JP7846342B2 - Steel sheet pile connecting structure, steel sheet pile connecting method, and steel sheet pile structure - Google Patents

Description

This invention relates to a connecting structure for steel sheet piles, a method for connecting steel sheet piles, and a steel sheet pile structure.

Steel sheet piles are widely used in civil engineering and construction projects to build steel sheet pile walls for earth retention and waterproofing. For example, under bridge girders, when the required length of steel sheet piles is limited by the height of the construction space, multiple steel sheet piles are connected longitudinally and driven into the ground. However, when steel sheet piles are joined together by on-site welding, as was done conventionally, the welding process takes a long time, resulting in a lengthy overall construction period.

Therefore, Patent Document 1 proposes a technique for mechanically connecting steel sheet piles in the longitudinal direction by fixing reinforcing steel plates protruding from the surface of the steel sheet piles together using bolts and nuts. This eliminates the need for on-site welding to connect the steel sheet piles, thus shortening the construction period. Furthermore, Patent Document 1 also describes how to suppress the increase in driving resistance by arranging the reinforcing steel plates so that they fit within the wall thickness range of the steel sheet pile wall.

Furthermore, Patent Document 2 proposes a joint structure for mechanically connecting a first steel sheet pile and a second steel sheet pile in the longitudinal direction, while minimizing the height at which the member protrudes from the surface of the steel sheet pile. This joint structure includes a first uneven portion formed on the side surface of the first steel sheet pile, and a plate-shaped connecting member extending along the sides of both the first and second steel sheet piles and engaging with the first uneven portion.

Japanese Patent Publication No. 2011-38288 Japanese Patent Publication No. 2019-31829

Although the technology described in Patent Document 2 is an improvement over the technology described in Patent Document 1, a certain amount of dimensional margin is necessary for smooth engagement of the uneven parts. This, in turn, could lead to looseness and a decrease in apparent rigidity, or cause force to concentrate on specific parts of the uneven areas, potentially resulting in deformation or damage. Therefore, there was still room for improvement.

Therefore, the present invention aims to provide a steel sheet pile connecting structure, a steel sheet pile connecting method, and a steel sheet pile structure that can transmit force more stably between connected steel sheet piles while suppressing the height at which members protrude from the surface of the steel sheet pile.

[1] A connecting structure for connecting first and second steel sheet piles at their longitudinal ends, comprising: a first protruding member that protrudes from the side surface of the first steel sheet pile at its longitudinal end and has a first contact surface directed toward the longitudinal center of the first steel sheet pile; a second protruding member that protrudes from the side surface of the second steel sheet pile at its longitudinal end and has a second contact surface directed toward the longitudinal center of the second steel sheet pile; and a connecting member having a third contact surface that contacts the first contact surface and a fourth contact surface that contacts the second contact surface, and having a shape that at least partially surrounds the first protruding member and the second protruding member in a cross section parallel to the sides of the first and second steel sheet piles.
[2] The connecting member has a closed shape that surrounds the entire circumference of the first and second protruding members in a cross section parallel to the side surfaces of the first and second steel sheet piles, as described in [1].
[3] The connecting structure according to [2], wherein the first and second contact surfaces have a taper formed in a cross section that includes the longitudinal direction of the first and second steel sheet piles and is perpendicular to the side surfaces of the first and second steel sheet piles, becoming narrower as it moves away from the first and second steel sheet piles.
[4] The connecting structure according to [2] or [3], wherein the overall shape of the first and second protruding members in a cross section parallel to the side surfaces of the first and second steel sheet piles is rectangular, hexagonal, hourglass-shaped, or elliptical.
[5] The connecting structure according to any one of items [2] to [4], further comprising the connecting member or a lid member joined to the connecting member and fixing bolts inserted through the first and second protruding members.
A method for connecting steel sheet piles using the connecting structure described in any one of paragraphs [6], [2] to [5], comprising the steps of: joining the first protruding member to the side surface of the first steel sheet pile; joining the second protruding member to the side surface of the second steel sheet pile; butting the first steel sheet pile and the second steel sheet pile at their longitudinal end faces; and fitting the connecting member to the first and second protruding members from the side opposite to the sides of the first and second steel sheet piles, bringing the third contact surface into contact with the first contact surface and the fourth contact surface into contact with the second contact surface.
[7] The connecting member has an open shape in a cross section parallel to the sides of the first and second steel sheet piles, and does not surround one of the side end faces of the first and second protruding members, as described in [1].
[8] The connecting structure according to [7], wherein the first and second contact surfaces have a taper formed in a cross section that includes the longitudinal direction of the first and second steel sheet piles and is perpendicular to the side surfaces of the first and second steel sheet piles, becoming narrower as they approach the first and second steel sheet piles.
[9] The connecting structure according to [7] or [8], wherein the first and second contact surfaces have a taper formed in a cross section parallel to the sides of the first and second steel sheet piles, becoming narrower as it moves away from the side end surface that is not surrounded by the connecting member.
[10] The connecting structure according to any one of items [7] to [9], further comprising fixing bolts inserted through the first and second protruding members and the connecting member.
A method for connecting steel sheet piles using the connecting structure described in any one of items [11], [7] to [10], comprising the steps of: joining the first protruding member to the side surface of the first steel sheet pile; joining the second protruding member to the side surface of the second steel sheet pile; butting the first steel sheet pile and the second steel sheet pile at their longitudinal end faces; and fitting the connecting member to the first and second protruding members from a direction parallel to the side surfaces of the first and second steel sheet piles, bringing the third contact surface into contact with the first contact surface and the fourth contact surface into contact with the second contact surface.
A steel sheet pile structure comprising a connecting structure as described in any one of paragraphs [12], [1] to [5], or [7] to [10], wherein the first and second steel sheet piles are hat-shaped steel sheet piles, and the connecting structure is attached to at least one side of the web, arm, or flange of the hat-shaped steel sheet pile.
[13] The steel sheet pile structure according to [12], wherein the connecting structure is attached to both sides of the first and second steel sheet piles by the web and the arm.

