As infrastructure projects grow in scale and complexity, engineers face increasing demands for reliable, high-capacity ground support systems. SupAnchor, Asia's leading manufacturer and exporter of self-drilling anchors, has responded with its new Grade 75 self-drilling hollow anchor. This innovative product expands the company's extensive product line, offering elevated tensile and yield strengths to tackle heavy-load applications in deep foundations, tunnel excavation, and large-scale slope stabilization. The Grade 75 anchor embodies the "professional, innovative, collaborative" ethos that has made SupAnchor a trusted partner in global geotechnical engineering.
At the core of the Grade 75 anchor is the proven 3-in-1 principle that has made SupAnchor's self-drilling anchor system a staple in modern geotechnical engineering. Each hollow bar anchor functions simultaneously as a sacrificial drill rod, an injection tube for grouting, and a permanent reinforcing member. This integration eliminates the need for separate casing, drastically reducing installation time and equipment complexity, particularly in unconsolidated or cohesive soils where traditional step-by-step drilling is inefficient and risky.
What sets the Grade 75 variant apart is its high-strength steel composition, engineered to deliver significantly higher ultimate and yield loads compared to standard carbon steel grades. For example, an R32 model in this series achieves an ultimate load of ≥380–420 kN and a yield load of ≥300–340 kN—substantially higher than the standard R32/320 model (≥320 kN ultimate). This strength advantage ensures the anchor can withstand heavy tensile and shear forces, making it suitable for high-load scenarios such as deep foundation reinforcement, heavy-duty tunnel support, or large-scale slope stabilization where standard anchors may not meet force requirements.
The anchor's ribbed hollow bar design, with a relative rib area (fR) of 0.21–0.33 and 45° angled ribs, maximizes bonding with grouting materials while reducing splitting forces on surrounding soil or rock. At maximum load, crack widths remain below 0.1 mm, ensuring structural stability even under extreme conditions.
Although official datasheets are forthcoming, SupAnchor's systematic product logic allows us to infer key parameters for common diameters within the Grade 75 series. The table below compares expected values for R32 and R38 models, which are available in lengths from 2 to 8 meters (x2 to x8 multiples). These self-drilling anchor bolts feature ISO 10208-compliant threads (left or right) for quick on-site connection and compatibility with standard nuts, couplers, and plates.
| Parameter | R32/75 (Inferred) | R38/75 (Inferred) |
|---|---|---|
| Outer Diameter (mm) | 32 | 38 |
| Inner Diameter (mm) | 18–20 | 19–21 |
| Cross Sectional Area (mm²) | 400–450 | 600–650 |
| Ultimate Load (kN) | ≥380–420 | ≥550–600 |
| Yield Load (kN) | ≥300–340 | ≥440–480 |
| Weight (kg/m) | 3.2–3.6 | 4.7–5.1 |
| Thread Type | ISO 10208 R32 | ISO 10208 R38 |
| Elongation (%) | A100mm ≥6% / Agt ≥5% | A100mm ≥6% / Agt ≥5% |
| Anchor Nut Size | SW46/L65 | SW55/L70 |
| Coupler Size | D42/L190 | D50/L210 |
These drill-and-grout bolts offer up to a 30% increase in load capacity compared to standard models, directly addressing the needs of heavy infrastructure. The high-strength steel ensures minimal deformation under extreme loads, while the elongation properties (A100mm ≥6%, Agt ≥5%) provide ductility that prevents brittle failure—a critical safety feature for permanent support in nuclear auxiliary structures or high-pressure pipeline corridors.
Despite its focus on mechanical strength, the Grade 75 hollow bar anchor does not compromise on durability. It is fully compatible with SupAnchor's anti-corrosion treatments, including hot-dip galvanizing and SupCoating, enabling deployment in moderately corrosive environments such as inland heavy-duty infrastructure with damp soil. The standardized thread design (R thread per ISO 10208 or T thread per international standards) ensures quick coupling with accessories, reducing labor intensity and avoiding construction delays. As a ground anchor bolt factory committed to efficiency, SupAnchor’s integrated system allows the same crew and equipment to handle drilling, grouting, and tensioning in a single pass.
The ribbed profile, combined with the 45° angled ribs, enhances grout adhesion and transfers loads evenly into the surrounding ground, minimizing stress concentrations. This geotechnical reinforcement system is equally adept in soft soils, fractured rock, and cohesive substrates, making it a versatile choice for unpredictable site conditions.
The Grade 75 self-drilling anchor bolt is poised to become a benchmark in geotechnical reinforcement systems for projects that demand exceptional load-bearing capacity. Typical application scenarios include:
In each case, the Grade 75 anchor’s superior load thresholds provide engineers with a wider safety margin, reducing the number of anchors required and accelerating construction schedules. As a soil nail system manufacturer, SupAnchor ensures that these anchors integrate seamlessly with standard plates and nuts, facilitating adoption without specialized training.
With over a decade of focused R&D, SupAnchor has solidified its position as a global leader in self-drilling anchor systems. The company’s adherence to international standards like ISO 9001, ISO 14001, and OHSAS 18001 underpins every product, including the Grade 75 hollow bar anchor. Its manufacturing facilities in Asia serve projects across Europe, the Americas, and Oceania, where the demand for reliable ground anchor bolt factory solutions continues to grow.
“The Grade 75 series is more than a product extension—it’s a strategic response to feedback from our geotechnical partners,” says a SupAnchor spokesperson. “We recognized that megaprojects and critical infrastructure require anchors that can handle higher stresses without sacrificing the efficiency of our 3-in-1 design. This innovation reinforces our commitment to professional, collaborative engineering.”
SupAnchor’s portfolio now spans four main variants: standard R thread, T thread, stainless steel, and the high-strength Grade 75. This breadth allows engineers to specify the ideal geotechnical reinforcement system for any loading and corrosion condition. By continuously refining rib geometry, thread standards, and steel grades, SupAnchor ensures that its hollow bar anchors remain at the forefront of drill-and-grout technology.
As infrastructure investment surges globally, the Grade 75 self-drilling anchor bolt is set to become a go-to solution for projects that cannot compromise on safety or performance. For more information, visit SupAnchor’s official website or contact their technical support team to discuss custom diameters and lengths tailored to specific site requirements.
SupAnchor's self drilling anchor system deployed in a major Swiss Alps rail project to stabilize a steep slope amidst fractured rock and high groundwater. The integrated drill-and-grout solution enhances safety and efficiency.
SupAnchor expands its self-drilling anchor system with Grade 75 high-strength hollow bar anchors, designed for heavy-duty infrastructure and challenging ground conditions.
SupAnchor introduces a corrosion-free GFRP dowel bar with 100-year service life, high strength, and superior load transfer, ideal for jointed pavements and EMI-sensitive areas.
SupAnchor’s self drilling anchor system proves vital in a European metro expansion, overcoming fractured rock and groundwater to ensure safe, rapid tunneling and slope stabilization.
SupAnchor's new stainless steel self-drilling hollow anchor combats corrosion in marine, chemical, and humid projects. The R32SS/15 model delivers 405 kN ultimate load, long service life, and compatibility with standard accessories.
