DYWIDAG GFRP Anchor System
Cuttable anchor for use in urban applications or adjacent to tunnels.
- Excavation Support
The DYWIDAG GFRP Bar Anchor system comprises Glass Fibre Reinforced Polymer threadbars, typically arranged as a multi-bar system to form the anchor tendon. Because the anchors do not require de-stressing before cutting, they can be easily cut with simple digging equipment such as an excavator bucket or road header. This means they are often used in applications where subsequent works such as piling or tunneling are required within the anchoring zone once the anchors are redundant.
GFRP is very efficient in tension but has poor compressive strength and shear characteristics. Therefore, coupling and nut terminations have significant lower capacities than the bar. GFRP anchor free lengths are typically single section, with the option of a steel coupler at the free length / bonded length intersection. Free length sections can be supplied as a single 22-meter section, as couplers within the free length are not recommended.
For termination and stressing, long-length steel nuts are typically used. The GFRP Bar System is supplied with standard free length details (debond tubes) as used on conventional ground anchors, therefore stressing and lock-off operations are as per standard anchors. Stressing of GFRP multi-bar systems requires an open stool and multiple back nuts at the top of the jack.
Cuttable anchors for when piling or tunnelling works will take place nearby, saving time and labor
Easily cut with simple digging equipment, such as an excavator bucket or road header, which avoids extra operations
Supplied with standard free length details (debond tubes) as used on conventional ground anchors, therefore stressing and lock-off operations are as per standard anchors.
Flexible installation lengths with free length sections of up to 22 meters, and steel couplers available for use at the free length/bonded length intersection
High capacities of up to 1280 kN using 3-bar or 4-bar systems
Stressing of GFRP multi-bar systems requires an open stool and multiple back nuts at the top of the jack
Bearing plates with angle compensation
Borehole spacers : lantern
Tremie tubes for borehole grouting (bottom up)
Post-grouting tubes complete with TAM (tube à manchette) valves for bond stress enhancement
Spreader beams for loading and unloading