AU2016102394A4 - A method of constructing a column, a subterranean structure, and a structure made from the method - Google Patents

Abstract

Abstract The present invention provides a method of constructing a subterranean structure (11) and a column (19) used for same. The method comprises the steps of installing at least one retaining wall (15), creating at least one hole (18) and forming the column (19) therein, forming a slab (17) supported by the at least one retaining wall and the at least one column. An access way is formed when forming the slab to provide access under the slab. The method further comprises the step of excavating under the slab to provide the subterranean structure. 4 g4 E Figure 8

Description

A method of constructing a column, a subterranean structure, and a structure made from the method.

TECHNICAL FIELD [0001] The present invention generally relates to a method of constructing a subterranean structure, such as a basement of a building, and a structure made from same.

BACKGROUND ART [0002] Conventionally, buildings with underground basements are built by a bottom-up method where sub-structure and super-structure floors are constructed sequentially from the bottom of the sub-structure or lowest level of basement to the top of the superstructure. This form of construction typically first requires the excavation of a large pit to a depth equal to where the lowermost part of the structure. In order to construct the pit and to provide access for various services, this form of construction requires a much larger construction footprint than the footprint of the intended structure. This form of construction is therefore problematic in built up areas. Alternatively, prior to construction piles or diaphragm walls may be driven through the soil to retain the surrounding earth and allow for excavation of the soil so the lower levels may be constructed. While this does not require as large a footprint, it does require the walls or piles to be anchored or propped as excavation to the lowermost part of the building proceeds.

[0003] For those structures having significant site constraints and a limited construction window, an alternative form of construction is a top-down construction method. This method builds the permanent structure members of the basement from the top to the bottom, excavating each level as the structure is completed. The top/down method is advantageous for deep excavation projects where tieback installation is not feasible and soil movements must be minimised.

[0004] Top down construction method also provide a method for constructing deep excavations, where multiple basement floors are constructed as the excavation progresses.

2016102394 27 Oct 2016 [0005] Top-down construction begins with retaining wall installation and then loadbearing elements that will carry the future super-structure. The basement columns (typically steel l-sections column/piles) which are constructed before any excavation takes place and rest on the load bearing elements. These load bearing elements are typically concrete barrettes constructed under slurry.

[0006] In top down construction, retaining walls are constructed first to support the later excavation. Eventually the retaining walls form the final external structural walls of the basement. From the ground level, permanent piles (typically steel beams) are installed internally between the soil retaining walls to reduce the span of future floors. The ground floor slab is cast on the unexcavated soil and tied into the walls. Once the ground floor slab is in place, construction of the building superstructure can then commence before or during excavation of the soil underneath the ground floor slab. The remainder of the excavation is completed under the protection of the floor slab. Upon completion of the excavation, the basement floor or floors are completed and the services and finishes are installed within the completed sub-structure. Top down construction dispenses with the requirement to first excavate a below-ground pit prior to commencement of construction. It also dispenses with the need for the bulk of the formwork otherwise required for the suspended ground floor, suspended basement floors, columns and retaining walls.

[0007] The top down method of construction is designed to enable above ground construction work to be carried out simultaneously with the excavation of the basement(s) resulting in significant saving of time and cost on a project.

[0008] Top-Down construction greatly reduces the likelihood of damage to adjoining buildings otherwise associated with soil movement as before excavation proceeds the basement walls are propped by the floor slabs. This eliminates the need for sheet piling or any other form of temporary propping. In addition, dewatering is not required, so there is no associated subsidence. These advantages make top down construction ideal for construction in congested areas.

[0009] Furthermore, as top down construction allows provides progressive propping of the basement perimeter retaining walls, the walls are not required to be as thick.

2016102394 27 Oct 2016 [0010] While top-down construction has many advantages, the construction method does present several disadvantages. For instance, the construction method presents limited space and restricted access for excavation and construction of the floor below. This also presents the need for additional ventilation in order to vent fumes from machinery to ensure a safe working environment.

[0011] With top-down constructions, as the exterior walls and/or centre columns or cast directly in the soil there is the risk that the exterior walls and/or centre columns exceed specified installation tolerances and impact the interior space. As excavation occurs after the sub-structure is formed the accuracy of the wall/columns and their position is unknown during the construction process. If the walls and/or columns are incorrectly orientated and/or incorrectly positioned then additional work may be required to the wall/columns after excavation. Furthermore, if a wall/column is not plumb, or not positioned correctly then the space adjacent the wall/column may no longer be usable for its intended purpose. For instance, where the sub-structure is to provide a basement car park, a tilted column may result in several car bays not being able to be used.

