METHOD FOR FORMING A SHEET PILE STRUCTURE, SHEET PILE ELEMENT, SHEET PILE STRUCTURE AND USE OF A SHEET PILE STRUCTURE FOR DAMPING VIBRATION

TECHNICAL FIELD RELATED TO THE INVENTION

The invention relates to a method for forming a sheet pile structure, a sheet pile element, a sheet pile structure and to the use of a sheet pile structure for damp- ing vibration according to the preambles of the independent claims presented below.

PRIOR ART

Sheet pile elements and structures to be formed thereof are used in earthmo- ving for several different purposes, for example as support structures or head- works.

The patent publication WO00055433 discloses the manner in which a seam between two sheet pile elements can be sealed with concrete, for example. A broaching tool is arranged in connection with the element, which tool forms a cavity when installing an element in the ground and into which cavity concrete is fed at the same time as the element is installed in the ground, whereby the soil possibly loosening from the edges of the cavity does not have time to fill the formed cavity before concrete is fed.

Vibration in the earth for example in conjunction with railways and heavily traffi- cated roads, in particular in clay ground, disturbs the inhabitants of the neighbouring areas and can also damage the constructions in the neighbouring areas. To solve the problem, for example, sheet piles of steel installed obliquely in the earth have been suggested. The purpose is to get some of the shock waves to travel in an angle according to the direction of the sheet pile element to the surface of the ground, whereby the propagation of the vibration in the

earth can partly be disrupted. A plate-like sheet pile of steel does not usually in addition to reflection significantly absorb shock waves.

PURPOSE AND DESCRIPTION OF THE INVENTION

The purpose of this invention is to reduce or even completely eliminate problems or disadvantages related to prior art.

The purpose of this invention is to provide a solution by means of which the damping of vibration in the soil is more effectively performed than by means of solutions of prior art.

The purpose of this invention is also to provide an alternative solution for arranging a concrete element into the soil.

Among other things in order to attain these purposes mentioned above the method for forming a sheet pile structure, a sheet pile element, a sheet pile structure and the use of a sheet pile structure for damping vibration according to the invention is characterised in what is presented in the characterising parts of the enclosed independent claims.

The embodiments mentioned in this text apply where applicable to a method for forming the sheet pile structure, a sheet pile element, a sheet pile structure as well as the use of a sheet pile structure for damping vibration although this is not always specifically mentioned.

In a typical method according to the invention for forming a sheet pile structure

- a broaching tool is fastened in connection with the lower edge of a sheet pile element, - a grout hose is detachably fastened in connection with the sheet pile element with the aid of a hose fastening means,

- the sheet pile element is arranged in the soil the lower edge and broaching tool first, whereby the broaching tool forms a cavity in the soil,

- in the cavity formed by the broaching tool concrete grout is fed at the same time as the sheet pile element is arranged in the soil in such a manner that said cavity is at least partly filled with concrete grout,

- the hose fastening device is released and the grout hose is disconnected from being in connection with the sheet pile element after the sheet pile element is arranged at a desired depth inside the soil.

In the method the width of said broaching tool and the width of the cavity formed by means said tool is at least 30 % of the width the sheet pile element, whereby the concrete grout fed into the cavity covers at least 30 % of the surface of the sheet pile element. According to an embodiment the width of the formed cavity is 40 - 80 %, according to another embodiment 30 - 100 % and according to yet another embodiment 30 - 120 % of the width of the sheet pile element. When the broaching tool is wider than the sheet pile element a tight seam enclosed by concrete is achieved between two sheet pile elements to be installed adjacent to each other.

In connection with a typical sheet pile element according to the invention a broaching tool is arranged for forming a cavity into the soil, as well as a hose fastening means for the grout hose. The width of the broaching tool is at least 30 % of the width of the sheet pile element.

