US3797254A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Consolidation of rock strata
Assignee: Explosives & Chem Prod
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Filing: 1972-02-28
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Granted: 1974-03-19
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Expires: 1992-02-28
Abstract
Abstract The consolidation of friable rock strate found in, for example, underground roadways and tunnels encountered in mining and civil engineering is effected by the use of a hollow tubular reinforcing member having enlarged end portions in a borehole having a diameter which is at least 4 mm. greater than that of the unenlarged portion of the reinforcing member. It is possible to install such reinforcing members using relatively simple handheld drilling machines, and to provide the reinforcing member with an inner calibrated rod capable of indicating an increase in stress within the tubular member.
Inventors
- 👤 A Askey
- 👤 J Murphy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 11:33
CPC Classifications
E; E21; E21D; E21D21/00; E21D21/0026; E21D21/0033
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
108 words
A method of consolidating friable rock strata, characterized in that a tubular reinforcing member having preformed enlarged end portions is secured with a bonding material in an oversized borehole drilled in the friable rock strata with one enlarged end portion of said tubular member being positioned adjacent the inner end of said borehole and the other enlarged end portion being retained in a position adjacent the mouth of said borehole by means of a bearing plate, the diameter of the borehole being such that there is an annular clearance between the wall of the borehole and the body portion of the reinforcing member of at least 2 mm.
Claim 2
Independent Claim
108 words
A method of consolidating friable rock strata, characterized in that a tubular reinforcing member having preformed enlarged end portions is secured with a bonding material in an oversized borehole drilled in the friable rock strata with one enlarged end portion of said tubular member being positioned adjacent the inner end of said borehole and the other enlarged end portion being retained in a position adjacent the mouth of said borehole by means of a bearing plate, the diameter of the borehole being such that there is an annular clearance between the wall of the borehole and the body portion of the reinforcing member of at least 2 mm.
Claim 3
Dependent Claim
16 words
A method according to claim 1, wherein the annular clearance is from 3 to 5 mm.
Claim 4
Dependent Claim
59 words
A method according to claim 1, wherein said other enlarged end portion of the tubular reinforcing member projects from the mouth of the borehole when the tubular member has been positioned therein and said bearing plate is secured to said projecting end portion so as to be in contact with the rock adjacent to the mouth of the borehole.
Claim 5
Dependent Claim
22 words
A method according to claim 3, wherein said projecting end portion is provided with means for securing the bearing plate in position.
Claim 6
Dependent Claim
18 words
A method according to claim 1, wherein the tubular reinforcing member is formed from a metal or alloy.
Claim 7
Dependent Claim
15 words
A method according to claim 5, wherein the tubular reinforcing member is formed from steel.
Claim 8
Dependent Claim
62 words
A method according to claim 1, wherein the tubular reinforcing member is provided with a solid indicator rod extending lengthwise thereof, the rod being secured to the inner enlarged end portion of said tubular member and projecting from the other end portion of said member so as to be capable of indicating any longitudinal extension of the tubular member when in use.
Claim 9
Dependent Claim
28 words
A method according to claim 1, wherein the tubular reinforcing member is secured in the borehole by means of a bonding material consisting of a polyester-based resin composition.
Claim 10
Dependent Claim
58 words
A method according to claim 8, wherein said resin composition is contained in at least one multi-component single compartment cartridge which is inserted into the borehole prior to the insertion therein of the tubular reinforcing member, the latter being rotated during insertion so as to cause the contents of the cartridge to be released and mixed in situ.
Claim 11
Dependent Claim
39 words
A method according to claim 9, wherein a sufficient number of cartridges is used to ensure that the annular space between the wall of the borehole and the tubular reinforcing member is substantially completely filled with the resin composition.
References Cited (Backward Citations)
US1696861A
Cited
US2492164A
Cited
US2682152A
Cited
US2879686A
Cited
DE1178815B
Cited
US3430449A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-18 | 1977-09-17 | 1978-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-18 | 1981-09-17 | 1982-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-18 | 1985-09-17 | 1986-03-19 | $7700.00 | Window Closed / Lapsed |