Foundation assembly for supporting infrastructure in natural environments

Abstract

A foundation assembly for supporting infrastructure in natural environments. Examples of such infrastructure include elevated walkways, elevated pedestrian assembly areas, pedestrian bridges, towers, electrical or other equipment. The foundation assembly comprises numerous small diameter rods installed in the ground at various angles, all affixed by a system of rod clamp assemblies and clamp plates to a frame pipe usually set close to and parallel to the ground. The pile system is particularly suited to areas with poor access, wet conditions, steep slopes and soils that contain boulders or increase in density with increasing depth.

Description

[0001] Foundation Assembly for Supporting Infrastructure in Natural Environments

[0002] Field of the Invention

[0003] The invention pertains to foundation systems for supporting infrastructure, particularly in natural environments where it is not convenient or possible to use traditional foundation systems.

[0004] Background of the Invention

[0005] Conventional foundation design requires the installation of foundation elements either driven or screwed into the ground, or assembled within excavated holes (cast in place concrete). These installations are usually on a very strict grid / layout according to a preconceived site specific plan. This rigidity of design can cause construction delays when unexpected conditions (such as a large rocks) are encountered and the design has to be changed and project components re-ordered.

[0006] Conventional concrete foundations require excavation, excavation equipment, fill storage or removal, and transport of either precast or wet concrete to the project site. For linear hillside or remote infrastructure, the use of concrete is very expensive and time consuming.

[0007] Screw piles and large drilled and grouted piles or anchors are often used for the support of infrastructure. While this can be successful in areas where access is suitable, it is often the case that the pile installation machines (that drill or turn the piles into the ground) require a small road to be built to gain site access. This is often not practical on hillsides or remote sites.

[0008] Conventional methods of foundation installation often require ground disturbance for installation. Even screw pile or larger driven pile options require access roads to be cut to permit installation. Ground disturbance results in possible risks which include introduction of weed species on exposed soils, soil erosion, soil stability concerns, vegetation loss, vegetation re-establishment requirements and the maintenance thereof. Conventional screw piles, driven piles and concrete pillars can often require site specific fabricated bracing to hold the installed support vertical.

[0009] Traditional wood foundations such as cribs or driven posts have service durations limited by wood decay. Wood foundations are also usually installed at or near the ground surface. As a result, they are very susceptible to frost heave and slope creep issues, both of which deform and degrade the supported infrastructure.

[0010] Currently, small elevated structures are typically supported by pile bents, single piles, cast in place concrete, precast concrete, or wood assemblies.

[0011] Pile Bents: Piles are driven, vibrated or rotated into the ground in a set pattern with a specific predetermined count and placement followed. The tops are then connected permanently together to form support for the structure above. Examples of the use of this technology include wharfs, bridge supports, marine beacon supports, buildings built over soils that require improvement by the insertion of piles, and buildings built on grids of piles placed in a specific pattern. These methods can be suitable for larger heavy infrastructure on sites that are level with good acess, but their application in lesser load environments, and on steep ground is not practical.

[0012] Single piles: A single pile or pile pair is driven, vibrated or rotated into the ground and the load placed on top. In hillside applications, access for the equipment to place the piles is problematic, requiring the construction of temporary access roads, etc. As well, the deployment of single piles or pile pairs typically does not provide enough lateral stability for the system in hillside environments. If a boulder or unsuitable conditions are found, relocation and re-design are required. Soil creep, erosion, load symmetry and load height all contribute to lateral instability in tall single or pile pair installations.

[0013] Grouted micro piles: This technology requires that a hole be drilled into the soils, and a rod inserted that is subsequently grouted into position with pumped-in grout. These assemblies have some flexibility in installation in that several can be placed in a tight sloping grouping. The top of the installed grouping is then connected via a pile cap assembly (either steel, or concrete) that unifies the tops of the individual pile grouping such that a bearing point is created for the loads above. This system will provide sufficient support but requires the mobilization to each support location of drilling and grouting equipment, as well as the assembly (weld or cast in place concrete) of a site specific pile cap.

[0014] Cast in place concrete: Concrete can be successfully placed on hillsides but considerable effort is needed to excavate and form prior to pouring. Access for the placement of concrete can require temporary access roads or concrete pumping. Excavation on hillsides can create slope stability issues for the excavated material and safety issues for the workers. Excavation in remote settings is time consuming and therefore expensive.

