THREADBAR ® Anchors
Corrosion Protection
DYWIDAG THREADBAR ® Anchors with Single Corrosion Protection SCP
Single corrosion protected anchors are used for temporary anchors and sometimes for permanent anchors in non-aggressive rock or soil. A Polyethylene sheathing covers the free stressing length. The THREADBAR ® is coated with a corrosion inhibitor before the polyethylene sheathing is installed. The bond length is covered with cement grout.
| Basic Type | Variations | Grouting | |||
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| Angle compensating bearing and wedge washer | Concrete or steel support for stressing anchorage | ||||
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| Coupler for removable anchor | Fixed coupler for difficult installation conditions | ||||
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| Elastic centralizer for cased drill holes | Threaded centralizer for drill holes in rock | Flush tube for soil anchors | Post-grouting system for cohesive soil | Grout tube for rock anchors | |
DYWIDAG THREADBAR ® Anchors with Double Corrosion Protection
Double corrosion protected anchors are recommended for anchors with a long service life and for an environment where aggressive materials or stray electrical currents are expected.
A corrugated high strength PVC sheathing with plastic end caps is installed over the full length of the anchor. The annular space between THREADBAR ® and PVC is fully grouted before the anchor is installed. To accommodate the bar elongation during stressing, a short length of THREADBAR ® is left free of the corrugated sheathing under the stressing anchorage. A steel pipe welded to the anchor plate and filled with corrosion preventive compound or grout protects the free end of the bar against corrosion.
A smooth plastic sheathing is installed over the corrugated sheathing in the stressing length. This allows the tendon to elongate during stressing.
The corrugated plastic sheathing acts as a protective membrane preventing intrusion of any corrosive substances. The cement grout around the THREADBAR ® provides corrosion protection by embedding the bar in an alkaline environment. The THREADBAR ® deformations minimize the width and control the distribution of any cracks that develop in the free stressing length, fully maintaining the protective action of the grout cover.
A protective plastic or steel cap filled with a corrosion preventive compound is installed over the anchor nut after stressing, completing the full encapsulation of the anchor tendon. The cap is removable for checking and/or adjusting the force level in the anchor tendon at any time in the future.
| Basic Type | Variations | Grouting | |||
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| Angle compensating bearing and wedge washer | Concrete or steel support for stressing anchorage | ||||
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| Splice in free stressing length or bond length | Packer | ||||
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| Elastic centralizer for cased drill holes | Threaded centralizer for drill holes in rock | Flush tube for soil anchors | Post-grouting system for cohesive soil | Grout tube for rock anchors | |