Hat-shaped steel sheet pile and method for manufacturing steel sheet pile wall

Abstract

To provide a hat-shaped steel sheet pile and a method for manufacturing a steel sheet pile wall which can reduce inclination deformation generated in a hat-shaped steel sheet pile during installation.SOLUTION: A hat-shaped steel sheet pile includes a web extending in a width direction, a pair of flanges extending from both ends in a width direction of the web, a pair of arms extending toward both sides in the width direction of the pair of flanges, and a pair of fitting joints formed on the ends of the pair of arms. An effective width W is 105 cm or more, a cross-sectional secondary moment Iy around a strong axis extending in a cross-sectional height direction is 191,000 cm4 or more, and a ratio Iy / H of a cross-sectional height H (cm) to the cross-sectional secondary moment Iy (cm4) around the strong axis is 5,210 cm3 or more.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a hat-shaped steel sheet pile and a method for manufacturing a steel sheet pile wall. [Background technology]

[0002] Hat-shaped steel sheet piles are widely used in civil engineering and construction projects to construct walls for earth retaining and watertightness. Various technologies for improving the workability and cross-sectional performance of hat-shaped steel sheet piles have been proposed. For example, Patent Document 1 describes a technology for setting the flange angle in the cross section of a hat-shaped steel sheet pile, i.e., the angle between the flange and the web and arm, so as to minimize penetration resistance during driving. Patent Document 2 also describes a technology for determining a cross-sectional shape that optimizes the economy, workability, and soundness of a hat-shaped steel sheet pile, focusing on penetration resistance. Patent Document 3 describes a method for setting the shape of a hat-shaped steel sheet pile that has excellent cross-sectional performance, such as a moment of inertia. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3488233 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-158910 [Patent Document 3] Japanese Patent Application Laid-Open No. 2008-69631 Summary of the Invention [Problem to be solved by the invention]

[0004] Here, the moment of inertia of the hat-type steel sheet piles mentioned in the above Patent Documents 1 to 3 is the moment of inertia about the weak axis. This moment of inertia about the weak axis represents the rigidity of the steel sheet pile wall formed by the hat-type steel sheet pile after driving when it resists earth pressure and water pressure underground, and is therefore an important index of the performance of the hat-type steel sheet pile.

[0005] However, as will be described later, according to the findings of the present inventors, the moment of inertia around the weak axis is not necessarily an appropriate design index for reducing the tilt deformation that occurs in a hat-shaped steel sheet pile during driving. In a hat-shaped steel sheet pile during driving, joint friction that occurs when the joint fits with the steel sheet pile driven previously acts as resistance. Unlike penetration resistance, the resistance due to joint friction acts unevenly on the cross section of the hat-shaped steel sheet pile, so the hat-shaped steel sheet pile may not be driven evenly in the depth direction and may tilt.

[0006] This inclination accumulates as the hat-shaped steel sheet piles are sequentially driven in the wall width direction, and this can cause the steel sheet piles to remain in place only halfway due to the increased inclination, or can lead to a situation where the shape of the steel sheet pile wall deviates significantly from the design. According to the findings of the inventors, the moment of inertia about the strong axis is more appropriate as a design index for reducing inclination deformation than the general moment of inertia about the weak axis.

[0007] Therefore, an object of the present invention is to provide a new and improved method for manufacturing a hat-shaped steel sheet pile and a steel sheet pile wall, which can reduce the inclined deformation that occurs in the hat-shaped steel sheet pile during installation by appropriately setting the second moment of area around the strong axis. [Means for solving the problem]

[0008] According to an aspect of the present invention, a hat-shaped steel sheet pile has, in a cross section perpendicular to the longitudinal direction, a web extending along a width direction on a first side in a cross-section height direction, a pair of flanges extending from both ends of the web in the width direction to both sides in the width direction and toward a second side in the cross-section height direction, a pair of arms extending from each end of the pair of flanges on the second side in the cross-section height direction along the width direction and toward both sides in the width direction, and a pair of fitting joints formed at each end of the pair of arms opposite to the pair of flanges, and has an effective width W of 105 cm or more and a moment of inertia Iy about a strong axis extending in the cross-section height direction of 191,000 cm4 The cross-sectional height H (cm) and the second moment of area around the strong axis Iy (cm 4 ) and the ratio Iy / H is 5,210 cm 3 That's all.