[0015] Wood assemblies such as cribs or sleepers have been frequently used to support walkways, steps, stairs, etc. in remote locations. Wood, however, ultimately decays and requires replacement. On steep slopes, wood cribs or sleepers must be firmly bedded into the hillside to avoid movement. There are attendant labour and excavation requirements that can make wood assemblies unsuitable at least in the long term.

[0016] There remains a need for an effective foundation assembly which avoids the disadvantages of these existing systems.

[0017] Summary of the Invention

[0018] In naturally sloping, unvegetated or maturely vegetated lands or hillsides there is the need to install foundations for the support of infrastructure. Examples of such infrastructure include elevated walkways, elevated pedestrian assembly areas, pedestrian bridges, towers, electrical or other equipment, etc. The pile system of the invention comprises numerous small diameter rods installed where they can be, all tied into a frame set close to and parallel to the ground surface. The installation of the rods may be done by driving them into the ground, or by drilling holes and securing the rods in the drilled holes, for example with grout or epoxy. The pile system is particularly suited to areas with poor access, steep slopes and soils that contain boulders and / or increase in density with increasing depth. The frame serves as a stable firm base for the support of infrastructure.

[0019] The present invention has several beneficial attributes. First, the small diameter piles can be hand driven with a sledge hammer. They can be carried overland by a person to the installation site. In areas of exposed bedrock, small diameter holes can be hammer drilled into the bedrock in the desired locations, and the rods can be inserted and secured using grout, epoxy, etc. The frame is also assembled on site and its components can be hand carried and positioned.

[0020] Second, the location of the piles and their angle of installation (degrees off vertical) is determined by the installer at the time of installation. There is an adjustable connector for each pile pair at the frame that can be moved and rotated in the field before tightening to a permanent connection.

[0021] Third, there is no need for any ground disturbance. The piles are simply driven or otherwise installed through the vegetation “as is” into the soils below. Vegetation is allowed to continue to grow through the frame if desired or allowed. In areas where archeological values may exist, this “no disturbance” attribute can make a project allowable and minimally invasive. The lack of disturbance also minimizes the need for revegetation, erosion control and soil removal during or after infrastructure installation.

[0022] Fourth, if locally unsuitable ground conditions, such as a boulder, are discovered, the individual pile location or angle can be altered to work around the boulder. If a pile encounters a rock or other condition at some depth, the pile may be simply left tied into the frame, and more piles in other parts of the frame are added to compensate.

[0023] Fifth, the frame can be installed at any angle determined to be suitable in the field at the time of installation. This allows the frame to be positioned close to the ground for maximum stability and load capacity.

[0024] The foundation assembly of the invention can be used to replace traditional screw piles, driven piles, grouted pile assemblies, and concrete foundation options for elevated infrastructure in flat or sloping natural environments. The installed frames can be used to permanently support any object or assembly, limited only by the structural capacity of the frame and pile cluster.

[0025] Examples of park infrastructure that can be supported by the foundation assembly of the invention include stairways and walkways on steep slopes within parks, avoiding the difficult installation of concrete, wooden assemblies, screw pile or driven pile foundations.

[0026] The support of an abutment tower for a pedestrian footbridge is also a practical use of the foundation assembly. The ground near mountain streams can be very sensitive to disturbance, and the small rods used in the invention do not require any excavation and can be moved about to feel for soil pockets and recesses that can support the tower loads.

[0027] On steep mountainside hills, excavation for concrete foundations, or access construction for screw pile installation, is not practical. The foundation assembly of the invention avoids such disturbance with a system that provides equal or superior long term permanent structural support.

[0028] It is often the case that small swampy areas are to be crossed. Conventionally, these are crossed with screw piles or driven piles. These require bracing which has to be connected to each pile below water level. Working below water level is expensive to complete safely. Using the present invention, where the bottom of the swampy area is close, the frame can be set above water level and the numerous rods driven in at angles that provide both the structural capacity and the required lateral bracing. With the foundation assembly of the invention, no work is done under the water surface.

[0029] According to one embodiment of the invention there is provided a foundation assembly for supporting infrastructure, comprising: (a) a plurality of spaced apart pairs of rods installed in the ground such that the upper ends of the rods of a respective pair project above the ground adjacent to each other, some of the rods projecting from the ground at an angle relative to others of the rods; (b) a frame pipe extending between the adjacent rods of each pair of rods; (c) means for affixing the frame pipe to the rods, comprising: (i) a plurality of rod clamp assemblies, each being affixed to a respective rod that extends through a bore in the rod clamp assembly, each rod clamp assembly having a bolt; (ii) a plurality of clamp plates, each having two holes for passage of the bolts of two rod clamp assemblies; wherein the rods of an adjacent pair of rods are affixed to the frame pipe by means of two rod clamp assemblies and two clamp plates.

