Patent Description:
Steel sheet pile systems are commonly used in marine environments such as ports, docks and channels to construct walls, which extend above and below the water level, and retain land or soil on one side and water on the other. The near-vertical face provided by the sheet pile wall provides a convenient geometry for vessels to approach the wall, in comparison to sloped rock walls or natural shoreline. Sheet piles are long structural steel sections, typically driven into the underlying ground and interlocked along a vertical joint to create a continuous wall. A variant of sheet pile walls is the combined wall consisting of sheet piles and tubular steel piles, or other variants, interlocked together.

Sheet pile walls sometimes include tie-backs, waling beams or other elements as part of their design. Tie backs are commonly steel rods that anchor the wall within the soil on the land side. They commonly have a threaded end that protrudes through the sheet pile wall and is retained with a plate and nut on the water side of the sheet pile wall. The inclusion of waling beams and other structural elements located on land-side of the wall may also include bolts, plates and other fixings on the water side of the sheet pile wall. The water-side face of a sheet pile wall is commonly referred to as the outside face or outer surface.

Steel sheet piling and fixings will corrode in a marine environment if not protected by a corrosion protection system. This corrosion will result in loss of thickness of the steel and may lead to loss of integrity and failure of the sheet pile wall. Existing corrosion protection systems commonly used include paint coatings and concrete encasement.

Regular, hollow cylindrical piles that are discreet and not joined into a wall are commonly protected by the layered application of an anticorrosive gel, a cloth or foam material impregnated with an anticorrosive gel and a flexible protective covering that wraps around the material and is attached back onto itself, to ensure that the anticorrosive gel or material is pressed against the steel surface of the pile.

Because the pile is circular in cross-section and the protective covering is applied around the full circumference, the protective covering typically holds the anticorrosive material against the steel surface by the application of pressure induced by hoop tension in the protective covering, or by hoop tension in a series of straps that hold the protective covering in place.

These systems described above are sometimes used on discrete piles that are not circular in cross-section and may have concave features, such as H-piles. In these cases a semirigid material may be used between the protective covering and the anticorrosive gel or impregnated cloth material to fill the gap therebetween.

The above system cannot be used on sheet pile walls because it is not possible to extend the protective covering around the circumference of the wall elements, for the opposite ends to be brought together to induce hoop tension in the protective covering.

In addition, rigid covers for sheet pile walls have been proposed. These covers are designed to have a shape following the exact profile of the wall. In the event of mismatch in shape or minor variations in dimensions due to manufacturing, voids may be created where the wall is exposed to the environment. Such covers also create voids around wall fittings, and portions of the wall can become exposed depending on weather and sea temperature due to different rates of thermal expansion of the wall and cover. Another drawback of such rigid covers is that they must be constructed of a high stiffness, corrosion resistant (i.e. expensive) material.

Thus there exists a desire or need for an assembly or method for protecting a wall, particularly a sheet pile wall, from environmental impacts, such as those imposed by a marine environment.

The reference in this specification to any prior publication (or information derived from it), or to any matter which is known, is not, and should not be taken as an acknowledgment or admission or any form of suggestion that the prior publication (or information derived from it) or known matter forms part of the common general knowledge in the field of endeavour to which this specification relates. <CIT> discloses (Abstract): "PROBLEM TO BE SOLVED: To make it possible to improve the adhesion of a petrolatum anticorrosive material to a steel pipe body or a bottom side wall surface of a recess bottom part, for preventing the exterior wall surface of a steel pipe sheet pile wall from being corroded. SOLUTION: An exterior wall surface 9a of a steel pipe sheet pile wall <NUM> is covered by a plurality of anticorrosion covers <NUM> each composed of a petrolatum anticorrosive layer <NUM> brought into contact with the exterior wall surface 9a of the steel pipe sheet pile wall <NUM> and an anticorrosive metal plate <NUM> outside the petrolatum anticorrosive layer with a cushioning material <NUM> interposed therebetween. The plurality of anticorrosion covers <NUM> are fixed, with side end side parts thereof overlapped with each other in a concave bottom section <NUM> formed between adjacent steel pipe bodies <NUM>. Tensile force in a circumferential direction is introduced into the cross-section arc-shaped anticorrosive metal plates <NUM> of the anticorrosion covers <NUM> covering an outer peripheral surface 5a of the steel pipe bodies <NUM> by a tension introduction device <NUM> provided in the concave bottom section <NUM>.

In one broad form an aspect of the present invention seeks to provide a protection assembly for protecting a wall, comprising: a coating system for coating a portion of the wall; a flexible covering for covering the coating system, and having fixing portions at end regions of the flexible covering; and a wall anchor system, wherein, in use, the coating system is located between the flexible covering and wall anchor system, and the flexible covering is anchored, at the fixing portions, in a tensioned condition to the wall by the wall anchor system, so the flexible covering produces a force to press the coating system against the wall.

In one embodiment the fixing portions are anchored to the wall at spaced apart locations.

In one embodiment the flexible covering comprises a flexible sheet, and the end regions are opposed ends of the flexible sheet.

In one embodiment the flexible covering comprises one or more straps, and each of the fixing portions comprises a respective one of two opposed ends of each strap of the one or more straps.

