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-2.04 PAYMENT Not Used 46-3 SOIL NAILS 46-3.01 GENERAL



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46-2.04 PAYMENT


Not Used

46-3 SOIL NAILS

46-3.01 GENERAL

46-3.01A Summary


Section 46-3 includes specifications for constructing soil nails.

A soil nail consists of steel bar reinforcement with an anchorage assembly that is placed in a drilled hole and then grouted.


46-3.01B Definitions


pullout failure: Occurrence in which attempts to increase the test load result in nail head movement relative to a fixed reference point without an increase in load.

46-3.01C Submittals

46-3.01C(1) General


If a pullout failure occurs, submit the pullout failure load as part of the test data.

If production soil nails are rejected under section 46-3.01D(2)(b)(ii)(3), submit revised shop drawings.

If additional verification soil nails are required under section 46-3.01D(2)(b)(ii)(2), submit revised shop drawings.

46-3.01C(2) Test Boring Report


If additional verification soil nails are required under section 46-3.01D(2)(b)(ii)(2), submit a test boring report for the additional verification soil nails.

The test boring report must include:

1. Summary of drilling methods, drilling equipment, drill platforms, and drilling difficulties encountered

2. Location map of the surveyed position of the new test borings relative to existing and proposed facilities in the California Coordinate System and bridge stationing

3. Bore hole surveying notes

4. Depth increments of borings

5. Soil and rock classifications and descriptions

6. Photographs of cuttings

7. Copies of original daily drilling notes, including dates and weather conditions
Classify soil and rock under the Soil and Rock Logging, Classification, and Presentation Manual. For the manual, go to the Geotechnical Services Web site.

The test boring report must be sealed and signed by a geologist or engineer registered as a geologist or civil engineer in the State.


46-3.01D Quality Assurance

46-3.01D(1) General


Not Used

46-3.01D(2) Quality Control

46-3.01D(2)(a) General

Not Used
46-3.01D(2)(b) Load Testing
46-3.01D(2)(b)(i) General

Perform load testing of verification and proof test soil nails to verify the installation methods and pullout resistance.

Load testing must include incrementally loading the soil nail until the maximum test load is held for the specified duration or a pullout failure occurs. If a pullout failure occurs, record the pullout failure load.


46-3.01D(2)(b)(ii) Test Procedure

46-3.01D(2)(b)(ii)(1) General

Determine the test load using the following equation:

T = Lb x Qd
where:

T = test load, pounds

Lb = soil nail bonded length, feet, 10 feet minimum

Qd = design pullout resistance shown, pounds/foot


46-3.01D(2)(b)(ii)(2) Verification Test

Perform verification testing in the Engineer's presence.

Install and test 2 verification test soil nails for each wall zone. You may install and test the nails during stability testing.

Conduct the verification test as follows:

1. Incrementally load the test soil nail as shown in the following table:


Verification Test Loading Schedule

Load increment

Hold time (minutes)

AL

Until stable

0.20T

1–2

0.40T

1–2

0.60T

1–2

0.80T

1–2

1.00Ta

60

1.25T

1–2

1.50Tb

10

AL

Until stable

NOTE: T = test load

AL = alignment load = 0.10T



aCreep test

bMaximum test load

2. Apply each load increment in less than 1 minute and hold it for the length of time shown in the table titled "Verification Test Loading Schedule."

3. Measure and record the applied test load and the nail head movement at each load increment.

4. During the creep test:

4.1. Hold the load constant for 60 minutes.

4.2. Start the observation period for the load hold when the pump starts to apply the load increment from 0.80T to 1.00T.

4.3. Measure and record the nail head movement at 1, 2, 3, 4, 5, 6, 10, 20, 30, 40, 50, and 60 minutes.

4.4. Plot a creep curve as a function of the logarithm of time, showing the nail head movement from 6 to 60 minutes.

5. If the movement measured from 6 to 60 minutes is less than 0.08 inch:

5.1. Increase the load incrementally to 1.50T.

5.2. Hold the load constant for 10 minutes.

5.3. Start the observation period for the load hold when the pump starts to apply the load increment from 1.25T to 1.50T.

5.4. Measure and record the nail head movement at 1, 2, 3, 4, 5, 6, and 10 minutes.

5.5. Reduce the load to the ending alignment load and record the residual movement.

6. If the movement measured from 6 to 60 minutes is 0.08 inch or greater, reduce the load to the ending alignment load.


Verification test soil nails that fail to comply with the acceptance criteria are rejected.

Submit revised shop drawings for additional verification test soil nails.

The Engineer determines the cause of failure for each rejected verification test soil nail.