[0030] According to another aspect of the invention there is provided a method of making a foundation assembly for supporting infrastructure, comprising the steps of: (a) installing a plurality of spaced apart pairs of rods in the ground such that the upper ends of the rods of a respective pair project above the ground adjacent to each other, some of the rods projecting from the ground at an angle relative to others of the rods; (b) providing a frame pipe extending between the adjacent rods of each pair of rods; (c) affixing a rod clamp assembly to each rod of a respective pair of rods by extending said rod through a bore in said rod clamp assembly and securing said rod clamp assembly to said rod; and (d) affixing a clamp plate for each rod of a respective pair of rods such that the two clamp plates are positioned on opposite sides of the frame pipe, and a bolt of each rod clamp assembly extends through holes in the two clamp plates and affixes the two rod clamp assemblies and two clamp plates together.

[0031] Further aspects of the invention and features of specific embodiments of the invention are described below.

[0032] Brief Description of the Drawings

[0033] The accompanying drawings illustrate non-limiting example embodiments of the invention.

[0034] Figure 1 is a schematic side view of the foundation assembly according to one embodiment of the invention.

[0035] Figure 2 is a close-up view of a portion of the foundation assembly of Figure 1 .

[0036] Figure 3 is an exploded view of the clamping structure. Figure 4 is an assembled view of the clamping structure of Figure 3.

[0037] Figure 5A is a top plan view of a foundation assembly according to an embodiment of the invention.

[0038] Figures 5B to 5E are schematic diagrams of example embodiments of the foundation assembly.

[0039] Figure 6A and 6B are elevation and perspective views, respectively, of a load point adapter for attaching infrastructure to the foundation assembly.

[0040] Figure 7 is a schematic diagram of an example embodiment of the foundation assembly installed on bedrock.

[0041] Figure 8 is a schematic diagram of an example embodiment of the foundation assembly installed in a swamp.

[0042] Detailed Description

[0043] Referring first to Figures 1 to 4, in one embodiment the foundation assembly 10 for supporting infrastructure has as its basic components rods 12, frame pipes 14, rod clamp assemblies 16 and clamp plates 18.

[0044] The rods 12 (also referred to herein as “piles”) are driven into the ground 20 such that their upper ends project above the ground. They are arranged in pairs, the pairs being spaced apart along the length of the frame pipe 14. The rods in each pair are on opposite sides of the frame pipe.

[0045] Examples of suitable rods are ones made of iron or steel, having a relatively small diameter, for example1 / 2 inch, % inch or 1 inch, depending upon the application and the weight of the infrastructure to be supported. The rods 12 may be driven into the ground at various angles to each other or may be approximately parallel. They can be hand driven with a sledge hammer. The location of the rods and the angle of installation is determined by the installer at the time of installation. Some rods are driven in at an angle to provide the required lateral stability to the foundation assembly, and to create symmetry in its structural capacity. If a rod 12 hits a rock 21 as it is being driven, the installer can leave it to rest on the obstruction and cut off the excess rod length above the rod clamp assembly. Alternatively, the installer may pull out the rod and reinsert it an a different angle to avoid the rock.

[0046] The frame pipes 14 may be any suitable elongated member having a size and strength appropriate for the application. In one embodiment, they may be iron pipes having a diameter of about 5 inches and a wall thickness of about % inch.

[0047] The rods 12 are affixed to the frame pipes 14 by means of the rod clamp assemblies 16 and the clamp plates 18.

[0048] A rod clamp assembly 16 comprises a pipe section 22 and a bolt 24. The pipe section has a bore 26 which receives a rod 12. The diameter of the bore may be, for example, about 1 inch. The rod clamp assembly has two rod fastening bolts 28 arranged to be tightened to press against the rod 12 and affix it in the bore 26 in the pipe section 22 of the rod clamp assembly. The bolt 24 extends perpendicularly from the back of the pipe section 22. It has a length sufficient to extend to the opposite side of the frame pipe, for example a length of about 6 inches. It has a threaded end 30 to receive a washer 32 and nut 33.

[0049] The clamp plates 18 are rectangular plates having two holes 34 for receiving the bolts 24 of the rod clamp assemblies 16. In one embodiment, the clamp plates may, for example, be steel plates having a thickness of about 3 / 8 inch, a width of about 5 inches, a length of about 8 inches, with holes 34 having a diameter of % inch and each being about 1 .5 inches from a respective end of the plate.

