Prestressed structures and methods for connecting prestressed structures

Abstract

The present invention provides a connected prestressed structure that can be used to create a long prestressed structure with the necessary prestress introduced. [Solution] The prestressed structure 1A comprises a longitudinally extending wooden member 2 having a through hole 2a penetrating in the longitudinal direction Lo, a longitudinally extending tension member 3 that passes through the through hole and whose ends 3b1 and 3b2 are exposed from the through hole, a longitudinally extending reinforcing pipe 4 provided between the inner surface of the through hole and the circumferential surface of the tension member in the short direction SH, a pair of contact plates 5 through which the exposed tension member passes and which abut the longitudinal end faces 2b1 and 2b2 of the wooden member and the longitudinal end faces 4b1 and 4b2 of the reinforcing pipe, respectively, and a pair of nuts 6 that are fitted from the longitudinal end faces 3b11 and 3b22 of the exposed tension member and fix the tension member to the pair of contact plates, thereby introducing prestress in a direction in which the longitudinal end faces of the wooden member are pressed against each other by one of the contact plates.

Description

TECHNICAL FIELD

[0001] The present invention relates to a prestressed structure and a method for connecting prestressed structures.

BACKGROUND ART

[0002] A prestressed structure using a wooden member is disclosed, the prestressed structure comprising a joined wooden member that is joined to a member to be joined with its longitudinal end face abutted thereagainst, the joined wooden member having an insertion hole penetrating in the longitudinal direction, and prestress being introduced in the direction in which the joining end face of the joined wooden member and the longitudinal end face of the joined wooden member are pressed against each other by a tension member that is passed through the insertion hole and penetrates the member to be joined, whereby the joined wooden member is joined to the member to be joined, wherein the joined wooden member includes a reinforcing pipe member fitted inside the insertion hole, an end portion of the reinforcing pipe member is exposed at the longitudinal end portion of the joined wooden member, and the end portion of the reinforcing pipe member is brought into contact with the member to be joined (see Patent Document 1).

PRIOR ART DOCUMENTS

PATENT DOCUMENTS

[0003]

PATENT DOCUMENT 1

SUMMARY OF THE INVENTION

PROBLEM TO BE SOLVED BY THE INVENTION

[0004] However, the invention described in Patent Document 1 has a limit in obtaining a long prestressed structure into which necessary prestress has been introduced. The present invention has been made in view of such circumstances, and an object thereof is to provide a prestressed structure and a method for connecting prestressed structures, which are capable of obtaining a long prestressed structure into which necessary prestress has been introduced.

MEANS FOR SOLVING THE PROBLEM

[0005] The prestressed structure and the method for connecting prestressed structures according to the present invention are as follows. (1) A prestressed structure comprising: a longitudinally extending wooden member having a through hole that penetrates in the longitudinal direction; a longitudinally extending tension member that passes through the through hole and whose ends are exposed from the through hole; a longitudinally extending reinforcing pipe provided between the inner surface of the through hole and the short-side circumferential surface of the tension member; a pair of contact plates through which the exposed tension member passes and which abut against the longitudinal end faces of the wooden member and the longitudinal end faces of the reinforcing pipe, respectively; and a pair of nuts fitted from the longitudinal end faces of the exposed tension member and which fix the tension member to the pair of contact plates, wherein the pair of contact plates introduces prestress in a direction in which the longitudinal end faces of the wooden member are pressed against each other. (2) A method for connecting prestressed structures, comprising: preparing a plurality of prestressed structures as described in (1); connecting one end of each of the exposed tension members in a straight line with a coupler; placing a maintenance member to maintain the introduced prestress between the contact plates of each of the opposing prestressed structures when connected; and releasing one of the pair of nuts of each of the plurality of prestressed structures. [Effects of the Invention]