According to the above configuration, the connecting member has a shape that surrounds the protruding member in a cross-section parallel to the side surface of the steel sheet pile, thereby reducing the height at which the connecting structure's members protrude from the surface of the steel sheet pile. Furthermore, by transmitting force between the protruding member and the connecting member through a pair of contact surfaces on each side of the connected steel sheet pile, force is not concentrated on specific parts of the dispersed contact surfaces, allowing for stable force transmission.

This is a perspective view showing a part of a steel sheet pile wall including a connecting structure according to the first embodiment of the present invention. This is an enlarged view of the connecting structure in Figure 1. This diagram shows the formation process of the connecting structure shown in Figure 2, and corresponds to the cross-sectional view taken along line III-III in Figure 2. This figure shows a modified example of the example shown in Figure 3. This figure shows an example of the planar shape of a connecting structure according to the first embodiment of the present invention. This figure shows an example of how to attach the connecting structure according to the first embodiment of the present invention to a steel sheet pile wall. This figure shows an example of a detachment prevention structure in a connecting structure according to the first embodiment of the present invention. This is a perspective view showing a part of a steel sheet pile wall including a connecting structure according to a second embodiment of the present invention. This diagram shows the formation process of the connecting structure shown in Figure 8, and corresponds to the view along the line IX-IX in Figure 8. This figure shows the formation process of the connecting structure shown in Figure 8.

Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. In this specification and the drawings, components having substantially the same functional configuration are denoted by the same reference numerals, thus omitting redundant descriptions.

Figure 1 is a perspective view showing a part of a steel sheet pile wall including a connecting structure according to a first embodiment of the present invention, and Figure 2 is an enlarged view of the connecting structure in Figure 1. As shown in Figures 1 and 2, the steel sheet pile wall 1 connects a plurality of hat-shaped steel sheet piles 10 in the longitudinal direction (z direction in the figure) by a connecting structure 20, and also connects them in the width direction (x direction in the figure) by connecting joints 11 formed on both sides. Each steel sheet pile 10 includes a web 12, a flange 13, and an arm 14. In the following description, the surfaces of the steel sheet pile 10 that do not constitute these parts, other than the end faces, are referred to as the side faces of the steel sheet pile 10. In the web 12 and arm 14, the side faces of the steel sheet pile 10 are the surfaces facing the wall thickness direction (y direction in the figure) of the steel sheet pile wall. Similarly, the surfaces of the steel sheet pile 10 facing the longitudinal direction (z direction) are referred to as the end faces of the steel sheet pile 10. Note that the x, y, and z directions are common in the figures described below. Furthermore, while the steel sheet pile 10 in the illustrated example is a hat-shaped steel sheet pile, the connecting structure according to the embodiment of the present invention can be applied to steel sheet piles of various cross-sections, such as U-shaped steel sheet piles, Z-shaped steel sheet piles, and straight steel sheet piles.

