Octagonal Ultra-High Performance Concrete Prestressed Pile System for Deep Foundation Applications

Abstract

An octagonal Ultra-High Performance Concrete prestressed pile system for deep foundation applications utilizes an octagonal cross-sectional geometry with 30-inch flat-to-flat external diameter and central void of 26-32 inches diameter optimized for material efficiency and structural performance. The system employs Ultra-High Performance Concrete with compressive strength exceeding 18,000 pounds per square inch and conventional carbon-steel prestressing strands to provide structural capacity equivalent to steel pile systems. The octagonal geometry with central void targets approximately one cubic yard of UHPC per fifty feet of pile length, enabling direct economic comparison with steel alternatives while providing enhanced durability and reduced dead weight by up to 75%. The system includes modular splice connections for extended length capability and addresses multiple market sectors including high-rise buildings, bridges, industrial facilities, and general infrastructure projects. The octagonal configuration with central void provides superior material utilization compared to conventional square and circular pile geometries while maintaining excellent driving characteristics and structural performance.

Claims

1. (canceled)

2. (canceled)

3. (canceled)

4. (canceled)

5. An octagonal Ultra-High Performance Concrete pile system comprising: an octagonal cross-sectional configuration optimized for material efficiency, Ultra-High Performance Concrete matrix with compressive strength exceeding 18,000 pounds per square inch; carbon-steel prestressing strands and spirals positioned within said octagonal configuration; and standardized 50-foot base length with splice capability for extended lengths; wherein said system provides equivalent structural capacity to steel pile alternatives at approximately one cubic yard of concrete per fifty feet.

6. The octagonal pile system of claim 5, wherein said splice capability enables unlimited length extension while maintaining structural continuity and installation efficiency.

7. The octagonal pile system of claim 5, wherein said octagonal geometry provides optimized material distribution compared to conventional square and circular pile configurations.

8. An octagonal prestressed concrete pile for deep foundation applications comprising: an octagonal Ultra-High Performance Concrete matrix achieving compressive strength exceeding 18,000 pounds per square inch; prestressing strands arranged within said octagonal matrix to provide primary longitudinal reinforcement; and spiral reinforcement configured for said octagonal geometry; wherein said pile provides superior material utilization targeting one cubic yard of concrete per fifty feet while maintaining structural performance equivalent to steel pile systems.

9. The octagonal prestressed pile of claim 8, further comprising mechanical splice connections enabling modular assembly of extended pile lengths.

10. The octagonal prestressed pile of claim 8, wherein said octagonal geometry enables reduced cross-sectional dimensions compared to conventional concrete piles while maintaining equivalent structural capacity.

11. A method of manufacturing octagonal Ultra-High Performance Concrete prestressed piles comprising: preparing Ultra-High Performance Concrete mixture achieving compressive strength exceeding 18,000 pounds per square inch; positioning conventional carbon-steel prestressing strands within octagonal pile forms; casting said UHPC mixture within said octagonal forms around said prestressing strands; and applying prestressing forces to achieve design requirements; wherein said octagonal configuration optimizes material utilization targeting approximately one cubic yard per fifty feet.

12. The method of claim 11, further comprising: incorporating splice connection details during casting; verifying dimensional tolerances specific to octagonal geometry; confirming compressive strength achievement exceeding 18,000 pounds per square inch.

13. (canceled)

14. (canceled)

15. (canceled)

Description

BRIEF DESCRIPTION OF DRAWINGS

[0029] The advantages and features of the present invention will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which:

[0030] FIG. 1 depicts an octagonal Ultra-High Performance Concrete prestressed pile system as used in deep foundation applications;

[0031] FIG. 2 provides a cross-sectional view of the octagonal UHPC pile configuration showing internal prestressing arrangement according to preferred embodiments of the present invention;

[0032] FIG. 3 provides a detailed view of the splice connection system enabling modular length assembly;

[0033] FIG. 4 provides a comparison diagram of material utilization and structural performance between octagonal UHPC piles and conventional pile systems;

[0034] FIG. 5 provides a flow chart for octagonal UHPC pile manufacturing and installation procedures according to the present invention; and

[0035] FIG. 6 provides dimensional specifications and reinforcement details for standardized octagonal pile configurations.