[0006] The present invention provides a prestressed structure and a method for connecting prestressed structures, which can be obtained as long prestressed structures with the necessary prestress introduced. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a conceptual diagram of the external appearance of a prestressed structure according to this embodiment, where (a) is a conceptual side view, (b) is a conceptual view of one end face of the prestressed structure as seen from the top direction of the paper (direction A) of (a), (c) is a conceptual view of the other end face of the prestressed structure as seen from the bottom direction of the paper (direction B) of (a), and (d) is a conceptual cross-sectional view when (a) is cut along line CC. [Figure 2]Figure 2 is a conceptual cross-sectional view showing a prestressed structure when cut along the DD line in Figures 1(a), (b), and (c). [Figure 3] Figure 3 is an exploded perspective conceptual diagram showing each component of the prestressed structure according to this embodiment, as shown in Figures 1 and 2. [Figure 4] Figure 4 is an external conceptual diagram showing a connected (extended) prestressed structure according to this embodiment, where (a) is a vertical conceptual diagram showing a connected prestressed structure 100 in which at least one of the exposed ends 3b1 and 3b2 of the prestressed structure 1A shown in Figure 1 is connected in series by a coupler 10 and a maintenance member 200, (b) is an enlarged side vertical conceptual diagram of the vicinity of the coupler 10 of the connected prestressed structure 100 (maintenance member 200 omitted) as seen from the right direction (E direction) of the paper in (a), (c) is a cross-sectional conceptual diagram when cut along the FF line in (b), (d) is a cross-sectional conceptual diagram when cut along the FF line in (b) with both ends 3b1 and 3b2 of the tension member 3 omitted from (c), and (e) is an enlarged perspective conceptual diagram of the maintenance member 200. [Modes for carrying out the invention]

[0008] A connected prestressed structure according to one embodiment of the present invention will be described with reference to Figures 1 to 4. Note that reference numerals may be omitted if they are the same in all figures. The prestressed structure 1A according to this embodiment will be described in detail. The prestressed structure 1A comprises a wooden member 2 extending in the longitudinal direction Lo and having a through hole 2a penetrating in the longitudinal direction Lo; a tension member 3 extending in the longitudinal direction Lo and passing through the through hole 2a, with both ends 3b1 and 3b2 exposed from the through hole 2a; a reinforcing pipe 4 extending in the longitudinal direction Lo and provided between the inner surface of the through hole 2a and the circumferential surface of the tension member 3 in the short direction SH; and the exposed tension member 3, each passing through both end faces 2b1 in the longitudinal direction Lo of the wooden member 2. The structure comprises a pair of contact plates 5, 5 that abut against the end faces 4b1, 4b2 of the reinforcing pipe 4 in the longitudinal direction Lo, respectively, and a pair of nuts 6, 6 that are fitted to the end faces 3b11, 3b22 of the exposed tensioning member 3 in the longitudinal direction Lo, respectively, and fix the tensioning member 3 to the pair of contact plates 5, 5, and the structure has a form in which prestress is introduced in a direction in which the end faces 2b1, 2b2 of the wooden member 2 in the longitudinal direction are pressed against each other by one of the contact plates 5 and the other contact plate 5.

[0009] Specifically, the prestressed structure 1A according to this embodiment comprises a wooden member 2, a tensioning member 3, a reinforcing pipe 4, a pair of contact plates 5, 5, and a pair of nuts 6, 6. The wooden member 2 has a through hole 2a that penetrates in the longitudinal direction Lo. The wooden member 2 is made of solid wood or laminated wood, has a longer side in the longitudinal direction Lo, a shorter side in the transverse direction SH, and extends in the longitudinal direction Lo. For example, the wooden member 2 has a through hole 2a with a diameter T1 that penetrates in a straight line toward the longitudinal direction Lo in the center of both end faces 2b1 and 2b2, and both end faces 2b1 and 2b2 are, for example, square (the length of one side L is L1) and are composed of a prism shape with a width of L2 in the longitudinal direction Lo.

[0010] The tensioning member 3 is passed through the through hole 2a, and both ends 3b1 and 3b2 of the tensioning member 3 are exposed from the through hole 2a and extend in the longitudinal direction Lo. The tensioning member 3 has threaded portions 3a, 3a on the circumferential surfaces in the short direction SH of both ends 3b1 and 3b2. The tensioning member 3 is, for example, a steel bar (e.g., a PC steel bar) having an outer diameter T3 smaller than the inner diameter T2 of the reinforcing pipe 4 described later, and whose width L4 in the longitudinal direction Lo is longer than the width L2 of the wood member 2 in the longitudinal direction Lo and the width L3 of the reinforcing pipe 4 described later.

