Segment joint for steel segment

Abstract

To provide a segment joint for a steel segment, which can easily perform connecting work as a segment joint and can ensure reliable connecting strength and watertightness as a segment joint for the steel segment.SOLUTION: The present invention is a segment joint for a steel segment for connecting steel segments in the circumferential direction of a tunnel, the segment joint comprising a pair of main girders 3 extending in the circumferential direction of the tunnel, a pair of joint plates 2 connecting the main girders 3 extending in the tunnel axial direction, and a skin plate provided on the tunnel natural ground side. A main girder protrusion 4 protruding outward in the circumferential direction from the joint plate 2 is provided at the end of the main girder 3 of one of the segments 1 to be connected to each other, and a main girder notch 5 into which the main girder protrusion 4 fits is provided at the end of the main girder 3 of the other segment 1. The main girder protrusion 4 and the main girder notch 5 are fitted together from the tunnel axial direction, and have a trapezoidal dovetail shape that prevents them from slipping out in the circumferential direction of the tunnel, and a taper is provided on a fitting surface where the main girder protrusion 4 and the main girder notch 5 come into contact.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a joint of steel segments, particularly to a structure of a segment joint for connecting segments constituting a segment ring in the circumferential direction of the ring.

Background Art

[0002] Conventionally, for joints of steel segments, both ring joints (joints between rings) and segment joints (joints between segments) generally use bolt-type joints with bolts for joining.

[0003] However, in the case of bolt-type joints, since it is necessary to manage a large number of bolts used for joining segments and tighten a large number of bolts during construction, for ring joints, similar to the case of RC segments, for example, one-touch type or one-push type ring joints by fitting male and female joints have been developed.

[0004] Also, for segment joints, similar to the case of RC segments, various joint structures that do not require bolts, such as cotter joints, have been developed, and a one-pass construction method that can simultaneously join ring joints and segment joints has also been developed.

[0005] Patent Document 1 discloses a boltless coupling type steel segment that does not use bolts, in which a protruding portion of the main girder end protruding from the joint plate of the segment joint and the abutting plates at positions recessed from the joint plate are overlapped and connected by a mortise joint.

[0006] In Patent Document 2, in the same segment joint structure, with the aim of providing a segment that has sufficient endurance against the pressure of the propulsion jack during connection, has a strong connection structure, and enables easy connection work, one end of the web constituting the main girder is connected to the stepped-side connection plate via a stepped-side partition plate, while the other end is connected to the protruding-side connection plate via a protruding-side partition plate. That is, the web of the main girder is configured to be spaced apart in the tunnel axis direction from the stepped-side connection plate and the protruding-side connection plate and not flush.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0008] In the segment joints described in the above Patent Documents 1 and 2, a fitting hole is provided in the extension part of the main girder, and a protruding part that constitutes a ridge formed on the main girder or the protruding-side partition plate is fitted. However, when connecting segments, it is difficult to align the protruding part with the fitting hole. Also, if the diameter of the fitting hole is increased to provide a clearance to facilitate the fitting work, there is a problem that the water tightness is impaired.

[0009] Also, in the engagement between the protruding part corresponding to the plate thickness of the main girder and the fitting hole, there is a risk that the stress transmission as a segment joint becomes insufficient.

[0010] The present invention aims to solve the above-mentioned problems in the prior art, and provides a segment joint for steel segments that enables easy connection work as a segment joint, ensures reliable connection strength, and can prevent water leakage.

Means for Solving the Problems

[0011] In a segment joint of steel segments for connecting steel segments provided with a pair of main girders extending in the tunnel circumferential direction, a pair of joint plates extending in the tunnel axial direction and connecting between the main girders, and a skin plate provided on the tunnel ground side in the tunnel circumferential direction, a main girder protruding portion protruding outward in the circumferential direction from the joint plate is provided at the end of the main girder of one segment to be connected to each other, and a main girder notch portion into which the main girder protruding portion fits is provided at the end of the main girder of the other segment. The main girder protruding portion and the main girder notch portion are fitted from the tunnel axial direction and have a trapezoidal ant groove shape that prevents escape in the tunnel circumferential direction, and a taper is provided on the fitting surface where the main girder protruding portion and the main girder notch portion contact.

[0012] In the segment joint of the steel segments of the present invention, by making the shapes of the main girder protruding portion and the main girder notch portion into an ant groove shape that is fitted from the tunnel axial direction and prevents escape in the tunnel circumferential direction, it is possible to resist the tensile force generated in the segment joint within the segment ring, and smooth stress transmission can be achieved. Also included is the case where the corner of the trapezoidal ant groove shape is R-shaped.

[0013] By providing a taper on the fitting surface where the main girder protruding portion and the main girder notch portion contact, it becomes easier for the main girder protruding portion to slide and move the main girder notch portion. Also, by providing a taper on the fitting surface where the main girder protruding portion and the main girder notch portion contact, the cross-sections of the protruding portion of the main girder protruding portion and the notch portion of the main girder notch portion also become trapezoidal, and the effect of being easier to fit than when no taper is provided is obtained.