In one embodiment the flexible covering further comprises a flexible sheet held, in use, against the coating system by the one or more straps, and wherein the one or more straps are tensioned to produce at least a part of the force to press the coating system towards the wall.

In one embodiment each strap of the one or more straps comprises: two sections, each section comprising one of the respective two opposed ends; and a buckle connecting the sections, the strap being operable to draw at least one of the sections through the buckle to apply tension to the respective strap.

In one embodiment the wall anchor system is connected to the end regions of the flexible covering and operable to apply tension to the flexible covering.

In one embodiment the fixing portions are tensioned in divergent directions.

In one embodiment the wall anchor system comprises: two elongate members each fixed, in use, to the wall at spaced apart locations; and a plurality of fasteners associated with each elongate member and being for fastening one of the fixing portions to the respective elongate member at spaced locations along the respective elongate member.

In one embodiment the protection assembly is for protecting the wall from a marine environment, the wall being elongate in a horizontal direction and the fixing portions being anchored, in use, at spaced apart locations in the horizontal direction.

In one embodiment the wall is non-planar, and the coating system is shaped so that the flexible covering applies force to press the coating system against the wall along a full length of the flexible covering.

In another broad form an aspect of the present invention seeks to provide a method for protecting a wall, comprising: applying a coating system to a portion of the wall; covering the coating system with a flexible covering having fixing portions at end regions of the flexible covering; and anchoring the flexible covering, at its fixing portions, to the wall in a tensioned condition using a wall anchor system so the flexible covering produces a force to press the coating system against the wall.

In one embodiment anchoring the flexible covering at its fixing portions comprises anchoring the fixing portions to the wall at spaced apart locations.

In one embodiment anchoring the flexible covering at its fixing portions comprises tensioning the flexible covering in divergent directions.

In one embodiment tensioning the flexible covering comprises operating the wall anchor system to apply tension to the flexible covering.

In one embodiment the flexible covering comprises one or more straps, each strap comprising two opposed ends, each fixing portion comprising one of the opposed ends, and anchoring the flexible covering comprises: attaching the one or more straps to the wall anchor system; and tightening the one or more straps.

In one embodiment the flexible covering further comprises a flexible sheet and covering the coating system comprises covering the coating system first with the flexible sheet and then holding the flexible sheet to the coating system using the one or more straps.

In one embodiment the method is for protecting the wall from a marine environment, the wall being elongate in a horizontal direction, wherein the wall anchor system comprises: two elongate members; and a plurality of fasteners associated with each elongate member, for fastening one of the fixing portions to the respective elongate member at spaced locations along the respective elongate member, wherein anchoring the flexible covering comprises: fixing the two elongate members to the wall at spaced apart locations; and fastening one of the fixing portions to the respective elongate member using a respective one of the pluralities of fasteners.

In one embodiment the method further comprises shaping the coating system so that the flexible covering applies force to press the coating system against the wall along a full length of the flexible covering.

In another broad form an aspect of the present invention seeks to provide a method of protecting one or more wall fittings, comprising: performing the above described method; shaping the flexible covering to fit around one or more wall fittings; providing an encasement shaped to be received over the one or more wall fittings and over an outer surface of a protection assembly component, the protection assembly component being one or more of the flexible cover, coating system and wall anchor system; and fitting the encasement to the outer surface of the protection assembly component.

It will be appreciated that the broad forms of the invention and their respective features can be used in conjunction, interchangeably and/or independently, and reference to separate broad forms is not intended to be limiting.

Various examples and embodiments of the present invention will now be described by way of non-limiting example and with reference to the accompanying drawings in which: -.

The protection assembly and related methods described in various embodiments herein is intended to protect a wall, or portion of a wall, from an environment. The protection assembly and method may be particularly useful in marine environments. In some embodiments, a method is provided for preventing corrosion of a steel sheet pile wall by application and retention of an anticorrosive gel, being part of a coating system, against the outside face of a sheet pile wall. The anticorrosive gel is typically petroleum or petrolatum based and prevents corrosion by preventing oxygen and water from reaching the steel surface of the sheet pile wall. The protection assembly may be directed toward ensuring that the anticorrosive gel is kept in intimate contact with the outside face of the steel sheet pile wall and is not removed through the action of waves, water, abrasion or other actions. The embodiments described herein include several elements and features intended to prevent disturbance of the anticorrosive gel layer.

It will be understood from the present disclosure that protecting a wall may refer to protecting part of the wall, rather than the wall in its entirety. Therefore, the phrases "protecting a portion of a wall" and "protecting a wall" will be understood to have similar meaning, namely referring to the relevant part of the wall (i.e. the part likely to be adversely affected if not protected), unless context dictates otherwise. Similarly, the term "a portion of a wall" and similar may refer to all or part of a wall, and will generally refer to protection on the outer surface of that wall unless context dictates otherwise. The outer surface is the surface facing the environment from which the protection assembly gives protection. It will be appreciated that some portions of the wall are not exposed to the environment, or are exposed inconsistently so that there is a lesser need to use a protection assembly in accordance with present teachings, for protecting those portions. For example, in a marine environment, a portion of a wall that is regularly below water level and/or is periodically submerged by normal tidal or wave movement, will require more protection than portions of the same wall that are sufficiently elevated to avoid the usual impact of waves.

