DUCKBILL® ENGINEERED EARTH ANCHOR SYSTEMS INSTALLATION GUIDELINES Introduction The Duckbill Principle Holding Capacity Installations Driving the Anchor Mechanical Anchor Locking Hand Anchor Locking Jacks Hydraulic Jack Soils Soft Soils Hard Soils & Rock 11 6430 East 49th Drive Commerce City, Co 80022 (USA) 1-800-325-5360 TEL: 303-286-8955 FAX: 303-287-3866 www.duckbill.com Sales@duckbill.
INTRODUCTION This guide serves to aid suppliers and installers of DUCKBILL® Earth Anchors about installation methods and techniques. DUCKBILL is offered in 4 Aluminum alloy anchor models and 3 galvanized ductile iron anchor models (for very hard / rocky soils). The anchors range in holding capacities in normal soil from 300 to 5000 Ibs. (135 kg to 2250 kg) The DUCKBILL Earth Anchor has been developed to function in the total range of soils.
SOILS Class Description Probe Value 1 Solid Bedrock Over 600 in./lbs 2 Dense Clay; Compact Gravel Dense Fine Sand; Laminated Rock; Slate; Schist; Sand Stone 500-600 in./lbs 3 Shale; Broken Bedrock; Hardpan; Compact Gravel Clay Mixtures 400-500 in./lbs 4 Gravel; Compact Gravel and Sand; Claypen 300-400 in./lbs 5 Medium-Firm Clay; Loose Standarad Gravel; Compact Coarse Sand 200-300 in./lbs 6 Medium-Firm Clay; Loose Coarse Sand; Clayey Silt; Compact Fine Sand 100-200 in.
INSTALLATION DRIVING THE ANCHOR 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. The DUCKBILL® can be driven at any angle. In guy applications the angle of the installation should closely match the angle of the guy line. Start by inserting the drive steel into the anchor body. Use a sledgehammer, fence post driver or a power driven jack-hammer to drive the anchor to the proper depth.
HAND ANCHOR LOCKING JACKS 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. The DUCKBILL “hand hook” is also available. HYDRAULIC JACK The LL-2 Anchor Locker is designed to load lock and test the full line of DUCKBILL Anchors.
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 guy lines, also not desired.
