Rock and soil anchors offer an economical solution to temporary or permanent stability or support problems. Designed to withstand lateral and uplift forces, these structural members are typically used with temporary, deep excavation support systems, as a part of permanent retaining walls, for dam stabilization or to resist wind-produced uplift
forces.
Ground Anchors are load transfer systems consisting of . . .
Anchor in stable ground
Long tendon
Connection to structure
Ground Anchor Applications
Lateral support of walls
Resistance of hydraulic uplift
Stabilization of landslides
Resistance to overturning
Ground Anchor Design Steps
1. Establish geotechnical conditions
2. Establish loading diagram and construction sequence
3. Develop trial anchor capacity
4. Develop anchor zone design
5. Check overall stability
6. Field test anchors
Anchor Quality Control Items
Monitor grout quantity and pressure
Performance test at selected anchors
Proof test all anchors (QA)
Evaluate tendon elongation and creep (QA)
Proposed ASTM Test Criteria
Performance Test
133% of design load (cyclic)
Load held at 133% for 10 minutes
If creep readings are greater than .04 inches between the 1-minute and 10-minute readings, load held for an additional 50 minutes
Proof Test
133% of design load
Load held for 5 minutes
Creep between 1-minute and 5-minute reading with predetermined limits set by performance test
Current criteria recommendations for prestressed rock and soil anchors, Post-Tensioning Institute, Phoenix, Arizona
Corrosion Protection at Connections Exposure to the elements requires anchors to be properly protected. Measures taken might include:
Trumpets
Secondary grouting
Protective anchor caps, grouted or filled with grease
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