Polyester Resin Grout

Applications

DSI Duo Speed Resin Capsules are designed specifically for use in the mining industry.

DSI Duo Speed Resin Capsules are flexible enough to use in conjunction wilh steel roof bolt, cable bolts and fiberglass bolts in the roof or sidewalls.

DSI Duo Speed Resin Capsules can be installed with most inslallation equipment from hand-held pneumatic drills to high speed hydraulic bolting machines.

Function

Polyester resin acts as a load transfer mechanism when used in conjunction with roof support members, transferring stress from the rock to the bolt or the bolt to the rock.

Stress in Ihe surrounding rock can be transferred to the roof bolt, stabilising the rock. Jointed or fractured blocks or layers of rock can be keyed together by single or multiple roof bolts allowing weaker layers or blocks to transfer stress loads to stronger layers or blocks.

When used with pre-tensioned supports, the tension Ioad from the support member can be transferred to the rock. providing increased stabilisation.

Description

The active Ingredients in DSI Duo Speed Resin Capsules are a thixotropic polyester resin mastic and an organic peroxide catalyst.

The resin end and catalyst are enclosed and sepereted from each other in a polyester firm capsule for convenient placement in a drilled hole. When a steeI or fiberglass roof bolt is introduced into the drilled hole and spun up under load, the polyester capsule ruptures mixing the resin and calalyst as it is forced into the annular gap.

During the mixing of catalyst and resin an exothermic reaction occurs transforming the mixture into a high strength solid state.

Strength of Polyester Resin Grout

The following is a laboratory environment short Imbedment test in whichl steel roof supports are imbedded in a block of limestone rock with DOSI polyester resin grout. The test parameters are as follows:

• Bolt
• 20.4 mm core diameter rebar
• Yield Strength - 520 MPa minimum
• Block
• Compressive Strength - 27,5 MPa minimum
• Drilling Method - rotary wet drilling
• Hole diameter - 26,4 mm
• Annular gap - 6 mm
• Resin
• Embedment Length - 300 mm
• Resin cure Time - 24 hours

Results

Under these conditions, 300 mm annular columns of polyester resin can sustain loads of 100 kN with an average deflection of 3mm.

Load transfer rates can vary greatly among various types of rock, and in situ tests should atways be performed in the rock environment for which the resin and roof support member is intended.

Technical Support

DSI - Australia is dedicated to offering complete technical and field support service. Contact your DSI representalive or your locel distributer for further details.

Properties - Set Time

Typical set times at 25C are as follows:

The hold time stated above are the minimum times allowed after the spin time is completed and before bolt tensioning is attempted. In many cases the hold lime can be greater than the minimum stated time.

Hold limes are an indication only. they may vary with ambient temperature, bolt / hole geometry. anchoring material. and equipment speed (rpm) and virgin rock temperature.

Each area within the mine should be evaluated to determine the best installation parameters.

Further detailed information can be obtained by contacling you local DSI representative or your local distributor.

Temperature Effect on Resin Gel Time

Anchor Strength vs Time

Following is a typical strength development curve vs time .
Parameters

• Bolt
• 20.4 mm core diameter rebar
• Yield Strength - 520 MPa minimum
• Block
• Compressive Strength - 27,5 MPa minimum
• Drilling Method - rotary wet drilling
• Hole diameter - 26,4 mm
• Annular gap - 6 mm
• Resin
• Embedment Length - 300 mm

Installation Instructions

Good bolting practices must be continuously followed to insure that quality, high strength installations are achieved, Following the guidances below and the instructions on the box are essential.

