Apparatus and method for controlling liquid on a site

An apparatus, for allowing control of liquid level on a site, comprising a hollow stake body comprising lateral openings for allowing liquid thereinto when the apparatus is positioned into the ground, a stake tip at one end and a hit plate receiver at an opposite end. A method for controlling liquid level on an excavation site comprising positioning the apparatus at one location on the site, positioning a hit plate on the apparatus, repeatedly hitting the hit plate until at least one opening is below ground at a liquid control depth, removing the hit plate and installing a pump for pumping liquid accumulated in the apparatus. A mesh construction, for use with the apparatus, comprising a first punctured cover, a second punctured cover and a mesh assembly, comprising at least one filtration mesh, sandwiched between the first and the second punctured covers for allowing liquid therethrough.

TECHNICAL FIELD

The present invention relates to controlling liquid accumulation on a site and, more particularly, to controlling liquid accumulation on a site during excavation.

BACKGROUND

Under certain regulations, excavations may only be performed where an appropriate dewatering system has been installed (e.g., when digging below the water table). For instance, it may be necessary to lower and maintain the ground water elevation at a minimum of 0.6 meters (two feet) below the base of the excavation. Extracting water or liquid from a site may also be relevant when a spilling occurred (e.g., resulting in contamination of the site).

In other contexts, water or liquid may be accumulated in a stockpile site.

The present invention provides a solution that is meant to allow for controlling liquid on a site.

SUMMARY

A first aspect of the present invention is directed to an apparatus for allowing control of liquid level on a site comprising a hollow stake body comprising a plurality of lateral openings permeable to liquid (e.g., allowing water or air in and out) when the apparatus is positioned into the ground, a stake tip at one end of the hollow stake body for facilitating insertion of the apparatus into the ground and a hit plate receiver at an opposite end of the hollow stake body.

The apparatus may comprise a hit plate, removably positioned over the hit plate receiver, for receiving repeated hits. The hit plate may be adapted to transfer force exerted thereon by repeated hits to the hollow stake body for forcing the apparatus into the ground at the site. Once the hit place is removed, the hollow stake body allows for a pump hose to be positioned therewithin for allowing liquid possibly accumulated in the hollow stake body to be pumped out. A pipe may be provided inside the hollow stake body for connecting the pump hose at an upper end.

The hollow stake body may be made of steel. The hit plate receiver may also be made of steel and may have a first end aligned with the opposite end of the hollow stake body. The hit plate receiver may present openings for providing additional weldable surface with the hollow stake body.

The hit plate receiver may be made of steel and may have a first end aligned with the opposite end of the hollow stake body. The first end of the hit plate receiver and the opposite end of the hollow stake body may be inwardly tapered to provide a welding channel.

The hit plate receiver may be made of steel and may have a first end aligned with the opposite end of the hollow stake body and the hit plate receiver, opposite to the opposite end of the hollow stake body, may be shaped such that the length of a weld seam therealong is longer than the perimeter of the hollow stake body near the second end.

The hollow stake body may be a polygonal prism and the hit plate receiver may partially cover bends in the hollow stake body along edges of the polygonal prism.

The hollow stake body may be a polygonal prism and each of the plurality of lateral openings may be positioned on one or more surfaces defined by the polygonal prism.

The plurality of lateral openings may be interspersed for limiting stress formation along the hollow stake body. The plurality of lateral openings may be positioned only towards the stake tip. The apparatus may also provide a liquid tight well point.

The plurality of lateral openings may comprise at least one type of mesh, which may optionally be sandwiched between an outward punctured cover and an inward punctured cover. The outward punctured cover may further comprise elongated apertures along a longitudinal axis of the hollow stake body.

The mesh type may, for instance be a 12×64 stainless steel mesh, a 80μ mesh or a 120μ mesh.

A second aspect of the present invention is directed to a method for controlling liquid level on an excavation site comprising a) positioning, at one location on the site, a first apparatus comprising a hollow stake body comprising a plurality of lateral openings permeable to liquid (e.g., allowing water or air in and out), a stake tip at one end of the hollow stake body and a hit plate receiver at an opposite end of the hollow stake body, b) positioning a first hit plate on the hit plate receiver of the first apparatus, c) repeatedly hitting the first hit plate until at least one of the plurality of lateral openings is below ground at a liquid control depth, d) removing the first hit plate from the first apparatus and e) installing a pump for pumping liquid accumulated in the hollow stake body of the first apparatus.