An example of a protection assembly for protecting a wall, will now be described with reference to <FIG>. The protection assembly <NUM>, interchangeably referred to as assembly <NUM>, is applied to the outside face or surface of a sheet pile wall <NUM>. Sheet pile wall <NUM> is composed of individual piles joined at joints <NUM>. The sheet pile wall <NUM> retains soil <NUM> on one side and is exposed to the water and atmosphere <NUM> on the other side referred to as the outside of the sheet pile wall <NUM>.

The protection assembly <NUM> broadly comprises a coating system <NUM>, flexible covering <NUM> and wall anchor system <NUM>.

The coating system <NUM> is for coating a portion of the wall <NUM>. As mentioned above, the portion of the wall <NUM> may be the entirety of the wall, or only a part of the wall such as that part which is impacted by an environment from which it is desirable to protect the wall. The coating system <NUM> shown in <FIG> includes a number of different layers. The layers are applied to the outside face of the sheet pile wall. The layers include a barrier material layer, presently comprising anticorrosive gel layer <NUM>, a tape layer <NUM> that may contain further barrier material, and a rigid or stiff shaping layer, presently comprising a rigid foam layer <NUM>.

The anticorrosive gel layer <NUM> is applied to the outside face of the wall <NUM>. The anticorrosive gel of layer <NUM> is typically petrolatum based. However, the layer <NUM> may instead be formed using another suitable barrier material - i.e. a material the presence of which, on the outer surface of the wall <NUM>, prevents impact from the environment <NUM> on that outer surface - which may be a flowable material at least at the time of application to the wall <NUM>. Such flowable materials may have no fixed shape, such that they can be taken from a volume (e.g. a can or vat) and spread over the outer surface of the wall. In the present context, other gels such as hybrid petrolatum gels, and some waxes may be suitable for use in forming layer <NUM>.

The tape layer <NUM> comprises a tape of cloth material or foam. The tape is typically a non-woven cloth. The layer <NUM> may further comprise barrier material, e.g. petrolatum material, impregnated into the cloth prior to application to the wall <NUM>. The material impregnating the cloth may be the same material as that which forms layer <NUM>, or a different material as needs be. The cloth and impregnating material together produce a product with a thickness of typically between <NUM> and <NUM>, that may be supplied on a roll.

The tape layer <NUM> may be replaced by any other material, for example a broad sheet of material of sufficient flexibility to be shaped to conform to the shape of the outer surface of the wall <NUM>.

Where the layer <NUM> is impregnated with barrier material, there may be no need to provide layer <NUM>. Thus, the coating system <NUM> may, in some embodiments, include only one of layers <NUM> and <NUM>.

In the examples shown in the figures the wall <NUM> is non-planar. The outer surface of wall <NUM> comprises various angles and, for composite or combined walls, changes in cross-section. The angles and changes in cross-section assist with distributing force into the soil <NUM>, provide structural strength and stability against force from water, particularly waves, bearing against the wall <NUM> and reaction forces from the soil <NUM>. However, if the flexible cover <NUM> is tensioned over angled sections of the wall <NUM> there may, for some sheet pile wall designs, be voids created behind the flexible cover. Water may flow into those voids and dislodge layer <NUM> and/or wash away layer <NUM>. The the effectiveness or longevity of the protection assembly <NUM> may be reduced.

The protection assembly <NUM> should therefore accommodate angles and changes in cross-section in a horizontally elongate wall, while maintaining the pressure against layer <NUM> and/or <NUM> to avoid the creations of voids. To achieve this, the coating system <NUM>, particularly layer <NUM>, is shaped to remove voids between the flexible covering <NUM> and wall <NUM>, to enable the flexible covering <NUM> to be tensioned over the coating system <NUM>, around changes in the shape of the wall <NUM>, while maintaining pressure on layer <NUM> and/or <NUM>. Layer <NUM> ensures force or pressure from the flexible covering <NUM> is applied over more of, or the entirety of, the outer face of the portion of the wall <NUM> covered by the flexible cover <NUM>.

Layer <NUM> assists in ensure the force or pressure applied by the flexible covering <NUM> is applied across the outer face of the wall <NUM>. To that end, layer <NUM> is shaped so that the side facing the sheet pile wall <NUM> follows the profile of the sheet pile wall <NUM>. The outside of the layer <NUM> is shaped to provide a convex curve between the edge of the wall anchor system <NUM> (particularly spine <NUM>) and the outside corner <NUM>, seen on <FIG>, of the sheet pile wall <NUM>. The curve may be continuously convex, or may generally convex (e.g. may include one or more flat portions). However, in the embodiment shown, concave sections are avoided.

The layer <NUM> is formed from foam which may be rigid. The layer <NUM> may be constructed of expanded polystyrene. The layer <NUM> may be segmented into two or more section shapes as shown in <FIG>. This segmentation allows easier installation and enables better matching of the profile of the sheet pile wall in the vicinity of some features - e.g. joints between sheets of the wall <NUM> - and can help account for slight dimensional variations between sheets of the wall <NUM> due to manufacturing and installation tolerances. The layer <NUM> may also be supplied in convenient lengths to simplify the installation. Those lengths may match the width of the flexible covering <NUM> (i.e. its vertical height when the flexible covering <NUM> extends laterally/horizontally across the wall <NUM> between fixing portions as best seen in <FIG>), or the width of the flexible sheet <NUM> may be a whole number multiple of the length of the segments of layer <NUM>.