If the Engineer determines that the installation methods are the cause of failure, the installation methods are rejected. Show alternative installation methods on the revised shop drawings.

If the Engineer revises soil nail lengths or design pullout resistance values, any additional verification test soil nails are change order work.

Install and test additional verification test soil nails until they comply with the acceptance criteria.

Log horizontal borings for additional verification test soil nails and submit a test boring report under section 46-3.01C. The logging of horizontal test borings and the submittal of the test boring report is change order work.

46-3.01D(2)(b)(ii)(3) Proof Test

Production soil nails must be represented by proof test soil nails within a given wall zone.

Perform proof testing in the Engineer's presence at the locations shown.

Test against a temporary yoke that bears directly on the shotcrete facing. Test loads transmitted through the temporary yoke must not fracture the shotcrete or cause displacement or sloughing of the soil surrounding the drilled hole.

Conduct the proof test as follows:

1. Incrementally load the test soil nail as shown in the following table:




Proof Test Loading Schedule

Load increment

Hold time (minutes)

AL

Until stable

0.20T

1–2

0.40T

1–2

0.60T

1–2

0.80T

1–2

1.00Ta,b

10 or 60

1.25Tc

1–2

1.50Tc

1–2

AL

Until stable

NOTE: T = test load

AL = alignment load = 0.10T



aCreep test

bMaximum test load for proof test

cLoads for supplemental testing only

2. Apply each load increment in less than 1 minute and hold it for the length of time shown in the table titled "Proof Test Loading Schedule."

3. Measure and record the applied test load and the nail head movement at each load increment.

4. During the creep test:

4.1. Hold the load constant for 10 minutes.

4.2. Start the observation period for the load hold when the pump starts to apply the load increment from 0.80T to 1.00T.

4.3. Measure and record the nail head movement at 1, 2, 3, 4, 5, 6, and 10 minutes.

5. If the movement measured from 1 to 10 minutes is greater than 0.08 inch:

5.1. Hold the load constant for an additional 50 minutes.

5.2. Measure and record the nail head movement at 20, 30, 40, 50, and 60 minutes.

5.3. Plot a creep curve as a function of the logarithm of time, showing the nail head movement from 6 to 60 minutes.

6. Reduce the load to the ending alignment load and record the residual movement.
Production soil nails represented by proof test soil nails that fail to comply with the acceptance criteria, except those represented by proof test soil nails selected for supplemental testing, are rejected.

Submit revised shop drawings for replacement soil nails that show alternative installation methods, revised production soil nails, or a modified soil nail plan.



46-3.01D(2)(b)(ii)(4) Supplemental Test

The Engineer selects up to 1/2 of proof test soil nails for supplemental testing. Only proof test soil nails with a creep movement less than 0.08 inch measured from 1 to 10 minutes are considered for supplemental testing.

Perform supplemental testing immediately following creep testing. Incrementally load the soil nails as shown in the table titled "Proof Test Loading Schedule." Record the test load and nail head movement as part of the test data.

For proof test soil nails that fail supplemental testing, the Department deducts $1.00 per linear foot of proof test soil nail.


46-3.01D(2)(c) Grout

Before using grout with fine aggregate, produce a test batch to verify the consistency. Produce and deliver the test batch under conditions and in time periods similar to those expected during the grouting of soil nails.

Place the test batch grout in an excavated hole or a container of suitable size to allow testing under California Test 533. The test batch must comply with the specified nominal penetration.

Dispose of the grout after testing.

46-3.01D(3) Department Acceptance

46-3.01D(3)(a) General

The Department tests grout with fine aggregate under California Test 533 before use.
46-3.01D(3)(b) Load Testing
46-3.01D(3)(b)(i) General

Not Used
46-3.01D(3)(b)(ii) Acceptance Criteria

Soil nails that are verification- or proof-tested must comply with the following:

1. For verification tests:

1.1. Creep movement measured from 6 to 60 minutes is less than 0.08 inch.

1.2. Creep rate is linear or decreasing in time logarithmic scale from the 6- to the 60-minute reading.

2. For proof tests, the creep movement complies with one of the following:

2.1. Creep movement measured from 1 to 10 minutes is no more than 0.08 inch.

2.2. Creep movement measured from 6 to 60 minutes is less than 0.08 inch and the creep rate is linear or decreasing in time logarithmic scale from the 6- to the 60-minute reading.

3. Total measured movement at the maximum test load minus the measured residual movement at the ending alignment load exceeds 80 percent of the theoretical elastic elongation of the unbonded length.

4. Pullout failure does not occur.



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