DETAILED DESCRIPTION OF THE INVENTION

[0036] The best mode for carrying out the invention is presented in terms of its preferred embodiment, herein depicted within the Figures. It should be understood that the legal scope of the description is defined by the words of the claims set forth at the end of this patent and that the detailed description is to be construed as exemplary only and does not describe every possible embodiment since describing every possible embodiment would be impractical, if not impossible. Numerous alternative embodiments could be implemented, using either current technology or technology developed after the filing date of this patent, which would still fall within the scope of the claims.

[0037] It should also be understood that, unless a term is expressly defined in this patent there is no intent to limit the meaning of that term, either expressly or by implication, beyond its plain or ordinary meaning, and such term should not be interpreted to be limited in scope based on any statement made in any section of this patent (other than the language of the claims). To the extent that any term recited in the claims at the end of this patent is referred to in this patent in a manner consistent with a single meaning, that is done for sake of clarity only so as to not confuse the reader, and it is not intended that such claim term by limited, by implication or otherwise, to that single meaning. Finally, unless a claim element is defined by reciting the word means and a function without the recital of any structure, it is not intended that the scope of any claim element be interpreted based on the application of 35 U.S.C. 112 (f).

[0038] The best mode for carrying out the invention is presented in terms of its preferred embodiment, herein depicted within the Figures.

1. Detailed Description of the Figures

[0039] The octagonal Ultra-High Performance Concrete prestressed pile system of the present invention addresses the critical need for efficient, high-performance foundation solutions across diverse deep foundation applications. The system utilizes an innovative octagonal cross-sectional geometry combined with advanced Ultra-High Performance Concrete technology to achieve superior material utilization and structural performance.

[0040] Octagonal Geometry and Material Optimization. The octagonal cross-sectional configuration with 30-inch flat-to-flat external diameter represents a significant advancement over conventional square and circular pile geometries.

[0041] The eight-sided geometry provides several distinct advantages: enhanced material distribution efficiency compared to square sections; superior moment capacity compared to circular sections of equivalent cross-sectional area; improved driving characteristics with reduced soil disturbance; optimized concrete volume utilization targeting approximately one cubic yard per fifty feet of pile length; and shape optimized for self-consolidating UHPC flow during casting.

[0042] The central void of 26-32 inches diameter reduces dead weight by up to 75% while maintaining high bending and axial capacity comparable to solid piles. This void reduces dead weight while maintaining structural capacity, making the piles more economical to transport and install.

[0043] The material utilization target of approximately one cubic yard of Ultra-High Performance Concrete per fifty feet of pile length enables direct economic comparison with steel pile alternatives while providing enhanced structural capacity and durability characteristics. This efficiency ratio represents a significant improvement over conventional concrete pile systems that typically require substantially greater concrete volumes to achieve equivalent structural performance.

[0044] Ultra-High Performance Concrete Matrix. The Ultra-High Performance Concrete matrix employed in the present invention achieves compressive strengths exceeding 18,000 pounds per square inch, representing a substantial improvement over conventional concrete systems. The enhanced compressive strength enables reduced cross-sectional dimensions while maintaining superior structural capacity, resulting in improved material efficiency and reduced transportation requirements.

[0045] The UHPC composition comprises carefully proportioned cement, supplementary cementitious materials including silica fume and other pozzolans, optimized aggregate systems, and performance-enhancing admixtures. Steel fiber reinforcement is incorporated to improve tensile ductility, impact resistance, and crack control. The dense microstructure achieved through precise material proportioning and controlled curing procedures provides enhanced durability characteristics across diverse environmental conditions.

[0046] Prestressing System. The prestressing system utilizes conventional carbon-steel prestressing strands arranged within the octagonal cross-section to provide primary longitudinal reinforcement. The prestressing arrangement is optimized for the octagonal geometry with central void, with strand positioning designed to maximize structural efficiency while maintaining adequate concrete cover for durability.

[0047] Conventional carbon-steel spiral reinforcement provides transverse reinforcement and confinement, arranged to complement the octagonal geometry and enhance shear capacity. Internal UHPC spines in void for shear keying and increased torsional resistance. The use of conventional prestressing materials eliminates supply chain constraints and specialty material costs associated with alternative reinforcement systems.

