← Back to Patent Explorer
US3720065A Expired / Lapsed US ⏱️ 0.0 years remaining

Making holes in the ground and freezing the surrounding soil

Assignee: Individual
•
Filing: 1971-07-06
•
Granted: 1973-03-13
•
Expires: 1991-07-06
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A method and apparatus for forming holes in the ground and for freezing the soil forming the walls of the holes for the purpose of temporarily solidifying zones of unstable soil adjacent to excavations and for forming open holes in unstable soil below the water table that are useable to make cast-in-place concrete piling, sand drains and water wells. The general method comprises the steps of forming a hole in the ground by driving or pushing a mandrel downward, which mandrel has a stem with cross-sectional area smaller than a drive foot on its lower end; supplying a flowable material in the space in the ground around the mandrel stem which prevents the hole from caving in, keeps the ground water out of the hole and freezes the soil surface comprising the walls of the hole.

Inventors

  • 👤 J Sherard

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 08:46
CPC Classifications
E; E02; E02D; E02D5/00; E02D5/22; E02D5/34; E02D5/36; E02D3/00; E02D3/02; E02D3/10; E02D3/11; E02D3/115

Claims Analysis

Total Claims: 19
Claim 1
Independent Claim 218 words
A method of forming a hole in thE ground and freezing the surrounding soil comprising the steps: a. providing a mandrel having a straight stem section and a drive foot at or near its lower end, said drive foot having a cross sectional area in the direction transverse to the mandrel axis which is larger than the transverse cross sectional area of the solid portion of the mandrel stem; b. moving said mandrel downwardly to cause said drive foot to penetrate into the ground so that an elongated hole is formed, the area of which hole is larger than the cross-sectional body area of the mandrel stem, thus creating a longitudinal space in the ground adjacent the mandrel stem behind said downward penetrating drive foot; c. simultaneously with the downward penetration of the mandrel causing a liquefied gas to flow into said longitudinal space, said liquefied gas having the property that it will absorb heat and change its state from a liquid to a gaseous form under atmospheric conditions; d. simultaneously with downward movement of the mandrel, freezing the walls of the hole and creating a strong and impervious skin of frozen soil on said wall; and e. removing the mandrel from the ground leaving an open hole with frozen walls filled only with gas at atmospheric pressure.
Claim 2
Independent Claim 218 words
A method of forming a hole in thE ground and freezing the surrounding soil comprising the steps: a. providing a mandrel having a straight stem section and a drive foot at or near its lower end, said drive foot having a cross sectional area in the direction transverse to the mandrel axis which is larger than the transverse cross sectional area of the solid portion of the mandrel stem; b. moving said mandrel downwardly to cause said drive foot to penetrate into the ground so that an elongated hole is formed, the area of which hole is larger than the cross-sectional body area of the mandrel stem, thus creating a longitudinal space in the ground adjacent the mandrel stem behind said downward penetrating drive foot; c. simultaneously with the downward penetration of the mandrel causing a liquefied gas to flow into said longitudinal space, said liquefied gas having the property that it will absorb heat and change its state from a liquid to a gaseous form under atmospheric conditions; d. simultaneously with downward movement of the mandrel, freezing the walls of the hole and creating a strong and impervious skin of frozen soil on said wall; and e. removing the mandrel from the ground leaving an open hole with frozen walls filled only with gas at atmospheric pressure.
Claim 3
Dependent Claim 35 words
The method of claim 1 in which said liquefied gas is caused to fill said space by flowing downwardly into the ground under the action of gravity from a source of supply at the surface.
Claim 4
Dependent Claim 26 words
The method of claim 1 in which said liquefied gas is caused to flow into said longitudinal space by pumping it down through a closed conduit
Claim 5
Dependent Claim 12 words
The method of claim 1 in which said liquefied gas is nitrogen.
Claim 6
Dependent Claim 41 words
The method of claim 1 including the extra step of detaching said mandrel stem from said drive foot and leaving said drive foot in the ground at the bottom of the hole when the mandrel stem is withdrawn from the ground.
Claim 7
Dependent Claim 75 words
The method as described in claim 1 wherein said mandrel stem section has a hollow interior sand said drive foot has a central opening so that some of the soil lying in the path of the downward penetrating mandrel enters the interior of the mandrel stem in the form of a soil plug, said soil plug remaining inside said mandrel stem and being removed from the ground with it during its withdrawal from the hole.
Claim 8
Independent Claim 235 words