By a broaching tool a means fastened in connection with the sheet pile element, typically in connection with its lower edge, is meant, the purpose of which means is to form a cavity in the soil at the same time as the sheet pile element is installed in the ground. The broaching tool can be a wedge-shaped means or a means shaped from the top like an open box. The broaching tool is advantageously shaped in such a manner that between it and the soil such small a resistance is formed as possible, when the broaching tool is pushed into the soil. The cavity is formed in order to be able to feed concrete grout into it, whereby a concrete layer or concrete coating is formed in connection with the sheet pile element. The cavity is advantageously substantially completely filled with concrete grout. Very advantageously the broaching tool is arranged to form a cavity on both sides of the sheet pile element that is in connection with both of the

large surfaces, however, the cavity can also be arranged on only one side of an element that is only in connection with one large surface.

By the width of the broaching tool the measure is meant, how wide a cavity it forms when arranged into the soil. The width of the broaching tool is parallel to that of the sheet pile element. According to an embodiment of the invention the width of the broaching tool is at least 30 % of the width of the lower edge of the sheet pile element.

Depending on the shape and width of the broaching tool the large surfaces of the sheet pile element can be completely or partly coated with a concrete layer.

In one sheet pile element several, for example two, three or four broaching tools can be arranged, in which case the width of the broaching tool refers to the total width of the broaching tools arranged in one sheet pile element.

A sheet pile element refers to a single sheet pile element installed in the ground or to a structure formed of two or more sheet pile elements, such as a sheet piling or the like. A typical sheet pile structure according to the invention is formed by the method disclosed in this application.

Sheet pile elements can be formed from steel, concrete, wood or composite materials. A plate-like sheet pile element of steel is particularly well-suited for the applications of this invention. A part of the plate-like sheet pile elements are substantially even and rectangular in shape. Sheet pile elements comprising at least one bent corner are very commonly used, and they are thus not planar plates. Also bent elements are well suited to be used in solutions according to the invention disclosed in this application. A typical plate-like sheet pile element comprises a first and second large surface, an upper and a lower edge as well as a first and a second edge, which edges can, for example, be on the left and on the right.

By the width of the sheet pile element the width of one large surface is meant that is the measure between the first and second edge measured along the large surface of the element. Thus, the width is not a straight measure, if the sheet pile element comprises folds and even surfaces separated by these but the total width of the surfaces is to be measured along the surface of the element. If the sheet pile element is a round pipe, by the width the outer diameter of the pipe is meant.

In this application concrete grout and concrete is used as general terms and they refer to hydraulically hardening grouts and plasters, in which in addition to cement other binders can be used, such as slag.

By a grout hose a means for feeding the concrete grout is meant and in addition to a flexible hose it can also be a rigid pipe, for example. The feeding head of the grout hose refers to that end from which the concrete grout exits for example into the cavity formed by the broaching tool.

By the hose fastening means a means is meant with the aid of which the grout hose can be fastened in connection with the sheet pile element. Fastening the grout hose detachably refers to the fact that the fastening can be opened. The fastening is typically arranged in such a manner that it can be opened at ground level for example by pulling a wire after the sheet pile element is installed in the ground and the hole formed by the broaching tool is substantially fully fed of concrete grout.

The soil can for example be gravel, sand, clay, topsoil or a mixture of these. Installing the sheet pile in the ground or earth refers to in this application the same as installing the sheet pile in the soil.

According to an embodiment of the invention the broaching tool is detachably fastened to the lower edge of the sheet pile element. Thus, the second sheet pile element to be installed later in the ground or the broaching tool fastened thereto can push or hit and thereby release the broaching tool detachably fas-

tened in connection with the sheet pile element previously installed in the ground. This is useful when the broaching tool is wider than the sheet pile element or if the broaching tools of adjacent elements otherwise hit each other when installing. By using the detachable broaching tool, cutting the corners of sheet pile elements or additional designing of the broaching tools hitting each other can be avoided.

According to an embodiment of the invention a second sheet pile element is installed in connection with the sheet pile element previously installed in the soil in such a manner that the lock tool of the second sheet pile element is arranged into the lock tool of the sheet pile element previously installed in the soil.

The lock tool can be for example a fold or a rail-formed or tubular member arranged in the first and second edge of the sheet pile element for fastening two sheet pile elements to each other.

