To accommodate future structural expansion, COPRA® Anchoring Coupler bolts were pre-installed in the lower structure during Phase 1. After completion of this phase, the structure was backfilled with soil. In the upcoming Phase 2, scheduled to take place several years later, the soil will be removed, and the upper structure will be connected to the pre-installed anchor bolts, enabling seamless extension of the utility tunnel.
Given the long-term underground installation, the coupler part was hot-dip galvanized (HDG) for corrosion protection. The interior was filled with vaseline grease and sealed with NPP caps to further prevent rust and ensure long-term durability.
This project is a result of close collaboration with the client, involving multiple rounds of technical discussions and product selection. It stands as a representative case demonstrating how COPRA® Anchoring Coupler bolts can effectively support long-term structural expansion in underground applications.

