Pile installation in submerged bearing strata

• US 3,881,320 A
• Filed: 06/27/1973
• Issued: 05/06/1975
• Est. Priority Date: 06/27/1973
• Status: Expired due to Term

• Current Assignee: George J. Gendron
• Original Assignee: George J. Gendron
• Inventors: Gendron, George J.
• Primary Examiner(s): Shapiro, Jacob
• Application Number:
  US05/373,977
• Time in Patent Office: 678 Days
• Field of Search: 61/53.64,53.66,53.7,53.52,53.5,56,56.5,63,50,52,46,53,53.6
• US Class Current: 405/242
• CPC Class Codes: E02D 5/385 with removal of the outer mould-pipes documents also covered by one or several of the groups E02D5/40 - E02D5/44 are classified in all the relevant groups
• CPC Class Codes: E02D 5/48 Piles varying in construction along their length , i.e. along the body between head and shoe, e.g. made of different materials along their length E02D5/50, E02D5/52 take precedence
• CPC Class Codes: E02D 5/72 Pile shoes

Abstract

Piles are installed in locations wherein a bearing stratum is submerged beneath a soft nonsupporting stratum. A tubular displacement element is driven down into the bearing stratum by means of a driving member capable of transmitting dynamic driving forces and load resistance effects from one end to the other. The driving member is than removed and a static load carrying column is installed on the displacement element.

Claims

1. A method of installing a pile in a bearing stratum which underlies a softer non-supporting stratum of earth, said method comprising the steps of detachably fitting an elongated, hollow, tubular, closed bottom overboot over the lower end of an elongated drive member capable of transmitting driving forces applied to its upper end down to the lower end of said overboot, driving said overboot down through the earth and into said bearing stratum by application of said driving forces to the upper end of said drive member until said overboot reaches a depth in said bearing stratum sufficient to produce a predetermined maximum driving resistance but less than the length of said overboot so that at least a portion of the upper end of said overboot extends up beyond said bearing stratum and into said non-supporting stratum, thereafter removing said drive member from said overboot and installing a load carrying column to extend from within said overboot up through said softer stratum.

2. A method according to claim 1 wherein said elongated drive member is capable of accurate transmission of dynamic driving and load resistance forces throughout its length and wherein said application of driving forces to the upper end of said drive member is continued until the response of said upper end to further forces corresponds to the attainment by said overboot of said predetermined driving resistance.

3. A method according to claim 1 wherein said load carrying column is formed by withdrawing said drive member from the earth and filling the space voided by such withdrawal with a castable load carrying material.

4. A method according to claim 3 wherein said castable material is pumped down through the interior of said drive member and out through its bottom end during raising thereof.

5. A method according to claim 1 wherein said overboot is frictionally secured to said drive member in a manner such that it can be forced off by application of fluid pressure through the interior of said drive member.

6. A method according to claim 1 wherein said driving member is caused to extend into the interior of said overboot for driving thereof and wherein, upon completion of driving, a castable substance is forced down through said driving member and into the interior of said overboot.

7. A method according to claim 1 wherein during said driving said overboot is frictionally held to said driving element by frictional sealing means.

8. A method according to clAim 1 wherein during said driving said driving element is caused to apply driving forces to said overboot at different locations along its length.

9. Apparatus for forming a displacement pile, said apparatus comprising an elongated, hollow, closed bottom, tubular overboot, an elongated drive member of substantially greater length than said overboot, the lower end of the said drive member extending into said overboot from the upper end thereof down to its closed bottom, friction type sealing means between said overboot and said drive member for sealing the interior of said overboot and for maintaining said overboot frictionally attached to said drive member, the lower end of said drive member being formed with a cavity coincident with the tubular overboot and a conduit extending down through said drive member and opening into said cavity for directing pressurized fluid down through said drive member and into said overboot for separating said overboot from said drive member.

10. Apparatus according to claim 9 wherein said sealing means comprises O-ring seals extending about the periphery of said drive member near its lower end.

11. Apparatus according to claim 9 wherein said sealing means contact the interior of said overboot near its upper end.

12. Apparatus according to claim 9 wherein the lower end of said drive member engages the bottom of said overboot for pulling same into the earth during driving.

13. Apparatus according to claim 9 wherein said drive member is formed with a shoulder which overlies and engages the upper edge of said overboot for pushing same into the earth during driving.

14. Apparatus according to claim 9 wherein said driving element is formed with an upper shoulder engaging the lower inner edge of an upper shell section for pulling same part way into the earth during driving of said displacement element.

15. A pile installation comprising a load located near the surface of the earth, an elongated pile structure extending from said load down through a soft non-supporting layer of earth down into the interior of a hollow, elongated, tubular overboot, said soft non-supporting layer being incapable of attaining a load supporting characteristic in response to displacement thereof, said overboot extending from an upper location in said non-supporting layer down into a harder supporting layer and displacing said harder supporting layer by an amount such that said supporting layer imposes sufficient resistance on said overboot to support said load.

16. A pile installation according to claim 15 wherein said overboot is a tubular member filled with concrete.

17. A pile installation according to claim 15 wherein said load transmission structure is a column of concrete.