Case Study: V3 Companies achieves precise underground tunnel profiling and bolt-hole layout with Trimble Connected Site solutions

V3 Companies - Customer Case Study

V3 Companies, an Illinois-based consulting firm, was hired to perform a topographic survey of a 488 m (1,600 ft) limestone tunnel at Mining International’s Joliet quarry. Although the tunnel was mostly straight, the assignment faced significant practical challenges: absolute darkness, restricted transport and workspace, high-platform work, heavy truck traffic that ruled out floor control, a diesel-only site that prohibited generators, and a need for precise ceiling profiles so a prefabricated conveyor could be hung with minimal disruption.

V3 used Trimble Connected Site solutions—linking a Trimble R8 GNSS receiver to a regional RTN and using a TSC2 controller with a Trimble VX spatial station—to extend control into the tunnel by mounting threaded rods and prisms in the walls. A Trimble GX 3D scanner with PointScape software (15 cm scan intervals) produced a combined point cloud (~45 MB), and a custom reversed-prism rod and boom truck were used to accurately set bolt holes for the conveyor. The approach delivered accurate ceiling profiles and bolt layouts for offsite prefabrication and efficient installation, with most difficulty coming from preparation rather than the scanning itself.

V3 Companies

Grant Van Bortel

Survey Technology Manager