GMA is relaunching Thorbolt adapted for different types of combination bolt. Adapter sleeves are currently available for M27, R27 and R32.
Common to these combination bolts is that injection takes place just as usual with a Thorbolt (from the bottom of the Thorbolt via a GX check valve) and then ventilation takes place from the top of the borehole via the inside of the combination bolt (through the hollow bolt). When injecting with a Thorbolt installed at the end of the combination bolt, an overpressure of 5-10 Bar beyond the actual water column can be created so that a dry zone is formed around the leaking borehole.
When using Thorbolt, the top expander on the current combination bolt can be replaced with the Thorbolt itself constitutes until its hardening of the injection compound has taken place (if the combination bolt being shortened at the top and the top expander removed). Of course the combination bolt can be shortened in the bottom end as well, using the same assembly system as for rebars presented here as well.
Adapter sleeves will be available in stainless steel to suit the selected Thorbolt model.
