The system is designed for efficient installation and reliable performance in difficult or unstable ground conditions.

Manufactured with a minimum 85-micron hot-dip galvanised coating, the system provides durable corrosion protection and a cost-effective solution for both temporary and permanent works in civil engineering, slope stabilisation, and foundation applications.

System Description

The galvanised hollow bar anchor system is a fully threaded, self-drilling solution that combines drilling, grouting, and anchoring into a single operation. The hollow bar acts as both the drill rod and grout conduit, enabling installation without casing, even in loose or collapsing ground.

Bars are produced with a cold-rolled ISO-standard left-hand rope thread, ensuring compatibility with commonly used drilling rigs, couplers, and accessories across UK and European sites.

Available in standard stock lengths or cut to project-specific requirements.

Key Applications of Galvanised Steel SDA Systems

Slope stabilisation and soil nailing
Tunnel face, crown and sidewall support
Spiling / forepoling ahead of tunnel excavations
Temporary and semi-permanent retaining walls
Excavation and basement support works
Micropiles and foundation underpinning
Ground consolidation and pressure grouting
Rock bolting for civil and mining applications
Portal stabilisation and temporary ground support

Performance and Components

The system is available in multiple bar diameters to suit varying load requirements and ground conditions. Optimised bar geometry and precision-rolled threads provide effective load transfer throughout the anchorage.

Compatible components and accessories include:

High-strength couplers designed to transfer full bar capacity
Full and domed nuts for flat or misaligned bearing plates
Flat and domed bearing plates
Centralisers for consistent grout cover
Adaptor sleeves
Drill bits for soil, gravel, and rock conditions

Corrosion Protection

While stainless steel hollow bar systems are recommended for aggressive environments, galvanised hollow bar anchors offer an effective balance of strength, durability, and cost efficiency for typical UK soil and groundwater conditions.

The 85-micron galvanised coating provides reliable service life for a wide range of ground engineering applications.

Accessories (all dimensions in mm)

Product	Size	Outer Dia.	Length	Weight
Adaptor Sleeve	25/32	32	50	0.10
Centraliser	32	72	30	0.27
Centraliser	38	78	30	0.28

Product	Nominal Dia.	Stock Length*	Nom. Outer Dia.	Internal Dia.	Ultimate Tension Capacity (kN)	Yield Tension Capacity (kN)	A Elongation (%)	Agt (%)	Weight (kg/m)
R25	25	1500 & 3000	24.7	14	200	150	≥8%	≥5%	2.35
R32N	32	1500 & 3000	31.3	18.5	280	230	≥8%	≥5%	2.95
R32S	32	1500 & 3000	31.3	15	360	280	≥8%	≥5%	3.50
R32S1	32	1500 & 3000	31.3	12	405	320	≥8%	≥5%	4.00
R38N	38	1500 & 3000	38	19	500	400	≥8%	≥5%	4.95
R38S	38	1500 & 3000	38	15	550	450	≥8%	≥5%	5.90

Fittings (all dimensions in mm)

Product	Size	Outer Dimension	Length	Weight (kg)
Coupler	25	Ø36	150	0.66
Coupler	32	Ø42	190	1.01
Coupler	38	Ø51	220	1.68
Full Nut	25	41 (A/F)	40	0.31
Full Nut	32	46 (A/F)	45	0.37
Full Nut	38	50 (A/F)	60	0.47
Domed Nut	25	41 (A/F)	40.5	0.31
Domed Nut	32	46 (A/F)	45	0.38
Domed Nut	38	52 (A/F)	60	0.61
Wedge Boss	25-38	122	70	1.00
Product	Size	Dimensions	Thickness	Weight (kg)
Domed Plate	25	200 x 200	10	2.94
Domed Plate	32	200 x 200	12	3.52
Domed Plate	38	200 x 200	12	3.6

Drill Bits (all dimensions in mm)

Size	Type	Outer Dia.	Description	Typical Applications
SSR32/51	EXX	51	Cross Bit with Tungsten Carbide Inserts	Softer sedimentary rocks such as marls, mudstones, siltstone
SSR32/76	EXX	76	Cross Bit with Tungsten Carbide Inserts	Softer sedimentary rocks such as marls, mudstones, siltstone
SSR38/76	EXX	76	Cross Bit with Tungsten Carbide Inserts	Softer sedimentary rocks such as marls, mudstones, siltstone
SSR38/100	EXX	100	Cross Bit with Tungsten Carbide Inserts	Softer sedimentary rocks such as marls, mudstones, siltstone
SSR38/130	EXX	130	Cross Bit with Tungsten Carbide Inserts	Softer sedimentary rocks such as marls, mudstones, siltstone
SSR32/51	ES-F	51	Hardened Steel Button Bit	Gravel, soft rock
SSR32/76	ES-F	76	Hardened Steel Button Bit	Gravel, soft rock
SSR38/76	ES-F	76	Hardened Steel Button Bit	Gravel, soft rock
SSR38/90	ES-F	90	Hardened Steel Button Bit	Gravel, soft rock
SSR38/115	ES-F	115	Hardened Steel Button Bit	Gravel, soft rock
SSR32/51	ESS-F	51	Hardened Steel Button Bit with Tungsten Carbide inserts	Weathered rock, stone walls, rubble
SSR32/76	ESS-F	76	Hardened Steel Button Bit with Tungsten Carbide inserts	Weathered rock, stone walls, rubble
SSR38/76	ESS-F	76	Hardened Steel Button Bit with Tungsten Carbide inserts	Weathered rock, stone walls, rubble
SSR38/90	ESS-F	90	Hardened Steel Button Bit with Tungsten Carbide inserts	Weathered rock, stone walls, rubble
SSR38/115	ESS-F	115	Hardened Steel Button Bit with Tungsten Carbide inserts	Weathered rock, stone walls, rubble