Patent US3785200A successfully refreshed from Google Patents.
US3785200A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for in situ borehole testing
Assignee: Iowa State University Research Foundation Inc
•
Filing: 1972-06-01
•
Granted: 1974-01-15
•
Expires: 1992-06-01
Abstract
Abstract Borehole test apparatus includes upper and lower laterally expandable side pressure units joined by a vertically expandable piston and cylinder unit. The laterally expandable side units are provided with diametrically opposing gripper surfaces to exert normal pressure to the sides of the borehole at vertically spaced locations when they are expanded. After the side pressure units are expanded to exert a predetermined normal force, the vertical cylinder unit is expanded to urge the side pressure units apart. One side pressure unit acts as a reaction base and the other shears the soil surrounding the borehole. The maximum vertical separation force tolerated by the soil is a measure of its shearing strength, and is recorded as a function of the normal pressure exerted by the expandable side pressure units to obtain the cohesion C and internal friction angle of the soil, rock, or other material tested.
Inventors
- 👤 R Handy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:54
CPC Classifications
E; E21; E21B; E21B49/00; E21B49/006
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
119 words
Apparatus for use in measuring properties of soil in a borehole comprising: upper and lower laterally expandable side fluid-actuated pressure units, each unit including first and second soil-engaging surfaces of fixed area conforming to opposite portions of said borehole and fluid pressure means for selectively moving said surfaces apart to engage said soil at opposite locations in said borehole to apply a predetermined normal pressure thereto; and a vertically expandable fluid pressure unit interconnecting said upper and lower units and being selectively actuatable to urge said upper and lower units relative to eacH other; whereby a relationship between normal pressure developed by the side pressure units and quick shear force developed by the vertically expandable unit may be developed.
Claim 2
Dependent Claim
119 words
Apparatus for use in measuring properties of soil in a borehole comprising: upper and lower laterally expandable side fluid-actuated pressure units, each unit including first and second soil-engaging surfaces of fixed area conforming to opposite portions of said borehole and fluid pressure means for selectively moving said surfaces apart to engage said soil at opposite locations in said borehole to apply a predetermined normal pressure thereto; and a vertically expandable fluid pressure unit interconnecting said upper and lower units and being selectively actuatable to urge said upper and lower units relative to eacH other; whereby a relationship between normal pressure developed by the side pressure units and quick shear force developed by the vertically expandable unit may be developed.
Claim 3
Dependent Claim
44 words
The system of claim 1 further comprising cylindrical shield means for covering said apparatus when said apparatus is lowered into a borehole and adapted to be selectively withdrawn to expose said upper and lower units to engage the soil after removal of said shield.
Claim 4
Dependent Claim
84 words
The system of claim 1 wherein said vertically expandable means includes a piston rod and cylinder unit, said system further comprising means for connecting one movable portion of said piston rod and cylinder unit to both side sections of said upper side pressure unit while permitting lateral expansion thereof, and means for connecting the other movable portion of said piston rod and cylinder unit to both side sections of said lower side pressure unit while permitting the side sections thereof to move freely sideways.
Claim 5
Dependent Claim
58 words
The system of claim 1 wherein each of said upper and lower side pressure units includes fluid pressure means for selectively urging the two side sections thereof in a contracted or expanded condition, said system further comprising flexible fluid coupling means for coupling the expansion fluid of said upper side pressure unit to said lower side pressure unit.
Claim 6
Dependent Claim
166 words
Borehole testing apparatus comprising: upper and lower laterally expandable side pressure units, each unit including first and second side sections; means for mounting said side sections together while permitting lateral expansion and contraction thereof, each side section being provided with a soil-engaging surface; a piston rod and cylinder unit having first and second relatively movable portions, one portion being connected to said upper side pressure unit and the other portion being connected to said lower side pressure unit; and fluid pressure means for selectively expanding or contracting the side sections of said upper and lower side pressure units in unison to apply a measurable normal pressure in said borehole, whereby said side pressure units may first be expanded to exert a predetermined normal pressure at a location in said borehole, and said piston rod and cylinder unit may then be actuated to urge said side pressure units relative to one another to exert a shearing force on the consolidated soil at said location of said borehole.
Claim 7
Dependent Claim
166 words
Borehole testing apparatus comprising: upper and lower laterally expandable side pressure units, each unit including first and second side sections; means for mounting said side sections together while permitting lateral expansion and contraction thereof, each side section being provided with a soil-engaging surface; a piston rod and cylinder unit having first and second relatively movable portions, one portion being connected to said upper side pressure unit and the other portion being connected to said lower side pressure unit; and fluid pressure means for selectively expanding or contracting the side sections of said upper and lower side pressure units in unison to apply a measurable normal pressure in said borehole, whereby said side pressure units may first be expanded to exert a predetermined normal pressure at a location in said borehole, and said piston rod and cylinder unit may then be actuated to urge said side pressure units relative to one another to exert a shearing force on the consolidated soil at said location of said borehole.
Claim 8
Dependent Claim
27 words
The apparatus of claim 5 further comprising means for measuring the fluid pressure in said cylinder and piston rod unit which pressure is representative of shear force.
Claim 9
Dependent Claim
26 words
The system of claim 5 wherein said piston rod and cylinder unit is arranged to force said upper and lower side pressure units apart during test.
References Cited (Backward Citations)
US3233315A
Cited
US3562916A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-14 | 1977-07-16 | 1978-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-14 | 1981-07-16 | 1982-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-14 | 1985-07-16 | 1986-01-15 | $7700.00 | Window Closed / Lapsed |