While in the embodiment in <FIG> layer <NUM> comprises a rigid foam <NUM>, other types of rigid or stiff filler may be used. The rigid foam may be expanded polystyrene. In some embodiments, the layer <NUM> may have barrier material resident in the voids in the layer <NUM>, such as voids in the rigid foam. This may provide sufficient barrier material to protect the wall <NUM> without the need for one or both of the layer <NUM> and layer <NUM>. The coating system <NUM> may therefore include any one or more of layers <NUM>, <NUM> and <NUM>, in any combination, as appropriate for a particular application.

The flexible covering <NUM> covers the coating system <NUM>. The flexible covering <NUM>, interchangeably referred to as a protective covering, consists of a flexible sheet <NUM> and fixing portions, presently each a rigid flange <NUM>, at ends or end regions generally designated <NUM>. The sheet <NUM> and flange <NUM> may both be constructed of high density polyethylene and are preferably bonded together by a plastic weld <NUM>. The fixing portions <NUM> are portions of the flexible covering <NUM> by which the flexible covering connects to the wall <NUM> via wall anchor system <NUM>.

The sheet <NUM> may be of around <NUM> thickness. The flexible sheet <NUM> may be made of high density polyethylene, or a fabric reinforced polymer, and the flange <NUM> may be constructed of a strong rigid material such as fiberglass. In this embodiment the flange <NUM> may be circular in cross-section and will typically be retained by wrapping the sheet <NUM> around the flange and joining it back upon itself by sewing. Other embodiments of the protective covering <NUM> are possible.

The flange <NUM>, or other fixing portion as may be used in accordance with present teachings, attaches the flexible covering <NUM> to the wall <NUM> via wall anchor system <NUM>. When anchored to the wall <NUM>, the flexible covering <NUM> is in a tensioned condition - i.e. is under tension. The covering <NUM> generally forms a curve as shown in <FIG>, and thus has a radius - the radius may vary along the flexible covering <NUM>. Therefore, the tension in the covering <NUM> - which may be referred to as hoop tension - produces a force (which may be a radial force) in the direction of the wall <NUM>. That force presses the coating system <NUM>, which is between or interposes the flexible covering <NUM> and wall <NUM>, against the wall <NUM>.

The wall anchor system <NUM> is attached to the wall <NUM> at spaced apart locations <NUM><NUM>. The fixing portions <NUM> are anchored to the wall <NUM>, by wall anchor system <NUM>, at spaced apart locations <NUM>, <NUM>. Therefore, the fixing portions <NUM>, and thus the flexible covering <NUM>, are attached to the wall <NUM> at spaced apart locations <NUM>, <NUM>.

The flexible or protective covering <NUM> is preferably sized so that the distance between the faces of the two flanges <NUM> - i.e. the side <NUM> shown facing the wall <NUM> in <FIG> when the flexible covering <NUM> is anchored to the wall <NUM> - is slightly smaller than the distance between the respective mating faces <NUM> on the wall anchor system <NUM> (on respective adjacent spines <NUM> of the wall anchor system <NUM> at locations <NUM>, <NUM> as discussed below) when measured along an arc following the outside of layer <NUM> and the flat face <NUM> of the sheet pile wall <NUM> between portions of the layer <NUM> in the embodiment in <FIG>.

The flexible covering <NUM> is attached to the wall anchor system <NUM> by fasteners <NUM>. When the fasteners <NUM> are tightened, the flange <NUM> of the flexible covering is brought into contact with the mating face <NUM> of the wall anchor system <NUM>, or spine <NUM> thereof - while the phrase "the flange <NUM> of the flexible covering <NUM> is brought into contact with the mating face <NUM>" implies direct contact, that phrase, and similar phrases used herein, include within their scope indirect contact as required by context. For example, the flange <NUM> may contact the spine <NUM> by application of pressure through the sheet <NUM>.

Due to its shorter length, the protective covering <NUM> is caused to deform - e.g. stretch - over its length. This deformation may be a combination of plastic and elastic deformation. The sheet <NUM> of the protective covering <NUM> will be in tension along its length and, due to its convex path, this tension will exist as a hoop tension and, therefore, exert a pressure against the rigid foam <NUM>. This pressure will cause the rigid foam to be pressed toward the surface of the sheet pile wall <NUM>. This action causes the tape <NUM> and anticorrosive gel <NUM> to be pushed against the surface of the sheet pile wall <NUM>. This pressure displaces water and fills voids - e.g. by pressing anticorrosive gel layer <NUM> thereinto. The tape <NUM> and gel <NUM> are thus reliably retained against the surface of the sheet pile wall <NUM> and are not removed by wave, weather or other expected actions. Corrosion to the steel sheet pile wall <NUM> is thus prevented.

As the wall <NUM> is elongate, rather than having a generally circular cross-section, the flexible covering <NUM> cannot wrap around and attach back onto itself in order to be tensioned. To ensure proper engagement between the flexible covering <NUM> and wall <NUM>, the flexible covering <NUM> is attached to the wall <NUM> via wall anchor system <NUM>. In the present embodiment, the wall anchor system <NUM> includes fasteners <NUM> by which to attach the wall anchor system <NUM> to the flexible covering <NUM>. The wall anchor system <NUM> is connected to the end regions <NUM> of the flexible covering <NUM> and is operable, by tightening the fasteners <NUM>, to apply tension to the flexible covering <NUM> during anchoring.