For example in the vicinity of railways and highways vibration occurs, which is desired to be dampened, as this vibration may cause damage to different structures such as the foundations of houses.

The sheet pile structure manufactured according to the method disclosed in this application is particularly well-suited for dampening vibration in the soil.

A massive element, such as a sheet pile element at least partly coated with concrete or a sheet piling structure formed of several of those according to the invention dampens vibration in soil better than a sheet pile element made of a steel plate alone.

According to an embodiment of the invention the concrete grout fed into the cavity formed by the broaching tool in connection with the sheet pile element is arranged to form a patterned concrete layer differing from an even surface. By forming a winding sheet piling or other sheet pile structure having a shape differing from the even wall surface the dampening of vibration in soil can be made

more effective as compared to a smooth or flat sheet piling. For example a cogged, serrated or otherwise patterned concrete layer is achieved for example by means of different broaching tool shapes. The shape of the wall surface or structure can also be affected among other things through the installing position and direction of the sheet pile elements in the soil.

An advantage of the invention is that by using the method according to the invention a concrete wall or structure can be formed in the soil very conveniently without having to excavate the ground.

An advantage of the invention is that the concrete layer protects the sheet pile element against corrosion, in particular if the element is substantially completely coated with concrete, whereby the width of the broaching tool is typically 100 % of the width of the sheet pile element or wider than that.

By arranging a concrete layer in connection with the sheet pile element according to the invention a structure is achieved which is more supportive than a simple plate-like sheet pile element.

BRIEF DESCRIPTION OF THE FIGURES

The invention is described in more detail below with reference to the enclosed schematic drawing, in which

Figure 1 shows a sheet pile element 1 according to prior art, Figure 2 shows a rectangular even plate-like sheet pile element according to prior art,

Figure 3 shows a sheet piling according to prior art, which is formed of three bent sheet pile elements,

Figure 4 shows a sheet pile element according to a first embodiment of the invention in a perspective view,

Figure 5 shows a part of the sheet pile element of figure 4 as seen from the direction of its first edge,

Figure 6 shows a broaching tool of figure 4 as seen from the direction of the upper edge of the sheet pile element,

Figure 7 shows a sheet pile element according to a second embodiment of the invention, Figure 8 shows a sheet pile element according to a third embodiment of the invention,

Figure 9 shows a sheet piling formed of five next to each other installed sheet pile elements,

Figure 10 shows a sheet piling formed of three bent sheet pile elements, Figure 11 shows a sheet piling installed in the ground according to figure 10 as seen from above,

Figure 12 shows a sheet piling installed in the ground according to figure 9 as seen from above,

Figure 13 shows four sheet pile elements, three of which are installed in the ground and the fourth element is being installed in connection with the third,

Figure 14 shows a sheet piling in a cross-section from the direction of ground level, and

Figure 15 shows a patterned concrete layer arranged in connection with the sheet pile elements, which layer comprises pocket-like spaces.

DETAILED DESCRIPTION OF THE EXAMPLES OF THE FIGURES

Figure 1 shows a sheet pile element 1 according to prior art. This element 1 is a plate-like piece formed of steel comprising two bent corners 2a, 2b and thus three even surfaces that is planes 3a, 3b, 3c. The sheet pile element 1 comprises an upper edge 4 and a lower edge 5, a first 6 and a second 7 edge as well as regarding its surface area the largest first 8 and second large surfaces both comprising three planes. The second large surface is left behind the sheet pile element 1 in the figure.

Figure 2 shows the rectangular even plate-like sheet pile element 1 according to prior art, in which element the first 6, second 7 and the upper 4 and lower edges 5 as well as the first large surface 8 are marked.

Figure 3 shows a sheet piling 11 according to prior art, which is formed of three bent sheet pile elements 1a, 1b, 1c, which are fastened in connection with each other by means of lock tools 15.