[0012] With any subterranean structure the potential for water leakage through the substructure is also problematic. As the installation is conducted without excavating the surrounding soil it is not possible to install external waterproofing on the outside of the retaining/external walls.

[0013] The preceding discussion of the background art is intended to facilitate an understanding of the present invention only. The discussion is not an acknowledgement or admission that any of the material referred to is or was part of the common general knowledge as at the priority date of the application.

SUMMARY OF INVENTION [0014] It is an object of this invention to provide a method of constructing a subterranean structure which ameliorates, mitigates or overcomes, at least one disadvantage of the prior art, or which will at least provide an alternative and practical choice.

2016102394 27 Oct 2016 [0015] The present invention provides a method of casting a column in soil, the method comprises:

creating a hole in the soil;

filling the hole with a settable liquid;

lowering an elongate assembly into the hole wherein the elongate assembly is supported such that the elongate assembly is lowered in a substantially vertical orientation;

adjusting the elongate assembly once received in the hole so that the elongate assembly is substantially vertical;

excavating the soil once the settable liquid has set to provide the column.

[0016] The present invention provides a method of casting a column in soil, the method comprises:

creating a hole in the soil;

filling the hole with a settable liquid;

lowering an elongate assembly into the hole wherein the elongate assembly is supported such that an elongate element is lowered in a substantially vertical orientation;

adjusting the elongate assembly once received in the hole so that the elongate assembly is substantially vertical;

excavating the soil once the settable liquid has set to provide the column.

[0017] The method may comprise the step of casting/installing a guide means at the surface to assist in guiding an auger to form the hole.

[0018] The method may comprise the step of filling the hole with the settable liquid as the hole is created.

[0019] The method may comprise the step of layering an outside surface of a hollow pipe of the elongate assembly with a protective layer, whereupon excavation, the

2016102394 27 Oct 2016 protective layer may be removed from the hollow pipe, wherein the outer surface of the hollow pipe provides the finished surface of the column.

[0020] The method may comprise the step of securing one or more shear connectors to the elongate element wherein the one or more shear connectors are substantially 90° thereto.

[0021] The present invention further provides a column for supporting a structure, the column having a first portion embedded in the ground, and an exposed second portion between the first portion and the structure, the column comprises an elongate assembly cast in a material formed from a settable material, such as concrete, and a plurality of shear connectors extending from the elongate assembly, wherein the elongate assembly comprises:

a hollow pipe, an outer surface of which provides the exposed surface of the column after excavation;

a reinforcing portion secured relative to the hollow pipe, the reinforcing portion extending downwardly from the bottom of the hollow pipe;

an elongate element secured to the hollow pipe and extending upwardly from the top of the hollow pipe.

[0022] Preferably the outer surface of the hollow pipe is pre-treated to achieve an aesthetically acceptable finish.

[0023] Preferably the reinforcing portion extending at least partially through the hollow pipe.

[0024] The column may comprise a third portion adjacent the second portion. The third portion is adapted to be incorporated within the structure to be supported by the column, such as a slab.

[0025] The column may comprise a fourth portion adjacent the third portion. An upper portion of the elongate element may provide the fourth portion.

[0026] Preferably the column is cast using the aforementioned method.

2016102394 27 Oct 2016 [0027] The shear connectors may be in the form of one or a combination of the following: shear studs, bars, beams, plates.

[0028] The shear connectors may be secured to the third portion so that in use the shear connectors are embedded in the structure.

[0029] The shear connectors may be secured to at least part of the elongate element wherein they provide a shear connector between the elongate element and the settable material.

[0030] In one aspect of the invention the hollow pipe extends along the second portion of the column.

[0031] In another aspect of the invention at least part of the hollow pipe extends along the second portion of the column.

[0032] In another aspect of the invention the hollow pipe extends along at least part of the second portion of the column.

[0033] The upper end of the second portion may support a collar. The collar takes part of the load from the structure the column is supporting (e.g. slab) so that the settable material is exposed to less stress.

[0034] Preferably the upper portion of the elongate element extends upwardly from the top of the hollow pipe.

[0035] The upper portion of the elongate element may extend above the settable material. A further column, elongate element, or other structure may be secured to the upper portion of the elongate element.