In alternative embodiments, the fasteners <NUM> or other features may form part of the flexible covering <NUM> and be adapted to tighten onto the wall anchor system <NUM> to apply tension to the flexible covering <NUM>. Other means for connection may be used and, in some embodiments, one end region of the flexible covering <NUM> may be attached to the wall and tension is then applied at the opposite end region to create tension across the flexible covering <NUM>.

The wall anchor system <NUM> comprises two members, presently embodied by and hereinafter referred to as spines <NUM>, to attach to respective end regions <NUM> of the flexible covering <NUM>. The flexible covering <NUM> attaches to the wall <NUM> through or via the spines <NUM>, which are located at spaced apart locations <NUM>, <NUM> along the wall <NUM>. The end regions <NUM> of the flexible covering <NUM> each extend along an edge of the covering <NUM>. Accordingly, the members or spines <NUM> extend along opposite end regions <NUM>.

The spines <NUM> may be supplied in convenient lengths to simplify the installation. For example, the spines <NUM> may be supplied to have equal length to the end regions <NUM> - the length being evident as the elongate dimension of the spines <NUM> in <FIG>.

Each spine <NUM> is installed prior to the protective covering <NUM> and simplifies the installation thereof. The spine <NUM> may be installed after the layer of barrier material <NUM>, and/or after the layer of cloth or tape <NUM> is applied to the wall <NUM>. Therefore, layer <NUM> and/or layer <NUM> extend behind the spine <NUM>. To reduce wear of the layer <NUM> and/or <NUM>, which may otherwise occur as, for example, tidal forces batter the flexible covering <NUM> resulting in minor movements of the spine <NUM>, a flexible skirt <NUM> is installed between the spine <NUM> and the tape <NUM> as shown in <FIG>. This skirt <NUM> may be omitted but provides additional protection to the tape <NUM> in this area. The skirt <NUM> may be constructed of high density polyethylene with a thickness of around <NUM> and may be bonded to the spine <NUM> by plastic welding or other methods.

Referring to <FIG>, the spine <NUM> consists of a rigid material that may be high density polyethylene. The spine <NUM> is fastened to the sheet pile wall with mechanical fasteners <NUM> which pass through holes in the spine <NUM>, and holes in the skirt <NUM> if a skirt is used. In the preferred embodiment in <FIG>, the mechanical fasteners <NUM> are stud bolts that are welded to the sheet pile wall with nuts and washers to retain the spine <NUM>. Other methods of fastening may be used such as blind bolts installed into prepared holes in the sheet pile wall <NUM>, bolts into tapped holes or self-tapping screws. The fasteners are preferably constructed of a corrosion resistant material that is preferably marine grade stainless steel.

The spine <NUM> preferably bears against the wall <NUM> in water-tight engagement therewith. This is to prevent ingress of water, sand and contaminants behind the spine <NUM> and thus behind the flexible covering <NUM>.

Each spine <NUM> has angled faces <NUM>, <NUM>. Each angled face <NUM>, <NUM> is adapted to connect to a respective fixing portion of the flexible covering <NUM>. The angles of the angled faces <NUM>, <NUM> of the spine <NUM>, relative to the wall <NUM>, may be altered to suit the geometry of the particular sheet pile wall <NUM>, the angle at which the flexible covering <NUM> approaches the spine <NUM>, the type of fixing portion provided on the flexible covering <NUM> - e.g. flanges <NUM>, eyelets or a perforated metal band for receiving fasteners <NUM> or some other arrangement - and any other appropriate consideration. Similarly, the shape of the spine <NUM> may be changed to suit the application.

The protective covering <NUM> is fastened to the spine <NUM> at one end and to an adjacent or neighbouring spine <NUM> at its other end. A series of spines <NUM> and protective coverings <NUM> may, therefore, be used to provide corrosion protection along the length or area of the sheet pile wall <NUM> that is to be protected. A single spine <NUM> may provide one surface for attaching to one flexible covering <NUM>, and another surface for attaching to a neighbouring flexible covering <NUM>. Similarly, a vertical length of wall <NUM> can be protected by applying numerous lengths of the protection assembly <NUM>, in a horizontal orientation as shown in <FIG>. A small overlap between the flexible coverings <NUM> of vertically adjacent protection assemblies <NUM> may be used - this may warrant the lowermost fastener or fasteners of an upper flexible covering extending through the fixing portion of both the upper flexible covering and the flexible covering immediately below it. Similarly, numerous lengths of spine may also be used, preferably butting against one another.

The protective covering <NUM> is joined to the spine <NUM> by mechanical fasteners <NUM>. A plurality of fasteners <NUM> is associated with each spine <NUM>. The fasteners <NUM> are for attaching one of the fixing portions of the flexible covering <NUM> to the respective elongate member or spine <NUM> at spaced locations along the respective elongate member or spine <NUM>, as shown in <FIG>.