The method may further comprise f) excavating at the site, g) removing the pump from the first apparatus and h) repeating at least b) to e) for increasing the liquid control depth before resuming f).

The method may further comprise repeating at least a) to e) with at least one additional apparatus at at least one additional location along a perimeter within the excavation site.

A third aspect of the present invention is directed to a mesh construction for use with an apparatus for controlling liquid level on an site comprising a first punctured cover, a second punctured cover and a mesh assembly, comprising at least one filtration mesh, sandwiched between the first punctured cover and the second punctured cover permeable to liquid when the mesh construction installed on the apparatus is underground at the site.

The mesh assembly may further comprise a protective mesh over the infiltration mesh and the first punctured cover, the first punctured cover being outwardly positioned when the apparatus is underground at the site.

The first punctured cover may comprise elongated apertures along a longitudinal axis of the apparatus for protecting the mesh assembly when the apparatus is being put into the ground at the site. The mesh may be a 12×64 stainless steel mesh, a 80μ mesh or a 120μ mesh.

DETAILED DESCRIPTION

Embodiments of the present invention relate to an apparatus for allowing control of liquid level on a site, a method for controlling liquid level on an excavation site and a mesh construction for use with an apparatus for controlling liquid level on a site.

Reference is now made concurrently toFIGS. 1A to 7of the accompanying drawings in whichFIG. 1Ashows a perspective view of an exemplary apparatus for allowing control of liquid level on a site in accordance with teachings of the present invention. The apparatus100is suitable when the liquid is water. Skilled persons will appreciate that other liquids may also be controlled. For instance, and without limitation, the liquid may be a mix of water and a petroleum product in different concentration (oil, gas, diesel, mix of any of these, etc.) or the petroleum product itself. The apparatus100may provide different configuration depending on the intended use.

The apparatus100may also be used to control contaminated liquid accumulated due to, for example, soil contamination. Attention is now drawn toFIG. 1Ashowing a partially assembled perspective view of the exemplary apparatus100. The exemplary apparatus100comprises a hollow stake body120permeable to liquid (e.g., allowing water or air in and out of the hollow body120) through a plurality of openings150, when positioned into the ground, a stake tip110at one end of the hollow stake body120for facilitating insertion of the apparatus100into the ground and a hit plate receiver130at an opposite end of the hollow stake body120. The hit plate receiver130, in its simplest form, allows positioning of a hit plate140at the top and of the hollow body120and may be integrated into the hollow body120. The hit plate receiver130, when provided as an additional component, may further solidify the hollow body120of the exemplary apparatus100and increase its resistance to repeated hits. The hollow stake body120and the hit plate receiver130of the exemplary apparatus100may be made out of steel. The steel may be, for example, stainless, Hardox™ or Scandia™. Skilled persons will notice that the sort of steel may vary without departing from the teachings of the present invention. The hollow stake body120and the hit plate receiver130may instead be made of other materials capable of withstanding the force of repeated hits. For instance, cast iron or other metal alloys may be suitable in some embodiments. The hollow stake body120and the hit plate receiver130could be provided in a single material/piece or could be provided in multiple assembled elements joined together (e.g., welded) to withstand expected forces.

The exemplary apparatus100may also comprise a hit plate140, removably positioned over the hit plate receiver130for receiving repeated hits. The hit plate140is adapted to transfer force exerted thereon by repeated hits to the hollow stake body120for forcing the apparatus100into the ground at the site. Once the hit plate140is removed, the hollow stake body120allows for a pump hose to be positioned therewithin for allowing liquid possibly accumulated in the hollow stake body120to be pumped out (not shown). A skilled person will readily recognize that other means for inserting the exemplary apparatus100into the ground at an excavation site may be used aside for repeated hits, such as continuously applying longitudinal pressure to the exemplary apparatus100. In an alternate embodiment of the hit plate,140an opening (e.g., in the center thereof; not shown) may be provided to allow a hose of a pump (not shown) to reach the inside of the hollow stake body. The exemplary apparatus100may allow a submersible pump (not shown) to be installed directly within the hollow body120(e.g., after positioning of the apparatus100on the site or, if the pump is installed to resist and able to resist the repeated hits, before positioning of the apparatus100on the site). The pump may also be installed in an air tight (or liquid tight) manner, to actively draw liquid from the ground via the openings150in the hollow body120. For example, an additional sealing component (not shown) may be provided in the hollow body120between the uppermost opening(s) and the upper end of the hollow body120to allow the air tight pump installation. A skilled person in the art would readily recognize that such features would not affect the teachings of the present invention. In a preferred embodiment, the hit plate140is 3″ thick. Skilled persons will recognize that the thickness of the hit plate140may vary without departing from the teachings of the present invention. In an alternative embodiment, the liquid tight installation may also allow for the connection of multiple exemplary apparatuses100to a single pump for removal of accumulated liquid in the exemplary apparatuses100. The exemplary apparatus100may also be used as a well point.