[0009] The effective width W of the hat-shaped steel sheet pile may be 120 cm or more.

[0010] According to another aspect of the present invention, there is provided a method for manufacturing a steel sheet pile wall using the above-mentioned hat-shaped steel sheet pile. The method for manufacturing a steel sheet pile wall may include a step of driving the hat-shaped steel sheet pile into the ground while fitting only one of the fitting joints of the hat-shaped steel sheet pile into the fitting joint of a steel sheet pile that has been driven previously.

[0011] According to the above configuration, by appropriately setting the moment of inertia around the strong axis, it is possible to reduce the inclined deformation that occurs in the hat-shaped steel sheet pile during installation. As a result, for example, the above-mentioned high-level retention and deviation from the design in the shape of the steel sheet pile wall can be suppressed, and construction quality can be improved. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a cross-sectional view of a hat-shaped steel sheet pile according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram for explaining the fitting center of the hat-shaped steel sheet pile shown in FIG. [Figure 3] FIG. 10 is a diagram for conceptually explaining the inclined deformation that occurs in a hat-shaped steel sheet pile during driving. [Figure 4] 1 is a graph showing bending ratios on the vertical axis and second moment of area about the strong axis on the horizontal axis for examples of the present invention and comparative examples. [Figure 5] 10 is a graph illustrating an example of a criterion for effectively reducing tilt deformation. [Figure 6] 10 is a graph illustrating an example of a criterion for effectively reducing tilt deformation. [Figure 7]FIG. 10 is a diagram for explaining the relationship between the inclination deformation and the cross-sectional height of a hat-shaped steel sheet pile. [Figure 8] 1 is a graph showing bending ratios on the vertical axis and ratios of moment of inertia about the strong axis to cross-sectional heights for examples of the present invention and comparative examples. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this specification and drawings, components having substantially the same functional configurations are designated by the same reference numerals, and redundant description will be omitted.

[0014] Fig. 1 is a cross-sectional view of a hat-shaped steel sheet pile according to one embodiment of the present invention. As shown in Fig. 1, the hat-shaped steel sheet pile 1 includes, in a cross section perpendicular to the longitudinal direction (z direction in the figure), a web 2 extending along the width direction (x direction in the figure) on a first side in the cross-sectional height direction (the rear side in the y direction in the figure), flanges 3A and 3B extending from both ends of the web 2 in the width direction to both sides in the width direction and toward a second side in the cross-sectional height direction (the front side in the y direction in the figure) and forming a flange angle θ (acute angle side) with the width direction, arms 4A and 4B extending along the width direction from the ends of the flanges 3A and 3B on the second sides in the cross-sectional height direction and toward both sides in the width direction, and fitting joints 5A and 5B formed at the ends of the arms 4A and 4B opposite to the flanges 3A and 3B.

[0015] 1 shows the dimensions of each part of the hat-shaped steel sheet pile 1, specifically, the length Bw and thickness tw of the web 2, and the length Ba of the arms 4A and 4B. Here, the length Bw is the distance between two intersections formed between the thickness center line of the web 2 and the thickness center lines of the flanges 3A and 3B. Also, the length Ba is the distance between the intersection formed between the thickness center line of the arm 4A and the thickness center line of the flange 3A and the fitting center E of the fitting joint 5A. ASince the cross-sectional shape of the hat-shaped steel sheet pile 1 is symmetrical about the neutral axis in the width direction (y-axis in the drawing), the arm 4B also has the length Ba, just like the arm 4A.

[0016] 1 further shows the effective width W, cross-sectional height H, weak axis Ax, and strong axis Ay of the hat-shaped steel sheet pile 1. Here, the effective width W is the distance between the fitting centers E of the fitting joints 5A and 5B. A ,E B The cross-sectional height H is the height of the cross section of the hat-shaped steel sheet pile 1, including the plate thickness of the web 2 and the arms 4A, 4B but not including the overhang of the fitting joints 5A, 5B. The weak axis Ax is the neutral axis extending in the width direction of the hat-shaped steel sheet pile 1, and the strong axis Ay is the neutral axis extending in the cross-sectional height direction of the hat-shaped steel sheet pile 1. As will be described later, in the hat-shaped steel sheet pile 1 according to this embodiment, the effective width W is 105 cm or more, and the moment of inertia Iy about the strong axis Ay is 191,000 cm 4 That's all.