More specifically, the connecting structure 20 includes a protruding member 21A (first protruding member) that protrudes from the side surface of the web 12 at the longitudinal end of the steel sheet pile 10A, a protruding member 21B (second protruding member) that protrudes from the side surface of the web 12 of the steel sheet pile 10B at the longitudinal end of the steel sheet pile 10B, and a connecting member 22 that fits into the protruding members 21A and 21B. The protruding members 21A, 21B, and the connecting member 22 are steel plate-shaped members having the shapes described below. In this embodiment, the connecting member 22 has a closed shape that surrounds the entire circumference of the protruding members in a cross-section parallel to the sides of the steel sheet piles 10A and 10B (the x-z cross-section in the figure).

Figure 3 is a diagram showing the formation process of the connecting structure shown in Figures 1 and 2, and corresponds to the cross-sectional view taken along line III-III in Figure 2. As shown in the figure, the connecting structure 20 is formed, for example, by first joining protruding members 21A and 21B to steel sheet piles 10A and 10B by welding or the like, butting the end faces of the steel sheet piles 10A and 10B in the longitudinal direction, and then fitting the connecting member 22 onto the protruding members 21A and 21B from the side opposite to the sides of the steel sheet piles 10A and 10B. The protruding member 21A has a contact surface 211A (first contact surface) directed toward the longitudinal center side of the steel sheet pile 10A (i.e., opposite to the longitudinal end), and the protruding member 21B has a contact surface 211B (second contact surface) directed toward the longitudinal center side of the steel sheet pile 10B. On the other hand, the connecting member 22 has contact surfaces 221A (third contact surface) and 221B (fourth contact surface) that face each other inside the closed shape that surrounds the entire circumference of the protruding members 21A and 21B as described above. The contact surface 221A of the connecting member 22 contacts the contact surface 211A of the protruding member 21A, and the contact surface 221B contacts the contact surface 211B of the protruding member 21B. This transmits bearing pressure between the respective contact surfaces, allowing the connecting structure 20 to function as a connecting part capable of transmitting tensile force between the steel sheet piles 10A and 10B. Regarding compressive force, if the horizontal position of the steel sheet piles 10A and 10B is fixed by the connecting structure 20, it is transmitted by the contact between the end faces of the steel sheet piles 10A and 10B; therefore, it does not necessarily need to be transmitted by the connecting structure 20.

In the illustrated example, the contact surfaces 211A and 211B of the protruding members 21A and 21B have a taper that narrows as it moves away from the steel sheet piles 10A and 10B in a cross-section (y-z cross-section in the figure) that includes the longitudinal direction of the steel sheet piles 10A and 10B and is perpendicular to the side surfaces of the steel sheet piles 10A and 10B. That is, in the above cross-section, the protruding members 21A and 21B, including the contact surfaces 211A and 211B, are trapezoidal as a whole, with the steel sheet piles 10A and 10B as the base. The contact surfaces 221A and 221B of the connecting member 22 have a shape corresponding to the contact surfaces 211A and 211B in order to contact the contact surfaces of the protruding members 21A and 21B. That is, in the above cross-section, the space enclosed by the inner contact surfaces 221A and 221B of the closed shape of the connecting member 22 expands toward the steel sheet piles 10A and 10B.

As described above, by making the contact surfaces of the protruding members 21A, 21B and the connecting member 22 tapered and opening toward the sides of the steel sheet piles 10A, 10B, dimensional errors in the protruding members 21A, 21B and the connecting member 22, as well as errors in the mounting position of the protruding members 21A, 21B to the steel sheet piles 10A, 10B, can be absorbed, allowing the contact surfaces 211A, 211B of the protruding members 21A, 21B and the contact surfaces 221A, 221B of the connecting member 22 to come into contact without any gaps.