When an air tight installation is provided, the pump may also be used in reverse compared to the previous example (or another more suitable pump may be used) to pump air into the exemplary apparatus100in order to send the pumped air into the surrounding ground through the openings150, e.g., in order to improve or accelerate the dry off of the ground. This exemplary embodiment is expected to be particularly useful when the apparatus100is used on a stockpile that would benefit from being dryer (e.g., before being transported elsewhere for disposal).

In a preferred embodiment, the length of the hollow stake body120is 132″ and the internal width of the hollow stake body120is 16″ 31/32. The external width, in other words the width calculated from opposite points on the outer surfaces of the hollow stake body120, is 18″ 15/32. Of course, skilled persons will notice that the dimensions of the apparatus100may vary without departing from the teachings of the present invention (i.e., the width, height or shape may differ). In an alternate embodiment of the apparatus, a smaller version of the apparatus has a hollow stake body with a length of 71″¾, a stake tip of 33″ in length and a hit plate with a thickness of 3″. Skilled persons will readily understand that the apparatus100may be provided in a range of length and with any number of openings150based on the expected use case. The present invention is not limited to the described variants.

The hollow stake body120of the exemplary apparatus100may be of a polygonal prism. The polygonal prism may be regular, convex or right. In a preferred embodiment, the hollow stake body120is a right octagonal prism with regular octagons for bases and rectangular faces assembled from two half shells. However, persons skilled in the art will readily recognize that the hollow stake body120may be defined otherwise, such as a cylinder, or a rectangular prism without affecting the teachings of the present invention.

In the exemplary apparatus100, the hit plate receiver130is depicted as a separate component provided on the exterior of the hollow stake body120. The hit plate receiver130could also be provided on the inside of the hollow stake body120, even though it appears less practical during assembly of the apparatus100. The hit plate receiver130, in some embodiments, is assembled from two half shells over the hollow body120and partially covers edges of the polygonal prism (e.g., bends in the hollow stake body120). The covered edges likely provide higher resistance to repeated hits then if they were uncovered (e.g., prevents or limits buckling of the hollow stake body120).

In one embodiment, the hit plate receiver130has a first end aligned with the top end of the hollow stake body120. As such, the hit plate receiver130may be placed onto the hollow stake body120as such that it is hugging the hollow stake body120. This positioning is for reinforcing the top end of the exemplary apparatus100that receives the repeated hits (e.g., as force from the repeated hits is transferred from the hit plate140onto the hit plate receiver130). Additionally, the hit plate receiver130and the top end of the hollow stake body120of the exemplary apparatus100may be inwardly tapered in order to provide a welding channel. The welding channel may be provided for increasing the strength of the bond between the hollow stake body120and the hit plate receiver130while allowing a straight top surface to be formed at the top of the hollow body120(for instance, at the time of welding or after simple machining (e.g., buffing) of the weld).

The hit plate receiver130may also present openings for providing additional weldable surfaces175with the hollow stake body120. The additional weldable surfaces175may be provided for increasing strength of the bond between the hit plate receiver130and the hollow stake body120. In a preferred embodiment, the additional weldable surfaces175are circular and present on each of the prism's faces. However, persons ordinarily skilled in the art will note that the shape of these additional weldable surfaces175may be of different shape than that of a circle, such as that of a polygon, without affecting the teachings of the present invention. In a preferred embodiment, there are 6 additional, circular weldable surfaces175, where each additional circular surface175is located on a different face of the hit plate receiver130. Supplemental surfaces175or various shapes (not shown) may optionally be provided at the edge of the hit plate receiver130or throughout the hit plate receiver130.