[0014] In addition, in the segment joint of the steel segment of the present invention, the width of the main girder notch portion in the longitudinal direction of the main girder is larger than the width of the main girder protruding portion in the longitudinal direction of the main girder. In the fitting state of the main girder protruding portion and the main girder notch portion, a gap is preferably formed between the rear end portion of the main girder notch portion in the longitudinal direction of the main girder and the tip end portion of the main girder protruding portion in the longitudinal direction of the main girder.

[0015] Conventionally, when the segment joints are fitted, there has sometimes been a gap in the straight edge portions on the side of the main girder notch portion and the side of the main girder protruding portion, which has caused water leakage. However, in the present invention, a gap is formed between the rear end portion of the main girder notch portion in the longitudinal direction of the main girder and the tip end portion of the main girder protruding portion in the longitudinal direction of the main girder, so that no gap occurs in the straight edge portions on the side of the main girder notch portion and the side of the main girder protruding portion.

[0016] In addition, the main girder notch portion is formed at the end of the main girder, and a reinforcing plate is preferably provided on the inner surface side of the segment of the main girder notch portion. The presence of the reinforcing plate makes it difficult for the main girder protruding portion and the main girder notch portion to come off, and can also supplement the strength of the fitting portion.

[0017] In addition, when the main girder protruding portion and the main girder notch portion are fitted, if they have the same thickness, it is conceivable that the main girder protruding portion will slightly lift up and a step will occur between the main girder protruding portion and the main girder notch portion. Therefore, for example, if the thickness of the reinforcing plate is pre-processed to provide a recess for the main girder protruding portion to fit into, no step will occur on the surface when the main girder protruding portion and the main girder notch portion are fitted.

[0018] For example, as a specific form of the reinforcing plate provided in the main girder notch portion, a structure can be used in which a connecting plate having the same or approximately the same thickness as the main girder is attached by welding or the like inside the main girder notch portion formed so that the main girder protruding portion of the other segment to be connected can be inserted.

Effects of the Invention

[0019] If the shapes of the main girder protrusion and the main girder notch are made into a shape like an ant groove that is fitted from the tunnel axis direction and the escape in the tunnel circumferential direction is prevented, it is possible to resist the tensile force generated in the segment joint within the segment ring at the fitting portion, and smoother stress transmission can be achieved.

[0020] A gap is formed between the rear end portion in the longitudinal direction of the main girder of the main girder notch and the front end portion in the longitudinal direction of the main girder of the main girder protrusion, so that no opening occurs in the end straight portions on the main girder notch side and the main girder protrusion side.

[0021] By providing a supplementary stiffening plate on the inner surface side of the segment of the main girder notch, it becomes difficult for the main girder protrusion to come out from the main girder notch, and the strength of the fitting portion can also be supplemented. Further, by processing the plate thickness of the supplementary stiffening plate, it is possible to prevent a step from occurring at the fitting portion between the main girder notch and the main girder protrusion.

Brief Description of the Drawings

[0022]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0023] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an enlarged view showing a fitting portion in an embodiment of the segment joint of the present invention. (a) is a front view showing the state after fitting, (b) is a front view and an A cross-sectional view showing the main girder notch portion 5 (female side joint), and (c) is a front view and a B cross-sectional view showing the main girder protruding portion 4 (male side joint).

[0024] Also, as an embodiment to which the segment joint of the present invention is applied, FIG. 5 shows a partial perspective view of segment 1. The main girder protruding portion 4 and the main girder notch portion 5 are fitted from the tunnel axis direction, and the shape is a dovetail groove shape that prevents slipping out in the tunnel circumferential direction. In the figure, reference numeral 2 indicates the joint plate of segment 1, reference numeral 3 indicates the main girder, reference numeral 6 indicates the vertical rib, and reference numeral 7 indicates the skin plate.

[0025] The segment joint of the present invention is composed of the main girder notch portion 5 having a female side shape shown in FIG. 1(b) and the main girder protruding portion 4 having a male side shape shown in FIG. 1(c), and has a trapezoidal dovetail groove shape. Tapered portions 4a and 5a are provided on the side surfaces of the main girder protruding portion 4 and the main girder notch portion 5, respectively, which have a function of guiding when the main girder protruding portion 4 is fitted into the main girder notch portion 5, are easy to slide, and facilitate the connection work.

[0026] Also, when the main girder protruding portion 4 is fitted into the main girder notch portion 5, a gap 8 as shown in FIG. 1(a) is formed. By providing this gap, the opening between the end straight portions on the main girder notch portion 5 side and the main girder protruding portion 4 side that has conventionally occurred is prevented from occurring.

[0027] Figure 2 shows the fitting procedure in the embodiment of Figure 1. Figure 2(a) shows the state before fitting, and there are gaps in the end straight portions on the side of the main girder notch portion 5 and the side of the main girder protruding portion 4. When attempting to fit as shown in Figure 2(b), the fitting portion slides due to the tapered portions 4a and 5a provided on the side surfaces of the main girder protruding portion 4 and the main girder notch portion 5.

