A detection body holder for confirming engagement of steel pipe sheet pile joints and a method for confirming engagement of steel pipe sheet pile joints using the same.

Abstract

To provide a detection body holder for confirming an engagement of a steel pipe sheet pile joint, which can accurately confirm the engagement state of the steel pipe sheet pile joint with a simple structure, and a method for confirming the engagement of the steel pipe sheet pile joint using the same.SOLUTION: This detecting body holder for confirming engagement state 20 consists of a pair of sensing body holding members 21 and 22 that are supported by a slit side edge of a fixed plate portion and have abutment portions 25 and 31 whose ends are abutted against each other. A detection wire 23 accommodated in a detection body accommodating portion consisting of detection body accommodating grooves 26, 27, 32, and 33 formed on outer peripheral surfaces of both the detection body holding members 21 and 22 is exposed between both abutment portions 25 and 31, and is held so as to cross a slit 6.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a detector holder for a steel pipe sheet pile joint for holding a detector used to check the engagement state of a steel pipe sheet pile joint that connects adjacent steel pipe sheet piles, and a method for checking the engagement of a steel pipe sheet pile joint using the same.

Background Art

[0002] As shown in FIG. 21, a continuous steel pipe sheet pile wall 1 used for a retaining wall or a steel pipe sheet pile shaft foundation is connected between adjacent steel pipe sheet piles 2, 2 through a joint structure (hereinafter referred to as a steel pipe sheet pile joint 3).

[0003] The steel pipe sheet pile joint 3 includes a pair of joint members 4, 5 supported on the outer peripheral ends of adjacent steel pipe sheet piles 2, 2, respectively. While engaging the joint member 5 of the subsequent steel pipe sheet pile 2 with the joint member 4 of the preceding steel pipe sheet pile 2, the subsequent steel pipe sheet pile 2 is driven to connect the adjacent steel pipe sheet piles 2, 2.

[0004] This type of steel pipe sheet pile joint has three standard structures: a so-called "P-T type" joint, a "P-P type" joint, and an "L-T type" joint, which are widely used.

[0005] As shown in FIG. 22, in the "P-T type" joint, one of the engaged joint members 4 is composed of a steel pipe (hereinafter referred to as a joint steel pipe 4). One end in the diameter direction of this joint steel pipe 4 is fixed to the outer peripheral surface of the steel pipe sheet pile 2 by welding or the like, and a slit portion 6 is formed along the vertical direction on the other end side.

[0006] The slit portion 6 is formed wider in the tangential direction than the thickness of a part of the other joint member 5 (hereinafter referred to as a support portion 7) described later, so that the support portion 7 can be inserted in the vertical direction.

[0007] The joint member 5 comprises a support portion 7 fixed to the outer circumference of the steel sheet pile 2 and an engaging portion 8 supported by the support portion 7. The support portion 7 and the engaging portion 8 form a T-shape in plan view, and the support portion 7 is inserted into the slit portion 6 of the joint steel pipe 4, and the engaging portion 8 is engaged with the joint steel pipe 4.

[0008] As shown in Figure 23, the "PP type" joint has joint steel pipes 9 and 10 fixed to the outer surfaces of two adjacent steel sheet piles 2 and 2, respectively, and the two joint steel pipes 9 and 10 are engaged with each other through slits 11 and 11 formed in the joint steel pipes 9 and 10.

[0009] As shown in Figure 24, the "LT type" joint comprises a pair of angle steels 12, 12 fixed to the outer circumferential surface of one adjacent steel sheet pile 2, and a T-shaped steel 5 supported on the outer circumferential surface of the other steel sheet pile 2. The support portion 7 of the T-shaped steel 5 is inserted into a slit portion 13 formed between the angle steels 12, 12 supported on one steel sheet pile 2, and the engaging portion 8 supported on the support portion 7 engages with both angle steels 12, 12.

[0010] In this type of steel pipe sheet pile joint, it is important that the joint members are properly engaged with each other from the standpoint of ensuring rigidity between the steel pipe sheet piles and ensuring watertightness, and it is desirable to confirm that the joint members are properly engaged with each other during construction.

[0011] On the other hand, as a technique for confirming the engagement state of joints connecting adjacent steel sheet piles, a detection wire made of an electric wire or the like is placed in the gap of the joint of the steel sheet pile that has been driven in earlier, and the engagement state is confirmed by the energization state of the detection wire (see, for example, Patent Document 1).

[0012] In this verification method using a detection wire, when the joint of a trailing steel sheet pile is inserted into the gap formed in the joint of a leading steel sheet pile, the joint of the trailing steel sheet pile comes into contact with the detection wire, cutting the detection wire. This causes the circuit containing the detection wire to change from a powered state to a de-powered state, thereby detecting that the joints of the steel sheet piles are properly engaged with each other. [Prior art documents] [Patent Documents]

[0013] [Patent Document 1] Japanese Patent Publication No. 2017-2710 [Overview of the project] [Problems that the invention aims to solve]

[0014] However, the joint structure of steel sheet piles is designed so that the width of the slit formed in the joint steel pipe or between the angle steels is larger than the width of the part into which the other joint member is inserted, compared to the gap in the joint structure of the steel sheet pile. This allows for a certain amount of movement of the other joint member within the slit, and thus absorbs positional displacement due to eccentricity when driving steel sheet piles.

[0015] Therefore, with the conventional technology described above, if the eccentricity within the slit of the other joint member is large, even if the joint members are properly engaged with each other, the position of the other joint member may deviate from the installation location of the detection body, and there is a risk that the detection wire will not be cut.

[0016] Furthermore, in order to avoid the problems described above, it is preferable that the detection wire is routed in a direction that crosses the slit so that the detection wire is reliably cut by the support part inserted into the slit.

[0017] However, in that case, the detection wire had to be laid along the outer or inner surface of the steel pipe used for the joint, and there was a risk that the detection wire would break due to ground penetration resistance or contact with gravel, etc., during or after the steel sheet pile was driven.

