Ground Anchors
- Design-Build
- Civil Construction
- Underground Utilities & Pipelines
- Paving
- TeleCommunications
- Retaining Walls, Waterfront, & Marine Construction
- Horizontal Directional Drilling
- Ground Anchors
- Tunneling, Horizontal Auger Boring, & Pipe Ramming
- Electrical Substations
- Heavy Demolition
- Concrete Construction
- Railroad Construction
- Deep Foundations
- Renewable Energy
- Bridges
Ground Anchors
Ground Anchors
Contact: Ben MacKinney: bmackinney@ecivt.com
ECI has extensive experience at installing rock and soil anchors for a variety of geotechnical applications including for excavation support systems, permanent retaining walls, slope stability, and suspension bridge anchorage.
Ground anchors typically involve a steel core with cement grout encapsulation for load transfer to the ground and for corrosion protection. Additional corrosion protection consisting of PVC or HDPE sleeves and special steel wall interface elements (trumpets) are often used on permanent anchors.
Most ground anchors are prestressed after the cement grout has cured to provide a clamping affect and also provides an opportunity to load test each anchor. These types of anchors are commonly called “tiebacks” and are typically load tested to 133% of their design load. Passive anchors with no initial stressing are typically called soil or rock nails. A representative portion of passive anchors are load tested at a prescribed frequency to a higher safety factor.
ECI’s specialty is installing hollow bar anchors with one of our TEI excavator drill attachments. Our fleet consists of both a HEM 550 which mounts on our John Deere 230 track excavator and our MMe260 which mounts on our John Deere 75 excavator. Both units are installed with a drifter which is a rotary-percussion top hole hammer. The drifter provides fast and efficient penetration into rock or soil conditions. The TEI drills also allow for the anchor to be installed from above the wall which is the only practical access on many projects.
Hollow bar anchors are used as the drill steel along with a sacrificial bit selected for the anticipated ground conditions. The hollow core allows grout, water, or air to be used to clear the cuttings to the surface, lubricate the tooling, and cool the tooling. Frequently grout is used for the entire drilling process which provides an enhanced soil bond and anchor capacity. The impact of the percussion drilling also improves the anchor capacity.
As with many geotechnical construction projects, the final design of the anchors is frequently provided by the contractor. ECI has two registered professional engineers with extensive design and construction experience.