[0050] Referring to Figures 3 and 4, a pair of adjacent rods 12A, 12B is affixed to the frame pipe 14 as follows. A rod clamp assembly 16A is fitted over the rod 12A with the rod 12A extending through the bore 26A and the bolt 24A of the rod clamp assembly 16A extending through the lower hole 34A of the clamp plate 18A. The rod fastening bolts 28A of the rod clamp assembly 16A are tightened to secure the rod 12A to the rod clamp assembly 16A.

[0051] A second rod clamp assembly 16B is fitted over the rod 12B on the opposite side of the frame pipe 14, with the rod 12B extending through the bore 26B of the rod clamp assembly 16B, and the bolt 24B of the rod clamp assembly 16B extending through the upper hole 34B of the clamp plate 18B. The rod fastening bolts 28B of the rod clamp assembly 16B are tightened to secure the rod 12B to the rod clamp assembly 16B.

[0052] The frame pipe 14 is positioned between the two bolts 24A, 24B. The bolt 24A of the rod clamp assembly 16A extends through the lower hole 34B in the clamp plate 18B and is locked in place with the washer 32A and nut 33A. The bolt 24B of the rod clamp assembly 16B extends through the upper hole 34A in the clamp plate 18A and is locked in place with the washer 32B and nut 33B. The frame pipe 14 is accordingly held securely between the two clamp plates 18A, 18B and between the two bolts 24A, 24B. Successive spaced apart pairs of rods 12 are affixed to the frame pipe 14 in the same manner, securing the frame pipe along its length. The frame pipe is typically set close to and parallel to the ground, though installation over water or above vegetation may require the frame pipe to be set higher above the ground, and the use of rods 12 of longer length. Some example lengths for the rods are in the range of about 5 to 15 feet, depending upon the conditions of particular installations.

[0053] The foundation assembly 10 may have various arrangements of secured frame pipes, depending upon the terrain and the infrastructure to be supported. Referring to Figure 5A, in one embodiment the foundation assembly 10 comprises four frame pipes 14 in a rectangular configuration. At the corners of the foundation assembly, one frame pipe 14 is supported on the adjacent frame pipe 14, and the two frame pipes are affixed together by means of upper and lower clamp plates 18 bolted together by bolts 36 (as best seen in Figure 1 ). Other embodiments of the foundation assembly, with the frame pipes in various configurations, are schematically depicted in Figures 5B to 5E. An installation on sloping ground 20 is depicted in Figure 5E.

[0054] Load points 38 are the positions on the installed frame pipes 14 that the user chooses for loading the infrastructure onto the foundation assembly 10. The choice will depend upon the arrangement of the frame pipes, the terrain and the infrastructure to be supported. In some embodiments the load points 38 support infrastructure such as a street light, signage and telecom towers. In some embodiments, a load point adaptor 40 is used to facilitate attachment of the infrastructure to the foundation assembly. Referring to Figures 6A and 6B, a load point adaptor 40 comprises a yoke 42 shaped to fit over a frame pipe 14, a top plate 44, and a U-bolt 46 extending around the frame pipe and bolting the yoke and top plate to the frame pipe. The infrastructure is then bolted to the top plates of one or more load point adaptors. Load points 38 in example embodiments of the foundation assembly 10 are depicted in Figures 5A to 5E, showing the frame pipes 14, the pairs 48 of rod clamp assemblies and clamp plates, and the load points 38.

[0055] In some embodiments of the foundation assembly, useful for example for installation where the ground comprises bedrock, the rods are placed into the ground by drilling holes in the bedrock and affixing the rods in the holes. Referring to Figure 7, small diameter holes 50 are drilled into the bedrock 52, for example by means of a hammer drill. The rods 12 are inserted into the holes 50 and are secured with grout, epoxy or other adhesive. The frame pipes 14 are then affixed to the rods 12 as described above.

[0056] Figure 8 depicts an embodiment of the foundation assembly installed in a swampy area. The rods 12 are driven into the ground 20 under the water 54, i.e., into the bottom of the swamp. The frame pipes 14 are then affixed to the rods above the water level. No work needs to be done under the water surface.

[0057] In the foregoing description, where a component (e.g. an assembly, device, etc.) is referred to, unless otherwise indicated, reference to that component (including reference to a means) should be interpreted as including as equivalents of that component any component which performs the same function as the described component, including components which are not structurally equivalent to the disclosed structures which perform the function in the illustrated exemplary embodiments of the invention.