[0018] Therefore, in view of these conventional problems, the present invention aims to provide a detection body holder for confirming the engagement state of steel pipe sheet pile joints, and a method for confirming engagement using the same, which can accurately confirm the engagement state of steel pipe sheet pile joints with a simple structure. [Means for solving the problem]

[0019] The invention described in claim 1, which solves the conventional problems described above, is a detection body holder for confirming the engagement state of a steel pipe sheet pile joint, which holds a detection body for detecting the engagement state of a steel pipe sheet pile joint in which a part of the other joint member is inserted into a vertical slit formed in one joint member that connects adjacent steel pipe sheet piles, and the detection body holder comprises a pair of detection body holder members, each having a fixed plate portion fixed to the outer circumferential surface of one joint member adjacent to the slit portion, and a butt portion integrally supported at the slit portion side edge of the fixed plate portion, wherein a detection body housing portion is formed on the outer or inner circumferential surface of both detection body holder members, straddling the butt portion and the fixed plate portion, with the tip sides of the butt portions that abut against each other in contact, and the detection body housed in the detection body housing portion is exposed between the abutted ends of the two butt portions and is held so as to cross the slit portion.

[0020] The feature of the invention described in claim 2 is that, in addition to the configuration of claim 1, at least the upper portion of both butt joints is provided with tapered portions that are inclined toward the butted ends, so that a part of the other joint member inserted into the slit portion is guided between the butted ends of the two butt joints.

[0021] The feature of the invention described in claim 3 is that, in addition to the configuration of claim 1 or 2, the butt portion protrudes through the slit portion into the inside of one of the joint members, and its ends abut against each other.

[0022] The feature of the invention described in claim 4 is that, in addition to the configuration of claim 3, it is provided with a connecting plate that spans across the two detection body holding members, sandwiching the two abutting portions of the two detection body holding members that abut against each other.

[0023] The feature of the invention according to claim 5 is that, in addition to the configuration of claim 1 or 2, the detection body housing portion includes a pair of detection body housing grooves parallel to each other in the both detection body holding members, and a folded-back portion straddling between the detection body housing grooves formed in one of the detection body holding members, and the circumferential length of one of the detection body holding members is formed shorter than that of the other detection body holding member.

[0024] The feature of the invention according to claim 6 is that, in addition to the configuration of claim 1 or 2, a welding notch is formed in the peripheral edge of the fixed plate portion.

[0025] The feature of the invention according to claim 7 is that, in addition to the configuration of claim 1 or 2, the detection body is a coated electric wire whose outer periphery is coated with an insulator.

[0026] The feature of the invention according to claim 8 is that, in addition to the configuration of claim 1 or 2, the detection body is constituted by a thin plate-shaped electrode in which a conductive thin plate material is coated with an insulator.

[0027] The feature of the invention according to claim 9 is that, in addition to the configuration of claim 8, the thin plate-shaped electrode is fixed to the detection body holding member with an insulating bolt.

[0028] The features of the invention described in claim 10 are a method for detecting the engagement state of a steel pipe sheet pile joint in which a part of one joint member is inserted into a vertical slit formed in one joint member that connects adjacent steel pipe sheet piles, and the two joint members are engaged, comprising a pair of detection body holding members having a fixing plate portion fixed adjacent to the slit portion on the outer circumferential surface of one joint member and a butt portion integrally supported on the slit portion side edge of the fixing plate portion, wherein the outer or inner circumferential surfaces of both detection body holding members span the butt portion and the fixing plate portion and butt against each other The method involves first fixing a detection body holder, which has a detection body housing section formed by the tip of the abutting portion contacting the other joint member, to one of the joint members, housing the detection body in the detection body housing section so as to straddle the abutted ends of both abutting portions, and then, after driving one of the adjacent steel pipe sheet piles into the ground first, inserting a part of the other joint member into the slit portion while driving the other steel pipe sheet pile, the detection body is cut when a part of the other joint member passes between the abutted ends of both abutting portions, thereby detecting that the two joint members are engaged.

[0029] The feature of the invention described in claim 11 is that, in addition to the configuration of claim 10, a plurality of the detection body holders are fixed at intervals in the axial direction of one of the joint members.

[0030] The feature of the invention described in claim 12 is that, in addition to the configuration of claim 10 or 11, the detection body holder is fixed to one of the joint members in a state in which the two detection body holders are integrated via a connecting plate that is positioned across the two detection body holders, and the connecting plate is detached from or destroyed from between the two detection body holders by contacting a part of the other joint member that is inserted into the slit portion.

[0031] The feature of the invention described in claim 13 is that, in addition to the configuration of claim 10 or 11, an arc-shaped slit spacing holder is fixed above and / or below the detection body holder of one of the joint members so as to cross the slit portion, and the slit spacing holder comes into contact with a part of the other joint member that is inserted into the slit portion, thereby detaching from or being destroyed from the one joint member. [Effects of the Invention]

[0032] The detection body holder for confirming the engagement state of a steel pipe sheet pile joint according to the present invention, by having the configuration described in claim 1, can hold a detection body across the slit portion of a joint member having a slit portion, such as a steel pipe for joints, while preventing the detection body from being disconnected due to ground penetration resistance or contact with gravel, etc.

[0033] Furthermore, in the present invention, by having the configuration described in claim 2, a part of the other joint member inserted into the slit can be accurately guided to the position where the detection body is exposed.

[0034] Furthermore, in the present invention, by having the configuration described in claim 3, the portion of the detection body that is easily cut can be drawn into the joint member, and the detection body can be held so as to cross the slit portion while preventing the detection body from being cut due to ground penetration resistance or contact with gravel, etc.

[0035] Furthermore, by providing the configuration described in claim 4 of the present invention, it is possible to prevent the detection element from being disconnected when driving a steel sheet pile on which the engagement state confirmation detection element holder is located.

[0036] Furthermore, by incorporating the configuration described in claim 5, the detection body can be held compactly, while reducing material costs and suppressing an increase in penetration resistance. In addition, it can accommodate cases where the slit portion is positioned off-center on one side of the circumferential direction of the steel pipe for the joint, such as in so-called "PP type" joints.

[0037] Furthermore, in the present invention, by having the configuration described in claim 6, a sufficient welding length can be secured for fixing the retainer to the joint member.

[0038] Furthermore, by incorporating the configuration of claim 7 in the present invention, the fitting state during steel pipe sheet pile driving can be easily detected.

[0039] Furthermore, by incorporating the configuration described in claim 8 of the present invention, the detection body becomes less susceptible to damage during steel pipe sheet pile driving.

