US3859798A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of constructing a flexible sand in the soft ground
Assignee: Chiyoda Corp
•
Filing: 1973-07-23
•
Granted: 1975-01-14
•
Expires: 1993-07-23
Abstract
Abstract A sand drain comprising a tubular protector 5 to 25 cm in diameter prepared by weaving monofilaments in the lattice form to provide a mesh area of 2.0 to 3.0 mm2 and the sand filled into the protector to form a sand pillar, which, after constructed in soft ground, can be rendered flexible so as to match any displacement of strata of the soft ground, thereby preventing breakage of the sand pillar from breakage.
Inventors
- 👤 Osamu Terashima
- 👤 Ikuo Okabayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:43
CPC Classifications
E; E02; E02D; E02D13/00; E02D13/04; E02B; E02B11/00; E02D3/00; E02D3/02; E02D3/10; E02D3/103
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
187 words
A method for constructing flexible sand drains in soft ground which includes the steps of: arranging in a regular polygonal form a plurality of casings having a sufficient large inner diameter to receive protectors comprising monofilament woven fabric having sufficiently large meshes to peRmit the passage of part of the sand filled in said protector, and provided at the top with a freely operable sealing cover; driving said casings into said soft ground at the same time by a vibro-hammer mounted on a pile driver; connecting the upper ends of said protectors to the outlets of a hopper mounted on said pile driver after said protectors are inserted into said casings and filling sand in said protectors by the vibration of said vibro-hammer to form sand pillars; introducing compressed air into said casings with the respective sealing covers closed; pulling said casings alone out of said soft ground while being vibrated by said vibro-hammer with the lubricating action of the sand passing through a gap between said casings and protectors, thereby firmly setting in said soft ground sand drains comprising said protectors and sand pillars contained therein.
Claim 2
Independent Claim
187 words
A method for constructing flexible sand drains in soft ground which includes the steps of: arranging in a regular polygonal form a plurality of casings having a sufficient large inner diameter to receive protectors comprising monofilament woven fabric having sufficiently large meshes to peRmit the passage of part of the sand filled in said protector, and provided at the top with a freely operable sealing cover; driving said casings into said soft ground at the same time by a vibro-hammer mounted on a pile driver; connecting the upper ends of said protectors to the outlets of a hopper mounted on said pile driver after said protectors are inserted into said casings and filling sand in said protectors by the vibration of said vibro-hammer to form sand pillars; introducing compressed air into said casings with the respective sealing covers closed; pulling said casings alone out of said soft ground while being vibrated by said vibro-hammer with the lubricating action of the sand passing through a gap between said casings and protectors, thereby firmly setting in said soft ground sand drains comprising said protectors and sand pillars contained therein.
Claim 3
Dependent Claim
37 words
The method of constructing flexible sand drains according to claim 1 wherein, prior to the driving of said casings into said soft ground, said protectors are inserted into said casings and sand is placed in said protectors.
Claim 4
Dependent Claim
53 words
The method of constructing flexible sand drains in soft ground according to claim 2 wherein said casings are driven into soft ground under water by a power transmitting rod provided between said vibro-hammer and casings until the upper ends of said casings are brought close to the surface of said under water ground.
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) | 1978-01-13 | 1978-07-15 | 1979-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-13 | 1982-07-15 | 1983-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-13 | 1986-07-15 | 1987-01-14 | $7700.00 | Window Closed / Lapsed |