DUCKBILL ANCHORS

RECOMMENDED INSTALLATION GUIDELINES

ANCHORS

The anchors are rated in an average soil conditions. Higher capacities can be expected in harder soils and lower capacities in softer soils. The rating is mainly useful as a reference for anchor selection. Proof-loading is the only way to insure the exact capacity of each installation. This is true for all anchors on the market today.

INSTALLATION
The first step in any installation is to select the proper anchor for the job. Keep in mind the maximum load expected and add a reasonable safety factor.

DRIVING THE ANCHOR
The DUCKBILL® can be driven to almost any depth at any angle. In guy applications the angle of the installation should closely match the angle of the guyline. Start by inserting the drive steel into the anchor body. Use a sledge hammer, fence post driver or a power driven jack-hammer to drive the anchor to the proper depth. Fill hole made by anchor with soil. This will not allow water to seep down to the anchor, causing wedge out or hardening soil.

LOCKING THE ANCHOR
After the anchor has been driven to depth, the drive steel is retracted from the anchor. Pull back on the anchor cable to toggle the anchor into the
perpendicular (anchor-locked) position. In average soils a rule of thumb is that the length of pull should equate to the length of the anchor. For example: Model 88 anchor body measures 6" inches. A pull of 5-6" will rotate the anchor into a completely perpendicular position.
Several methods are used to anchor lock the anchors.

LOCKING BY HAND The smaller DUCKBILL models may be locked by hand. Insert the drive steel through the cable loop or wrap the cable around the drive steel to fashion a "T" handle. Pull on the drive steel to anchor-lock the anchor. A fulcrum is also very useful in locking anchors by hand. A custom made Hook or Lever can also be used for Locking Duckbills.

JACKS Ordinary automotive bumper jacks or handyman jacks work well on medium and larger sized anchors. By adding legs or a custom base to the jack angled pulls are achieved with greater ease.

COME-ALONGS AND FENCE STRETCHERS These tools work very well providing that there is a substantial counter anchor nearby. A truck bumper for example. In general the object that is to be guyed is not acceptable as the counter anchor. It will deflect prior to the anchor reaching full anchor-lock position.

HOLLOW HYDRAULIC CYLINDERS
Although a specialized piece of equipment, a hollow hydraulic cylinder is a very good tool for someone who will install many anchors on a regular basis. Being small and lightweight they are ideal for horizontal installations. A hydraulic pressure gauge often accompanies this set-up so that every installation may be checked for capacity. (proof loading)

NO MATTER WHAT METHOD IS USED, IT IS CRITICAL THAT THE ANCHOR BE PROPERLY LOCKED BEFORE TYING OFF THE OBJECT TO BE ANCHORED.

An anchor not properly locked prior to attaching will result in significant pull out before the anchor self locks. Obviously this is not desired.
Failure to install and lock the anchor at the correct angle will result in the anchor cable cutting through the soil until the angles equalize. This will cause slack in guylines, also not desired.

SPECIAL SOILS CONSIDERATIONS

SOFT SOILS
In areas where the soil proves to be softer than normal, steps should be taken to assure the capacity of the anchor. Proof-loading is especially useful in soft soils. Guesswork as to the capacity is eliminated. The installer will know immediately if the anchor point is adequate or if further steps are necessary.

Backfilling and tamping the hole behind the anchor will yield somewhat higher capacity in most soft soils. Fill and tamp the hole in 3" lifts prior to anchor locking the anchor. Another option is to drive the anchor deeper in an effort to penetrate a harder layer of soil. Larger anchors may need to be placed to achieve the required load. As a last resort a number of anchors may be placed in a cluster and bridled together to form one point.

HARD SOILS AND ROCK
If excessive resistance to driving occurs it may be necessary to drill a hole for anchor placement. If the anchor stops moving and is subjected to excessive pounding (especially from power equipment) metal fatigue can occur and the anchor body can fracture.

CLEARANCE HOLE DIAMETERS AND
HARD SOIL PILOT HOLE DIAMETERS
FOR DUCKBILL® EARTH ANCHORS

INSTALLATION OF DUCKBILL ANCHORS IN HARD SOILS CAN BE GREATLY HELPED BY THE USE OF A PILOT HOLE. TYPICALLY, THE PILOT HOLE HAS NO SIGNIFICANT AFFECT ON THE HOLDING POWER OF THE ANCHOR. THERE ARE MANY ACCEPTABLE METHODS OF DRILLING PILOT HOLES AND MANY MANUFACTURES OF EQUIPMENT TO DO SO. RECOMMENDED HARD SOIL PILOT HOLE DIAMETERS AND CLEARANCE HOLE DIAMTERS ARE CHARTED BELOW.

The DUCKBILL® anchor may be placed in a pre-drilled hole in hard dirt or rocky material, and achieve very good results. Hand augers and gasoline or hydraulic powered earth drills can be used to form the hole. A PIONJAR 120 gasoline powered breaker/drill is very useful due to the fact that it performs both drilling and driving operations.