The bottom end of the hit plate receiver130, opposite to the top end of the hollow stake body120, may be shaped such that the length of a weld seam186therealong is longer than the perimeter of the hollow stake body120near the second end for increasing the welding surface between the hollow stake body120and the hit plate receiver130. As such, the increased welding surface increases the strength of the bond between the hit plate receiver130and the hollow stake body120. In a preferred embodiment, the weld seam186is shaped as a set of protruding teeth along the edges of the hollow stake body120, although skilled persons will recognize that other forms of the weld seam186may be used in order to achieve a weld seam where its length is greater than the perimeter of the hollow stake body120.

FIG. 1Bshows a perspective view and a top-down cross-sectional view of the exemplary apparatus100. The exemplary apparatus100may comprise a pipe176inside the hollow stake body120allowing for liquid possibly accumulated therein at a lower end and for connecting the pump hose at an upper end. In a preferred embodiment, the pipe176may be joined to the apparatus using supports177. In a preferred embodiment, the pipe176is located in the center of the hollow stake body120. However, a skilled person in the art will readily recognize that other means of joining the pipe176to the hollow stake body120, other pipe shapes and/or other pipe positioning may be used without affecting the teachings of the invention. In an alternate embodiment, the pipe176may be connected directly to the pump. The pipe176may be joined to a pump hose through a pump attachment178. In the exemplary embodiment100, the pump attachment178is curved, which may be useful for preventing the attached pump from folding onto itself and blocking the flow of liquid. Skilled persons recognize that the pipe176and the pump attachment178may have a different shape without diverging from the teachings of the present invention. The pipe176may provide an additional attachment end179for attaching to a submersible pump or a filter. Skilled persons will recognize that other apparatuses may be attached to the additional attachment end179without diverging from the teachings of the present invention. The pipe176may be made, for example, of rubber, plastic or metal. However, skilled persons will recognize that the pipe176may be made in other materials without affecting the teachings of the present invention. In a preferred embodiment, the pipe176is added into the hollow body120after positioning of the apparatus100at the site. However, skilled persons will recognize that the pipe176may be added before or during the assembly of the apparatus100. In exemplary embodiments, the submersible pump connected at the pipe176through the additional attachment end179may have a diameter that fits within the hollow body120.

As shown inFIG. 1AandFIG. 1D, in a preferred embodiment, the hit plate140comprises a first pair of handles180which are attached to the hit plate140. In the depicted example, the handles180are placed symmetrically at opposite ends of one another. The first pair of handles180may be welded, for example, to the hit plate140. However, other means for attaching these handles180may be used. The handles180may be for positioning the hit plate140onto and removing the hit plate140from the exemplary apparatus100. For example, the removal of the hit plate140may be performed after reaching a desired depth with the apparatus100and before insertion of the pump hose into the hollow stake body120which will remove liquid accumulated within (not shown). Alternate embodiments of the hit plate140may provide one, two, or more handles180. The position of the handles180may also vary along the hit plate140without departing from the teachings of the present invention. Additionally, a person ordinarily skilled in the art will readily recognize that the handles180may be replaced by other means of offering a latching point for removing the hit plate140, such as a pair of protruding bars or protruding bolts, without affecting the teachings of the invention (not shown).

A preferred embodiment of the present invention also comprises a second pair of handles170. The handles170are attached to the hollow stake body120. The second pair of handles170may be welded, for example, to the hollow stake body120(e.g., between the body120and the receiver130). However, other means for attaching these handles170may be used. An alternate embodiment may present an apparatus where one, or more than two handles170are attached to the hollow stake body120. In the depicted example, the handles170are placed symmetrically at opposite ends of one another for improving and optimizing the removal of the exemplary apparatus100from the ground. The position of the handles170may also vary along the hollow body120without departing from the teachings of the present invention. The pair of handles170may be for extracting the apparatus100from the ground, using, for example, hooks which may be inserted into the handles170, where an upward force, exerted by a crane, for example, will hoist the exemplary apparatus100from the ground for removal from the excavation site. A person ordinarily skilled in the art will readily recognize that the first pair of handles170may be replaced by other means of offering a latching point for removing the exemplary apparatus100from the ground, such as a pair of protruding bars or protruding bolts, without affecting the teachings of the given invention (not shown).