[0017] When the shape of the hat-shaped steel sheet pile 1 shown in Figure 1 is geometrically valid, the effective width W, web length Bw, cross-sectional height H, and flange angle θ satisfy the relationship W-Bw-2H / tanθ>0.

[0018] 2 is a diagram for explaining the fitting center of the hat-shaped steel sheet pile shown in FIG. 1. As shown in the figure, a fitting joint 5A of a hat-shaped steel sheet pile 1 is fitted with a fitting joint 5B of another hat-shaped steel sheet pile 1 that is driven adjacently. The fitting center E of the fitting joint 5A A can be defined as a point on the design plate thickness center line of the arm 4A and the arm 4B, which is located midway between the end position of the arm 4A where the fitted joint 5A is formed and the end position of the arm 4B where the virtual fitted joint 5B is formed, when the arm 4B and the fitted joint 5B of another hat-shaped steel sheet pile 1 are virtually arranged. B can be defined similarly.

[0019] Fig. 3 is a diagram for conceptually explaining the inclination deformation that occurs in a hat-shaped steel sheet pile during driving. As shown in Fig. 3, the hat-shaped steel sheet pile 1 is driven into the ground while fitting the fitting joint 5A into the fitting joint 5B of the hat-shaped steel sheet pile 1P that was driven in advance. At this time, the penetration force F P acts near the centroid C of the cross section of the hat-shaped steel sheet pile 1, while the joint friction force F generated by the fitting joint 5A of the hat-shaped steel sheet pile 1 fitting into the fitting joint 5B of the hat-shaped steel sheet pile 1P F acts on the width direction end of the hat-shaped steel sheet pile 1. In this way, the couple F generated by the action of two forces acting at different points of action is C Due to the rotational action of the hat-shaped steel sheet pile 1, the hat-shaped steel sheet pile 1 deforms so as to tilt toward the hat-shaped steel sheet pile 1P that was driven in advance, and the fitting joint 5A deforms toward the lower end, increasing the amount of overlap with the hat-shaped steel sheet pile 1P in the wall width direction. The amount of tilt accumulates with the number of driven piles (if the hat-shaped steel sheet pile 1P that was driven in advance is tilted, the hat-shaped steel sheet pile 1 that is driven next will be even more tilted), so some method is needed to reduce the tilt deformation of the hat-shaped steel sheet pile 1 during driving.

[0020] (Study on second moment of area around the strong axis) The force couple F described above with reference to FIG. C What resists deformation due to the rotational action of the hat-shaped steel sheet pile 1 is the rigidity of the hat-shaped steel sheet pile 1 in the direction of deformation, specifically the moment of inertia Iy around the strong axis (y-axis in the figure) of the hat-shaped steel sheet pile 1. The moment of inertia Iy increases if the dimensions of the hat-shaped steel sheet pile 1, such as the effective width W, cross-sectional height H, and plate thickness t, are increased, but the inventors have focused on the effective width W among these dimensions. The moment of inertia Iy around the strong axis of the hat-shaped steel sheet pile 1 is proportional to the cube of the effective width W, which is the dimension in the direction perpendicular to the strong axis. On the other hand, if the effective width W is increased, the couple F C However, the arm length of the moment acting on the hat-shaped steel sheet pile 1 increases only in proportion to the first power of the effective width W (W / 2). Therefore, the increase in the stiffness of the hat-shaped steel sheet pile 1 due to the expansion of the effective width W, that is, the increase in the moment of inertia Iy, is due to the increase in the couple F CThis increase is significantly larger than the increase in moment acting due to the load, and is effective in reducing the tilting deformation of the hat-type steel sheet pile 1. As will be explained below with reference to Table 1, by increasing the effective width W of the hat-type steel sheet pile 1 to 105 cm or more and further increasing the second moment of area Iy to a predetermined range or more, the tilting deformation can be effectively reduced. Furthermore, since the number of hat-type steel sheet piles required is reduced as the effective width W increases for the same steel sheet pile wall width, increasing the effective width W is also advantageous from the viewpoint of construction economy.