[0048] Modular Length and Splice System. The modular design incorporates standardized 50-foot base segments with engineered splice connections enabling field assembly of extended pile lengths. The splice system maintains structural continuity while providing flexibility for varying foundation requirements. Splice details include mechanical connection systems that transfer prestressing forces and provide moment continuity between segments.

[0049] The modular approach enables transportation of standard-length segments while accommodating unlimited length requirements for deep foundation applications. Splice connections are designed to maintain the structural integrity of continuous pile systems while enabling efficient installation procedures.

2. Operation of the Preferred Embodiment

[0050] The octagonal UHPC pile manufacturing process begins with the preparation of Ultra-High Performance Concrete achieving compressive strengths exceeding 18,000 pounds per square inch. Conventional carbon-steel prestressing strands are positioned within octagonal pile forms according to standardized configurations, with prestressing forces applied to achieve design requirements.

[0051] The octagonal geometry with central void requires specialized forming systems that maintain precise dimensional tolerances while accommodating the prestressing system and void formation. Quality control procedures include compressive strength verification, dimensional tolerance confirmation, and prestressing force validation.

[0052] Installation procedures follow conventional pile driving practices, with the octagonal geometry providing enhanced driving characteristics compared to square sections. The eight-sided configuration reduces soil disturbance during installation while providing superior guidance characteristics compared to circular sections.

[0053] The enhanced material properties of the UHPC matrix enable higher allowable driving stresses, potentially reducing installation time and equipment requirements. The modular splice system enables field assembly of extended lengths as required for specific foundation conditions.

[0054] Target Structural Capacity: Axial capacity of approximately 2,500-3,500 kips and moment capacity up to 3,000 ft-kips (based on FDOT interaction curves) make these piles suitable for high-load applications.

[0055] Suggested Prestressing: The system utilizes conventional prestressing materials with 16 to 20 (7-wire 0.6 diameter strands) arranged symmetrically within the octagonal layout, with approximately 27 kip per strand (75% of 270 ksi UTS capacity) providing optimal prestressing levels.

[0056] The octagonal UHPC pile system provides structural performance equivalent to steel pile alternatives while offering enhanced durability characteristics and material efficiency. The optimized geometry and advanced concrete technology enable reduced cross-sectional dimensions while maintaining superior structural capacity.

[0057] The foregoing descriptions of specific embodiments of the present invention are presented for purposes of illustration and description. The Title, Background, Summary, Brief Description of the Drawings and Abstract of the disclosure are hereby incorporated into the disclosure and are provided as illustrative examples of the disclosure, not as restrictive descriptions. It is submitted with the understanding that they will not be used to limit the scope or meaning of the claims. In addition, in the Detailed Description, it can be seen that the description provides illustrative examples, and the various features are grouped together in various embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed subject matter requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive subject matter lies in less than all features of a single disclosed configuration or operation. The following claims are hereby incorporated into the Detailed Description, with each claim standing on its own as a separately claimed subject matter.

[0058] The claims are not intended to be limited to the aspects described herein but is to be accorded the full scope consistent with the language claims and to encompass all legal equivalents. Notwithstanding, none of the claims are intended to embrace subject matter that fails to satisfy the requirement of 35 U.S.C. 101, 102, or 103, nor should they be interpreted in such a way. Any unintended embracement of such subject matter is hereby disclaimed. They are not intended to be exhaustive nor to limit the invention to precise forms disclosed and, obviously, many modifications and variations are possible in light of the above teaching. The embodiments are chosen and described in order to best explain principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and its various embodiments with various modifications as are suited to the particular use contemplated. It is intended that a scope of the invention be defined broadly by the Drawings and Specification appended hereto and to their equivalents. Therefore, the scope of the invention is in no way to be limited only by any adverse inference under the rulings of Warner-Jenkinson Company, v. Hilton Davis Chemical, 520 US 17 (1997) or Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., 535 U.S. 722 (2002), or other similar caselaw or subsequent precedent should not be made if any future claims are added or amended subsequent to this Patent Application.