Pole Anchorage Information
Purpose: To ensure that the stock anchor bolt product is supplied with the approved packaging and materials.
Packaging: Each set of anchor bolts with the (ABSSS) suffix shall have the corresponding bolt circle template in plastic bag inserted in the box.
Bolts: Anchor bolts shall be manufactured to ASTM F1554 standards grade 55 (55,000 psi minimum yield strength; tensile strength of 75-95 ksi).
Anchor bolts shall be x” diameter, x” length, with an x” right angle hook at the unthreaded end, specific dimensions below. The bent portion of the anchor bolt shall be free from cracks when examined at a 10X magnification after bending. The straight end of the anchor bolt shall have 6” length of threads with 8 threads per inch. The threads shall be rolled and the body diameter shall not be less than the pitch diameter for the thread class 2A specified in ANSI/ASME B1.1. Thread acceptability shall be in accordance with ANSI/ASME B1.3.
A minimum of nine inches on 3/4" bolts and twelve inches on 1" or greater bolts of the straight-threaded end of the anchor bolt shall have a protective hot-dip galvanized coating. The hot-dip process shall be in accordance with the requirements of class C of ASTM specification A153.
Anchor bolts shall be commercially smooth and free of burrs, laps, seams, cracks, and other injurious manufacturing defects that would make them unsuitable for the intended application.
Hardware: Each anchor bolt shall have two nuts threaded onto them that conform to the requirements of ASTM specification A194 or A563 and be grade A heavy hex type, hot-dip or mechanically zinc coated in accordance with the requirements of class C ASTM specification A153. Nuts shall have a proof load stress equal to or higher than the minimum tensile strength specified for the anchor bolt.
Each anchor bolt shall also be furnished with two zinc-coated heat-treated flat washers that conform to the requirements of ASTM specification F436.
Using the correct anchor bolt template is critical when creating the foundation for all anchor base poles. Pole bases differ depending on pole shaft size, pole shaft shape and pole shaft material. The matrix below provides the critical dimensions required to set the AB’s correctly. The bolt circle is measured diagonally across the pole base, the base square is the outside measurement of the base plate and the anchor bolt projection is the amount of each AB that must be exposed above the final grade. These generic anchor bolt templates are to provide a guide when creating a template using the measurements from the table and should not be printed and used. The anchor bolt templates that are sent with the pole or anchor bolts will have the correct dimensions on the template. Always check to make sure you received the correct template based on the specific pole before use. When building the foundation for a Light Pole, it is very important to use the appropriately sized anchor bolts along with the correct anchor bolt template. All our anchor bolts and templates are in stock at our Distribution Centers and are available for next day shipping. Below is a quick reference guide to the anchor bolt template and anchor bolts that are to be used with each type pole.
Base and Poles
In 1985, the American Association of State Highway and Transportation Officials (AASHTO) revised their 1975 standard specification for breakaway pole performance. The vehicle test weight was lowered from 2250 lbs. to 1800 lbs. and the requirement was made for no more than 4” stub height to remain after the pole break away was added. Effective July 1, 1990, the Federal Highway Administration (FHWA) required that all unguarded poles used on highway projects receiving Federal funds, must meet this breakaway criteria. The following FHWA-approved breakaway devices meet those needs.
Anchor Base (Base Flange)
Breakaway anchor bases are available for 5”, 6”, 7” and 8” (0.156” wall only) poles. Applications for call box poles and post top mounted luminaire poles, to 30’ and 35’ mounting height, are available.
Three (3) breakaway transformer bases are currently available covering a wide range of pole sizes and bolt circle requirements. These bases are 17” high instead of the 20” height used in the past.
Breakaway couplings are available for 5/8", 3/4", 1" and 1-1/4" diameter anchor bolts and can be used for a wide range of pole sizes. Four-piece covers (skirts) are available for base flanges and other bases if an outline of the base is provided.
The X-Base is welded to the bottom of the pole shaft and serves as the base flange. It is supplied in one piece and bolts directly to the anchor bolts. The X-Base is available for 8” (0.188” wall and heavier), 9” and 10” diameter poles. Bolt circles are the same as our standard base flanges with some variations possible. Repair kits are available for possible reuse of pole after a knockdown.
