449Anchor Bolts

2.1 Bolts and Nuts . Provide bolts and nuts that meet the standards show n in Table 1.

Table 1 Bolt and Nut Standards Specified Anchor Bolt Category Bolt Standards Nut Standards Mild steel ASTM A307 Gr ade A, F1554 Grade 36, or A36 ASTM A563 Medium -strength, mild steel ASTM F1554 Gr ade 55 with supplementary requirement S1 ASTM A194 Gr ade 2 or A563 Gr ade D or better High-strength steel ASTM F3125 Grade A325 or ASTM A4491 ASTM A194 or ASTM A563, heavy hex Alloy steel ASTM A193 Gr ade B7 or ASTM F1554 Gr ade 105 ASTM A194 Grade 2H or ASTM A563 Gr ade DH, heavy hex 1. If headed bolts are specified, ASTM A449 bolts must be heavy hex head. Provide a mill test report or manufacturer’s certification indicating the material conforms to these requirements. For alloy steel anchor bolts, provide a test report or certification attesting to the heat -treating process if applicable. If no specific bolt category is shown on the plans, provide mild steel anchor bolts and nuts that meet the standards show n in Table 1.

2.2 Washers. Use washers that meet ASTM F436.

2.3 Threads . Provide anchor bolts with rolled or cut threads of UNC or 8UN series in accordance with

ASME B1.1. Anchor bolts 1 in. in diameter and smaller and 1- 3/4 in. in diameter and larger must have UNC series threads. If bolts have rolled threads, ensure the diameter of the unthreaded portion of bolts with rolled threads is at least the minimum pitch diameter and no greater than the maximum major diameter of the threads . If bolts have cut threads, ensure the diameter of the unthreaded portion is at least the minimum major diameter of the threads. Ensure all threads for bolts and nuts have Class 2 fit tolerances in accordance with ASME B1.1.

3.1 Fabrication . Welded splicing of anchor bolts is not permitted.

Provide an anchorage device with each anchor bolt consisting of a standard bolt head, a threaded bolt with nuts, or, if shown on the plans, a 90° bend. Make the inside- bend diameter approximately two times the anchor bolt diameter, but at no point along the bend greater than three times the bolt diameter. Hot bending is permissible provided the temperature does not exceed 1,100°F. When embedded templates are not specified and nuts are welded to the end of anchor bolts for anchorage, weld only on the nut face at the unstressed end of the bolt. Ensure no welding, arc, or other potential notch- producing effects occur in the stressed portion of the bolt. 693 Shipping of the anchor bolt cage in its assembled condition is not required.

3.2 Finish . Hot dip galvanize in accordance with Item 445, “Galvanizing.”

3.2.1 Anchor Bolts Embedded in Concrete . Galvanize the exposed end of the thread length plus a minimum of

6 in. unless otherwise shown on the plans.

3.2.2 Anchor Bolts Extending Through Concrete. Galvanize the complete length of the bolt.

3.2.3 Nuts . Galvanize exposed nuts. Galvanize the untapped blanks before cutting the threads.

3.2.4 Washers. Galvanize exposed washers.

3.3 Installation . Hold the anchor bolt and template assembly rigidly in position during concrete placement. Use

wood templates or other positive means to ensure correct positioning of anchor bolts not requiring steel templates. Positioning devices may be tack welded to the steel templates but not to any portion of the anchor bolts.

3.3.1 Anchor Bolt Thread Lubricant Coating. Coat anchor bolt threads before installing nuts using an electrically

conducting lubricant compound described in Section 449.3.3.2.1., “Definitions,” for traffic signal pole s, roadway illumination poles, high mast illumination poles, intelligent transportation system (ITS) poles, steel electrical service supports, and overhead sign support structures. Coat anchor bolt threads for other structures with pipe joint compound or beeswax. After installing nuts, repair galvanizing damage on bolts, nuts, and washers in accordance with Section 445.3. 4., “Repairs.”

3.3.2 Anchor Bolt Tightening Procedure . Tighten anchor bolts for traffic signal poles, shoe base and concrete

traffic barrier bas e roadway illumination poles, high mast illumination poles, ITS poles, steel electrical service supports, and overhead sign support structures in accordance with this Section. This procedure covers the tightening of nuts on a double- nut anchor bolt system using anchor bolts with 55- ksi or 105- ksi minimum yield strength and UNC or 8UN thread series to secure structures to drilled shaft foundations. 3.3.2.1. Definitions . The following definitions apply to the anchor bolt tightening procedure.  Double -Nut Anchor Bolt System . An anchor bolt with two nuts that sandwich the structure’s base plate. The bottom nut is positioned under the base plate to level, support, and provide the reaction for the force applied by tightening the top nut positioned above the base plate.  Electrically Conducting Lubricant . A compound commonly used in the electrical industry to coat threads of field- cut rigid metal conduit and suitable for exposure to weather.  Impact Tightening. The tightening of nuts using a box -end “slug” or “knocker” wrench and a sledgehammer. The wrench, matching the size of the nut to be tightened, is driven with the sledgehammer to rotate the nut.  Static Tightening. The tightening of nuts using a “spud” wrench and a pipe or extension handle. The wrench, matching the size of the nut to be tightened, may be turned using more than one worker to rotate the nut.  Snug- Tight . The condition when the nut is in full contact with the base plate. It may be assumed the full effort of a worker on a 12- in. wrench results in a snug- tight condition.  Turn- of-the-Nut Method. The tightening of top nuts to snug- tight condition, then establishing reference positions by marking one flat on each nut with a corresponding reference mark on the base plate at each bolt. Each nut is then turned to the prescribed rotation from the referenced snug- tight position. 3.3.2.2. Anchor Bolt Tightening. Perform the following procedure.  Coat the threads of the anchor bolts with electrically conducting lubricant.  Install the bottom nuts on the bolts, one on each bolt. 694  Level the top template (using it as a guide) by adjusting the bottom nuts so the template rests on each nut and the distance between the top of the concrete shaft and the bottom surface of the bottom nut is approximately 1/2 in.  Remove the template.  Coat the bearing surfaces of the bottom nuts and washers with electrically conducting lubricant.  Install bottom washers on bolts, one on each bolt.  Erect and plumb the structure as specified. Adjust the bottom nuts so each is bearing equally on the washer or base plate. The truss for cantilever overhead sign support structures and the mast arm for traffic signal poles must be removed during anchor bolt tightening.  With the plumbed structure supported by a crane, coat the bearing surfaces of the top nuts and washers with electrically conducting lubricant. Install one washer and one top nut on each bolt. Turn the top nuts onto the bolts so each is hand- tight against the washer or base plate.  Turn each bottom nut to a snug- tight condition using a wrench.  Verify the structure is still plumb and still supported by the crane. Begin turn- of-the-nut method by turning each top nut down to the same snug-tight condition. Prevent rotation of the bottom l eveling nut during all top nut tightening. Establish reference marks for turn- of-the-nut method once snug- tight condition is achieved, and then tighten the top nuts by turning each nut 1/12 turn (1/2 of a nut flat) past snug- tight using either static or impact tightening. Turn each top nut an additional 1/12 turn until each nut has been tightened 1/6 total turn past snug- tight.