[0040] Furthermore, in the present invention, by having the configuration described in claim 9, if a malfunction occurs in the thin plate-shaped electrode, which is the detection body, before the steel pipe sheet pile is driven in, the thin plate-shaped electrode, which is the detection body, can be easily replaced.

[0041] Furthermore, by incorporating the configuration described in claim 10, the detection body can be installed at a desired position with a simple structure, and the engagement state of the joint member can be reliably detected.

[0042] Furthermore, in the present invention, by having the configuration described in claim 11, the engagement state of the joint members can be checked in stages during the subsequent driving of steel pipe sheet piles.

[0043] Furthermore, by providing the configuration described in claim 12, the detection body holder can be easily attached, and the detection body can be protected to prevent disconnection during the driving of the preceding steel pipe sheet pile and until the following steel pipe sheet pile is driven, and the engagement of joint members during the driving of the following steel pipe sheet pile is not hindered.

[0044] Furthermore, by providing the configuration described in claim 13, the deformation of the slit portion of the joint member due to ground penetration resistance during steel pipe sheet pile driving can be suppressed, and damage to the detection body held by the detection body holder can be prevented. [Brief explanation of the drawing]

[0045] [Figure 1] This is a perspective view showing how to use the detection body holder for confirming the engagement state of a steel pipe sheet pile joint according to the present invention. [Figure 2] This is a plan view of the same as above. [Figure 3] This is a front view showing the holder for the detection element used to confirm the engagement state, as described above. [Figure 4] This is a rear view of the same object. [Figure 5] This is a plan view of the same as above. [Figure 6] This is a right side view of the same object. [Figure 7] This is a left side view of the same object. [Figure 8] This is a cross-sectional view taken along line AA, as shown above. [Figure 9] This is a cross-sectional view taken along the line BB shown above. [Figure 10] This is a view taken along line AA in Figure 3, showing another embodiment of the same engagement state confirmation sensor holder. [Figure 11] This is a view taken along the line BB in Figure 3 above. [Figure 12] (a) is a perspective view showing the state when the detection body holder is attached using a connecting plate, and (b) is a perspective view showing another embodiment thereof. [Figure 13] A perspective view showing how the above-mentioned slit spacing holder is used. [Figure 14] This is a cross-sectional view showing the wiring status of the transmission line shown above. [Figure 15] This is an enlarged front view showing the state when the detection element shown above is disconnected. [Figure 16] This is a perspective view showing another embodiment of the detection object holder according to the present invention. [Figure 17] This is a partially enlarged perspective view showing yet another embodiment of the detection object holder according to the present invention. [Figure 18] This is a perspective view showing another aspect of the detection device. [Figure 19] A perspective view showing the above-mentioned detection object held in the detection object holder. [Figure 20] A side view of the same object. [Figure 21] This is a front view showing the state of a conventional steel pipe sheet pile wall during construction. [Figure 22] This is a cross-sectional view showing an example of a "PT type" joint, which is a steel pipe sheet pile joint. [Figure 23] This is a cross-sectional view showing the configuration of the "PP type" joint shown above. [Figure 24] This is a cross-sectional view showing the configuration of the "LT type" joint shown above. [Modes for carrying out the invention]

[0046] Next, an embodiment of the detection body holder for confirming the engagement state of steel pipe sheet pile joints according to the present invention will be described based on the example shown in Figures 1 to 9.

[0047] In this embodiment, a so-called PT-type steel pipe sheet pile joint will be used as an example, and components similar to those in the conventional example described above will be denoted by the same reference numerals and their explanation will be omitted.

[0048] Furthermore, reference numeral 15 in the figure indicates the tip shoe of the closing plate that closes the diagonally cut lower end of the steel pipe 4 for the joint.

[0049] As shown in Figures 1 and 2, the detection body holder for confirming the engagement state of steel pipe sheet pile joints (hereinafter referred to as the detection body holder 20) comprises a pair of detection body holder members (hereinafter referred to as the long detection body holder member 21 and the short detection body holder member 22) with different circumferential lengths fixed to the outer surface of the steel pipe 4 for the joint, sandwiching the slit portion 6. The detection body holder members 21 and 22 are configured to hold a detection line 23, which is a form of the detection body, across the slit portion 6.

[0050] Furthermore, the detection wire 23 is made of a coated wire whose outer circumference is covered with an elastic insulator such as resin. When the support portion 7 of the joint member 5 of the trailing steel sheet pile 2 comes into contact with the detection wire 23 and cuts the detection wire 23, the circuit having the detection wire 23 changes from a live state to a de-live state, thereby detecting that the joint portions of the steel sheet piles 2, 2 are properly engaged with each other.

[0051] The long detection body holding member 21 is made of a steel plate or the like and includes a fixing plate portion (hereinafter referred to as the long fixing plate portion 24) which is fixed to the outer surface of the joint steel pipe 4 adjacent to the slit portion 6, and a butt portion 25 which is supported at one end of the long fixing plate portion 24 (the edge on the slit portion 6 side).

[0052] The elongated fixing plate portion 24 has a constant width in the vertical direction and is formed in a substantially semi-circular arc shape with a circumferential length extending from the slit portion 6 to the position where it is supported by the steel sheet pile 2 of the joint steel pipe 4. The upper and lower edges are fixed to the outer circumference of the joint steel pipe 4 by welding. Alternatively, the elongated fixing plate portion 24 may be fixed to the joint steel pipe 4 by bolts or other fixing means instead of welding.

[0053] The butt joint portion 25 is formed in a trapezoidal shape with a tapered portion 25a that is inclined toward the tip end at least on its upper side, and extends diagonally inward from one end (the edge on the slit portion 6 side) of the elongated fixing plate portion 24. The tapered portion 25a may also be provided at the lower end of the butt joint portion 25.

[0054] Furthermore, a pair of parallel detection element housing grooves 26 and 27 are formed on the outer circumferential surface of the long detection element holding member 21, spaced apart in the vertical direction, allowing the detection wire 23 to be held in a state where it is housed within the detection element housing grooves 26 and 27.

