendations for Prestressed

Rock and Soil Anchors on rock bolts and selected by the COR.

iv. Collect at least seven load and elongation measurements during loading and unloading.

v. Plot data as shown for Plotting of Performance Test Data in accordance with PTI

Recommendations for Prestressed Rock and Soil Anchors.

vi. Tension to the test load, 80 percent of yield.

vii. After initial loading, hold the test load for 1 hour with movement less than 1/8-inch.

viii. Unload and record permanent movement.

ix. If deformations are excessive in the opinion of the COR, according to established

PTI guidelines, additional performance tests may be required.

c. Pull test for permanent rock anchors:

i. Perform all tests in the presence of COR.

ii. Follow the manufacturer’s recommendations and procedures for tests.

iii. Perform tests in accordance with the PTI Recommendations for Prestressed

Rock and Soil Anchors on rock bolts and selected by the COR.

iv.

v.

vi. Tension to the test load, 80 percent of yield.

vii. After initial loading, hold the test load for 1 hour with movement less than 1/8-inch.

viii. If load is not held according to established PTI guidelines replace anchor.

13. Drain Pipe Installation.

a. Drill hole as shown on drawings.

b. Install pipe in drilled holes. Friction fit is sufficient.

14. DTHMN Installation.

a. Place fabric at time rock reinforcement is installed.

b. Lap fabric section, minimum: 6 inches.

c. Place DTHMN fabric between rock surface and bearing plate.

d. Rock bolts recessed behind the plane of the DTHMN:

e. Obtain COR approval to not fasten DTHMN to rock bolt.

End of Appendix B