As shown inFIG. 1D, in a preferred embodiment of the exemplary apparatus100, the hit plate140may comprise a set of reinforcements185. The exploded view ofFIG. 1Dprovides a perspective view of the upper part of the exemplary apparatus100. In a preferred embodiment, the pair of reinforcements185are placed symmetrically at opposite ends from one another, on a surface of the hit plate140, in such a way that the pair of reinforcements185will be enclosed within the hit plate receiver130, and subsequently the exemplary apparatus100, when the hit plate140is to be positioned onto the hit plate receiver130. The pair of reinforcements185may further facilitate the placement of the hit plate140onto the hit plate receiver130, functioning as a guide during the positioning of the hit plate140. The reinforcements185may also allow the hit plate140to better keep its shape over time as the hit plate140recurrently receives repeated hits. Without the reinforcements185, the hit plate140may be more prone to deforming under the applied force of the repeated hits, causing the removal of the hit plate140to be difficult for subsequent use. The pair of reinforcements185may further be provided for reinforcing the overall structure of the hit plate140. The number of reinforcements185found on the hit plate140, as well as the positioning of the reinforcements185on the hit plate140, may vary without affecting the teachings of the present invention.

The plurality of lateral openings150of the exemplary apparatus100may be positioned on one or more surfaces125defined by the polygonal prism. The plurality of lateral openings150may be interspersed for limiting stress formation along the hollow stake body120.

A preferred embodiment comprises three lateral openings150on each face of the hollow stake body120, totaling 24 lateral openings150, where the lateral openings150found on each face are offset in regards to the lateral openings150found on an adjacent face. Another embodiment of the exemplary apparatus100may provide that the plurality of lateral openings is interspersed on a circular surface of a hollow stake body.

The exemplary apparatus100may also provide the plurality of lateral openings150towards the stake tip110for improving the capture of liquid deeper into the ground. However, skilled persons will recognize that the number lateral openings150, the organization into rows, the positioning and the size of the lateral openings150may vary without affecting the teachings of the present invention.

Reference is now concurrently made toFIGS. 1C, 1C-1, 1C-2 and 1C-3. As shown thereon, the plurality of lateral openings150of the exemplary apparatus100may also comprise at least one type of mesh182A and/or mesh182B, concurrently defined as mesh182. The mesh182allows liquid to permeate into the hollow stake body120while blocking undesired debris. The mesh182may be selected considering the liquid to be controlled (e.g., when thicker petroleum products is expected, to avoid or limit clogging). A person skilled in the art will readily recognize that the mesh182may be replaced by another material which allows liquid to permeate through a surface (e.g. a filter, a very fine sieve) without affecting the teachings of the present invention. A mesh is defined as a woven, knit, or knotted material of open texture with evenly spaced holes or as like a web-like pattern or construction. In the exemplary apparatus100, the mesh182may be a 12×64 stainless steel mesh, a 80μ mesh or a 120μ mesh. Stainless steel is chosen for the composition of the mesh182in order to reduce corrosion of the mesh182. A skilled person in the art will readily recognize that the mesh182may be of a different type along a single apparatus100based on an intended use (e.g., finer mesh at the bottom opening150of the apparatus100compared to the higher openings150). Likewise, the mesh182itself may also present a different permeability along its length and/or width.

The mesh182of the exemplary apparatus100may be sandwiched between an outward punctured cover181and an inward punctured cover183.FIG. 1C-1provides a sectional view of along the cut line A-A fromFIG. 1Csuch exemplary arrangement. The outward punctured cover181may comprise elongated apertures184along a longitudinal axis of the hollow stake body120. The elongated apertures184may prevent foreign bodies found in the ground (e.g. rocks, roots, twigs) from puncturing or damaging the mesh182. However, a skilled person will recognize that other means for protecting the mesh182, such as, for example, a wire grid, may be used in addition or in replacement of the elongated apertures184. The mesh182may be welded to the outward punctured covered181and the inward punctured cover183. However, other means for attaching the mesh182to the outward punctured cover181and the inward punctured cover183may be used, such as bolts, which facilitates the replacement of the mesh182. Replacement of the mesh182may be for use of the exemplary apparatus100in different ground compositions or to facilitate the replacement of a damaged mesh. The outward punctured cover181may be thicker (e.g., when compared to the inward punctured cover183or the mesh182) for preventing deformation of the mesh assembly.