[0055] These two detection body housing grooves 26 and 27 extend across the butt joint portion 25 and the elongated fixing plate portion 24, continuing along the entire circumferential direction of the elongated detection body holding member 21, and are formed as recessed grooves that open at both ends, i.e., the tip side of the butt joint portion 25 and the end face of the fixing plate portion opposite to the butt joint portion 25.

[0056] The depth of the detection element housing grooves 26 and 27 is formed to be at least the same as, or larger than, the diameter of the detection wire 23, so that the entire detection wire 23 can be routed within the grooves. If the groove width of the detection element housing grooves 26 and 27 is smaller than the diameter of the detection wire 23, the outer coating of the detection wire 23, such as resin, will be compressed and fitted into place when the detection wire 23 is routed through both detection element housing grooves 26 and 27. On the other hand, if the groove width of the detection element housing grooves 26 and 27 is larger than the diameter of the detection wire 23, the detection wire 23 can be fixed in place by filling the grooves with adhesive or the like.

[0057] The short-length detection body holding member 22 is made of a steel plate or the like and includes a fixing plate portion (hereinafter referred to as the short-length fixing plate portion 30) which is fixed to the outer surface of the joint steel pipe 4 adjacent to the slit portion 6, and a butt portion 31 which is supported at one end (the edge on the slit portion 6 side) of the short-length fixing plate portion 30.

[0058] The short fixing plate portion 30 has a constant width in the vertical direction, similar to the long fixing plate portion 24, and is formed in a semi-circular arc shape with a circumferential length shorter than the long fixing plate portion 24. Its upper and lower edges are fixed to the outer circumference of the joint steel pipe 4 by welding or other means. Alternatively, the short fixing plate portion 30 may be fixed to the joint steel pipe 4 by bolts or other fixing means instead of welding.

[0059] The circumferential length of the short fixing plate portion 30 only needs to have the necessary welding length to ensure sufficient strength to prevent it from coming off during casting, and other aspects are not particularly limited.

[0060] The butt joint 31 is formed in a trapezoidal shape with a tapered portion 31a that is inclined toward the tip end, at least on its upper side, and extends diagonally inward from one end (the edge on the slit portion 6 side) of the short fixing plate portion 30, forming a symmetrical shape when it is butted with the butt joint 25 of the long detection body holding member 21. The tapered portion 31a may also be provided on the lower side of the butt joint 31.

[0061] Furthermore, a pair of parallel detection body accommodating grooves 32 and 33 are formed on the outer circumferential surface of the short detection body holding member 22, spaced vertically apart at the same height as the detection body accommodating grooves 26 and 27 of the long detection body holding member 21.

[0062] These two detection body housing grooves 32 and 33 extend across the butt joint portion 31 and the short fixing plate portion 30, continuing along the entire circumferential direction of the short detection body holding member 22, and are formed as concave grooves that open at both ends, i.e., the tip side of the butt joint portion 31 and the end face of the short fixing plate portion 30 opposite to the butt joint portion 31.

[0063] The depth of the detection element housing grooves 32 and 33 is formed to be at least the same as, or larger than, the diameter of the detection wire 23, so that the detection wire 23 can be routed while housed within them. If the groove width of the detection element housing grooves 32 and 33 is smaller than the diameter of the detection wire 23, when the detection wire 23 is routed through both detection element housing grooves 32 and 33, the outer covering of the detection wire 23, such as resin, is compressed and fitted into place. On the other hand, if the groove width of the detection element housing grooves 32 and 33 is larger than the diameter of the detection wire 23, the detection wire 23 can be fixed in place by filling the grooves with adhesive or the like.

[0064] Furthermore, at the end of the short fixing plate portion 30 opposite to the butt joint portion 31, a rectangular folding notch 34 is formed between the ends of the two detection body housing grooves 32 and 33, penetrating in the thickness direction of the short fixing plate portion 30, and a folding portion 35 is provided within this folding notch 34.

[0065] The folded portion 35 comprises an elastic support piece 35a extending diagonally toward the outer circumferential surface from the inner edge of the folding notch 34, and a pressing portion 35b extending circumferentially from the tip of the elastic support piece 35a, forming a cantilever spring shape. However, the configuration of the folded portion 35 is not limited to this, and for example, as shown in Figure 12, the elastic support piece 35a and the pressing portion 35b may be omitted, and the ends of the two detection body housing grooves 32 and 33 provided in the short fixed plate portion 30 may be folded along the folding notch 34.

[0066] As shown in Figures 1 and 2, the detection element holder 20 configured in this way is fixed to both sides of the slit portion 6 of the joint steel pipe 4 by fixing the two fixing ramps 24 and 30 to each side, so that the two abutting portions 25 and 31 protrude through the slit portion 6 into the inside of the slit portion 6 of the joint steel pipe 4, and the tips of the abutting portions 25 and 31 abut against each other, and a detection element housing portion is formed by the detection element housing grooves 26, 27, 32, 33 and the folding notch portion 34, where the tips of the abutting portions 25 and 31 abut against each other, and the detection wire 23, which is the detection element, is housed in this detection element housing portion.

[0067] Then, the detection wire 23, which is routed within one of the detection body housing grooves 26 of the long detection body holding member 21, passes through the tip-side opening of the butt joint 25 and reaches into one of the detection body housing grooves 32 of the short detection body holding member 22 through the tip-side opening of the butt joint 31 of the butted short detection body holding member 22. By hooking it onto the inner circumferential surface side of the folded-back portion 35, it is folded back towards the other detection body housing groove 33. The detection wire 23 passes through the other detection body housing groove 33 of the short detection body holding member 22 and is then stretched across to the tip-side opening of the butt joint 25 of the long detection body holding member 21 that is butted from the tip-side opening of the butt joint 31. From the butt joint 25, it reaches into the other detection body housing groove 27 of the long detection body holding member 21, allowing it to be routed to the vicinity of the steel pipe sheet pile 2.

[0068] Next, a method for confirming the engagement state of a joint using the detection body holder 20 described above will be explained.

[0069] First, multiple engagement state confirmation sensor holders (hereinafter referred to as sensor holders 20) are fixed to the outer surface of one joint member (joint steel pipe 4) of the steel sheet pile 2 that is to be driven in first, at intervals in the vertical direction (pipe axis direction).

