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DCP-Rock Bolt

The Rock Bolt for permanent Slope Stabilizations, Tunnels and Caverns (with angle compensation)
High tensile and mild steel – DYWIDAG THREADBAR ^®

Superior performance — On-site assembly to any length
Double Corrosion Protection (DCP) consisting of corrugated plastic sheathing and cement grout.
Stressable with hydraulic jack immediately after installation. Hydraulic jack sitting on shoulder of hemispherical seat.
Direct load transfer from anchor head to expansion shell. Compressed rock mass between expansion shell and anchor head.
Up to 30° angle compensation at anchor head.
One stage field grouting: Grout flows between tensioned bolt and sheathing and then between sheathing and bore hole wall. Anchors can be inclined upwards or downwards.
Use of thixotropic grouts recommended.
After grouting, full bolt length will bond to the rock.
Protection of hex nut by screw-on steel cap.
All exposed parts are galvanized.
Recommended injection rate of cement grout: 10 litre/minute.
Dry pack and vent tube may be required.

Stressing Set Up

Anchor head with solid wedge plate and hemispherical seat (15°+12° angle compensation)

: Anchor head with domed plate and hemispherical seat (10°+20° angle compensation)

THREADBAR ^®	Steel Area	Yield Load	Ultimate Load	Grade	Anchor Plate
				f_y / f_u	Flat Plate	Domed Plate	Wedge Plate
	[mm²]	[kN] / [kips]	[kN] / [kips]	[MPa]	[mm]	[mm]	[mm]
25M / #8	510	263 / 59.3	351 / 79	517 / 690	200x200x20	200x200x12.5	185x185x15° Hole 80Ø
20Ø	314	282 / 63.4	345 / 77.5	900 / 1,100	200x200x20	200x200x12.5	same
26.5 / 1"	551	456 / 102	570 / 127.5	830 / 1,035	200x200x25	200x200x12.5	same
Possible angle compensation					20°	30°	27°
Expansion Shell	max. load 200 kN / 45 kips subject to rock conditions and borehole diameter				for bore holes Ø 60-65 mm length over all: 150 mm max. Ø before expansion: 58 mm

Subject to modification.