The fasteners <NUM> may form part of the wall anchor system <NUM>, or may form part of the flexible covering <NUM>, or both. The mechanical fasteners <NUM> may be integral with the wall anchor system <NUM> or flexible covering <NUM>. In the embodiment shown in <FIG>, the fasteners <NUM> extend or pass through holes in the fixing portions <NUM> to attach to the wall anchor system <NUM>. In the preferred embodiment in <FIG>, the mechanical fasteners <NUM> are stud bolts that are screwed or molded in the spine <NUM> and protrude out from the angled face of the spine <NUM>. Other methods of fastening the protective covering <NUM> to the spine <NUM> may be used including bolts that are screwed directly into the spine <NUM> or into threaded inserts embedded into the spine <NUM>. The threaded inserts may be moulded or screwed into the spine <NUM>, or retained by an appropriately shaped hole made in the face of the spine <NUM> that faces the surface of the sheet pile wall <NUM>. In this embodiment, a hole of diameter equal to, or slightly smaller than, the outer diameter of the threaded insert may be created in the face of the spine <NUM> facing the wall <NUM> in use. A smaller diameter hole, the diameter of which is approximately the outer diameter of the shank of a fastener <NUM>, may be bored through from one of faces <NUM>, <NUM> in coaxial alignment with the hole into which the threaded insert was installed. Thus, a fastener <NUM> subsequently inserted through face <NUM>, <NUM> can engage the threaded insert, yet the threaded insert is not susceptible to being pulled, by the bolt, out of the hole into which it is installed.

The embodiment described with reference to <FIG> involves a flexible covering <NUM> comprising a sheet <NUM>, and the integrity of the protection assembly relies on the sheet <NUM> being capable of maintaining tension while withstanding the environment <NUM>. In an alternative embodiment, in the protection assembly <NUM> of <FIG> the flexible covering <NUM> comprises straps <NUM>, and each of the fixing portions <NUM> comprises a respective one of two opposed ends of each strap <NUM>. In some embodiments, a single strap may be used and, in other embodiments, multiple straps may be used. In either case, the straps <NUM> may provide the entirety of the pressure or force across the flexible covering <NUM> towards the wall <NUM>, or the straps <NUM> and sheet <NUM> of the flexible covering <NUM> may both be placed under tension so as to provide that force.

Where multiple straps <NUM> are provided, the straps <NUM> may extend substantially in parallel across the flexible covering <NUM>. In particular, the straps <NUM> may extend between opposed end regions of the flexible covering <NUM>. The straps <NUM> may be spaced apart in a direction perpendicular to the direction of extension of the straps <NUM> - i.e. perpendicular to the direction extending between opposed ends of the straps <NUM> - with a fixing portion <NUM> being provided at each opposed end.

The straps <NUM> may directly retain the coating system <NUM> in position. However, for extra protection per the embodiment shown in <FIG>, the flexible covering <NUM> will include both a sheet <NUM> and straps <NUM> holding the sheet <NUM> to the coating system <NUM>. The straps <NUM> are then tensioned to apply at least a part of the force to press the coating system <NUM> towards or against the wall <NUM>. The straps <NUM> may instead provide all of the force, however, it is also envisaged that the sheet <NUM> may be independently tensioned, or tensioned with the straps <NUM>, so that the straps <NUM> and sheet <NUM> together apply the force to the coating system <NUM>.

Each strap <NUM> comprises two sections <NUM>, <NUM>, with a buckle <NUM> connecting the sections. The strap <NUM> is operable to draw at least one of the sections <NUM>, <NUM> through the buckle to apply tension to the strap <NUM>. Such mechanisms are well understood and need not be described in greater detail herein.

Since, in some embodiments, the sheet <NUM> is not attached to the outer face of the spine <NUM> for tensioning purposes, that sheet <NUM> may bunch up during tensioning. An angled section <NUM> may therefore be attached to, or be integral with, the spine <NUM> to overlap the sheet <NUM>. Thus, the end of the sheet <NUM> may be marginally shorter than the overall length of the straps <NUM> holding the sheet <NUM> to the coating system <NUM>.

In the embodiments shown in each of the figures herein, the flexible covering <NUM>, <NUM> may be tensioned by tensioning the fixing portions. In general, the fixing portion at one end of the flexible covering <NUM>, <NUM> will be tensioned in an opposite or divergent direction to the fixing portion at the opposite end of the flexible covering <NUM>, <NUM>. In other words, the force pulling the flexible covering <NUM> at one end thereof acts in an opposite or divergent direction to the force pulling the flexible covering <NUM> at the other end. This is to be contrasted with sheets covering cylindrical piles, where the ends of the sheet are attached to one another and thus the force applied at one end converges upon the force applied at the other end of the sheet.

Sheet pile walls often have protrusions or wall fittings on their outside face, such as the nuts and washers from tie-backs and fasteners for waling beams. Such nuts, washers and the like may be used to anchor the wall to the soil or another structure. In some embodiments, the flexible coverings <NUM>, <NUM> may be located so that the protrusions are within the depth of the shaping layer <NUM> and thus are neither exposed to the environment <NUM>, nor come into contact with the flexible covering <NUM>, <NUM>, which contact might other damage the covering <NUM>, <NUM>.

In other embodiments, a wall anchor system <NUM> may be located to pass through a protrusion or wall fitting such as shown in <FIG>. The protection assembly may therefore include means to cover or encase the wall fitting.

Regardless of where the wall fitting is located in the protection assembly, that assembly provides corrosion protection to the wall fitting while preventing damaging contact between the wall fitting and flexible covering or coating system as the case may be.