[0021] Table 1 shows the cross-sectional specifications of the conventional hat-shaped steel sheet piles (Comparative Examples 1 to 3) and the hat-shaped steel sheet piles according to the embodiments of the present invention (Examples 1 to 6). In Table 1, W is the effective width (cm), H is the cross-sectional height (cm), tw is the web thickness (cm), Bw is the web length (cm), Ba is the arm length (cm), and Ix is the moment of inertia (cm) around the weak axis (x-axis shown in Figure 4). 4 / m; per 1 m of wall width of steel sheet pile wall), Iy is the moment of inertia about the strong axis (y-axis shown in Figure 4) (cm 4 (per hat-shaped steel sheet pile). Ix and Iy are calculated taking into consideration the curved shapes between the web and flange, and between the flange and arm, and the shape of the fitting joint. In all of Examples 1 to 6, the effective width W of the hat-shaped steel sheet pile 1 was set to 105 cm or more.

[0022] Here, the bending ratio r in Table 1 B is calculated by the following formula (1) as the ratio of the amount of inclination deformation between each example and a conventional hat-shaped steel sheet pile having the same moment of inertia Ix. In formula (1), a is a coefficient due to the boundary condition, M and M' are the couple F in each example and comparative example. C moment generated by the hat-shaped steel sheet pile, L is the length of the hat-shaped steel sheet pile, E is the Young's modulus of the hat-shaped steel sheet pile, R is the joint resistance, specifically the joint friction force F FThe length L and Young's modulus E are common to the examples and comparative examples. As will be described later, the joint resistance R varies depending on the cross-sectional height H of the hat-shaped steel sheet pile. However, in the example of Table 1, the cross-sectional height H is common between the conventional hat-shaped steel sheet pile and the hat-shaped steel sheet piles of each example, which have the same moment of inertia Ix. Therefore, in formula (1), the joint resistance R is common between the examples and comparative examples. In this case, the bending ratio r B can be expressed by the effective widths W, W' and the second moments of area Iy, Iy' around the strong axis of each of the hat-shaped steel sheet piles of the example and the comparative example.

[0023]

number

[0024] [Table 1]

[0025] FIG. 4 shows the bending ratio r B The vertical axis is the moment of inertia of area around the strong axis Iy (cm 4 4, the horizontal axis shows the moment of inertia Iy about the strong axis in Examples 1 to 6, and the bending ratio r B Specifically, the second moment of area Iy is the smallest in Example 5 (Iy = 191,625 cm 4 ) and the bending ratio r B In Example 5, the effective width W is also the smallest (W = 105 cm). From this result, it is considered that the effective width W of the hat-shaped steel sheet pile should be 105 cm or more and the moment of inertia Iy around the strong axis per hat-shaped steel sheet pile should be 191,000 cm 4 By doing so, it can be said that tilt deformation can be effectively reduced.

[0026] 5 and 6 show the bending ratio r BThis graph explains why the standard for effectively reducing tilt deformation is set at q = 0.83. Figure 5 shows the tolerance q of the bending (width direction deformation) of U-shaped steel sheet piles specified in JIS A5523 "Hot-rolled steel sheet piles for welding." u Similarly, the bending tolerance q of the hat-shaped steel sheet pile HAT 6 is a graph showing the ratio q of the tolerances of the U-shaped steel sheet piles and the hat-shaped steel sheet piles shown in FIG. u / q HAT As shown in Fig. 6, when the length L of the steel sheet pile is 10 m or less, the ratio q u / q HAT becomes constant at about 0.83. In other words, when the steel sheet pile length L is in the range of 10 m or less, the allowable width direction deformation of a U-shaped steel sheet pile is 0.83 times that of a hat-shaped steel sheet pile. Since a U-shaped steel sheet pile does not have an arm portion, width direction deformation progresses more easily than a hat-shaped steel sheet pile, and therefore the allowable bending during manufacturing or construction is specified to be smaller than that of a hat-shaped steel sheet pile. Conversely, if a hat-shaped steel sheet pile only generates bending equivalent to that of a U-shaped steel sheet pile, it will also meet the stricter bending standard for a U-shaped steel sheet pile. Therefore, in the above example, the bending ratio r B is set to 0.83 as one of the criteria for effectively reducing tilt deformation.