Figure 4 shows a modified example of the example shown in Figure 3. In the longitudinal cross-section of the protruding members 21A, 21B and the connecting member 22, the contact surfaces do not necessarily have to be tapered; as shown in the example in Figure 4, the contact surfaces may be approximately parallel. In this example, the contact surfaces 211A and 211B of the protruding members 21A and 21B are both inclined upwards in a cross-section (y-z cross-section in the figure) that includes the longitudinal direction of the steel sheet piles 10A and 10B and is perpendicular to the sides of the steel sheet piles 10A and 10B. That is, in the cross-section of Figure 4, the protruding members 21A and 21B, including the contact surfaces 211A and 211B, are approximately parallelograms. Note that the contact surfaces do not need to be strictly parallel; it is sufficient that the contact surfaces that come into contact with each other, i.e., contact surfaces 211A, 221A and contact surfaces 211B, 221B, are formed with corresponding inclinations.

If the contact surfaces of the protruding members 21A, 21B and the connecting member are not tapered, a small gap is required between the contact surfaces 211A, 211B of the protruding members 21A, 21B and the contact surfaces 221A, 221B of the connecting member 22 to absorb positional errors in the upper and lower sheet piles during construction, as well as dimensional and mounting position errors. This causes rattling between the members, but when the connecting structure 20 transmits tensile force between the steel sheet piles 10A, 10B, the protruding members 21A, 21B are pulled in opposite directions, eliminating the gap between the contact surfaces. Therefore, the connecting structure 20 functions even with such a gap. Furthermore, as shown in the example in Figure 4, if the contact surface is inclined upwards, gravity acting on the connecting member 22 can be used to prevent the connecting member 22 from detaching from the protruding members 21A and 21B. As shown in Figures 7(b) and 7(c) later, when the connecting member is fixed to the protruding members using fixing bolts, the upper bolt can be eliminated, and the connection can be made using only the lower bolt, reducing processing costs and bolt installation work. The contact surface may be perpendicular to the sides of the steel sheet piles 10A and 10B, or it may be inclined downwards. In these cases as well, detachment of the connecting member 22 can be prevented by means such as fixing bolts, as described later.

Figure 5 shows an example of the planar shape of a connecting structure according to the first embodiment of the present invention. The planar shape of the connecting structure, that is, the overall shape of the protruding members 21A and 21B in a cross-section parallel to the sides of the steel sheet piles 10A and 10B (the x-z cross-section in the figure), may be rectangular as shown in Figure 2, hexagonal as shown in Figure 5(a), hourglass-shaped as shown in Figures 5(b) and 5(c), or elliptical as shown in Figure 5(d). In any case, the protruding members 21A and 21B each have contact surfaces directed toward the longitudinal center of the steel sheet piles 10A and 10B. Note that, for example, as shown in Figures 5(a) and 5(d), the contact surface does not necessarily have to be a surface perpendicular to the longitudinal direction of the steel sheet piles 10A and 10B in the above cross-section; it may be an inclined or curved surface such that the bearing pressure transmitted through the contact surface includes a component in the longitudinal direction of the steel sheet piles 10A and 10B.

In each of the above examples, the closed shape formed on the inside by the connecting member 22 corresponds to the overall planar shape formed by the protruding members 21A and 21B. Specifically, the closed shape formed on the inside by the connecting member 22 is rectangular in the example of Figure 2, hexagonal in the example of Figure 5(a), hourglass-shaped in the examples of Figures 5(b) and 5(c), and elliptical in the example of Figure 5(d). As described above, when the contact surface has a tapered shape in the longitudinal cross-section (y-z cross-section in the figure), the shape formed by the protruding members 21A, 21B and the connecting member 22 in the cross-section parallel to the sides of the steel sheet piles 10A and 10B (x-z cross-section) changes as the cross-section approaches the sides of the steel sheet piles 10A and 10B, stretching in the longitudinal direction (z direction) of the steel sheet piles 10A and 10B.

Figure 6 shows an example of how to attach the connecting structure according to the first embodiment of the present invention to a steel sheet pile wall. In the example shown in Figure 6(a), the connecting structure 20 is attached to the outer sides of the web 12 and arm 14 of the steel sheet pile 10, which is a hat-shaped steel sheet pile. Here, the outer side of the steel sheet pile 10 is the side that is further away from the neutral axis in the wall thickness direction (y-direction in the figure). By attaching the connecting structure 20 to the outer sides of the web 12 and arm 14 of the steel sheet pile wall, the load can be borne more effectively when a bending moment acts on the steel sheet pile wall.