Breakaway poles provide a safer outcome in the event of a collision. During an automobile collision, standard roadway lighting poles stay planted in the ground, letting the vehicle absorb a sizable amount of the energy. Breakaway poles fracture at ground level and yield out of the way of the vehicle. This allows the vehicle to pass through the pole and not absorb as much energy, reducing the severity of impact from the crash.
Aluminum Direct-Buried Breakaway Lighting Poles
Direct buried poles shall have a 1 ½” grommeted cable entry located 18” below grade, in line with the hand hole. An anti-rotational device shall be provided by means of partially flattening the butt of the pole into an oval cross-section, if specified. When ordering, it is important to specify that you need the breakaway-designed lighting pole.
The Federal Highway Administration (FHWA) accepts certain direct buried lighting poles for use on the National Highway System under the provisions of National Cooperative Highway Research Program (NCHRP) Report 350 “Recommended Procedures for the Safety Performance Evaluation of Highway Features.” Poles accepted for use on the National Highway System are required to meet appropriate evaluation criteria and are placed through rigorous impact testing procedures. For information regarding the specifications set forth by the Federal Highway Administration, visit the website: www.fhwa.dot.gov
Anchor Bolt Settings
When anchor bolts are set incorrectly, the pole will not mount properly to the foundation and the installer must consider different solutions to correct the problem. Options may include replacing the foundation; use of a special base adaptor; or, installation of epoxy set anchor bolts.
Replacing a foundation can be expensive or unrealistic on large projects. Base adaptors may not be possible for all conditions and are bulky, expensive and aesthetically unappealing. HILTI brand epoxy set anchor bolt systems offer a wide range of sizes and a technical support team for assistance. HILTI’s phone number is 800-879-8000. We can provide base reactions (shear force, axial force, bending moment and torsional moments occurring at the pole base used for foundation design) for the pole to assist HILTI technicians select the proper anchor bolt and epoxy formulation for the application. For base reactions, we will require the wind zone for the installation site and the total EPA and weight loading of the fixtures mounted on the pole.
Bolt Circle: Larger than Required
If the existing bolts were set to a larger bolt circle diameter and the pole has not been produced, it is possible to either:
1. Select a similar pole that has a properly matched bolt circle for the existing foundation.
2. Produce the original pole with a modified anchor base plate using the new bolt circle requirement without need of a base adaptor.
If the pole already exists, then the pole can be adapted to the new bolt circle using a custom-sized adaptor spool that installs between the pole base plate and the new bolt circle. Or the existing bolts can be cut off at the concrete surface and HILTI bolts installed.
Bolt Circle: Smaller than Required
If the existing bolt circle is smaller than that required for the pole to mount, care must be taken to ensure the foundation and anchor bolts are not overstressed through the use of an adaptor spool. In cases where the bolt circle is more than 1” smaller than that required for the pole, it may not be possible to provide an adaptor. These situations need to be carefully evaluated on a case by case basis.
When choosing between a base adaptor and the use of HILTI products, some considerations would involve size of anchor bolt, aesthetics, time and cost. The base adaptor method is rather expensive, involves more time to produce the adaptor and delays the project. Additionally, the spool increases the mounting height of the fixture which may violate local building codes—requiring the pole to be field-modified if necessary. Ultimately, the customer may not accept the “bulky look” of a base adaptor. One possible option to the base adaptor is the use of a standard Transformer Base. While it is bulky like the base adaptor, it does present a much cleaner, finished look and can be supplied faster than a custom manufactured adaptor when time is an issue.
The HILTI system provides a clean transition between the foundation and the pole. However, the HILTI bolts have to be set within, or close to, the foundation’s rebar for strength and to avoid cracking the edge of the foundation. If the foundation is undersized, use of HILTI products may not be possible. Also, HILTI bolts are only available up to 1.25” diameter so poles requiring larger diameter bolts will necessitate the use of an adaptor spool or replacement of the foundation.
Bolt Matrix with Generic Template