[0027] As shown in Figs. 5 and 6, when the length L of the steel sheet pile exceeds 10 m, the ratio q u / q HAT In this range, from the viewpoint of satisfying the bending criteria of the U-shaped steel sheet pile, the bending ratio r B It can be said that the inclined deformation is effectively reduced even when the length L of the steel sheet pile exceeds 20 m. u As a result of the plateauing of u / q HAT Taking this into consideration, the ratio q u / q HAT The bending ratio r according to the value of BThe moment of inertia Iy may be determined so that the following is realized. Specifically, for example, when the length L of the steel sheet pile is 25 m (q u / q HAT =0.74) has a bending ratio r B The moment of inertia Iy may be determined so that the difference between the shapes of U-shaped steel sheet piles and hat-shaped steel sheet piles (even if the length L exceeds 20 m, the allowable difference q HAT Even in the range where the length L exceeds 20 m, the bending ratio r B The second moment of area Iy may be determined so that is 0.83 or less.

[0028] As shown in Figures 5 and 6, the bending ratio r B Considering this point, it is more preferable that the effective width W of the hat-type steel sheet pile is, for example, 120 cm or more. In most cases, the length of the hat-type steel sheet pile is 25 m or less, and from Figure 6, the bending ratio r B If the bending ratio r is 0.7 or less, the tilt deformation can be effectively reduced. According to the study by the inventors, when the effective width W is set to 120 cm or more, the bending ratio r can be reduced by appropriately setting other dimensions such as the plate thickness of each part. B It becomes easy to reduce the value to 0.7 or less.

[0029] (Considerations regarding cross-sectional height) 7 is a diagram for explaining the relationship between the inclination deformation and the cross-sectional height of a hat-shaped steel sheet pile. As shown in Fig. 7, the hat-shaped steel sheet pile 1 undergoes internal pressure P due to blockage resistance caused by soil S that has flowed into the internal space surrounded by the web 2 and flanges 3A and 3B. I The internal pressure P I acts to push the hat-shaped steel sheet pile 1 outward in the width direction (x direction in the figure), so the internal pressure P I When the force F increases, the fitting joint 5A is pressed against the fitting joint 5B of the hat-shaped steel sheet pile 1P that was installed earlier, and the joint friction force F acting due to the contact between the fitting joint 5A and the fitting joint 5B increases. FAs described in, for example, Japanese Patent No. 3488233, the blockage resistance caused by the soil S flowing into the internal space of the hat-shaped steel sheet pile 1 is proportional to the cross-sectional height H of the hat-shaped steel sheet pile 1, so the internal pressure P due to the blockage resistance caused by the soil S increases. I and joint friction force F F is also proportional to the cross-sectional height H. Therefore, it is reasonable to express the condition for reducing the inclined deformation by the relationship between the cross-sectional height H of the hat-shaped steel sheet pile 1 and the second moment of area Iy around the strong axis.

[0030] Table 2 shows the cross-sectional specifications of the conventional hat-shaped steel sheet piles (Comparative Examples 1 to 3) and the hat-shaped steel sheet piles according to the embodiments of the present invention (Examples 7 to 15). In addition to the same items as in Table 1, Table 2 also shows the ratio Iy / H (cm 3 ) is shown. In Examples 7 to 15, the effective width W of the hat-shaped steel sheet pile 1 is 105 cm or more.

[0031] Here, the bending ratio r in Table 2 B is the ratio of the amount of inclination deformation between each example and a conventional hat-shaped steel sheet pile having the same moment of inertia Ix as in Table 1, but the following formula (3) is used for the calculation. In Examples 7 to 15, the cross-sectional height H is changed from that of the conventional hat-shaped steel sheet pile, so in formula (3), the joint resistances R and R' of the examples and the comparative example are treated as different values. Here, as mentioned above, the joint friction force F F Since is proportional to the cross-sectional height H of the hat-shaped steel sheet pile, the relationship between the joint resistance R, R' and the cross-sectional height H, H' can be expressed using the coefficient b according to the soil conditions and construction method as shown in equation (2). In this case, the bending ratio r B can be expressed by the effective widths W, W', the second moments of area Iy, Iy' around the strong axis, and the cross-sectional heights H, H' of the hat-shaped steel sheet piles of the example and the comparative example.

