Patent US2190825A successfully refreshed from Google Patents.
US3849992A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Reinforcing elements for stabilization of rocks
Assignee: Exchem Holdings Ltd
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Filing: 1973-05-23
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Granted: 1974-11-26
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Expires: 1993-05-23
Abstract
Abstract The stabilisation of weak rock formations, such as longwall coal faces in underground mines, is effected by inserting into a borehole drilled in the rock formation a reinforcing assembly in which a plurality of longitudinally extending annular segments are fixedly disposed in longitudinally staggered relationship about a coaxially arranged inner tube, feeding through the inner tube a bonding composition so as to cause it to flow back from the closed end of the borehole to the annular space at the mouth of the borehole, and allowing the bonding composition to harden so as to bond the reinforcing assembly to the rock formation.
Inventors
- 👤 J Murphy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 15:21
CPC Classifications
E; E21; E21D; E21D20/00; E21D20/02
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
226 words
A method of reinforcing an underground rock formation positioned above a coal seam being mined by the longwall system, which method comprises drilling into the rock formation a substantially horizontal borehole having a diameter less than 50 mm. and a length in excess of about 40 feet; inserting into the borehole in stages a reinforcing assembly comprising a plurality of lengths of longitudinally extending annular segments fixedly disposed in longitudinally staggered relationship with respect to each other about a coaxially arranged inner tube, said assembly being made up from a plurality of the lengths of said annular segments while being inserted into the borehole, and the insertion of the reinforcing assembly being continued until the inner end thereof lies adjacent to the inner end portion of the borehole and the outer end of the reinforcing assembly lies adjacent to the mouth of the borehole; feeding a bonding composition through the inner tube of the reinforcing assembly so as to cause the bonding composition to flow out of the inner end of the reinforcing assembly and back along the annular space between the assembly and the wall of the borehole; continuing the feeding of the bonding composition until the said annular space is substantially full of bonding composition; and thereafter allowing the bonding composition to harden so as to bond the reinforcing assembly to the rock formation.
Claim 2
Independent Claim
226 words
A method of reinforcing an underground rock formation positioned above a coal seam being mined by the longwall system, which method comprises drilling into the rock formation a substantially horizontal borehole having a diameter less than 50 mm. and a length in excess of about 40 feet; inserting into the borehole in stages a reinforcing assembly comprising a plurality of lengths of longitudinally extending annular segments fixedly disposed in longitudinally staggered relationship with respect to each other about a coaxially arranged inner tube, said assembly being made up from a plurality of the lengths of said annular segments while being inserted into the borehole, and the insertion of the reinforcing assembly being continued until the inner end thereof lies adjacent to the inner end portion of the borehole and the outer end of the reinforcing assembly lies adjacent to the mouth of the borehole; feeding a bonding composition through the inner tube of the reinforcing assembly so as to cause the bonding composition to flow out of the inner end of the reinforcing assembly and back along the annular space between the assembly and the wall of the borehole; continuing the feeding of the bonding composition until the said annular space is substantially full of bonding composition; and thereafter allowing the bonding composition to harden so as to bond the reinforcing assembly to the rock formation.
Claim 3
Dependent Claim
39 words
A method according to claim 1, wherein the reinforcing assembly comprises a continuous inner tube about which are fixedly disposed a plurality of lengths of longitudinally extending annular segments in longitudinally staggered relationship with respect to the inner tube.
Claim 4
Dependent Claim
17 words
A method according to claim 1, wherein each length of the annular segments is semi-cylindrical in shape.
Claim 5
Dependent Claim
17 words
A method according to claim 3, wherein each length of the annular segments is semi-cylindrical in shape.
Claim 6
Dependent Claim
27 words
A method according to claim 1, wherein the inner end of the reinforcing assembly is provided with a tubular perforated ejection head having a closed front end.
Claim 7
Dependent Claim
22 words
A method according to claim 5, wherein the ejection head has a generally cylindrical body which tapers towards the closed front end.
Claim 8
Dependent Claim
30 words
A method according to claim 6, wherein the ejection head is formed with a plurality of exit apertures which are substantially symmetrically disposed around the body of the ejection head.
Claim 9
Dependent Claim
17 words
A method according to claim 1, wherein the bonding composition is an unsaturated polyester resin based composition.
Claim 10
Dependent Claim
92 words
A longhole reinforcing assembly for use in a substantially horizontal borehole formed in an underground formation being mined by the longwall system, said assembly having a length in excess of about 40 feet, and comprising in combination a plurality of lengths of longitudinally extending annular segments fixedly disposed in longitudinally staggered relationship with respect to each other about a co-axially arranged inner tube providing an axial passage throughout the length of said reinforcing assembly for conducting a bonding composition into the annular space between said assembly and the wall of said borehole.
Claim 11
Dependent Claim
92 words
A longhole reinforcing assembly for use in a substantially horizontal borehole formed in an underground formation being mined by the longwall system, said assembly having a length in excess of about 40 feet, and comprising in combination a plurality of lengths of longitudinally extending annular segments fixedly disposed in longitudinally staggered relationship with respect to each other about a co-axially arranged inner tube providing an axial passage throughout the length of said reinforcing assembly for conducting a bonding composition into the annular space between said assembly and the wall of said borehole.
Claim 12
Dependent Claim
47 words
A reinforcing assembly as claimed in claim 9, wherein that end of the reinforcing assembly which is to be positioned adjacent the closed end of the borehole is provided with a tubular perforated ejection head having a generally cylindrical body which tapers towards a closed front end.
Claim 13
Dependent Claim
32 words
A reinForcing assembly as claimed in claim 10, wherein the ejection head is formed with a plurality of exit apertures which are substantially symmetrically disposed around the body of the ejection head.
Claim 14
Dependent Claim
19 words
A reinforcing assembly as claimed in claim 9, wherein each length of the annular segments is semi-cylindrical in shape.
Claim 15
Dependent Claim
16 words
A reinforcing assembly as claimed in claim 9, wherein said inner tube is a continuous tube.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-11-25 | 1978-05-27 | 1978-11-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-25 | 1982-05-27 | 1982-11-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-25 | 1986-05-27 | 1986-11-26 | $7700.00 | Window Closed / Lapsed |