FIG. 2shows an exemplary apparatus200where the stake tip210is of a filled, pyramidal shape. Persons skilled in the art will note that the shape of the stake tip210may vary as long as the stake tip210fills its function of facilitating piercing of the ground when force is applied in a downward direction on the exemplary apparatus200without affecting the teachings of the present invention. Alternative embodiments may provide a stake tip, for instance, in the shape of a marker or a fence pole.

FIG. 3shows a perspective view of some disassembled components of an exemplary apparatus for allowing control of liquid level on a site. A hollow stake body may be made using two hollow stake body sheets320. The hollow stake body sheet320may be folded along bends326, delimiting faces325of a polygonal prism, in the longitudinal direction of the hollow stake body, in order to form half of the polygonal prism. A preferred embodiment comprises four bends326on the hollow stake body sheet326. Two hollow stake body sheets320may be placed opposite to one another to form the hollow stake body. The two hollow stake body sheets320may be, for example, welded to one another for solidifying the hollow stake body. A person skilled in the art will recognize that a hollow stake body may be composed of one hollow stake body sheet, where one of the longitudinal edges meets the other longitudinal edge once the hollow stake body sheet is folded, or more than two sheets (e.g., welded together) without diverging from the teachings of the present invention (not shown).

A hit plate receiver may be made using two hit plate receiver sheets310. The hit plate receiver sheet310may be folded along a bend316, delimiting faces315of a polygonal prism, in the longitudinal direction of the hit plate receiver, in order to form half of the polygonal prism. A preferred embodiment comprises four bends316on the hit plate receiver sheet310. Two hit plate receiver sheets310may be placed opposite to one another to form the hit plate receiver. The hit plate receiver sheets310may be welded to one another for solidifying the hit plate receiver. A person skilled in the art will recognize that a hit plate receiver may be composed of one single hit plate receiver sheet, where one of the longitudinal edges meets the other longitudinal edge once the hit plate receiver sheet is folded along its bends, or more than two sheets (e.g., welded together) without diverging from the teachings of the present invention (not shown). In another embodiment, the hit plate receiver130is shaped as a cylinder having an internal diameter that matches the longest external diagonal of the base of the hollow body120. The hit plate receiver130can then be positioned over the hollow body120(e.g., press fit, welded, etc.) to provide its intended function.

FIG. 4shows a perspective view of some of the disassembled components of an exemplary embodiment of a stake tip of an exemplary apparatus for allowing control of liquid level on a site. A first wedge430may be inserted into a spacing425of a second wedge420. In turn, the second wedge420falls into a spacing435of the second wedge430. The spacing of the first wedge425and the spacing of the second wedge435provide an assembly method which increases the overall stability of the stake tip. The assembled first430and second420wedges may be attached (e.g., welded) to one another and onto a polygonal shaped plaque410. The plaque410may be of another shape than that of a polygon, such as an oval or a circle, as long as the hollow stake body and the hit plate receiver have a shape compatible with the plaque410. In a preferred embodiment, the plaque410is 1″ thick. Skilled persons will notice that the thickness of the plaque410may vary without departing from the teachings of the present invention.

FIG. 5shows a top-down view of a disassembled hollow stake body and hit plate receiver of an exemplary apparatus for allowing control of liquid level on a site. The hollow stake body may be composed of two parts, a first part510and a second part520, where both parts may be assembled to form a polygonal prism. A first axis of symmetry is formed passing through the points marking where the first part510and the second part520meet. The hit plate receiver may also be composed of two parts, a first part530and a second part540, where both parts may be assembled to form the hit plate receiver. A second axis of symmetry is formed passing through the points marking where the first part530and the second part540of the hit plate receiver meet. The first axis of symmetry550and the second axis of symmetry560are placed relative to one another in such a way to minimize stress points of the apparatus, where a welding seam is a stress point and so the welding points are not juxtaposed. The first part510and second part520may be welded together once assembled, to form the hollow stake body. The first part530and second part540may be welded together once assembled, to form the hit plate receiver. As mentioned with reference to the embodiment ofFIG. 1, a welding channel570may be provided between the hollow stake body and the hit plate receiver when assembled. During assembly, a welding seam at least partly fills the welding channel570. In some embodiments, the welding seam completely fills the welding channel570and it may be necessary to machine (e.g., buff) excess material therefrom to form a straight top surface.FIG. 5provides exemplary axis of symmetry that may provide different angular differences.