[0032]

number

[0033] [Table 2]

[0034] FIG. 8 shows the bending ratio r B The vertical axis is the ratio of the moment of inertia Iy around the strong axis to the cross-sectional height H, Iy / H (cm 3 8 is a graph showing the Iy / H ratio on the horizontal axis. Referring to the graph of FIG. 8, in Examples 7 to 15, Iy / H is larger than in Comparative Examples 1 to 3, and the bending ratio r B Specifically, Example 12 (Iy / H=5,213 cm) has the smallest Iy / H. 3 ) and the bending ratio r B In Example 12, the effective width W is also the smallest (W = 105 cm). From this result, it is recommended to set the effective width W of the hat-shaped steel sheet pile to 105 cm or more and set the ratio Iy / H of the moment of inertia Iy around the strong axis to the cross-sectional height H to 5,210 cm. 3 By setting the above, it can be said that the inclined deformation can be effectively reduced. In addition, Examples 7 to 15 are those in which the conditions referred to in Table 1 above, that is, the effective width W of the hat-shaped steel sheet pile is 105 cm or more and the moment of inertia Iy around the strong axis per hat-shaped steel sheet pile is 191,000 cm 4 The above condition is also met.

[0035] Also, as shown in Table 2, the bending ratio r B is affected by the cross-sectional height H, but the cross-sectional height H is subject to various constraints depending on the application of the hat-shaped steel sheet pile. Therefore, it is necessary to set the cross-sectional height H somewhat freely according to the constraints while maintaining the bending ratio r B In order to stably reduce the effective width W of the hat-shaped steel sheet pile, it is more preferable to make it larger, specifically, for example, 120 cm or more.

[0036] According to the embodiment of the present invention described above, a hat-shaped steel sheet pile having a cross-sectional shape that effectively reduces tilt deformation during driving is provided. Such a hat-shaped steel sheet pile is particularly advantageous in a method for manufacturing a steel sheet pile wall, for example, including a step of driving a hat-shaped steel sheet pile into the ground while fitting only one of a pair of fitting joints of the hat-shaped steel sheet pile into the fitting joint of a steel sheet pile previously driven. In such a method for manufacturing a steel sheet pile wall, the position at which the construction machine supports the steel sheet pile and applies a vertical vibration load is eccentric to the position at which one joint of the hat-shaped steel sheet pile fits into the joint of the steel sheet pile previously driven. Therefore, a moment that causes tilt deformation in the hat-shaped steel sheet pile is likely to occur. However, by applying the embodiment of the present invention, tilt deformation can be effectively suppressed.

[0037] By suppressing the tilt deformation of the hat-shaped steel sheet pile, the driving energy from the construction machine is efficiently transmitted to the hat-shaped steel sheet pile, maintaining a high penetration speed of the hat-shaped steel sheet pile into the ground, enabling economical construction and reducing noise and vibration associated with construction. As the construction machine becomes larger due to the larger cross-section of the hat-shaped steel sheet pile, noise and vibration may also increase, but by suppressing the tilt deformation of the hat-shaped steel sheet pile, construction with reduced noise and vibration is possible.

[0038] In addition, by suppressing the inclined deformation of the hat-shaped steel sheet pile, the fitting resistance with the joint of the steel sheet pile that was cast earlier can be reduced, thereby reducing the resistance of the entire hat-shaped steel sheet pile when cast and preventing scraping and welding at the contact surface of the joint.

[0039] Although the preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that a person skilled in the art to which the present invention pertains can conceive of various modifications and alterations within the scope of the technical ideas set forth in the claims, and it is understood that these also naturally fall within the technical scope of the present invention. [Explanation of symbols]

[0040] 1...Hat-shaped steel sheet pile, 1P...Hat-shaped steel sheet pile, 2...Web, 3A, 3B...Flange, 4A, 4B...Arm, 5A, 5B...Fitting joint, E A ,E B ...Mating center.