[0036] The elongate element may extend through the hollow pipe to extend from both the bottom and the top of the hollow pipe.

[0037] The column may further comprise a reinforcement assembly comprising a reinforcement portion and a plurality of reinforcement connections for connecting the reinforcement portion to the hollow pipe, and/or to the elongate element.

[0038] The reinforcing portion of the elongate assembly may have an end region which terminates in the first portion of the column.

2016102394 27 Oct 2016 [0039] The reinforcement connections may be in the form of a plurality of bars welded to the hollow pipe and extending downwardly therefrom. The reinforcing portion may be welded to the bars.

[0040] The reinforcing portion may extend through the hollow pipe from the top of the hollow pipe.

[0041] The reinforcing portion may be flexible to accommodate any curvature in the hole as the reinforcing portion is positioned in the hole.

[0042] In one aspect of the invention an end region of the first portion may have an enlarged diameter.

[0043] In another aspect of the invention an end region of the first portion may be supported on a support.

[0044] A footing may be provided between the first portion and the second portion.

[0045] Shear connectors may be secured to the hollow pipe wherein they provide a shear connector between the hollow pipe and the footing.

[0046] The column may comprise an expansion means to prevent the column from being damaged during a fire. The expansion means may comprise a plurality of holes in the collar.

[0047] When the column is used to support a number of subterranean floors, the column may comprise the first portion, the fourth portion and one or more pairs of second portion and third portion therebetween. The number of pairs of second portion and third portion will be dictated by the number of subterranean floors.

[0048] The present invention provides a method of constructing a subterranean structure comprising the steps of:

installing retaining walls along the perimeter of the proposed subterranean structure;

creating a plurality of holes and forming columns therein, the holes being spaced between the retaining walls;

2016102394 27 Oct 2016 forming a slab supported by the ground, retaining walls and the plurality of columns;

excavating under the slab;

wherein after excavation is complete the subterranean structure is provided.

[0049] The method may comprise the step of laying a thick flexible sheet material, such as polyethylene, on the ground before casting the slab. This ensures the underside of the slab (which will provide the roof of the subterranean structure) is aesthetically acceptable. The polyethylene material may be 11 mm in thickness.

[0050] The subterranean structure may be a basement carpark or other basement structure.

[0051] The method may comprise the step of establishing an access way to access the area under the slab when forming the slab. The access way may be formed in the slab as the slab is formed. The access way may be provided through the retaining wall.

[0052] Preferably, the method further comprises the step of finishing the subterranean structure to provide the basement car park or other basement structure. Finishing the subterranean structure may further comprise one or more of the following steps: casting a floor to be subsequently suspended to the basement on a temporarily levelled prepared ground, installing services such as power and water.

[0053] The method may repeat the aforementioned method to construct one or more further subterranean structures thereunder.

[0054] Each of the plurality of holes may be created by drilling the soil with a continuous auger.

[0055] Preferably each hole is filled with a settable fluid as the auger is removed therefrom.

[0056] Each column may be cast according to the aforementioned method.

[0057] The present invention further provides a method of constructing a subterranean structure comprising the steps of:

2016102394 27 Oct 2016 installing at least one retaining wall;

creating at least one hole and forming a column therein;

forming a slab supported by the at least one retaining wall the at least one column;

when forming the slab forming an access way for access under the slab;

excavating under the slab;

wherein after excavation is complete the subterranean structure is provided.

BRIEF DESCRIPTION OF THE DRAWINGS [0058] Further features of the present invention are more fully described in the following description of several non-limiting embodiments thereof. This description is included solely for the purposes of exemplifying the present invention. It should not be understood as a restriction on the broad summary, disclosure or description of the invention as set out above. The description will be made with reference to the accompanying drawings in which:

Figure 1 is a cross section of a guide for use in forming a hole for constructing a column of a basement according to a first embodiment of the present invention;

Figure 2 is a cross section of the hole of figure 1 formed and having a settable material therein;

Figure 3 is a cross sectional view of a column formed in the hole of figure 2,

Figure 4 is a view of an alternative column without a reinforcing cage;

Figure 5 is a cross sectional view of a first portion and second portion of the column in figure 4 with the reinforcing cage included,

Figure 6 is a cross sectional view of a further alternative column formed in the hole of figure 2,

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Figure 7 is a cross sectional view of yet a further alternative column formed in the hole of figure 2,

Figure 8 is a schematic cross sectional view of one side of the basement.

