In modern underground construction, rapid and reliable ground support is critical to project success. Whether tunneling through fractured rock or reinforcing mining stopes, engineers require anchoring solutions that provide immediate load-bearing capacity and long-term durability. SupAnchor, a leading self-drilling anchor system manufacturer, has addressed these challenges with the launch of the SupShell Expansion Rock Bolt System—a versatile drill-and-grout bolt designed for geotechnical reinforcement in the most demanding conditions.
The SupShell system is engineered to streamline installation while maximizing anchorage performance. Unlike traditional ground support methods that require separate drilling and anchoring steps, this hollow bar anchor integrates drilling, expansion, and grouting into a single pass. This not only accelerates advance cycles but also enhances safety, making it an ideal choice for infrastructure projects across Europe and the Americas.
At the heart of the SupShell system is a precision-engineered expansion shell that bites into the rock formation, delivering immediate mechanical anchorage upon installation. The bolt can then be post-grouted through its central hole, providing a full-column chemical bond that ensures long-term stability. This dual anchorage mechanism—mechanical expansion plus chemical grout—offers a robust solution for fractured ground where conventional bolts might fail.
Key technical data highlight the system’s adaptability. The SupShell is available in five models—R25, R28, and three R32 variants—each optimized for specific borehole conditions. All models use CK45 steel and feature ISO 10208 thread profiles, ensuring compatibility with standard drilling equipment. The table below summarizes the dimensional specifications:
| Model | Specification | Outside Diameter (mm) | Drilling Hole Diameter (mm) | Length (mm) | Weight (kg/m) |
|---|---|---|---|---|---|
| R25 | R25/EX36 | 36 | Φ40-Φ42 | 132 | 0.62 |
| R28 | R28/EX40 | 40 | Φ44-Φ46 | 136 | 0.84 |
| R32 | R32/EX44 | 44 | Φ48-Φ50 | 135 | 0.82 |
| R32 | R32/EX46 | 46 | Φ50-Φ52 | 176 | 1.2 |
| R32 | R32/EX48 | 48 | Φ52-Φ54 | 165 | 1.45 |
Installation is straightforward. A plastic sealing element at the collar prevents grout or resin leakage, ensuring complete borehole filling. This feature, combined with the expansion shell’s immediate grip, allows for pre-grouting or post-grouting depending on ground conditions. The result is a self-drilling anchor bolt that significantly reduces installation time and labor costs while improving fortification cycles.
The SupShell system is designed to overcome common site challenges. The integrated injection system allows grout to enter through the center hole of the bolt from the bottom, ensuring complete encapsulation of the anchor. A high-strength plastic sealing element prevents grout leakage, a common cause of anchor failure in fragmented rock. This design aligns with the highest quality benchmarks, including the EN 10083 standard for steel bars, guaranteeing reliable performance even in high-stress environments.
Key advantages include:
The SupShell Expansion Rock Bolt System excels in a wide range of geotechnical reinforcement applications. In tunneling, it provides immediate face stabilization in broken rock, enabling safer and faster excavation. For mining, its dual anchorage withstands dynamic loads and blasting vibrations, reducing the risk of roof falls. The system also serves as a drill-and-grout bolt for soil nail systems in slope stabilization, where the hollow bar allows for efficient grout delivery without separate casing. For instance, on major European infrastructure projects like the Brenner Base Tunnel, where squeezing ground demanded immediate support, the SupShell’s rapid installation and reliable dual anchorage helped maintain safety and schedule.
Its adaptability to varying hole diameters—from 40 mm to 54 mm—and lengths up to 176 mm makes it a versatile choice for contractors. By combining drilling, anchoring, and grouting into one operation, the SupShell system minimizes equipment downtime and maximizes advance cycles. This has direct economic benefits: fewer man-hours, reduced consumables, and faster project delivery. For large-scale infrastructure, such as metro tunnels or high-speed rail cuttings, these efficiencies translate into millions in savings. As a ground anchor bolt factory with a global footprint, SupAnchor serves projects from Scandinavian hard rock tunnels to soft ground metro stations in the Americas.
SupAnchor’s position as a leading soil nail system manufacturer and self-drilling anchor system provider is built on continuous R&D. The SupShell embodies this philosophy with its optimized expansion shell geometry and high-strength CK45 steel that resists deformation under high torque. By combining mechanical and chemical anchorage, the bolt meets the dual demands of immediate safety and long-term durability—a challenge that has long plagued mines and tunnels.
With ISO-certified manufacturing and a growing portfolio of successful installations worldwide, SupAnchor remains dedicated to advancing geotechnical reinforcement technology. The SupShell Expansion Rock Bolt System is the latest example of how professional engineering, innovative design, and collaborative project support can raise the bar for underground construction.
For more information on SupAnchor’s complete range of self-drilling anchor bolts and ground engineering solutions, visit www.supanchor.com.
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