<FIG> show an exploded view of a protection assembly <NUM> applied to a sheet pile wall <NUM> with a fastener or wall fitting <NUM> on its outside face <NUM>. The fastener <NUM> is an example of a protrusion or wall fitting, consisting of a nut, washer and threaded bar, though other types of wall fitting are possible. The wall anchor system <NUM>, presently spine <NUM> and fasteners <NUM>, protective covering <NUM> and coating system <NUM> are trimmed to clear around the fastener <NUM>. Those same components may instead be shaped - during fabrication or afterward - to clear the fastener <NUM> prior to being brought to site. However, trimming to fit on-site would more readily allow for fault tolerance.

The wall anchor system <NUM>, protective covering <NUM> and coating system <NUM> may be cut in a circular fashion as shown, to provide clearance all around the fitting <NUM>. Alternatively, a square cut or other shape may be used to suit the particular wall fitting and construction of the protection assembly <NUM>. In any case, the protection assembly <NUM>, particularly the flexible covering <NUM>, is shaped to fit around the wall fitting or wall fittings.

An encasement <NUM> is then provided, to fit over the one or more fittings <NUM>. The encasement <NUM> is shaped to be received over the wall fitting or fittings <NUM> and over an outer surface of one or more of the components of the protection assembly, namely one or more of the flexible cover <NUM>, coating system <NUM> and wall anchor system <NUM>. To that end, the encasement <NUM> comprises a section <NUM> that is profile cut to match the profile of the outside of the protective cover <NUM>. The section <NUM> is then fit to the outer surface <NUM> of the protective cover <NUM>. A lid <NUM> is held onto the section <NUM> by nuts <NUM> and studs <NUM>, and tightening the nuts <NUM> pulls the section <NUM> against the protective cover <NUM>. The lid <NUM> thereby seals an internal volume of the section <NUM> against ingress of water, sand and other contaminants. <FIG> shows a circular shape of the section <NUM> but other shapes are possible, such as rectangular. Thus, the encasement <NUM> is fitted to the outer surface <NUM> of the protection assembly component, being the flexible covering <NUM>, wall anchor system <NUM> and/or coating system <NUM>.

Referring to <FIG>, the steel surface of the fastener <NUM> and surrounding surface of the sheet pile wall <NUM> are covered in the barrier material, e.g. anticorrosive gel <NUM>, and the cloth or tape <NUM>. Any gaps between the section <NUM> and the protective cover <NUM> or spine <NUM> may be filled with additional layers of tape <NUM> or other material. A compound <NUM> may then be used to fill the cavity made by, or volume of, the section <NUM> as seen in <FIG>. The compound may be a lightweight, thick waterproof gel. The compound may comprise anticorrosive gel and fillers, or another compound as required by a particular application.

It will be appreciated that other shapes of encasement <NUM>, profile cuts in the protection assembly <NUM>, and encasement fillers may be used without departing from the teachings herein.

With reference to <FIG>, the method <NUM> broadly describes the methods set out above for protecting a wall <NUM>. The method <NUM> comprises:.

In a specific embodiment of step <NUM>, and with reference to <FIG>, an anticorrosive gel <NUM> may be applied to the wall <NUM>. A layer of tape <NUM> made from a cloth or foam material impregnated with further anticorrosive gel is applied over the gel <NUM>. In deeply corroded and pitted areas as well as the joints <NUM> of the sheet pile wall <NUM> additional anticorrosive gel <NUM> or barrier material may be applied. Due to the volume, rather than a thin layer, that anticorrosive gel <NUM> is to occupy, anticorrosive gel <NUM> may have a formulation that is much stiffer than the gel <NUM> and may be reinforced with fibres or inert fillers. This additional gel is preferably applied before the tape <NUM>, gives the finished surface of the tape <NUM> a more uniform profile and ensures anticorrosive gel is kept in contact with the surface of the steel sheet pile <NUM> in these areas. Thus, barrier material in layer <NUM> may be different from barrier material at gel locations <NUM>.

As described above, the flexible covering <NUM> is anchored to the wall <NUM> in a tensioned condition. Since the flexible coating <NUM> is bent out of plane (e.g. follows a generally curved trajectory along the wall <NUM>), this tension ensures the flexible covering <NUM> produces a force acting towards the wall <NUM> to press the coating system <NUM> against the wall <NUM>. The flexible covering <NUM> may be tensioned during anchoring - e.g. by fasteners <NUM> pulling opposite ends of the flexible covering <NUM> away from each other during anchoring as discussed above - or may be tensioned before anchoring. For example, the flexible covering <NUM> may be pulled taut and then bolted onto wall anchor system <NUM>, or straps may be used that, when tightened, apply the necessary tension - the flexible covering <NUM> is thus properly anchored when the tension is applied by the straps.

Accordingly, in some embodiments the wall anchor system <NUM> applies the tension, in other embodiments the flexible covering <NUM> applies the tension and, in still further embodiments, both may apply a part of the tension. In some cases, anchoring the flexible covering <NUM> will involve tensioning the flexible covering <NUM> in divergent directions. With reference to <FIG>, the line of action of a force applied during tensioning one end of the flexible covering <NUM> onto one spine <NUM> (perpendicular to the surface of that spine <NUM>, abutting flexible covering <NUM>) acts towards the wall <NUM> in a direction divergent to that of the line of action of the force applied at the opposite end of the flexible covering <NUM>. Thus, the forces applied during tensioning are applied in divergent directions. This is to be contrasted with protection assemblies used to protected circular section steel piles, in which the two ends are brought together during tensioning and the forces applied to the opposite ends during tensioning converge.