FIG. 6shows a flow chart of an exemplary method600for controlling liquid level on an excavation site. The method600comprises positioning, at one location on the site, a first apparatus comprising a hollow stake body (A;605). The hollow stake body comprises a plurality of lateral openings permeable to liquid (e.g., allowing liquid to enter and/or air to exit), a stake tip at one end of the hollow stake body and a hit plate receiver at an opposite end of the hollow stake body. The method600also comprises positioning a first hit plate on the hit plate receiver of the first apparatus (B;610) and then repeatedly hitting the first hit plate until at least one of the plurality of lateral openings is below ground at a liquid control depth (C;620). This force is for driving the apparatus into the ground. Additionally, the method600comprises removing the first hit plate form the first apparatus (D;630). The method600also comprises installing a pump for pumping liquid accumulated in the hollow stake body of the first apparatus (E;640), thereby removing the accumulated liquid.

The method600may also further comprise excavating the site (F;650), removing the pump from the first apparatus (G;660) and repeating at least B to E, as shown onFIG. 6, for controlling the liquid control depth before resuming F (H;670). These actions allow for removal of liquid at an excavation site at continuously lower depths in the ground as the excavation progresses and more liquid, found in the ground, hinders the progression of the excavation.

The method600may comprise repeating at least A to E, as shown onFIG. 6, with at least one additional apparatus and at least one additional location along a perimeter within the excavation site (I;680) using multiple apparatuses for covering a larger surface area in the case of a larger excavation site. In a preferred embodiment, four apparatuses, therefore three additional apparatuses, are positioned in a parallelogram formation in order to cover a maximum area of an excavation site. Each apparatus covers optimally a given area of the excavation site in order to drain liquid. The emplacement of each apparatus in regards to one another should be such as to reduce overlap of the liquid drainage surface area over the excavated area.

Another aspect of the invention is a mesh construction for installing onto an apparatus for controlling liquid level on a site which comprises a first punctured cover, a second punctured cover and a mesh assembly. The mesh assembly comprises at least one filtration mesh, which may be sandwiched between a first punctured cover and a second punctured cover for allowing liquid and/or air therethrough when the mesh construction installed on an apparatus underground at a site. The mesh assembly may comprise a mesh type which is a 12×64 stainless steel mesh, an 80μ mesh or a 120μ mesh. Stainless steel is chosen for the composition of the mesh assembly in order to reduce corrosion of the mesh assembly. A person skilled in the art will readily recognize that the mesh assembly may be replaced by another type of mesh without affecting the teachings of the present invention. The filtration mesh may be welded to the first punctured cover and to the second punctured cover. However, other means for attaching the mesh to the first punctured cover and the second punctured cover may be used, such as bolts, which facilitates the replacement of the mesh. Replacement of the mesh may be for use of the exemplary apparatus in different ground compositions or to facilitate the replacement of a damaged mesh.

The mesh construction may also be placed on the walls of a trench cage in an excavation site for allowing liquid from the ground around the trench cage, which further allow for stabilizing the ground neighboring the trench cage. One or more apparatuses100for controlling liquid level on a site may be placed inside the trench cage for receiving liquid draining from the mesh constructions. Skilled person will recognize that the mesh construction may be used in different context on different types of devices where liquid may be controlled from ground on a side of such devices (e.g., during ground shoring).

FIG. 7shows a perspective view of an embodiment of a mesh construction700for installing onto an apparatus for controlling liquid level on a site where a bolt attachment720is shown. In this example, the mesh construction700is attached to a hollow stake body710using a bolt attachment720. The bolt attachment720is then further inserted into an attachment point750of an attachment support740. The attachment support740may be found on the hollow stake body120around the ridges of a spacing760for receiving the mesh construction700. The attachment support740may be protruding inwardly on the ridges of the spacing760for not hindering the insertion of the mesh construction700into the spacing760. In a preferred embodiment, the bolt attachment720may be a tapered flat head screw in order for the bolt not to protrude (or to arrive flush) with the mesh construction700when fully inserted into a mesh construction tapered hole730. Skilled persons will notice that the bolt attachment720may be of other types than a tapered flat head screw without diverging from the teachings of the present invention. In a preferred embodiment, two bolt attachments720are used to attach the mesh construction700to the hollow stake body710, passing through two tapered holes730for receiving one of the two bolt attachments720respectively, and two attachment supports740are used for receiving the bolt attachments720, where the tapered holes730and the attachments supports740are placed longitudinally at opposite ends of one another.