[0028] As can be seen from the cross-sectional view of the main girder protruding portion 4 and the main girder notch portion 5 shown in Figure 2(c), the segment joint of the present invention has a dovetail groove shape with a trapezoidal cross-section due to the provision of the tapered portions 4a and 5a, so that the effect of easy fitting is obtained. Figure 2(d) shows the state after fitting of the main girder protruding portion 4 and the main girder notch portion 5. When the main girder protruding portion 4 and the main girder notch portion 5 are fitted, a gap is formed at the tip of the main girder protruding portion 4. This gap does not have to be filled, but it may be filled with a material that does not cause problems in terms of strength and durability, such as sealing, after fitting.

[0029] Figure 3 shows an enlarged view of the case where a reinforcing plate 5b is provided in the segment joint of the present invention. (a) is a perspective view of the entire fitting portion, (b) is a cut-away cross-sectional view of (a), (c) is a cross-sectional view seen from C in (a), and (d) is a cross-sectional view seen from D in (a).

[0030] A reinforcing plate 5b having approximately the same thickness as the main girder 3 is attached by welding or the like inside the notch portion formed in the main girder notch portion 5 so that the main girder protruding portion 4 of the other segment 1 connected to each other can be inserted.

[0031] The protruding portion of the main girder protruding portion 4 is processed in terms of plate thickness so that the plate thickness is thinner than the notch portion of the main girder notch portion. This is because when the main girder protruding portion 4 and the main girder notch portion 5 are fitted, the main girder protruding portion 4 may float up slightly and a step may occur. Therefore, the plate thickness is processed so that no step occurs. As shown in Figure 3(c), it is preferable that the surfaces of the main girder protruding portion 4 and the main girder notch portion 5 are flush.

[0032] FIG. 4 is an enlarged view showing the case where a reinforcing plate 5b is provided for the segment joint of the present invention, similar to FIG. 3. (a) is a perspective view showing the entire fitting portion, (b) is a cut-away sectional view of (a), (c) is a sectional view seen from E of (a), and (d) is a sectional view seen from F of (a).

[0033] In the main girder notch portion 5, a reinforcing plate 5b having the same thickness as the main girder 3 is attached by welding or the like inside the notch portion formed so that the main girder protruding portion 4 of the other segment 1 connected to each other can be fitted in.

[0034] In FIG. 3, the protruding portion of the main girder protruding portion 4 was thinned by performing plate thickness processing, but in FIG. 4, the plate thickness of the reinforcing plate 5b provided inside the notch portion of the main girder notch portion 5 was processed, and the portion where the protruding portion of the main girder protruding portion 4 fits was thinned.

[0035] As can be seen from the sectional view of FIG. 4(d), the reinforcing plate 5b inside the notch portion of the main girder notch portion 5 is formed in a shape with a recess so that the main girder protruding portion 4 fits, and the surfaces of the main girder protruding portion 4 and the main girder notch portion 5 are flush.

[0036] FIG. 6 shows an example in the case where trapezoidal ant grooveshaped main girder protruding portions 4 having smooth curved portions similar to those in FIG. 5 are provided in two stages. By providing the main girder protruding portions 4 in two stages, the stability in terms of maintaining the shape of the joint portion is enhanced. As shown in FIG. 6, a plurality of fitting portions of the segment joint of the present invention may be provided in multiple stages.

Explanation of Reference Numerals

[0037] 1... Segment 2... Joint plate 2a... Seal groove 2b... Seal groove 3... Main girder 3a... Seal groove 3b... Seal groove 4... Main girder protruding portion 4a... Taper portion 5... Main girder notch portion 5a... Taper portion 5b... Reinforcing plate 6... Vertical rib 7…Skin plate 8…Gap

Claims

1. In a segment joint of a steel segment for connecting steel segments each having a pair of main girders extending in the tunnel circumferential direction, a pair of joint plates extending in the tunnel axial direction and connecting between the main girders, and a skin plate provided on the tunnel rock side, a main girder protruding portion protruding outward in the circumferential direction from the joint plate is provided at an end portion of the main girder of one segment to be connected to each other, and a main girder notch portion into which the main girder protruding portion fits is provided at an end portion of the main girder of the other segment. The main girder protruding portion and the main girder notch portion are fitted from the tunnel axial direction and have a trapezoidal ant groove shape that prevents escape in the tunnel circumferential direction, and a taper is provided on a fitting surface where the main girder protruding portion and the main girder notch portion contact. A segment joint of a steel segment, characterized in that.

2. In the segment joint of the steel segment according to Claim 1, the width of the main girder notch portion in the main girder longitudinal direction is larger than the width of the main girder protruding portion in the main girder longitudinal direction, and a gap is formed between the rear end portion of the main girder notch portion in the main girder longitudinal direction and the front end portion of the main girder protruding portion in the fitting state of the main girder protruding portion and the main girder notch portion. A segment joint of a steel segment, characterized in that.

3. In the segment joint of the steel segment according to Claim 1 or 2, the main girder notch portion is formed at the end portion of the main girder, and a supplementary stiffening plate is provided on the segment inner surface side of the main girder notch portion. A segment joint of a steel segment, characterized in that.

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