[0058] Throughout the foregoing description and the drawings, in which corresponding and like parts are identified by the same reference characters, specific details have been set forth in order to provide a more thorough understanding to persons skilled in the art. However, well known elements may not have been shown or described in detail to avoid unnecessarily obscuring the disclosure. Accordingly, the description and drawings are to be regarded in an illustrative, rather than a restrictive, sense.

[0059] As will be apparent to those skilled in the art in the light of the foregoing disclosure, many alterations and modifications are possible in the practice of this invention without departing from the scope thereof. Accordingly, the scope of the invention is to be construed in accordance with the following claims.

Claims

Claims1 . A foundation assembly (10) for supporting infrastructure, comprising:(a) a plurality of spaced apart pairs of rods (12) installed in the ground such that the upper ends of the rods of a respective pair project above the ground adjacent to each other, some of the rods projecting from the ground at an angle relative to others of the rods;(b) a frame pipe (14) extending between the adjacent rods of each pair of rods;(c) means for affixing the frame pipe to the rods, comprising:(i) a plurality of rod clamp assemblies (16), each being affixed to a respective rod that extends through a bore (26) in the rod clamp assembly (16), each rod clamp assembly having a bolt (24);(ii) a plurality of clamp plates (18), each having holes (34) for passage of the bolts (24) of two rod clamp assemblies; wherein the rods of an adjacent pair of rods are affixed to the frame pipe (14) by means of two rod clamp assemblies (16) and two clamp plates (18).

2. The foundation assembly according to claim 1 , wherein, for each adjacent pair of rods, one rod clamp assembly (16) and one clamp plate (18) are positioned on one side of the frame pipe (14) and a second rod clamp assembly and second clamp plate are positioned on the opposite of the frame pipe, the two rod clamp assemblies and two clamp plates being affixed together by the bolts (24) of the two rod clamp assemblies.

3. The foundation assembly according to claim 1 or 2, wherein the foundation assembly comprises two or more frame pipes (14) affixed to spaced apart pairs of rods, the frame pipes being arranged in a generally rectangular configuration.

4. The foundation assembly according to any one of claims 1 to 3, wherein the foundation assembly comprises two or more frame pipes (14) affixed to spaced apart pairs of rods, the frame pipes being arranged at an angle to each other.

5. The foundation assembly according to any one of claims 1 to 4, further comprising a plurality of load points (38) for loading the infrastructure onto the foundation assembly.

6. The foundation assembly according to claim 5, further comprising a load point adaptor (40) affixed to a frame pipe at each load point.

7. The foundation assembly according to any one of claims 1 to 6, wherein the rods (12) are installed in the ground by driving them into the ground.

8. The foundation assembly according to any one of claims 1 to 6, wherein the rods (12) are installed in the ground by drilling holes (50) in the ground and inserting the rods into the holes and securing them therein.

9. The foundation assembly of claim 8, wherein the rods are secured in the holes (50) by means of grout, epoxy or other adhesive.

10. A method of making a foundation assembly (10) for supporting infrastructure, comprising the steps of:(a) installing a plurality of spaced apart pairs of rods (12) in the ground such that the upper ends of the rods of a respective pair project above the ground adjacent to each other, some of the rods projecting from the ground at an angle relative to others of the rods;(b) providing a frame pipe (14) extending between the adjacent rods of each pair of rods;(c) affixing a rod clamp assembly (16) to each rod (12) of a respective pair of rods by extending said rod through a bore (26) in said rod clamp assembly (16) and securing said rod clamp assembly to said rod; and(d) affixing a clamp plate (18) for each rod (12) of a respective pair of rods such that the two clamp plates are positioned on opposite sides of the frame pipe, and a bolt (24) of each rod clamp assembly (16) extends through holes (34) in the two clamp plates and affixes the two rod clamp assemblies and two clamp plates together.11 . The method according to claim 10, wherein the rods (12) are installed in the ground by driving them into the ground.

12. The method according to claim 10, wherein the rods (12) are installed in the ground by drilling holes (50) in the ground and inserting the rods into the holes and securing them therein.

13. The method according to claim 12, wherein the rods are secured in the holes (50) by means of grout, epoxy or other adhesive.

14. The method according to any one of claims 10 to 13, wherein the rods (12) are installed at locations and at angles selected by the installer at the time of installation.

15. The method according to any one of claims 10 to 13, wherein the installer selects the number of rods to achieve the required structural capacity and stability.

16. The method according to any one of claims 10 to 13, wherein the installer selects load points (38) on the frame pipe.

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