[0011] The reinforcing pipe 4 is provided between the inner surface of the through hole 2a and the circumferential surface of the tensioning member 3 in the short direction SH, and extends in the longitudinal direction Lo. The reinforcing pipe 4 is made of, for example, steel and has a cylindrical shape that penetrates in the longitudinal direction Lo. The inner diameter T2 and outer diameter T4 of the cylindrical shape are determined by considering the characteristics of the tensioning member 3 provided on the inner surface and the stress of the introduced prestress.

[0012] The reinforcing pipe 4 has, for example, an inner diameter T2 that is larger than the outer diameter T3 of the tensioning member 3, an outer diameter T4 that is approximately the same as the inner diameter T1 of the through hole 2a of the wooden member 2, and a longitudinal width L3 that is approximately the same as the longitudinal width L2 of the wooden member 2. A grout material is filled between the inner surface of the reinforcing pipe 4 and the circumferential surface of the tensioning member 3 in the short direction SH to prevent rusting of the tensioning member 3.

[0013] The pair of contact plates 5, 5 are each passed through by the tensioning member 3 exposed from the through hole 2a, and they abut against the end faces 2b1, 2b2 of the wooden member 2 in the longitudinal direction Lo and the end faces 4b1, 4b2 of the reinforcing pipe 4 in the longitudinal direction Lo, respectively.

[0014] The pair of abutment plates 5, 5 are made of, for example, steel material, the surfaces that respectively abut against both end faces 2b1, 2b2 in the longitudinal direction Lo of the wood member 2 have substantially the same shape as both end faces 2b1, 2b2 of the wood member 2, for example, a square (with one side L having a length of L1), and have a rectangular plate shape with a width of L5 in the longitudinal direction Lo, and through-holes 5a, 5a having an inner diameter T5 substantially equal to the outer diameter T3 of the tension member 3 for allowing the tension member 3 to pass through are provided in the central portion. That is, the tension member 3 is passed through the through-hole 2a of the wood member 2, also passed through the through-holes 5a, 5a of the pair of abutment plates 5, 5, and the tension member 3 is fixed to the pair of abutment plates 5, 5 by a pair of nuts 6, 6 to be described later, so that both end portions 3b1, 3b2 having a length of approximately half the length obtained by subtracting the total value of the width L2 in the longitudinal direction Lo of the wood member 2 (substantially the same width L3 in the longitudinal direction Lo of the reinforcing pipe 4), the width (L5×2) in the longitudinal direction Lo of the pair of abutment plates 5, 5, and the width (L6×2) in the longitudinal direction Lo of the pair of nuts 6, 6 to be described later from the width L4 in the longitudinal direction Lo of the tension member 3 are exposed from the pair of nuts 6, 6 respectively.

[0015] The pair of nuts 6, 6 are respectively fitted from both end faces 3b11, 3b22 at the outermost peripheral edges of both end portions 3b1, 3b2 in the longitudinal direction Lo of the tension member 3 exposed from the through-hole 2a, the through-hole 5a and the nuts 6, and fix the tension member 3 to the pair of abutment plates 5, 5. The inner diameter T6 of the pair of nuts 6, 6 is substantially the same as the outer diameter T3 of the tension member 3.

[0016] Since the prestressed structure 1A according to the present embodiment has the above-described configuration, both end portions 3b1, 3b2 of the exposed tension member 3 can be connected to the coupler 10. Therefore, the prestressed structure 1A according to the present embodiment can obtain a long prestressed structure into which a required prestress is introduced.