Claims

1. A hat-shaped steel sheet pile, In a cross section perpendicular to the longitudinal direction, the cross section comprises: a web extending along a width direction on a first side in a cross-sectional height direction; a pair of flanges extending from both ends of the web in the width direction to both sides in the width direction and toward a second side in the cross-sectional height direction; a pair of arms extending from ends of the pair of flanges along the width direction and toward both sides in the width direction on the second side in the cross-sectional height direction; and a pair of fitting joints formed at ends of the pair of arms opposite the pair of flanges, a moment of inertia Ix about a weak axis extending in the width direction is 9,899 cm 4 / m or more and 11,157 cm 4 / m or less per 1 m of wall width of the steel sheet pile wall constituted by the hat-shaped steel sheet pile; The effective width W is 105 cm or more, and the second moment of area Iy about the strong axis extending in the cross-sectional height direction is 191,000 cm ４ That's all, Section height H (cm) and the second moment of area Iy (cm ４ ) and the ratio Iy / H is 5,210 cm ３ That's all, A hat-shaped steel sheet pile having a length L of 25 m or less and a bending ratio r B calculated by formula (i) of 0.7 or less.

2. A hat-shaped steel sheet pile, In a cross section perpendicular to the longitudinal direction, the cross section comprises: a web extending along a width direction on a first side in a cross-sectional height direction; a pair of flanges extending from both ends of the web in the width direction to both sides in the width direction and toward a second side in the cross-sectional height direction; a pair of arms extending from ends of the pair of flanges along the width direction and toward both sides in the width direction on the second side in the cross-sectional height direction; and a pair of fitting joints formed at ends of the pair of arms opposite the pair of flanges, a moment of inertia Ix about a weak axis extending in the width direction is 24,035 cm 4 / m or more and 26,504 cm 4 / m or less per meter of wall width of the steel sheet pile wall constituted by the hat-shaped steel sheet piles; The effective width W is 105 cm or more, and the second moment of area Iy about the strong axis extending in the cross-sectional height direction is 191,000 cm 4 or more; a ratio Iy / H of a cross-sectional height H (cm) to a second moment of area Iy (cm 4 ) about the strong axis is 5,210 cm 3 or more; A hat-shaped steel sheet pile having a length L of 25 m or less and a bending ratio r B calculated by formula (ii) of 0.7 or less.

3. A hat-shaped steel sheet pile, In a cross section perpendicular to the longitudinal direction, the cross section comprises: a web extending along a width direction on a first side in a cross-sectional height direction; a pair of flanges extending from both ends of the web in the width direction to both sides in the width direction and toward a second side in the cross-sectional height direction; a pair of arms extending from ends of the pair of flanges along the width direction and toward both sides in the width direction on the second side in the cross-sectional height direction; and a pair of fitting joints formed at ends of the pair of arms opposite the pair of flanges, a moment of inertia Ix about a weak axis extending in the width direction is 45,481 cm 4 / m or more and 48,313 cm 4 / m or less per meter of wall width of the steel sheet pile wall constituted by the hat-shaped steel sheet piles; The effective width W is 105 cm or more, and the second moment of area Iy about the strong axis extending in the cross-sectional height direction is 191,000 cm 4 or more; a ratio Iy / H of a cross-sectional height H (cm) to a second moment of area Iy (cm 4 ) about the strong axis is 5,210 cm 3 or more; A hat-shaped steel sheet pile having a length L of 25 m or less and a bending ratio r B calculated by formula (iii) of 0.7 or less.

4. The hat-shaped steel sheet pile according to any one of claims 1 to 3, wherein an effective width W of the hat-shaped steel sheet pile is 120 cm or more.

5. A manufacturing method of a steel sheet pile wall using the hat-shaped steel sheet pile according to any one of claims 1 to 3, A method for manufacturing a steel sheet pile wall, comprising: driving the hat-shaped steel sheet pile into the ground while fitting only one of the fitting joints of the hat-shaped steel sheet pile into the fitting joint of a steel sheet pile that has been driven in advance.

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