[0059] In the drawings like structures are referred to by like numerals throughout the several views. The drawings shown are not necessarily to scale, with emphasis instead generally being placed upon illustrating the principles of the present invention.

DESCRIPTION OF EMBODIMENTS [0060] The present invention, according to a first embodiment of the invention is directed to a subterranean structure being a basement 11 of a building, and a method of constructing the basement 11. The method of construction involves the installation of a retaining wall 15 around/along the perimeter of the proposed building, and the casting of a plurality of columns 19 within the confines of the space between the retaining walls

15. Once the walls 15 and columns 19 are cast a slab 17 may be poured whereby the slab 17 is supported by the ground, the retaining walls 15 and the columns 19.

[0061] The top down construction method of creating the basement is particularly advantageous in congested areas but also delivers a finished building in a shorter period of time when compared to traditional building methods. The present invention seeks to improve upon this by providing an improved method of constructing a building based on the top down method. This is partly achieved by casting the columns 19 in a manner which largely negates the need to further dress the columns 19 once the subterranean levels have been excavated. The method of casting the columns 19 also greatly improves the accuracy of the vertical orientation of each column 19. By increasing the predictability of the columns angle and their orientation, the retaining walls 15 and columns 19 do not need to be designed to accommodate excessive inaccuracies, [0062] The retaining walls 15 are in the form of a diaphragm wall. However, other types of suitable wall constructions can also be used. Each diaphragm retaining wall 15 is constructed by first digging a trench, wherein the trench is filled with an engineered fluid, such as bentonite. Once the trench is constructed a mesh panel is inserted and

2016102394 27 Oct 2016 the trench filled with concrete, displacing the engineered fluid. The concrete then sets to provide the retaining walls 15 [0063] The basement 11 incorporates a plurality of columns 19 which are spaced within the confines of the retaining walls 15. The columns 19 are designed to be cast in positions which have minimal impact on the basement 11. For instance, where the basement will be used as a car park the columns are positioned between car bays to ensure the basement is able to hold as many car bays as possible for the given space, [0064] Referring to figures 1 to 3, each column 19 is cast by forming a hole 18 through the surface 13 using a continuous auger (not shown). To assist in forming the hole 18 a guide 20 is cast around the periphery of the proposed hole 18. The guide 20 adds stability to the auger during the drilling process and ensures the auger maintains the desired drilling direction.

[0065] As the hole 18 is formed the hole is filled with a settable material 21 which helps maintains the integrity of the hole during the drilling process. Upon extraction of the auger the hole 18 remains filled with the settable material, as shown in figure 2.

[0066] Once the auger is extracted an elongate assembly 23 is lowered into the hole 18. The elongate assembly 23 is suspended from a crane or similar lifting device (not shown) such that the elongate assembly 23 is maintained in a substantially vertical orientation. Maintaining the elongate assembly 23 in a substantially vertical orientation will ensure the resulting column 19 is within the specified tolerances for such construction.

[0067] To ensure that the elongate assembly 23 is able to be inserted as a vertical assembly, the hole 18 is larger in diameter than the elongate assembly 23. This will also allow the orientation of the elongate assembly 23 to be adjusted once inserted in the hole, as discussed below.

[0068] The elongate assembly 23 comprises a hollow pipe 25, the outer surface 27 of which will provide the exposed surface of the column 19 after excavation of the basement 11.

[0069] As shown in figure 3, the elongate assembly 23 comprises a reinforcing portion in the form of a reinforcement cage 29. The reinforcement cage 29 is secured relative to

2016102394 27 Oct 2016 the hollow pipe 25, such that it extends downwardly from the bottom of the hollow pipe 25. A plurality of rods/bars 30 are secured to the end of the hollow pipe 25 allowing the reinforcement cage 29 to be readily secured relative to the hollow pipe 25.

[0070] The elongate assembly 23 also comprises an elongate element 31 secured relative to the hollow pipe 25 such that it extends upwardly from the top of the hollow pipe 25. The elongate element 31 extending above the hollow pipe 25 supports a shear connector in the form of a beam 33. Once the slab is poured the beam 33 will be embedded therein.

[0071] The elongate element 31 allows the vertical orientation of the elongate assembly 23 to be adjusted once the elongate assembly 31 is received in the hole. This is a further measure to ensure the vertical orientation of the column is within the specified tolerances.