In the example shown in Figure 6(b), the connecting structure 20 is attached to both sides of the steel sheet pile 10 on both sides of the web 12 and arm 14. As described above, by attaching the connecting structure 20 to the web 12 and arm 14, which are farther from the neutral axis in the wall thickness direction of the steel sheet pile wall, the load can be borne more effectively when a bending moment acts on the steel sheet pile 10. The connecting structure 20 needs to be designed so that the cross-section in the longitudinal direction (z direction in the figure) of the steel sheet pile 10 satisfies the required tensile strength. However, by attaching the connecting structure 20 to both sides of the steel sheet pile 10, the total cross-section can be increased while reducing the overhang of each connecting structure 20 from the steel sheet pile 10.

In the example shown in Figure 6(c), the connecting structure 20 is attached to both sides of the steel sheet pile 10 not only on both sides of the web 12 and arm 14, but also on both sides of the flange 13. While the connecting structure 20 attached to the flange bears less load when a bending moment acts on the steel sheet pile wall compared to the web 12 and arm 14, it has the advantage of distributing the load across the entire cross-section of the steel sheet pile 10 when, for example, a construction load (axial force) is applied, thereby suppressing localized yielding of the steel sheet pile 10.

As mentioned above, the connecting structure 20 needs to be designed to meet the required tensile strength so that the steel sheet pile 10 can exhibit the required bending stiffness and bending strength. However, the bending stiffness and bending strength required for the steel sheet pile 10 are not necessarily equivalent to those determined by the cross-sectional shape and steel material specifications of the steel sheet pile 10. For example, if the steel sheet pile wall is a temporary structure, the bending strength required for the steel sheet pile 10 may be about two-thirds of the bending strength determined by the cross-sectional shape and steel material specifications of the steel sheet pile 10. Therefore, in a cross-section like the one shown in Figure 6, for example, the total cross-sectional area of the connecting structure 20 (the smallest cross-sectional portion of the connecting member 22) does not need to be equivalent to the cross-sectional area of the steel sheet pile 10.

Figure 7 shows an example of a detachment prevention structure in a connecting structure according to the first embodiment of the present invention. In the example shown in Figure 7(a), a lid member 23, which has been previously joined to the connecting member 22, is bolted to the protruding members 21A and 21B, respectively. Figure 7(a) shows a bolt hole 231 formed in the lid member 23. Bolt holes are also formed in each of the protruding members 21A and 21B at positions corresponding to the bolt hole 231, and fixing bolts (not shown) are inserted through these bolt holes. In the examples shown in Figures 7(b) and 7(c), fixing bolts 24A and 24B are inserted through bolt holes 212A, 212B, and 222 formed in the protruding members 21A and 21B and the connecting member 22, respectively. To prevent a decrease in watertightness due to drilling and deformation due to cutting, it is desirable that the steel sheet piles 10A and 10B are not processed when attaching the fixing bolts. For this reason, in the examples of Figures 7(b) and 7(c), the fixing bolts 24A and 24B are positioned in a plane parallel to the sides of the steel sheet piles 10A and 10B (the x-z plane in the figures). Even in the example of Figure 7(a), it is desirable that the bolt holes formed in the protruding members 21A and 21B do not penetrate the protruding members 21A and 21B and do not reach the steel sheet piles 10A and 10B.

In the first embodiment of the present invention described above, the connecting member 22 has a shape that surrounds the protruding members 21A and 21B in a cross-section parallel to the sides of the steel sheet piles 10A and 10B (the x-z cross-section in the figure). This reduces the height to which the members of the connecting structure 20 protrude from the surfaces of the steel sheet piles 10A and 10B. Furthermore, by transmitting force between the protruding members 21A and 21B and the connecting member 22 through a pair of contact surfaces on each side of the steel sheet piles 10A and 10B—namely, between contact surfaces 211A and 221A and between contact surfaces 211B and 221B—force can be transmitted stably without concentration on specific parts of the dispersed contact surfaces.