1. Drill the hole using the pre-determined bit diameter for the bolt to be installed, Water or air flush / vacuum is essential to remove the majority of dust and loose particles. Typical bolt diameter used in coal mining is 22mm, Typical hole diameter used in coal mining is 27-28mm.
2. Drill the hole to correct length for the bolt The ideal hole length for tension rebar applications is 50-100mm shorter than the bolt.
3. Select the proper resin capsule that has been specified for the job.
4. Check the expiration date on the box. Do not use resin that has expired.
5. If separate fast and slow capsules are to be useed in tension applications, it is essential that the fast resin be installed first followed by the slow.
6. Insure that the capsules are installed to the top of the drilled hole using the bolt or other insertion device. Failure can result in loss of encapsulation and air gaps in the resin anchor. If the capsule does not reach the top of the hole, the problem must be investigated.
7. Connect the bolt to the spinning dolly / spanner.
8. Insert the bolt using constant feed and maximum spin until the bearing plate contacts the roof. Continue to spin for an additional 3-4 seconds then stop.Total spin (insertion and additional) should not exceed the guidelines on the box label.
9. Do not overmix. If mixing is continued into the gel lime, the soldifying material may be ground up or displaced trom the rebar, forming an air gap. Loss of anchorage may result.
10. Hold the bolt stationary until the minimum "hold time" is achieved, then tension the bolt. In many cases the hold time will be greater than the minimum time listed.
11. Extra care must used to insure that air-operaled equipment is kept in good running order. Follow the minimum guidelines for air and water pressure. Ensure that all lines are flushed prior to connection.

Limitations

At Coal Operations the annular gap is tightly oontrolled and should be at a minimurn. Recommendation is 4-6mm.

Example
Bar core diameter: 22mm
Hole diameter: 27mm
Annular Gap: 5mm

At Hardrock mines, annular gaps should not exceed 13 mm. If annular gaps exceeding 6 mm are encountered, then bolts must be used that posses larger deformations, and or devices must be used that enhance the mixing of the resin.

In all cases we recommend that the roof be evalualed and short encapsuled pull tests be pertormed to ensure that minimum required load strengths are achieved.

Extended hold times may be due to one or more of the following:

1. Low temperatures
2. Broken ground
3. Weak anchoring material
4. Large hole diameters
5. Over drilled holes
6. High machine torque
7. High break out torque (nuts)
8. lnsufficient spinning

If a bolt fails to reach full installation before stalling, the following may be occurring

1. Crooked holes
2. Displaced / closed holes
3. Fast / Slow ratio not suitable for application
4. Hole too small
5. High temperatures
6. Hot storage conditions
7. Misalignment (mast to hole)
8. Low thrust
9. lnstallation method
10. lncorrect resin / bolt combination
11. Old / out of date resin

Bolt hold times have a natural variance due to one or more of the conditions described above. Consult your local DSI representative or you distributor for further information.

Health and Safety

Suitable safety apparel such as long sleeve clothing, gloves and eye / face protection is extremely important.
In case of eye contact flush with genereus amounts of water and seek medical attention.
In case of contact with skin, wash the affected area. If irritation persists, seek medical attention. Insure that contaminants are removed from clothing.
Material Safety Date Sheets are available from your local DSI representative and on our website.

Quality

DSI Duo Speed Resin Capsules are manufactured to rigorous quality control standards and thoroughly tested before Ieaving the plant. Consult your representative for more details.

Storage

The suggested shelf life is 6 months from date of manufacture. Vigorous stock rotation is highly recommended. Maintaining minimum quantities on hand is also highly desirable. High storage temperature can severely reduce shelf-life. Do not store in direct sunlight. The plastic over wrap causes a greennhouse effect grealty increasing internal temperatures.
Cool storage at 0-5C will minimise storage effects end can extend shelf.life beyond expiration (with testing by and approval of DSI).
If stored at cool temperatures, allow adequate time to warm to ambient temperatur before using. Otherwise, spin and hold limes will be extended.

Packaging

DSI Duo speed resin capsules are available in a range of diameters, lengths and fast/slow ratios. AIl products are color coded and supplied in cardboard cartons with colored labels. Contact your DSI representative for available sizes and special requests.

Volume

An important condition for installing high quality, high strength resin grouted bolts is selecting the correct diameter end length to insure volume requirements are met.

Diameter

Selecting the correct diameter ensures that compaction of the resin grout and displacement of entrained air. In general, the resin diameter should be 2-3mm smaller than the hole diameter.

Length

Selecting the proper length ensures that volumetric requirements are met to obtain a fully grouted bar. A good practice is to exceed the theoretical requirements (in table) by 10% to allow for natural variances in geologic conditions.

24 mm nominal diameter capsule with 22 mm core diameter rebar Theoretical Encapsulation +10%