[0017] An example of the method for introducing the above-described prestress will be described. The reinforcing pipe member 4 is disposed in the through-hole 2a of the wooden member 2, the tendon 3 is disposed on the inner surface of the reinforcing pipe member 4, grout material is filled between the inner surface of the reinforcing pipe member 4 and the outer surface of the tendon 3, and after a pair of abutment plates 5, 5 are attached, before the tendon 3 is fixed by the pair of abutment plates 5, 5 using a pair of nuts 6, 6, both end portions 3b1, 3b2 of the tendon 3 exposed from the through-hole 2a and the through-hole 5a are tensioned by pulling each other in the longitudinal direction Lo away from the wooden member 2, and a pair of nuts 6, 6 are respectively screwed from both end faces 3b11, 3b22 to fix the tendon 3 to the pair of abutment plates 5, 5, and then the tensile tension is released. Thereby, prestress is introduced in the direction in which both end faces 2b1, 2b2 of the wooden member 2 and both end faces 4b1, 4b2 of the reinforcing pipe member 4 are pressed against each other by the pair of abutment plates 5, 5. Thereby, the wooden member 2 receives a force in the compression direction from the pair of abutment plates 5, 5, and is sandwiched between the pair of abutment plates 5, 5 so that the force in the compression direction acts thereon. Similarly, the reinforcing pipe member 4 also receives a force in the compression direction.

[0018] In the method for connecting prestressed structures according to the present embodiment, a plurality of the prestressed structures 1A are prepared, one end portions 3b2, 3b1 of each of the exposed tendons 3 are connected in a straight line by a coupler 10, a maintenance member 200 for maintaining the introduced prestress is disposed between the abutment plates 5, 5 of the respective opposing prestressed structures 1A, 1A at the time of connection, and one of the pair of nuts 6, 6 of each of the plurality of prestressed structures 1A, 1A is released.

[0019] Thereby, it is possible to obtain a connected prestressed structure 100 in which prestress is introduced in the direction of being pressed against each other over the entirety by the abutment plate 6 at one outermost end and the abutment plate 6 at the other outermost end.

[0020] The coupler 10 is made of a rectangular steel material and has through holes 10a that hold one end 3b2, 3b1 of the tension members 3 together. Specifically, the outer surfaces of the exposed ends 3b2, 3b1 of the tension members 3 in each of the multiple prestressed structures 1A, 1A have male threads, and the inner surface of the through hole 10a of the coupler 10 has female threads that screw into the male threads.

[0021] The maintenance member 200 has the exposed ends 3b1, 3b2 of the tensioning member, the coupler 10 and the nuts 6, 6 positioned on the inside, and also has an opening 200K that releases the nuts 6 of at least one of the multiple adjacent prestressed structures 1A, 1A in the connecting prestressed structure 100.

[0022] The maintenance member 200 is composed of, for example, four rectangular steel members 200a, 200b, 200c, and 200d, and can be placed at the four corners forming a 90° angle when the faces of the opposing contact plates 6 between multiple prestressed structures 1A, 1A are square. [Explanation of Symbols]

[0023] 1A Prestressed structure 2. Wooden members 2a Through hole 2b1, 2b2 end faces 3 Tensors 4 Reinforcement pipe material 5.5 Pair of contact plates 6, 6 pairs of nuts 100 Linked prestressed structures Lo Longitudinal direction SH Short direction

Claims

1. A woody member extending in the longitudinal direction having a through hole that penetrates in the longitudinal direction, A tensioning member extending in the longitudinal direction, which is passed through the through hole and whose ends are exposed from the through hole, A reinforcing pipe is provided between the inner surface of the through hole and the circumferential surface of the tensioning member in the short direction, and extends in the longitudinal direction. The exposed tensioning members each pass through a pair of contact plates that abut against both ends of the wooden member in the longitudinal direction and both ends of the reinforcing pipe in the longitudinal direction, The exposed tensioning member is fitted to both longitudinal ends of the tensioning member, and comprises a pair of nuts that secure the tensioning member to the pair of contact plates, A prestressed structure in which prestress is introduced in a direction such that the longitudinal end faces of the wooden member are pressed against each other by the pair of contact plates.

2. A method for connecting prestressed structures, comprising: preparing a plurality of prestressed structures as described in claim 1; connecting one end of each of the exposed tension members in a straight line with a coupler; arranging a maintenance member to maintain the introduced prestress between the contact plates of each of the opposing prestressed structures when connected; and releasing one of the pair of nuts of each of the plurality of prestressed structures.

Images