The method <NUM> can be used to protect a wall <NUM>, that is elongate in a horizontal direction, from a marine environment. To facilitate this, the method <NUM> comprises installing a wall anchor system <NUM> across the wall <NUM>, i.e. in the direction of extension or elongation of the wall <NUM>, as shown in <FIG>. For each protection assembly <NUM>, the wall anchor system <NUM> comprises two elongate members or spines <NUM> spaced along the wall <NUM>, and a plurality of fasteners <NUM> associated with each elongate member or spine <NUM>. In use, step <NUM> comprises fixing the two elongate members or spines <NUM> to the wall <NUM> at spaced apart locations, and then fastening one of the fixing portions of the flexible covering <NUM> to each elongate member using a respective one of the pluralities of fasteners <NUM>.

Before attaching the spines <NUM>, the layers <NUM> and <NUM> of the coating system <NUM> will first be applied to the wall <NUM>. Then the spines <NUM>, including any skirt <NUM>, will be attached to the wall <NUM> through the layers <NUM>, <NUM>. The shaping layer <NUM> is then applied to the wall <NUM> between consecutive spines <NUM>, before the flexible covering <NUM> is attached to the spines <NUM>.

The method <NUM> can also be used to protect one or more wall fittings, such as fittings <NUM>. Thus, in addition to performing steps <NUM>, <NUM><NUM>, the method <NUM> may further comprise:.

The embodiments described herein may be used to protect a wall <NUM> from a marine environment. Since the wall is elongate in the horizontal direction - e.g. parallel to an horizon or parallel to a water surface of the marine environment, accepting that waves and disturbances may vary that surface from time to time - the wall cannot be protected using standard protection systems that wrap around the structure they seek to protect and fasten back onto themselves. Instead, the wall is protected using a protection assembly as described herein, with fixing portions being anchored at spaced apart locations in the horizontal direction of the wall <NUM>.

The protection assemblies <NUM> and methods for their use, as described herein may be used to protect elongate structures such as walls <NUM> located in marine environments. In some embodiments, the protection assemblies <NUM> may be applied to a sheet pile wall <NUM> which is composed of U-type sheet piles, combined wall composed of Z-type sheet piles or other structures of various and varying cross-section. The tension applied to the flexible covering <NUM> results from forces being applied at the wall anchor system <NUM>, to opposite end regions of the flexible covering <NUM>, in divergent directions. This cannot be achieved using protection assemblies designed to wrap around circular section piles and columns, which are able to clamp back onto themselves (i.e. where the opposite ends of the covering are brought together) to apply tension.

Throughout this specification and claims which follow, unless the context requires otherwise, the word "comprise", and variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated integer or group of integers or steps but not the exclusion of any other integer or group of integers. As used herein and unless otherwise stated, the term "approximately" means ±<NUM>%.

Claim 1:
A protection assembly (<NUM>, <NUM>) for protecting a wall (<NUM>), the wall (<NUM>) being one of: a sheet pile wall and a combined wall including sheet piles, the wall being elongate in a horizontal direction and having a non-planar profile such that an outer surface of the wall includes at least one of angles and changes in cross section, the protection assembly (<NUM>,<NUM>) comprising:
a coating system (<NUM>) for coating a portion of the wall (<NUM>);
a flexible covering (<NUM>, <NUM>) for covering the coating system (<NUM>), and having fixing portions at end regions of the flexible covering; and
a wall anchor system (<NUM>), wherein, in use,
the coating system (<NUM>) is located between the flexible covering and the wall (<NUM>),
the flexible covering is anchored, at the fixing portions, to the wall (<NUM>) by the wall anchor system (<NUM>);
characterized in that
the fixing portions are anchored to the wall (<NUM>) at spaced apart locations in the horizontal direction; and
the coating system (<NUM>) is shaped so that the flexible covering (<NUM>, <NUM>) follows a generally convex path between the fixing portions,
wherein the coating system (<NUM>) includes:
a barrier material layer (<NUM>) that is applied to an outer surface of the wall (<NUM>) in use; and
a shaping layer (<NUM>) disposed under pressure between the barrier material (<NUM>) and the flexible covering (<NUM>, <NUM>), the shaping material having a first side that faces the wall (<NUM>) in use and an opposing second side that is covered by the flexible covering (<NUM>, <NUM>) and that defines, between the fixing portions, a generally convex curve different from the wall profile, wherein the first side of the shaping layer (<NUM>) follows the non-planar profile of the wall (<NUM>) and accommodates the angles and/or changes in cross-section in the outer surface of the wall (<NUM>), such that the shaping layer (<NUM>) is shaped to remove voids between the flexible covering (<NUM>, <NUM>) and the barrier material (<NUM>), and
wherein the wall anchor system (<NUM>) is operable to apply tension to the flexible covering, so the flexible covering (<NUM>, <NUM>) is in hoop tension and produces a force to press the coating system (<NUM>) against the wall (<NUM>).