[0070] Furthermore, the installation position of each detection body holder 20 is preferably at least at the lower end of the joint pipe 4 in order to confirm that the other joint member 5 (support part 7) has reached the lower end (near the deepest part in the vertical direction) of the joint pipe 4 relative to one joint member (joint steel pipe 4). In order to observe the progress along the way, one or more detection body holders 20 may also be installed in the middle of the joint steel pipe 4.

[0071] Each detection body holder 20 is fixed by securing the fixing ramps 24 and 30 of the long detection body holder member 21 and the short detection body holder member 22 to both sides of the slit portion 6 of the joint steel pipe 4, respectively. As a result, the abutting portions 25 and 31 protrude through the slit portion 6 into the inside of the joint steel pipe 4, and the tips of the abutting portions 25 and 31 abut each other.

[0072] As shown in Figure 1, the fixed ramp sections 24 and 30 are fixed to the outer surface of the joint steel pipe 4 by welding or the like at their upper and lower edges, respectively.

[0073] Furthermore, when fixing the detection body holder 20 to the steel pipe 4 for the joint, as shown in Figure 12(a), the two detection body holders 21 and 22 may be fixed together as a single unit via a connecting plate 40 that is positioned across the two detection body holders 21 and 22.

[0074] The connecting plate 40 is formed from a steel plate or the like in the shape of a short plate shorter than the distance from the lower detection body housing grooves 27, 33 to the lower edges of the detection body holding members 21, 22, and is fixed to the surfaces of the abutting portions 25, 31 by welding or the like at positions where both side edges do not overlap with the detection body housing grooves 27, 33.

[0075] The connecting plate 40 and the abutting portions 25, 31 (detection body holding members) are fixed with a strength such that they detach from the two detection body holding members 21, 22 by contacting the support portion 7 inserted into the slit portion 6.

[0076] Alternatively, as shown in Figure 12(b), the connecting plate 40 may have vertical cutting assist grooves 41 formed on its surface, and when it comes into contact with the support portion 7 inserted into the slit portion 6, the portion that has been thinned by the cutting assist grooves 41 may be cut in half by the support portion 7.

[0077] Furthermore, without using the connecting plate 40, the two detection body holding members 21 and 22 can also be integrated by welding the ends of the butt joints 25 and 31, which are abutted against each other, to a strength sufficient to separate them from each other by contacting the support part 7.

[0078] Furthermore, since the slit portion 6 of the joint steel pipe 4 may deform due to ground penetration resistance, etc., as shown in Figure 13, an arc-shaped slit spacing holder 54 may be fixed below the detection body holder 20 on the outer surface of the joint steel pipe 4 so as to cross the slit portion 6, thereby preventing deformation of the slit portion 6.

[0079] The slit spacing holder 54 may be formed in the shape of an arc plate from a steel plate or the like, with vertical cutting assist grooves 55 formed on its surface, so that when it comes into contact with the support part 7 inserted into the slit part 6, the thinned portion caused by the cutting assist grooves 55 is cut in half by the support part 7, or it may be welded to the joint steel pipe 4 so that it detaches from the joint steel pipe 4 when it comes into contact with the support part 7.

[0080] Furthermore, the slit spacing holder 54 may be provided above the detection body holder 20 on the outer surface of the steel pipe 4 for the joint, or it may be provided both above and below.

[0081] Next, the detection wire 23 is routed through the detection body housing groove 26, and the detection wire 23 is positioned to cross the slit portion 6 while exposed between the ends of the two butt joint portions 25 and 31.

[0082] Specifically, with both ends of the detection wire 23 left over on the steel pipe sheet pile 2 side of the long detection body holding member 21, the detection wire 23 is routed through the detection body housing groove 26 on one (upper) side of the long detection body holding member 21, and then routed to the tip-side opening of the abutting portion 25 of the long detection body holding member 21.

[0083] Next, the detection wire 23, which has passed through the tip-side opening of the butt joint 25 of the long detection body holding member 21, is introduced through the tip-side opening of the butt joint 31 of the short detection body holding member 22 that is butted against it, and is routed into the detection body housing groove 32 on one side (upper side) of the short detection body holding member 22.

[0084] Then, by hooking the detection wire 23 onto the inner circumferential surface side of the folded portion 35, it is folded back towards the other (lower) detection body housing groove 33, and the detection wire 23 is routed through the other detection body housing groove 33 of the short detection body holding member 22 to the tip side opening of the abutting portion 31.

[0085] Finally, the detection wire 23, which has passed through the tip opening of the butt joint 31 of the short detection body holding member 22, is introduced through the tip opening of the butt joint 25 of the long detection body holding member 21 that is butted against it, and is routed into the detection body housing groove 27 on the other (lower) side of the long detection body holding member 21, and then routed to the vicinity of the steel pipe sheet pile 2.

[0086] If the detection wire 23 has excess length, the excess portion is wrapped around the reel rod 44 protruding from the outer surface of the steel pipe sheet pile 2, or the detection wire 23 is cut to adjust it to a suitable length.

[0087] If the diameter of the detection wire 23 is larger than the width of the detection body housing grooves 26, 27, 32, and 33, the detection wire 23 is pushed into the groove, causing the outer covering 23a to be pressed against the side walls of the detection body housing grooves 26 and 27, compressing and fixing it in place. If the diameter of the detection wire 23 is smaller than the width of the detection body housing grooves 26, 27, 32, and 33, the detection wire 23 is fixed into the groove with adhesive.

[0088] Furthermore, if necessary, protective tape materials such as glass cloth tape or butyl rubber tape may be applied to cover the surface of the detection element housing grooves 26, 27, 32, and 33 to protect the detection wire 23. Alternatively, strip-shaped protective members may be attached at intervals in the circumferential direction, straddling each of the upper and lower detection element housing grooves 26, 27, 32, and 33, to protect and secure the detection wire 23.

[0089] Next, the transmission line 43 is pulled out from the end of the long detection line holding member 21 on the steel pipe sheet pile 2 side, along the steel pipe sheet pile 2, to the upper position of the steel pipe sheet pile 2, at least after the steel pipe sheet pile 2 has been driven, so that it reaches the water surface or the ground.

[0090] The conductive transmission line 43, which is connected to the detection line 23 and covered with an insulator, is installed in the space formed inside the flat bar 48 that is installed across the steel sheet pile 2 and the joint steel pipe 4, as shown in Figure 14, and is fixed in place by filling the gap with urethane 49 or the like.