(Second embodiment)
Figure 8 is a perspective view showing a part of a steel sheet pile wall including a connecting structure according to a second embodiment of the present invention. Figure 8 shows a part of the steel sheet piles 10A and 10B and a connecting structure 30 that connects the steel sheet piles 10A and 10B in the longitudinal direction (z direction in the figure). The configuration of the steel sheet piles 10A and 10B and the steel sheet pile wall is the same as in the first embodiment, so it is not shown or described. The connecting structure 30 is attached to at least one side of the web, flange, or arm of the steel sheet piles 10A and 10B. In this embodiment, the connecting structure 30 includes a protruding member 31A (first protruding member) that protrudes from the side of the steel sheet pile 10A at the longitudinal end of the steel sheet pile 10A, a protruding member 31B (second protruding member) that protrudes from the side of the steel sheet pile 10B at the longitudinal end of the steel sheet pile 10B, and a connecting member 32 that fits onto the protruding members 31A and 31B. The protruding members 31A, 31B and the connecting member 32 are steel plate-shaped members having the shapes described below. In this embodiment, the connecting member 32 has a C-shaped open form in a cross section parallel to the sides of the steel sheet piles 10A, 10B (x-z cross section in the figure) and does not surround one of the side end faces of the protruding members 31A, 31B.

Figures 9 and 10 show the formation process of the connecting structure shown in Figure 8, with Figure 9 being a view along the line VIII-VIII in Figure 8. As shown, the connecting structure 30 is formed, for example, by first joining protruding members 31A and 31B to steel sheet piles 10A and 10B by welding or the like, butting the end faces of the steel sheet piles 10A and 10B in the longitudinal direction, and then fitting the connecting member 32 onto the protruding members 31A and 31B from a direction perpendicular to the longitudinal direction of the steel sheet piles 10A and 10B and parallel to the side surfaces of the steel sheet piles 10A and 10B (in the case of a web or arm, the wall width direction of the steel sheet pile wall (the x direction in the figure)). The protruding member 31A has a contact surface 311A (first contact surface) directed toward the longitudinal center of the steel sheet pile 10A, and the protruding member 31B has a contact surface 311B directed toward the longitudinal center of the steel sheet pile 10B. On the other hand, the connecting member 32 has contact surfaces 321A (third contact surface) and 321B (fourth contact surface) facing each other inside the C-shaped opening that partially encloses the protruding members 31A and 31B as described above. The contact surface 321A of the connecting member 32 contacts the contact surface 311A of the protruding member 31A, and the contact surface 321B contacts the contact surface 311B of the protruding member 31B. This transmits bearing pressure between the respective contact surfaces, allowing the connecting structure 30 to function as a connecting part capable of transmitting tensile force between the steel sheet piles 10A and 10B. Note that, as with the first embodiment described above, compressive force does not necessarily have to be transmitted by the connecting structure 30.

In the illustrated example, the contact surfaces 311A and 311B of the protruding members 31A and 31B have a taper formed in a cross-section parallel to the sides of the steel sheet piles 10A and 10B (the x-z cross-section in the figure), becoming narrower as they move away from the side end faces 313A and 313B that are not enclosed by the connecting member 32. That is, in the above cross-section, the protruding members 31A and 31B, including the contact surfaces 211A and 211B, are trapezoidal as a whole, with the side end faces 313A and 313B as the base. The contact surfaces 321A and 321B of the connecting member 32 have a shape corresponding to the contact surfaces 311A and 311B in order to contact the contact surfaces of the protruding members 31A and 31B. That is, in the above cross-section, the space inside the C-shaped opening of the connecting member 32 expands toward the protruding members 31A and 31B.

Furthermore, in the example shown in Figure 8, the contact surfaces 311A and 311B of the protruding members 31A and 31B have a taper that narrows as it approaches the steel sheet piles 10A and 10B in a cross-section (y-z cross-section in the figure) that includes the longitudinal direction of the steel sheet piles 10A and 10B and is perpendicular to the side surfaces of the steel sheet piles 10A and 10B. In other words, in the above cross-section, the protruding members 31A and 31B, including the contact surfaces 311A and 311B, are trapezoidal as a whole, with the base on the side opposite to the steel sheet piles 10A and 10B. The contact surfaces 321A and 321B of the connecting member 32 have a shape corresponding to the contact surfaces 311A and 311B in order to contact the contact surfaces of the protruding members 31A and 31B. In other words, in the above cross-section, the space sandwiched by the contact surfaces 321A and 321B of the connecting member 32 narrows toward the steel sheet piles 10A and 10B. This prevents the connecting member from detaching from the side of the steel sheet pile (in the y-direction).