Figure 4 shows a sheet pile element 1 according to the first embodiment of the invention in a perspective view. The sheet pile element of this example is a plate-like rectangular piece and in connection with its lower edge 5 a broaching tool 14 is detachably fastened with the aid of a broaching tool fastening means 13. The shape of the broaching tool 14 is such that it displaces soil to the side and forms a cavity around the sheet pile element 1 , when the sheet pile element is arranged in the soil. Typically the sheet pile element 1 is arranged in the ground the lower edge 5 and the broaching tool 14 fastened thereto first, for example, by beating, pushing, ramming or by otherwise exerting force to the upper edge 4 of the sheet pile element. A grout hose 17 is detachably fastened in connection with the first large surface 8 of the sheet pile element and especially the broaching tool 14 with the aid of a hose fastening means 19. Correspondingly, in connection with the second large surface of the sheet pile element that is on the other side of the element in the figure a second grout hose 18 is fastened. Very advantageously the grout hose 17 is fastened in connection with the broaching tool 14 in such a manner that its feeding head 16 is protected by the broaching tool in order to be able to feed concrete into the cavity formed by the broaching tool at the same time as the sheet pile element 1 is arranged in the soil. In this manner the cavity can be filled with concrete before any possible loose soil reaches the cavity from its edges. The feeding head 16 is visible in the figure although in reality it is left hidden behind the edge of the broaching tool 14. The hose fastening means 19 is released and the grout hose 17 and the second grout hose 18, respectively, is disconnected from being in connection with the sheet pile element 1 after the sheet pile element is arranged at a desired depth inside the soil. In this manner the grout hoses 17, 18 can be reused and remarkable savings in material are achieved. In this example the width of the broaching tool is about 100 % of the width of the sheet pile element.

The width of the sheet pile element refers to the distance w1 between the first 6 and the second 7 edge.

Figure 5 shows a part of the sheet pile element 1 of figure 4 as seen from the direction of its first edge 6. The broaching tool 14 is wedge-shaped, substantially V-shaped regarding its cross section. The broaching tool 14 is fastened to the sheet pile element 1 with the aid of a broaching tool fastening means, which in this example is formed by two plate-like pieces 13a, 13b, between which the plate-like sheet pile element 1 is arranged. Before fastening the broaching tool 14 to the sheet pile element 1 the gap between the plate-like pieces 13a, 13b is substantially as large as or advantageously somewhat smaller than the thickness z of the sheet pile element. When the lower edge of the plate-like sheet pile element 1 is arranged between the plate-like pieces 13a, 13b, the pieces yield away from each other and at the same time they are pressed against the sheet pile element 1 , whereby friction holds the broaching tool 14 in contact with the sheet pile element 1. The broaching tool 14 can, however, easily be detached from being in connection with the sheet pile element 1 by exerting a force on the broaching tool approximately in the direction of the arrow y.

Figure 6 shows the broaching tool 14 of figure 4 as seen from the direction of the upper edge 4 of the sheet pile element 1. The broaching tool fastening means is formed of two pieces 13a, 13b, between which the sheet pile element 1 is partly arranged. The thickness of the sheet pile element 1 is marked with the letter z. The figure also shows two grout hoses 17, 18 and their fastening means 19, 20.

The figure 7 shows the sheet pile element 1 according to the second embodiment of the invention, the width w2 of the broaching tool 14 arranged in connection with which element is about 50 % of the width w1 of the sheet pile element. The advantage of this solution is that while installing sheet pile elements next to each other the broaching tools do not hit each other. On the other hand it is not a problem if the broaching tools hit each other when using a solution according to an advantageous embodiment of the invention in which the sheet pile ele-

merit to be installed later pushes or hits away the detachably fastened broaching tool in connection with the sheet pile element previously installed in the soil.

Figure 8 shows the sheet pile element 1 according to the third embodiment of the invention, the width w3 of the lower edge of the broaching tool arranged in connection with which element is approximately the same as the width of the sheet pile element and the width w4 of the upper edge of the broaching tool is about 30 % of the width w1 of the sheet pile element. This broaching tool 14 forms a cavity when arranged in the soil, which cavity in the immediate vicinity of the large surfaces of the sheet pile element is as wide as the sheet pile element and which cavity narrows when moving away from the large surfaces of the sheet pile element.