Some embodiments may provide one or more than two bolt attachments720, tapered holes730and attachment supports740. Additionally, in some embodiments, the number of attachment supports740may be greater than the number of bolt attachments720, where the additional attachment supports740are for solidifying and offering additional support to the mesh construction700when inserted into the spacing on the hollow stake body710. Additionally, skilled persons will recognize that the number of bolt attachments720, attachment supports740and the location of the bolt attachments720and attachment supports740may vary depending on size, weight and required tension of the mesh construction700when inserted into the spacing760of the hollow stake body710. As skilled person will readily appreciate the size of the different components720-750may differ without affecting the described functionality. Other types of attachment mechanisms (e.g., nuts and bolts, snap on, press fit, etc.) may also be used to maintain the mesh construction700into the hollow stake body710while sustaining the expected pressure from its intended use.

In some embodiments, the bolt attachments, as the bolt attachments are inserted into the tapered holes and subsequently into the attachment point of the attachment support, may also attach the mesh assembly to the first punctured cover and the second punctured cover without the need for welding, where the number of bolt attachments may vary for increasing the solidity of the attachment between the mesh assembly, the first punctured cover and the second punctured cover.

The mesh construction700may also comprise a sealing frame (not shown), covering the complete perimeter of the spacing760, positioned within the hollow stake body710to support the mesh construction700once the mesh construction700is inserted into the spacing760. The sealing frame may be used for preventing infiltration of liquid into the apparatus through the gap between the mesh construction700and the hollow stake body710once the mesh construction700is bolted to the hollow stake body710, enhancing the seal between the mesh construction700and the hollow stake body710. The shape, thickness and width of the sealing frame may vary in order to accommodate different forms of mesh constructions. The shape of the mesh construction may be different from the shape of the spacing in the hollow stake body, where the sealing frame compensates for these differences in shape and seals the gap and preventing liquid infiltration. The sealing frame may be provided as a plate soldered from within the hollow stake body710. The shape of the plate may be different that the spacing760. The shape of the plate may also be provided to avoid interference with the filtration mesh (e.g., not positioned over opened portions of the mesh construction). In a preferred embodiment, the sealing frame is made of steel. However, skilled persons will recognize that the sealing frame may be made of other materials without departing from the teachings of the present invention.

In a preferred embodiment, the sealing frame further provides a rubber seal. A rubber may also (alternatively or in addition) be provided with the mesh construction. For instance, the rubber seal may be provided between the first punctured cover and the second punctured, around the filtration mesh. When the mesh construction is assembled with bolts, the rubber seal may be further shaped so as to protrude under the compression force exerted during assembly of the mesh construction and/or during installation of the mesh construction in the spacing760using the bolt attachment720.

The mesh assembly may further comprise a protective mesh over the filtration mesh and the first punctured cover, the first punctured cover being outwardly positioned when the apparatus is underground at the site. The protective mesh is for preventing foreign bodies from piercing or damaging the mesh and deflecting these foreign bodies when the apparatus is in the ground. A preferred embodiment provides a filtration mesh which is a grille. However, skilled persons will notice that the filtration mesh may be instead a framework of metal bars, a hard cover punctured with large gaps or any other means of protecting the mesh while allowing liquid and/or air to flow through, into the mesh and into a hollow stake body, without departing from the teachings of the present invention. In a preferred embodiment, the first punctured cover is thicker than the second punctured cover.

The mesh construction may also provide the first punctured cover with elongated apertures along a longitudinal axis of the apparatus for protecting the mesh assembly when the apparatus is being put into the ground. The elongated apertures offer an initial barrier for foreign bodies (e.g. wood, rocks and sticks) while allowing liquid to flow through.

The description of the present invention has been presented for purposes of illustration but is not intended to be exhaustive or limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art. Elements in the drawings are not necessarily drawn to scale. The embodiments were chosen to explain the principles of the invention and its practical applications and to enable others of ordinary skill in the art to understand the invention in order to implement various embodiments with various modifications as might be suited to other contemplated uses.