Technical Manual

Inc.

p 183

APPENDIX 2F

MODEL SPECIFICATIONS

Chapter 2

Helical Foundation Systems

11.9.4 When the final installation torque readings at the planned helical soil nail lengths do

not achieve the minimum final torque requirements per the design or Plans, the Owner

shall be notified to make recommendations for adding soil nails or extending the non-

conforming soil nail to greater lengths.

11.9.5 Helical soil nail installation shall be terminated when the planned length is achieved

as long as the final installation torque requirements per the design are met. When the

maximum torque rating of the helical soil nail shaft is achieved prior to reaching the

design length, the Soil Nail Designer shall be notified to make design recommendations

to the Owner.

11.9.6 The installation of the helical soil nails shall be made at the locations, inclinations, and

lengths shown on the Plans or as directed by the Owner. The installation techniques

and equipment used shall be such that it is consistent with the geotechnical, logistical,

environmental, and load carrying conditions of the project.

11.9.7 The helical soil nail sections shall be engaged and advanced into the soil in a smooth,

continuous manner at a rate of rotation less than 25 rpm. Sufficient crowd shall be

applied to advance the helical soil nail sections at a rate approximately equal to the

pitch of the helix plate per revolution. The rate of rotation and magnitude of crowd

shall be adjusted for different soil conditions and depths. Extension sections shall be

provided to obtain the required minimum overall nail length.

11.9.8 Helical soil nails that encounter unanticipated obstructions during installation shall be

relocated as approved by the Owner’s representative.

INSTALLATION RECORD SUBMITTALS

12.1 The Installing Contractor shall provide the Owner, or his authorized representative, copies of

individual helical soil nail installation records within 24 hours after each soil nail installation

is completed. Formal copies shall be submitted within 30 days following the completion of

the helical soil nail installation. These installation records shall include the information listed in

Section 11.9.3.

HELICAL SOIL NAIL TESTING

13.1 If helical soil nail testing is required, the Installing Contractor shall furnish all labor, equipment

and pre-production helical soil nails necessary to accomplish the testing as shown in the

approved soil nail design documentation. Installing Contractor shall apply the specified loads

for the specified durations and record the specified data, for the specified number of soil nails.

No deviations from the test plan(s) will be allowed without explicit approval in writing from the

Owner. Testing of any helical soil nail shall not be performed until the shotcrete facing has

cured for at least 72 hours or attained at least the specified 3-day compressive strength. Helical

soil nails may be tested immediately after installation without a shotcrete facing as long as

precautions to maintain face stability are made (i.e., temporary lagging, etc.).

13.2 The test equipment shall consist of:

13.2.1 A calibrated dial gauge capable of measuring to 0.001 inch shall be used to measure

movement.