As described above, by tapering the contact surfaces of the protruding members 31A, 31B and the connecting member 32, dimensional errors in the protruding members 31A, 31B and the connecting member 32, as well as errors in the mounting position of the protruding members 31A, 31B to the steel sheet piles 10A, 10B, can be absorbed, allowing the contact surfaces 311A, 311B of the protruding members 31A, 311B and the contact surfaces 321A, 321B of the connecting member 32 to come into contact without any gaps. Furthermore, in this embodiment, the connecting member 32 has a C-shaped opening and is fitted onto the protruding members 31A, 31B from the side. Therefore, the tapering creates a dovetail-like shape in the longitudinal cross-section of the protruding members 31A, 31B, and together with the fixing bolt described next, this prevents the connecting member 32 from detaching.

As shown in Figure 10, with the connecting member 32 fitted onto the protruding members 31A and 31B, the fixing bolts 34A and 34B are inserted through the bolt holes 312A, 312B, and 322 formed in the protruding members 31A and 31B and the connecting member 32, respectively. This prevents the connecting member 32 from coming loose and maintains a state where bearing pressure is transmitted between the contact surfaces of the protruding members 31A and 31B and the connecting member 32. In the illustrated example, the fixing bolts 34A and 34B are inserted horizontally (in the x-direction in the figure), but as in the example described with reference to the first embodiment, the fixing bolts may also be inserted vertically (in the z-direction) or diagonally. As in the first embodiment, it is desirable that the machining of bolt holes and other features does not extend to the steel sheet piles 10A and 10B.

In the second embodiment of the present invention described above, similar to the first embodiment, the connecting member 32 has a shape that surrounds the protruding members 31A and 31B in a cross section parallel to the sides of the steel sheet piles 10A and 10B (x-z cross section in the figure), thereby reducing the height to which the members of the connecting structure 30 protrude from the surface of the steel sheet piles 10A and 10B. Furthermore, by transmitting force between the protruding members 31A and 31B and the connecting member 32 through a pair of contact surfaces on each side of the steel sheet piles 10A and 10B, namely between contact surfaces 311A and 321A and between contact surfaces 311B and 321B, force is not concentrated in a specific part of the dispersed contact surfaces, and force can be transmitted stably. In comparison with the first embodiment, in this embodiment, since the connecting member 32 is fitted onto the protruding members 31A and 31B from the side, it is easy to prevent rattling and detachment of the connecting member 32 by the tapered shape described above. On the other hand, in this embodiment, the connecting member 32 has an open shape that opens on one side end face of the protruding members 31A and 31B, whereas in the first embodiment, the connecting member has a closed shape that surrounds the entire circumference including both side end faces of the protruding members. Therefore, the first embodiment is advantageous in that it is easier to secure a cross-section that satisfies the required tensile strength.

Although preferred embodiments of the present invention have been described in detail above with reference to the attached drawings, the present invention is not limited to these examples. It is clear to any person with ordinary skill in the art to which the present invention pertains that various modifications or variations can be conceived within the scope of the technical idea described in the claims, and these are also understood to naturally fall within the technical scope of the present invention.

10, 10A, 10B…Steel sheet pile, 11…Joint, 12…Web, 13…Flange, 14…Arm, 20…Connecting structure, 21A, 21B…Protruding member, 211A, 211B…Contact surface, 212A, 212B…Bolt hole, 22…Connecting member, 221A, 221B…Contact surface, 222…Bolt hole, 23…Cover member, 231…Bolt hole, 24A, 24B…Fixing bolt, 30…Connecting structure, 31A, 31B…Protruding member, 311A, 311B…Contact surface, 312A, 312B…Bolt hole, 313A, 313B…Side end face, 32…Connecting member, 321A, 321B…Contact surface, 322…Bolt hole, 34A, 34B…Fixing bolt.