[0091] Furthermore, the installation of the transmission line 43 is not limited to the above-described embodiment. For example, although not specifically shown, it may be fixed between the steel sheet pile 2 and the joint steel pipe 4 using only a hardening material such as adhesive without using a flat bar 48. Alternatively, a structure commonly used when attaching sensors such as strain gauges to the steel sheet piles 2, 2 may be used, specifically a general structure in which a protector made of channel steel or the like is provided on the outer surface of the steel sheet pile 2, and the transmission line 43 is placed inside the protector.

[0092] Then, both ends of the detection wire 23, including the end that has been wrapped around the reel rod 44 or cut off, are connected to the transmission wire 43, and the other end of the transmission wire 43 is connected to an engagement state detection means installed on the ground or on the water surface.

[0093] The engagement state detection means, although not specifically shown in the figures, for example, energizes the detection line 23 via the transmission line 43, and detects that the joint members 4 and 5 are engaged when the detection line 23 is cut and becomes de-energized.

[0094] Furthermore, the non-energized state can be confirmed by current and voltage values, or by the blinking of a light bulb or similar device. In addition to the above-mentioned change in energization / non-energization, the detection method may also be based on changes in stress acting on the detection object.

[0095] Next, once the detection device holder 20 and detection wire 23 are secured, the lead steel pipe sheet pile 2 is driven into the ground.

[0096] In this configuration, the detection wire 23 is held by the detection body holder 20 while housed within the detection body housing section formed by the detection body housing grooves 26, 27, 32, 33 and the folding notch 34. Furthermore, the portion of the detection wire 23 exposed between the two butt joints 25, 31 is located inside the joint steel pipe 4 through the slit 6. As a result, the detection wire 23 is not exposed outside the joint steel pipe 4, preventing the detection wire 23 from being broken due to penetration resistance from the ground or contact with gravel, etc.

[0097] Then, once the driving of the preceding steel pipe sheet pile 2 is complete, the driving of the trailing steel pipe sheet pile 2 is carried out next. If, after driving the trailing steel pipe sheet pile 2, the engagement of the steel pipe sheet pile joints is to be checked when driving the next steel pipe sheet pile (trailing steel pipe sheet pile), a detection line 23 is installed on the trailing steel pipe sheet pile 2 in the same way as the preceding steel pipe sheet pile 2.

[0098] When driving the trailing steel pipe sheet pile 2, the support part 7 is aligned with the position of the slit part 6 of the steel pipe 4 so that the engaging part 8 of the joint member 5 is positioned inside the steel pipe 4 for the joint, and the two joint members 4 and 5 are engaged while driving them downwards in that state.

[0099] As the driving of the trailing steel pipe sheet pile 2 progresses with both joint members 4 and 5 engaged, the support part 7 descends with the support part inserted into the slit part 6, reaching the position where the detection body holder 20 is installed. Furthermore, since the locations where the detection body holder 20 and detection wire 23 are fixed on the leading steel pipe sheet pile 2 are known, the timing for confirming the engagement of the joint can also be determined by measuring the driving depth of the trailing steel pipe sheet pile 2.

[0100] As shown in Figure 15, the support portion 7, upon reaching the position of the detection body holder 20, contacts the tapered portions 25a and 31a formed on the upper edges of the abutting portion 25, and is guided by the tapered portions 25a and 31a to a position between the two abutting portions 25 and 31.

[0101] Then, as it descends further, it pushes the two abutting parts 25 and 31 apart and is inserted between them, making contact with the detection wire 23 exposed between the tips of the two abutting parts 25 and 31, and cutting the detection wire 23.

[0102] At that time, the detection wire 23, which was energized, is cut, causing the circuit including the detection wire 23 to become de-energized, and the detection means detects that the support part 7 has passed through the slit part 6 at the position where the detection body holder 20 is installed.

[0103] Furthermore, if both detection body holding members 21 and 22 are integrated via a connecting plate 40, the support portion 7 will come into contact with the connecting plate 40, and the load acting on the support portion 7 will cause the connecting plate 40 to detach from or break the two detection body holding members 21 and 22.

[0104] Then, the support portion 7, upon reaching the lower end, cuts the detection wire 23 held by the detection body holder 20 installed at the lower end, thereby detecting that both joint members 4 and 5 are properly engaged up to the lower end.

[0105] In this method for confirming the engagement of a steel pipe sheet pile joint, the detection wire 23 is held by the detection body holder 20, allowing the detection wire 23 to be routed across the slit portion 6. Therefore, even if the support portion 7 moves eccentrically relative to the slit portion 6, the engagement state can be reliably confirmed.

[0106] Furthermore, by housing the detection wire 23 within the detection body housing portion of the detection body holder 20, and exposing the detection wire 23 only between the two butt joint portions 25 and 31 that protrude into the steel pipe 4 through the slit portion 6, the detection wire 23 is not affected by penetration resistance or gravel when driving in the steel sheet pile 4, and the detection wire 23 is suitably protected from driving in until the support portion 7 is inserted into the slit portion 6.

[0107] In the above-described embodiment, a so-called "PT type" joint was used as an example, but the present invention can also be applied to "PP type" and "LT type" joints.

[0108] When used with "PP type" joints, the above-described detection element holder 20 can be used as is. Furthermore, since tapered portions 25a and 31a are provided on the upper and lower sides of the butt joint portions 25 and 31, respectively, the detection element holder 20 can also be fixed to the other joint steel pipe 10 by flipping it upside down.

[0109] In the "LT type" joint, this can be achieved by forming the fixing plate portion to match the shape of the angle steel 12,12.

[0110] Furthermore, although the shapes of the fixing plate portions 24 and 30 are shown as rectangular in side view in the above embodiments, the embodiments are not limited to those described above. For example, as shown in Figure 16, welding notches 50, 50 may be formed on the periphery of the fixing plate portions 24 and 30 to ensure a long welding length and secure the fixing firmly.

[0111] Furthermore, the fixing of the fixing plates 25 and 30 is not limited to welding; for example, they may be attached using adhesive tape or glue, or fixed with bolts.