An apparatus for forming an open cylindrical hole in the ground extending downwardly from the ground surface, which hole will remain temporarily open and free from ground water, even in unstable soil below the water table, because a skin of soil comprising the wall of the hole is frozen, comprising: a. a rigid elongated mandrel means for making a hole in the ground having a main stem portion and a drive foot at its lower end, said drive foot having a cross-sectional area in the transverse direction to the mandrel axis which is larger than the solid transverse cross-sectional area of the mandrel stem; b. driving means for exerting a downward force on the upper end of said mandrel stem, thereby causing it to penetrate and form a hole in the ground, and thereby creating a longitudinal space adjacent to said mandrel stem behind said downward moving drive foot; c. means for causing liquefied gas to flow into said longitudinal space directly above said drive foot of said mandrel means as it is moved downwardly, said liquefied gas having the property that it absorbs heat and changes state from the liquid to a gaseous form under atmospheric conditions, thereby freezing the soil walls of the hole to prevent them from collapsing and to prevent any ground water in the adjacent soil from entering said space; and d. means for withdrawing said mandrel from the ground.
Claim 9
Independent Claim 235 words
An apparatus for forming an open cylindrical hole in the ground extending downwardly from the ground surface, which hole will remain temporarily open and free from ground water, even in unstable soil below the water table, because a skin of soil comprising the wall of the hole is frozen, comprising: a. a rigid elongated mandrel means for making a hole in the ground having a main stem portion and a drive foot at its lower end, said drive foot having a cross-sectional area in the transverse direction to the mandrel axis which is larger than the solid transverse cross-sectional area of the mandrel stem; b. driving means for exerting a downward force on the upper end of said mandrel stem, thereby causing it to penetrate and form a hole in the ground, and thereby creating a longitudinal space adjacent to said mandrel stem behind said downward moving drive foot; c. means for causing liquefied gas to flow into said longitudinal space directly above said drive foot of said mandrel means as it is moved downwardly, said liquefied gas having the property that it absorbs heat and changes state from the liquid to a gaseous form under atmospheric conditions, thereby freezing the soil walls of the hole to prevent them from collapsing and to prevent any ground water in the adjacent soil from entering said space; and d. means for withdrawing said mandrel from the ground.
Claim 10
Dependent Claim 38 words
The apparatus as described in claim 7 wherein said means for causing said liquefied gas to flow into said space comprises a reservoir on the ground surface surrounding the mandrel which reservoir is filled with said liquefied gas.
Claim 11
Dependent Claim 31 words
The apparatus as described in claim 7 wherein said means for causing said liquefied gas To flow into said space comprises means for pumping said liquefied gas down into the ground.
Claim 12
Dependent Claim 18 words
The apparatus as described in claim 7 wherein said drive foot is detachable from said mandrel stem portion.
Claim 13
Dependent Claim 53 words
The apparatus as described in claim 7 wherein said mandrel stem is a hollow sleeve and said drive foot is an annulus, so that a portion of the soil in the path of the downward penetrating mandrel is caused to enter the interior of the mandrel in the form of a soil plug.
Claim 14
Dependent Claim 37 words
The apparatus as described in claim 11 including means at the lower end of said mandrel stem for forming a space around said soil plug as it enters the hollow interior of said hollow sleeve mandrel stem.
Claim 15
Dependent Claim 27 words
The apparatus as described in claim 12 including means for causing said liquefied gas to flow into said space around said soil plug inside said mandrel stem.
Claim 16
Dependent Claim 32 words
The apparatus as described in claim 13 used particularly for the purpose of taking undisturbed soil samples wherein said annular drive foot is beveled to a knife point at its lower end.
Claim 17
Dependent Claim 48 words
The apparatus as described in claim 7 in which said drive foot has a sheet metal skirt attached to its upper side for the purpose of providing temporary support to the solid forming the walls of the newly created hole until such time as the soil is frozen.
Claim 18
Independent Claim 100 words
A method for making an uncased hole in the ground comprising the steps of: forming the hole progressively from the ground surface downward; placing a liquefied gas continuously in the lower part of the hole, said liquefied gas being in direct contact with the ground material forming the walls of the hole, said liquefied gas having the property that it absorbs heat and changes state from the liquid to the gaseous form under atmospheric conditions, and simultaneously creating a strong and impervious skin of frozen soil on said walls immediately as they are formed at the bottom of the hole.
Claim 19
Independent Claim 100 words
A method for making an uncased hole in the ground comprising the steps of: forming the hole progressively from the ground surface downward; placing a liquefied gas continuously in the lower part of the hole, said liquefied gas being in direct contact with the ground material forming the walls of the hole, said liquefied gas having the property that it absorbs heat and changes state from the liquid to the gaseous form under atmospheric conditions, and simultaneously creating a strong and impervious skin of frozen soil on said walls immediately as they are formed at the bottom of the hole.

References Cited (Backward Citations)

US1127393A Cited
US1975162A Cited
US2621022A Cited
US2562860A Cited
US3075588A Cited
US3163241A Cited
US3221558A Cited
US3358763A Cited
US3318394A Cited
US3420063A Cited
US3540225A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-03-12 1976-09-11 1977-03-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-03-12 1980-09-11 1981-03-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-03-12 1984-09-11 1985-03-13 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag