Charteris BluGeo K60 GRP

Grouting Services in conjunction with Bluey Technologies undertook a trial installation of the BluGeo Powerthread K60-25 GRP bars for Christchurch City Council. The purpose of the trial was to verify the suitability of the GRP bars for anchoring works and a suitable site was selected in Charteris Bay. A scheme was developed that involved the installation and testing of 5No anchors with lengths varying from 6m to 15m. McMillan Drilling provided local specialist drilling services. Fulton Hogan provided traffic management and site preparation services.

The proving trial anchors were specified as BuGeo Powerthread K60-25 grade 1000 GRP bar with a UTS 350kN in a 150mm diameter hole. Bond lengths ranged from 5.9m to 14.75m and free lengths ranged from 0.5m to with a 2.95m. A distal nut was also required to be fitted to each anchor.

The trial anchors were fabricated into the required configuration on site with the following designations:

• Anchor 1 : 5.9m length
• Anchor 2 : 8.85m length including 2.95m free (debonded) length
• Anchor 3 : 11.8m length
• Anchor 4 : 11.8m length including 2.95m free (debonded) length
• Anchor 5 : 14.75m length

All anchors were tested to 180kN without rupturing the grout-to-ground bond.