[0112] Furthermore, although the detection grooves 26, 27, 32, and 33 are provided on the outer circumferential side of the long fixing section 24 and the short fixing section, they may also be provided on the inner circumferential side. In that case, the open surfaces of the detection grooves 26, 27, 32, and 33 are covered by the steel pipe 4 for the joint, thereby protecting the detection wire 23 during concrete casting.

[0113] Furthermore, although the above-described embodiment described a case in which the detection object holder 20 is composed of a long detection object holder member 21 and a short detection object holder member 22 as separate components, the detection object holder 20 may also be in a form in which the long detection object holder member 21 and the short detection object holder member 22 are integrated in a separable state.

[0114] Furthermore, in order to facilitate the optimal connection between the detection line 23 and the transmission line 43, as shown in Figure 17, detection pull-out grooves 51 and 52 may be provided on the long detection body holding member 21, extending upward from the side end opposite to the abutting portion 25 of the detection body housing grooves 26 and 27 formed horizontally.

[0115] Furthermore, although the case in which the detection element housing grooves 26, 27, 32, and 33 are provided on the outer circumferential surfaces of both detection element holding members 21 and 22 has been described, if the detection element housing grooves 26, 27, 32, and 33 are provided on the inner circumferential surfaces of both detection element holding members 21 and 22, the detection wire 23 is first fixed into the detection element housing grooves 26, 27, 32, and 33, and then both detection element holding members 21 and 22 are fixed to the predetermined positions of the joint steel pipe 4 by welding or the like.

[0116] Furthermore, although the above-described embodiment described a case in which a detection wire 23 made of an insulated electric wire was used as the detection body, the form of the detection body is not limited to this, and for example, an optical fiber may be used. In that case, the transmission line 43 should be made of an optical fiber that is suitable for the form of the detection body.

[0117] Furthermore, as an alternative form of the detection body, as shown in Figures 18 to 20, a thin plate-shaped electrode 60 made of a conductive plate material covered with an insulator may be used and held in a detection body holder 61 adapted to it.

[0118] As shown in Figure 18, the thin plate electrode 60 comprises a pair of narrow plate portions 60a, 60a arranged parallel to each other, and a connecting band portion 60b that connects one end of both narrow plate portions 60a, 60a, forming a U-shape, and a pair of transmission lines 62, 62 are connected to the ends of the narrow plate portions 60a, 60a opposite to the connecting band portion 60b.

[0119] The conductive thin sheet material is formed in a U-shape from a conductive material such as phosphor bronze or aluminum, can be deformed into an arc shape in the thickness direction, and has a thickness that allows it to be cut by a support part 7 inserted into the slit part 6.

[0120] This conductive thin plate material has multiple bolt insertion holes 67, 67… arranged at intervals along each narrow plate portion 60a, 60a, and elongated bolt insertion holes 68, 68 arranged in the connecting band portion 60b. Bolts 69 are passed through the bolt insertion holes 67 and 68, and the narrow plate portions 60a, 60a and the connecting band portion 60b are fixed to the detection body holder 61 by the bolts 69, with the slit portion 6 in between.

[0121] The bolt insertion hole 67 is formed as a round hole with a diameter approximately the same as or slightly larger than the threaded portion diameter of the bolt 69, so that the narrow plate portions 60a, 60a can be securely fixed to the long detection body holding member 21.

[0122] On the other hand, the bolt insertion hole 68 is formed as an elongated hole that is long in the circumferential direction of the detection body holder 61 to which it is attached. Even if the slit portion 6 deforms and the width of the slit portion 6 changes, the plate-shaped electrode 60 (connecting band portion 60b) and the short detection body holder member 22 can slide relative to each other by the length of the elongated hole, thereby absorbing the deformation of the slit portion 6.

[0123] In the above embodiment, the bolt insertion hole 67 was made into a round hole, but the bolt insertion hole 67 may also be formed into an elongated hole that is long in the circumferential direction of the detection body holder 61 to which it is attached, similar to the bolt insertion hole 68.

[0124] The bolt 69 is made of metal, resin, or the like, and is of a low-profile type so that its head does not protrude from the detection body housing. If the bolt 69 is to have insulating properties, it may be made of an insulating material other than resin, or its surface may be coated with an insulating material.

[0125] The insulator covering the conductive thin plate material is made of an insulating synthetic resin such as epoxy resin or urethane resin, and is designed to cover the surface of the conductive thin plate material and the inner circumferential surface of the bolt insertion hole.

[0126] As shown in Figures 19 and 20, the detection body holder 61 that holds the thin plate-shaped electrode 60 comprises a pair of detection body holder members (hereinafter referred to as the long detection body holder member 21 and the short detection body holder member 22) with different circumferential lengths fixed to the outer surface of the steel pipe 4 for the joint, sandwiching the slit portion 6. The thin plate-shaped electrode 60 is held across both detection body holder members 21 and 22, and the detection body, which is the thin plate-shaped electrode 60, is held so as to cross the slit portion 6. Components similar to those in the above embodiment will be denoted by the same reference numerals.

[0127] In this detection device holder 61, the abutting portions 25 and 31 are shaped to extend circumferentially from the ends of the respective fixing plate portions 24 and 30 on the slit portion 6 side, and the tips of both abutting portions 25 and 31 abut each other on the front side of the slit portion 6.

[0128] On the outer circumferential surface of the elongated detection body holding member 21, a pair of parallel detection body housing grooves 63, 64 are formed, spaced apart in the vertical direction, to accommodate the narrow plate portions 60a, 60a.

[0129] Furthermore, a folded portion 66 is formed on the outer circumferential surface of the short specimen holding member 22, spanning between the abutting ends of the detection body housing grooves 63 and 64. The abutting portions 25 and 31 are brought together to form a continuous detection body housing section. Together with the detection body housing grooves 63 and 64, the tip ends of the abutting portions 25 and 31 of the U-shaped recessed grooves come into contact, forming a detection body housing section in which the thin plate-shaped electrode 60 is held between the two detection body holding members 21 and 22 while housed within the detection body housing section.

[0130] The bottom of the detection body housing section, which consists of detection body housing grooves 63, 64 and a folded portion 66, has screw holes (not shown) formed in accordance with the positions of bolt insertion holes 67 and 68, so that the thin plate-shaped electrode 60 can be fixed by bolts 69.