[0072] Prior to inserting the elongate assembly 23 in the hole, the hollow pipe 25 is wrapped in a protective layer for reasons which will be described below.

[0073] In a variation of the process, the reinforcement cage 29 may not necessarily be connected to the hollow pipe prior to lowering the elongate assembly 23 into the hole. The reinforcement cage 29 may be lowered into the hole and supported adjacent the hole opening. The hollow pipe 25 can then be positioned thereover and the reinforcement cage 29 secured to the hollow pipe 25 before the reinforcement cage is further lowered into the hole.

[0074] Once the column 19 is cast the column of the present embodiment will comprise a first portion 61, a second portion 63, a third portion 65 and a fourth portion 67.

[0075] The first portion 61 is embedded in the ground and can have an enlarged end 71, as shown in figure 3 for providing more support, or may be of relatively uniform diameter, as shown in alternative columns in figures 5, 6 and 7. The reinforcement cage 29 of the elongate assembly 23 has an end region 73 which terminates in the first portion of the column.

[0076] The second portion 63 extends from the first portion 61 to the basement roof 35.

The second portion 63 incorporates the hollow pipe 25 which, in this embodiment, extends along the second portion. After excavation is complete and the protective coat

2016102394 27 Oct 2016 removed, the outer surface 27 of the hollow pipe 25 is exposed to provide the finished surface of the column.

[0077] The upper end of the second portion 63 supports a collar 75. The collar 75 distributes the load from the structure the column 19.

[0078] As an alternative, or in addition to the enlarged ends of the first portion 61, a footing 83 can be provided between the first portion 61 and the second portion 63, as shown in figure 5. In this arrangement additional shear connectors in the form of studs 133 are secured to the hollow pipe 25 and are embedded in the footing 83 once poured.

[0079] The third portion 65 is adjacent the second portion 63. The third portion 65 is incorporated within the basement roof 35. The third portion supports the shear connector beam 33.

[0080] The fourth portion 67 is adjacent the third portion and extends above the basement roof 35. An upper portion 77 of the elongate element 31 provides the fourth portion 67. As shown in figure 3 and 4 the fourth portion 67 provides an anchor/support for a part of the structure being built above the basement floor 35. For example, a wall/ column 79 of the superstructure may be formed around the fourth portion 67.

[0081] The elongate element 31 can be a unitary beam which extends from the first portion 61 to the fourth portion 67, as shown in figure 4, or which extends from the second portion 63 to the fourth portion 67, as shown in figure 3. Alternatively the elongate element 31 comprises two beams 31a, 31b wherein the two beams are secured together at a flange 81 which, once cast, is embedded in the basement roof 35, as shown in figures 6 and 7.

[0082] The basement also comprises a slab which provides the basement roof 35. The basement roof 35 may be formed once the retaining walls 15 and columns 19 are cast. In order to form the basement roof 35 the ground is first prepared. The basement roof 35 can then be formed whereby it is supported by the retaining walls 15, the columns 19 and the ground. As the slab, which provides the basement roof 35 as well as the floor of the ground level of the building, is supported by the ground the slab only needs to be designed to support the loads it will be exposed to in normal service. In traditionally construction methods the slab must be poured as a suspended slab and would need to be temporarily supported by formwork during construction. As construction loads are

2016102394 27 Oct 2016 often much greater than the service loads the slab is designed to be much thicker than actually required during normal service. The present method allows the slab to be designed to support normal service loads only, allowing the slab to be thinner.

[0083] Once the basement roof 35 is completed, construction of the superstructure can commence. As the ground floor is already formed construction vehicles can access central parts of the building eliminating the need for large construction vehicles and machinery such as cranes.

[0084] Once the basement roof 35 is complete it is also possible to commence excavation of the soil between the retaining walls 15. Once the basement is excavated, the basement floor 36 is formed or construction of lower basement floors may begin. These lower floors may be made using the same technique discussed above.

[0085] Once excavation is complete, the protective layer around the hollow pipe 25 can be removed. This removes the settable material which has adhered to the side of the hollow pipe 25, and provides a clean, finished surface of the column 19, negating the need for the columns 19 to undergo any further treatment. With prior methods, the columns require extensive work after the excavation is complete to provide a column having a surface which is aesthetically acceptable. In the event that the column is not vertical, as occurs in prior methods, the finish will need to be applied to the column so that the column appears as though it is vertically orientated.

