JPH0816341B2 - Flexible material relief cross-section structure - Google Patents

Description

FIELD OF THE INVENTION The present invention relates to an undulating cross-section structure made of a flexible material, which is reinforced with woven fibers and has a bending line intersecting with the undulation.

Conventional art Various culverts such as sewers and common ditches are generally formed by box culverts (concrete rectangular boxes). The displacement force of unequal subsidence due to crustal movement tends to act on the box culvert buried in the ground. Therefore, if the box culverts that are successively and adjacently arranged are rigidly connected to each other, the box culvert body or the connection portion is broken when a large displacement force is applied, resulting in water leakage. For this problem, rubber between adjacent box culverts,
The joints made of a flexible material such as soft resin are used for connection to deal with uneven settlement.

FIG. 8 shows a box culvert 01 as an example. The box culvert 01 is buried in the ground and sequentially connected with a flexible joint 02 in the manner shown in FIG. Box culvert by two-dot chain line in the figure
It shows a state of unequal settlement of 01.

The flexible joint 02 is formed as a bellows-like structure (undulation cross-section structure) having one or more peaks as shown in FIGS. 10 and 11 so as to allow a large displacement of the box culvert. ing. Further, since the box culvert 01 is applied to a relatively shallow place in the ground and the earth pressure and water pressure acting on the flexible joint 02 are relatively small, the flexible joint 02 is provided with a reinforcing material (buried reinforcing material). Often made of pure flexible material not used.

Due to the high flexibility of the flexible joint 02 that does not use such a reinforcing material, it is possible to press it into the corners of the box culvert 01 and fit it relatively easily (No. 12).
Figure).

The problem to be solved by the invention is that a flexible joint that does not use a reinforcing material is thickened to obtain sufficient strength, and a large weight hinders workability. Occurs,
It has the drawback of being vulnerable to cuts.

This drawback is overcome by reinforcing the bellows of the flexible joint with woven fibers. However, since the reinforced flexible joint has a high rigidity, it is difficult to flex-fit the corner portion of the box culvert, and if it is forcibly bent, the bellows crest 03 falls in a wrinkle shape. There is a risk of abnormal deformation (Fig. 13) and loss of durability and sealability.

Therefore, it is conceivable to preliminarily mold the flexible joint containing reinforcing fibers into a shape that fits the corners of the box culvert, but since it becomes a complicated shape, in the conventional simple press molding method, It is difficult to obtain the desired structure because the reinforcing fibers are wrinkled or misaligned (Fig. 14:
In the figure, 04 indicates a wrinkle that has occurred). Further, if the local portion of the reinforcing fiber is cut or the local portion is removed in order to avoid the generation of wrinkles, the desired strength cannot be obtained.

Means and Actions for Solving the Problems The present invention was created under such technical background, and is an undulating cross-section structure made of a flexible material having a bending line intersecting with the undulation, It is an object of the present invention to provide an undulating cross-section structure which has a desired strength without wrinkles or extra "looseness" in the produced reinforcing fiber.

The purpose is to reinforce the flexible material, which is the base layer, with woven fibers that have been given a three-dimensional shape in advance by sewing a three-dimensionally cut product at a position corresponding to the bending line of the product. Achieved by

EXAMPLE An example of the present invention shown in FIGS. 1 to 7 will be described below.

FIG. 1 shows a bend 2 of a joint 1 made of a flexible material. The joint 1 is reinforced over its entire surface with the woven fibers 3 and is formed as an undulating cross-section structure having peaks 4, 4, and valleys 5. The bending line 6 of the joint 1 is A in the figure.
It is a tangent line in which the half part and the B half part are continuous in an intersecting manner. The A half and the B half intersect with each other at an angle θ, and the bending line 6 passes through both ends C, C and has an inclination angle α with respect to the A half and the B half.
(However, α = 90 ° −θ / 2). Note that the angle 2α matches the corner angle of the box culvert.

Prior to being embedded, the woven fiber 3 embedded in the flexible material which is the base layer of the joint 1 is sewn at the position corresponding to the bending line so as to have the shape shown in FIG. 1 by itself. ing.

 Here, a method of sewing the woven fiber 3 will be described.

First, it is necessary to obtain a half body of the woven fiber 3 corresponding to the A half portion and the B half portion as a development view. This development view is obtained by obtaining a locus of a cut 8 obtained by cutting a straight piece 7 having an undulating cross-section that matches the A half part and the B half part along a plane S intersecting at an inclination angle α ( (Fig. 2).

That is, the length of a perpendicular line drawn from a point E on the cut edge 8 to the reference plane F is h, and from the foot G of the perpendicular line to both ends D, D of the cut edge 8.
Let e be the length of a perpendicular line that includes a line segment (which is on the plane S) that connects the lines and that intersects the reference plane F at a right angle. (Fig. 4, Fig. 4).