[0131] Therefore, in this embodiment, since the thin plate electrode 60 is fixed to the detection body holder 61 by bolts 69, if a problem occurs with the thin plate electrode 60, which is the detection body, before the steel pipe sheet pile 2 is driven in, the thin plate electrode 60, which is the detection body, can be easily replaced.

[0132] Furthermore, the configuration of the detection body holder 20 is not limited to the above-described embodiment, and its dimensions can be appropriately set according to various circumstances such as the diameter of the joint steel pipe 4, the position of the slit portion 6, the connection between the detection wire 23 and the transmission wire 43, and the means for fixing it to the joint steel pipe 4. [Explanation of symbols]

[0133] 20 Detector Holder 21 Long detection body holding member 22 Short-length detection body holding member 23 detection lines 24 Long fixing plate section 25 Butt joint 26,27 Detector housing groove 30 Short fixing plate section 31 Butt joint 32,33 Detector housing groove 34 Folding notch 35 Folded section 40 Connecting Plates 41 Cutting auxiliary groove 42 connectors 43 Transmission lines 44 Reel Probe 48 Flat Bar 49 Urethane 50 Welding notches 51, 52 Detection element pull-out groove 54 Slit spacing holder 55 Cutting auxiliary groove 60 Thin plate electrode 61 Detector Holder 62 transmission lines 63 Detector housing groove 64 Detector housing groove 66 Folded section 67 Bolt insertion holes 68 Bolt insertion holes 69 volts

Claims

1. A detection body holder for confirming the engagement state of a steel pipe sheet pile joint, which holds a detection body for detecting the engagement state of a steel pipe sheet pile joint in which a part of the other joint member is inserted into a vertical slit formed in one joint member that connects adjacent steel pipe sheet piles, and the two joint members are engaged in that state, It consists of a pair of sensing element holding members, each comprising a fixing plate portion fixed to the outer circumferential surface of one of the aforementioned joint members adjacent to the slit portion, and a butt portion integrally supported at the slit portion side edge of the fixing plate portion. A detection body housing portion is formed on the outer or inner circumferential surface of both detection body holding members, straddling the abutting portion and the fixing plate portion, with the leading edges of the abutting portions abutting against each other. A detection body holder for confirming the engagement state of a steel pipe sheet pile joint, characterized in that the detection body housed within the detection body housing portion is exposed between the abutted ends of the two abutting portions and is held so as to cross the slit portion.

2. A detection body holder for confirming the engagement state of a steel pipe sheet pile joint according to claim 1, wherein at least the upper side of both abutting portions is provided with tapered portions that are inclined toward the abutted ends, and a part of the other joint member inserted into the slit portion is guided between the abutted ends of the two abutting portions by the tapered portions.

3. The abutting portion protrudes to the inside of one of the joint members through the slit portion, and the ends are abutted against each other, as described in claim 1 or 2, for the detection body holder for confirming the engagement state of a steel pipe sheet pile joint.

4. The detection body holder for confirming the engagement state of a steel pipe sheet pile joint according to claim 3, further comprising a connecting plate positioned between the two detection body holders, sandwiching the two abutting portions of the two detection body holders that abut each other.

5. The detection body housing portion comprises a pair of detection body housing grooves parallel to each other in both detection body holding members, and a folded portion formed in one of the detection body holding members that spans between the detection body housing grooves, wherein the circumferential length of one of the detection body holding members is shorter than that of the other detection body holding member, and the detection body holder for confirming the engagement state of a steel pipe sheet pile joint according to claim 1 or 2.

6. The fixing plate portion has welding notches formed on its peripheral edge, the detection body holder for confirming the engagement state of a steel pipe sheet pile joint according to claim 1 or 2.

7. The detection body holder for confirming the engagement state of a steel pipe sheet pile joint according to claim 1 or 2, wherein the detection body is a coated electric wire whose outer circumference is covered with an insulator.

8. The detection body holder for confirming the engagement state of a steel pipe sheet pile joint according to claim 1 or 2, wherein the detection body is composed of a thin plate electrode made of a conductive thin plate material covered with an insulator.

9. The detection body holder for confirming the engagement state of a steel pipe sheet pile joint according to claim 8, wherein the thin plate-shaped electrode is fixed to the detection body holding member with an insulating bolt.

10. In a method for confirming the engagement state of a steel pipe sheet pile joint, in which a part of one joint member is inserted into a vertical slit formed in one joint member that connects adjacent steel pipe sheet piles, the engagement state of the steel pipe sheet pile joint is detected, The detection body holding member comprises a pair of detection body holding members, each having a fixing plate portion fixed to the outer circumferential surface of one of the joint members adjacent to the slit portion, and a butt portion integrally supported at the slit portion side edge of the fixing plate portion. The detection body holding device is pre-fixed to the one joint member, with a detection body housing portion formed by the tip sides of the butt portions abutting against each other and straddling the butt portion and the fixing plate portion, and the detection body is housed in the detection body housing portion so as to straddle the butt ends of the two butt portions. After driving one of the adjacent steel sheet piles into the ground first, when driving the other steel sheet pile while inserting a part of the joint member of the other steel sheet pile into the slit, A method for confirming the engagement state of a steel pipe sheet pile joint, characterized in that the detection body is cut when a part of the other joint member passes between the abutted ends of the two abutting portions, thereby detecting that the two joint members are engaged.

11. A method for confirming the engagement state of a steel pipe sheet pile joint according to claim 10, wherein a plurality of the detection body holders are fixed at intervals in the axial direction of one of the joint members.

12. A method for confirming the engagement state of a steel pipe sheet pile joint according to claim 10 or 11, wherein the two detection body holding members are integrated via a connecting plate positioned across the two detection body holding members, and the detection body holder is fixed to one of the joint members, and the connecting plate comes into contact with a part of the other joint member inserted into the slit portion, causing it to detach from or be destroyed between the two detection body holding members.

13. A method for confirming the engagement state of a steel pipe sheet pile joint according to claim 10 or 11, wherein an arc-shaped slit spacing holder is fixed above and / or below the detection body holder of one of the joint members so as to cross the slit portion, and the slit spacing holder comes into contact with a part of the other joint member inserted into the slit portion, causing it to detach from or be destroyed from the one joint member.

Images