[0086] As the process of casting the columns ensures the columns are substantially vertical, the basement does not require any further strengthening otherwise required if the columns were not correctly orientated, as can be the case with prior art methods of construction.. According to other top down construction methods it is not possible to ensure the columns are formed vertically. Where the columns are not correctly orientated the load capacity of these columns can be reduced. In these scenarios additional beams and/or columns are required to support the basement. This not only adds cost to the process but can also limit the expected utility/capacity of the basement.

[0087] In some instances the basements will be at a level where water may seep into the basement. In these instances a cavity 47 is formed, as shown in figure 8. During construction of the basement a separate wall 45 is formed adjacent the retaining walls

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15, and a drain 49 is positioned in the basement floor 36. This forms the cavity 47, providing a means to allow water to be drained away.

[0088] With this form of construction the effect to the local area and nearby buildings is greatly diminished. Furthermore, as excavation is contained the amount of dust and noise is reduced significantly.

[0089] As would be understood by those skilled in the art the shear connectors may take any form. For example, the shear connectors may be in the form of beams secured to the column 19 and embedded in the basement roof 35, as shown in at least figure 3, studs secured to the column and embedded in the footing, as shown in figure 5, rods secured to the column and embedded in the settable material (not shown), or a combination of these.

[0090] As would be understood by those skilled in the art the hollow pipe can take any shape or configuration, for instance the pipe can be square or round, thick walled or narrow. Similarly the elongate element may take the form of any rigid beam like structure, such as an I-beam, and may be made from any suitable material.

[0091] Modifications and variations such as would be apparent to the skilled addressee are considered to fall within the scope of the present invention. The present invention is not to be limited in scope by any of the specific embodiments described herein. These embodiments are intended for the purpose of exemplification only. Functionally equivalent products, formulations and methods are clearly within the scope of the invention as described herein.

[0092] Reference to positional descriptions, such as lower and upper, are to be taken in context of the embodiments depicted in the figures, and are not to be taken as limiting the invention to the literal interpretation of the term but rather as would be understood by the skilled addressee.

[0093] While the invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

2016102394 27 Oct 2016 [0094] The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a”, “an” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The term “structure” includes part of a structure. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed.

Claims (41)

1. A method of casting a column in soil, the method comprises:

creating a hole in the soil;

filling the hole with a settable liquid;

lowering an elongate assembly into the hole wherein the elongate assembly is supported such that an elongate element is lowered in a substantially vertical orientation;

adjusting the elongate assembly once received in the hole so that the elongate assembly is substantially vertical;

excavating the soil once the settable liquid has set to provide the column.

2. The method according to claim 1 comprising the step of casting/installing a guide means at the surface to assist in guiding an auger to form the hole.

3. The method according to claim 1 or 2 comprising the step of filling the hole with the settable liquid as the hole is created.

4. The method according to claim 1, 2 or 3 comprising the step of layering an outside surface of a hollow pipe of the elongate assembly with a protective layer, whereupon excavation, the protective layer is removed from the hollow pipe, wherein the outer surface of the hollow pipe provides the finished surface of the column.

5. The method according to any one of the preceding claims comprising the step of securing one or more shear connectors to the elongate element wherein the one or more shear connectors are substantially 90° thereto.

2016102394 27 Oct 2016

6. A column for supporting a structure, the column having a first portion embedded in the ground, and an exposed second portion between the first portion and the structure, the column comprises an elongate assembly cast in a material formed from a settable material, such as concrete, and a plurality of shear connectors extending from the elongate assembly, wherein the elongate assembly comprises:

a hollow pipe, an outer surface of which provides the exposed surface of the column after excavation:

a reinforcing portion secured relative to the hollow pipe, the reinforcing portion extending downwardly from the bottom of the hollow pipe;

an elongate element secured to the hollow pipe and extending upwardly from the top of the hollow pipe.

7. The column according to claim 6 wherein the outer surface of the hollow pipe is pre-treated to achieve an aesthetically acceptable finish.

8. The column according to claim 6 or 7 wherein the reinforcing portion extends at least partially through the hollow pipe.

9. The column according to claim 6, 7 or 8 comprising a third portion adjacent the second portion, the third portion is adapted to be incorporated within the structure to be supported by the column.

10. The column according to any one of claims 6 to 9 comprising a fourth portion adjacent the third portion, an upper portion of the elongate element providing the fourth portion.

11. The column according to any one of claims 6 to 10 being manufactured according to the method as described in any one of claims 1 to 5.