Figure 9 shows the sheet piling formed of five next to each other installed sheet pile elements. The first 6 and second 7 edge of each sheet pile element that is in the situation of the figure show lock tools 15 in the left 6 and right edges 7, by means of which tools the adjacent sheet pile elements are fastened to each other. The figure does not show any concrete, which usually in this situation is fed in connection with the sheet pile elements in such a manner that the con- crete layer would substantially cover the sheet pile elements completely or at least regarding its entire width. The width of the broaching tools is about 100 % of the width of the sheet pile elements.

Figure 10 shows the sheet piling 11 formed of three bent sheet pile elements 1a, 1 b, 1c. Adjacent sheet pile elements 1a, 1 b, 1c are fastened to each other by means of lock tools 15. Each sheet pile element 1a, 1b, 1c comprises two bent corners 2a, 2b and thus three planes that is even surfaces 3a, 3b, 3c. There is in connection with each plane a separate broaching tool 14 of its own. Each broaching tool 14 is as wide regarding its base w3 as the width wθ of one plane of the sheet pile element. The width w4 of the broaching tools at their upper edges is about 50 % of the width wθ of one plane. In this case the width of the sheet pile element refers to the width of three planes that is three times wθ, as each sheet pile element 1a, 1 b, 1c of the example comprises three planes.

Correspondingly, the width of the broaching tool refers to the sum of the widths of the broaching tools installed in one sheet pile element. Tapering broaching tools according to this example fit next to each other without hitting each other when the sheet pile elements are installed adjacently. Even in this picture the concrete fed in connection with the sheet pile elements 1 a, 1 b, 1 c is not shown.

Figure 11 shows the sheet piling 11 installed in the ground according to figure 10 as seen from above. The sheet piling comprises of three sheet pile elements 1a, 1 b, 1c, each of which have two bent corners and thus three planes that is even surfaces. The sheet pile elements 1 a, 1b, 1c are enclosed by a concrete layer 21 regarding an area, which is shaped like the cavities formed by the broaching tools. The figure also shows the lock tools 15 between the elements.

Figure 12 shows a sheet piling according to figure 9 installed in the ground as seen from above. The wall comprises five sheet pile elements 1 , which are fastened in connection with each other by means of lock tools 15. The sheet pile elements and thus the entire wall is enclosed by the concrete layer 21 formed according to the invention of this application. The thickness x of the concrete layer 21 is affected by the shape of the broaching tool. The thickness of the concrete layer can be for example 1 - 20 cm, 1 - 15 cm, 1 - 10 cm, 1 - 5 cm or 1 - 3 cm.

Figure 13 shows four sheet pile elements 1a - 1d, three 1a - 1c of which are installed in the ground and the fourth element 1d is being installed in connection with the third 1c. In this example the width of the broaching tool is about 110 - 120 % of the width of the sheet pile element. Therefore, the element 1d to be installed in the ground later or its broaching tool 14d pushes away the adjacent detachably fastened broaching tool 14c in the element 1c previously installed in the ground. The broaching tools 14a, 14b of the first two elements 1a, 1 b are detached.

Figure 14 shows a sheet piling as a cross section from the direction of ground level, the large surfaces 8a - 8c, 9a - 9c of sheet pile elements of which sheet

piling are coated with concrete 21. Such a structure can be used for example as a support structure. Lock tools 15 keep the adjacent sheet pile elements in connection with each other.

In figure 15 a patterned concrete layer 21 is arranged in connection with the sheet pile elements 1a - 1c with the method of the invention and by means of broaching tools with suitable shapes, which layer comprises pocket-like spaces and absorbs vibration in soil very well. The cross section of the sheet piling of the figure is shown from the direction of ground level and the upper edge of the sheet pile elements.

Although different figures show different examples of the invention, the same reference numbers have been used of some of the corresponding but still different parts for the sake of clarity. For the sake of clarity of the drawings the broaching tool extends in several figures further from the surface of the sheet pile elements than in practice. The invention is not meant to be limited to the embodiments shown as examples above but, on the contrary, the aim is to apply it extensively within the scope of protection defined in the claims below.