From the relationship between the length (e) obtained by the equation (1) and the length (W) between the points D and E along the cut 8, the development view shown in FIG. 5 is obtained. Cutting the woven fiber as shown in this development is called three-dimensional cutting. In the figure, m is the seam allowance of the woven fiber, and two woven fibers 7A and 7A having the same shape are sewn as shown in FIG. 6 except for the seam allowance (m), and as shown in FIG. By folding back, the sewn woven fiber 3 having the same three-dimensional shape as the bent portion 2 of the joint 1 can be obtained.

When the shape of the cut 8 is displayed as a mathematical expression, the function h (W) can be obtained by numerical calculation. However, when the mathematical expression cannot be displayed, the length (h) can be obtained from the drawing. . By obtaining the length (h), the length (e) can be obtained from the equation (1).

Also, note that when sewing, the sewing strength varies depending on the material of the sewing thread and the material of the woven fiber, and the appropriate seam allowance (m) is 3 to 15 mm. However, if it is too large, it will be uneconomical, and it will cause wrinkles, and unwoven rubber is attached to the woven fiber in advance. In this case, inconvenient stickiness is likely to occur during sewing, and in order to avoid this stickiness, it is effective to dust with zinc stearate powder or the like.

Test Example A plain weave nylon canvas was used as a reinforcing woven fiber. The strength of the canvas is 100 kg / cm in the warp direction and 30 kg / cm in the weft direction. In the material removal, the warp direction was aligned with the length (W) direction in FIG.

A developed view of the canvas 7A (Fig. 5) was obtained by the above-described method shown in Figs. 2 to 4, and was cut with a seam allowance (m) of about 10 mm.

Two pieces of canvas 7A, 7A were sewn in a straight line in the manner shown in FIG. 6 using a nylon thread having a strength of 30 kg / piece and a pitch of 3 mm.

In addition, the sewing thread pitch is set to 3 mm because the safety factor is taken into consideration, the strength of the sewing thread is 50% of 30 kg / thread (30 × 0.5 kg /
Book) and the strength after sewing with this value (depending on the sewing thread)
Is the result of aiming to be equal to or higher than the canvas strength (strength in the weft direction = 30 kg / cm).

Using the sewn canvas as a reinforcing material, the substrate rubber material was integrally molded to obtain a rubber joint 1. The joint 1 is a quadrangular tubular body (quadrangular annular body) of 600 × 600 mm that fits a box culvert having a square cross section, a part of which is shown in FIG.

When the obtained joint 1 was mounted on an actual box culvert, it was possible to mount it as designed without any difficulty. Then, a pressure resistance test was performed. The design strength of the joint 1 is 150 mm in shear displacement (external pressure 1.5 Kgf / cm ² ), but in the test, it was confirmed that it exceeds 150 mm in shear displacement (external pressure 3 Kgf / cm ² ).

EFFECTS OF THE INVENTION As is clear from the above description, an undulating cross-section structure made of a flexible material, which is reinforced with woven fibers and has a bending line intersecting with the undulation, is obtained by three-dimensionally cutting A structure has been proposed in which a flexible material that is a base layer is reinforced with woven fibers that have been given a three-dimensional shape in advance by sewing at positions corresponding to lines.

The undulating cross-section structure made of a flexible material of the present invention has a three-dimensional shape given to the reinforcing woven fiber in advance, so that the flexible material can be easily integrally molded. Not only does it have the necessary strength, it does not cause creep, it does not break due to cuts, and it is lightweight because the thickness of the flexible substrate material layer can be made small. It has various features such as a shape that fits the part.

[Brief description of drawings]

FIG. 1 is a perspective view of a main part of a rubber joint for box culverts according to an embodiment of the present invention, and FIGS. 2 to 4 are views for developing a developed view of a woven fiber which is a reinforcing material for the joint. Drawing, FIG. 5 is the developed view, FIG. 6 is a view showing a state in which the two woven fibers obtained according to the developed view are sewn, and FIG. 7 is the woven fiber after sewing being inverted and expanded. FIG. 8 is a diagram showing a state in which the box culvert is shown as an example, and FIG. 9 is a diagram showing a state in which the box culvert is connected by a flexible material joint and buried in the ground. 10 and 11 are cross-sectional views of the joint, respectively, and FIG. 12 is a view showing the fitting state of the joint at the corner of the box culvert, 13
FIG. 14 and FIG. 14 are views showing a bent portion of a conventional flexible material joint, respectively. 1 ... Joint, 2 ... Bending part, 3 ... Woven fiber, 4 ... Mountain part, 5 ...
Valley, 6 ... bent line, 7 ... piece, 8 ... cut.

Claims (1)

[Claims] 1. An undulating cross-section structure made of a flexible material, which is reinforced with woven fibers and has a bending line that intersects the undulations, wherein the woven fibers are three-dimensionally cut and correspond to product bending line positions. The undulating cross-section structure made of a flexible material, which has been given a three-dimensional shape by itself by being sewn in.