12. The column according to any one of claims 6 to 11 wherein the shear connectors are in the form of one or a combination of the following: shear studs, bars, beams, plates.

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13. The column according io any one of claims 9 to 12 wherein the shear connectors are secured to the third portion so that in use the shear connectors are embedded in the structure.

14. The column according to any one of claims 6 to 13 wherein the shear connectors may be secured to at least part of the elongate element wherein they provide a shear connector between the elongate element and the settable material.

15. The column according to any one of claims 6 to 14 wherein the hollow pipe extends along the second portion of the column.

16. The column according to any one of claims 6 to 14 wherein at least part of the hollow pipe extends along the second portion of the column.

17. The column according to any one of claims 6 to 14 wherein the hollow pipe extends along at least part of the second portion of the column.

18. The column according to any one of claims 6 to 17 wherein the upper end of the second portion supports a collar.

19. The column according to any one of claims 9 to 18 wherein the upper portion of the elongate element extends upwardly from the top of the hollow pipe.

20. The column according to any one of claims 9 to 19 wherein the upper portion of the elongate element extends above the settable material.

21. The column according to any one of claims 9 to 20 wherein a further column, elongate element, or other structure is secured to the upper portion of the elongate element.

22. The column according to any one of claims 6 to 21 wherein the elongate element extends through the hollow pipe to extend from both the bottom and the top of the hollow pipe.

23. The column according to any one of claims 6 to 22 comprising a reinforcement assembly, the reinforcement assembly comprising a reinforcement portion and a plurality of reinforcement connections for connecting the reinforcement portion to the hollow pipe, and/or to the elongate element.

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24. The column according to claim 23 wherein the reinforcing portion of the elongate assembly has an end region which terminates in the first portion of the column.

25. The column according to claim 23 or 24 wherein the reinforcement connections is in the form of a plurality of bars welded to the hollow pipe and extending downwardly therefrom.

26. The column according to claim 25 wherein the reinforcing portion is welded to the bars.

27. The column according to any one of claims 23 to 26 wherein the reinforcing portion extends through the hollow pipe from the top of the hollow pipe.

28. The column according to any one of claims 23 to 27 wherein the reinforcing portion is flexible to accommodate any curvature in the hole as the reinforcing portion is positioned in the hole.

29. The column according to any one of claims 6 to 28 wherein an end region of the first portion has an enlarged diameter.

30. The column according to any one of claims 6 to 28 wherein an end region of the first portion is supported on a support.

31 .The column according to any one of claims 6 to 30 wherein a footing is provided between the first portion and the second portion.

32. The column according to claim 31 wherein shear connectors are secured to the hollow pipe wherein they provide a shear connector between the hollow pipe and the footing.

33. The column according to any one of claims 6 to 32 comprising an expansion means to prevent the column from being damaged during a fire.

34. The column according to any one of claims 10 to 33 when dependent on claim 9 the column comprises the first portion, the fourth portion and one or more pairs of second portion and third portion therebetween, the number of pairs of second portion and third portion will be determined by the number of subterranean floors.

2016102394 27 Oct 2016

35. A method of constructing a subterranean structure comprising the steps of:

installing retaining walls along the perimeter of the proposed subterranean structure;

creating a plurality of holes and forming columns therein, the holes being spaced between the retaining walls;

forming a slab supported by the ground, retaining walls and the plurality of columns;

excavating under the slab;

wherein after excavation is complete the subterranean structure is provided.

36. The method according to claim 35 comprising the step of laying a thick flexible sheet material on the ground before casting the slab.

37. The method according to claim 35 or 36 comprising the step of establishing an access way to access the area under the slab when forming the slab.

38. The method according to claim 37 wherein the access way is formed in the slab and/or is provided through the retaining wall.

39. The method according to any one of claims 35 to 38 comprising the step of finishing the subterranean structure to provide a basement car park or other basement structure.

40. The method according to claim 39 wherein finishing the subterranean structure further comprise one or more of the following steps: casting a floor to be subsequently suspended to the basement on a temporarily levelled prepared ground, installing services such as power and water.

2016102394 27 Oct 2016

41 .A method of constructing a subterranean structure comprising the steps of: installing at least one retaining wall;

creating at least one hole and forming a column therein;

forming a slab supported by the at least one retaining wall the at least one column;

when forming the slab forming an access way for access under the slab; excavating under the slab;

wherein after excavation is complete the subterranean structure is provided.