Claims (13)

A connecting structure for connecting first and second steel sheet piles to each other at their longitudinal ends,
A first protruding member having a first contact surface that protrudes from the side surface of the first steel sheet pile at the longitudinal end of the first steel sheet pile and is directed toward the longitudinal center of the first steel sheet pile,
A second protruding member having a second contact surface that protrudes from the side surface of the second steel sheet pile at the longitudinal end of the second steel sheet pile and is directed toward the longitudinal center of the second steel sheet pile,
The connecting member has a third contact surface that contacts the first contact surface and a fourth contact surface that contacts the second contact surface, and has a shape that at least partially surrounds both the first and second protruding members in a cross-section parallel to the sides of the first and second steel sheet piles ,
The first protruding member and the second protruding member are arranged in the space sandwiched between the third contact surface and the fourth contact surface.
The portion of the connecting member that connects the portion where the third contact surface is formed and the portion where the fourth contact surface is formed is a connecting structure that is in contact with the side surfaces of the first and second steel sheet piles . The connecting member has a closed shape that surrounds the entire circumference of the first and second protruding members in a cross-section parallel to the sides of the first and second steel sheet piles, according to claim 1. The connecting structure according to claim 2, wherein the first and second contact surfaces have a taper formed in a cross-section that includes the longitudinal direction of the first and second steel sheet piles and is perpendicular to the side surfaces of the first and second steel sheet piles, becoming narrower as they move away from the first and second steel sheet piles. The connecting structure according to claim 2 or 3, wherein the overall shape formed by the first and second protruding members in a cross-section parallel to the sides of the first and second steel sheet piles is rectangular, hexagonal, hourglass-shaped, or elliptical. The connecting structure according to any one of claims 2 to 4, further comprising the connecting member or a cover member joined to the connecting member and fixing bolts inserted through the first and second protruding members, wherein the bolt holes formed in the first and second protruding members do not penetrate the first and second protruding members and do not reach the first and second steel sheet piles . A method for connecting steel sheet piles using the connecting structure described in any one of claims 2 to 5,
A step of joining the first protruding member to the side surface of the first steel sheet pile,
The process of joining the second protruding member to the side surface of the second steel sheet pile,
The process of butting the first steel sheet pile and the second steel sheet pile at their longitudinal end faces,
A method for connecting steel sheet piles, comprising the steps of: fitting the connecting member onto the first and second protruding members from the side opposite to the side of the first and second steel sheet piles; bringing the third contact surface into contact with the first contact surface; and bringing the fourth contact surface into contact with the second contact surface. The connecting member has an open shape in a cross-section parallel to the sides of the first and second steel sheet piles, and does not enclose one of the side end faces of the first and second protruding members, as described in claim 1. The connecting structure according to claim 7, wherein the first and second contact surfaces have a taper formed in a cross-section perpendicular to the sides of the first and second steel sheet piles, including the longitudinal direction of the first and second steel sheet piles, becoming narrower as they approach the first and second steel sheet piles. The connecting structure according to claim 7 or 8, wherein the first and second contact surfaces have a taper formed in a cross-section parallel to the sides of the first and second steel sheet piles, becoming narrower as they move away from the side end surface not enclosed by the connecting member. The connecting structure according to any one of claims 7 to 9, further comprising fixing bolts inserted through the first and second protruding members and the connecting member , wherein the fixing bolts are arranged in a plane parallel to the sides of the first and second steel sheet piles . A method for connecting steel sheet piles using the connecting structure described in any one of claims 7 to 10,
A step of joining the first protruding member to the side surface of the first steel sheet pile,
The process of joining the second protruding member to the side surface of the second steel sheet pile,
The process of butting the first steel sheet pile and the second steel sheet pile at their longitudinal end faces,
A method for connecting steel sheet piles, comprising the steps of: fitting the connecting member onto the first and second protruding members from a direction parallel to the sides of the first and second steel sheet piles; bringing the third contact surface into contact with the first contact surface; and bringing the fourth contact surface into contact with the second contact surface. A steel sheet pile structure comprising the connecting structure described in any one of claims 1 to 5 or 7 to 10,
The first and second steel sheet piles are hat-shaped steel sheet piles,
A steel sheet pile structure in which the connecting structure is attached to at least one side of the web, arm, or flange of the hat-shaped steel sheet pile. The steel sheet pile structure according to claim 12, wherein the connecting structure is attached to both sides of the first and second steel sheet piles by the web and the arm.