JPH0649801A - Manufacturing method of sleeper provided with elastic body - Google Patents

Abstract

PURPOSE:To enable a sleeper provided with an elastic body to be manufactured simply by placing concrete from the top surface of a concrete frame after arranging reinforcements in the frame, pressing an elastic member on the top surface of the concrete before the concrete is hardened and causing the concrete to be hardened by covering the top surface of the concrete with a lid type frame. CONSTITUTION:Concrete 5 is placed after arranging reinforcements or PC steel material in a frame on the top surface of a frame 4. Before the concrete 5 placed in the frame 4 hardens, an elastic member 2 is pressed on the concrete 5 surface with its side provided with resistance protrusions 6 facing the concrete 5 surface. A lid type frame is then fixed on the top surface of the elastic member 5. After the concrete 5 is hardened, it is removed from the frame 4 and a sleeper provided with the elastic member 2 on its bottom surface is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a sleeper having an elastic body, which is used for a ballast track.

[0002]

2. Description of the Related Art An elastic sleeper consisting of a main body of concrete and an elastic portion covering the bottom of the concrete is widely used because it has excellent vibration absorbing ability and reduces maintenance due to abrasion of ballast. . The conventional manufacturing method is, for example, as shown in JP-B-55-48968 (FIG. 8), in which concrete b is placed in a form a, and before the concrete is still hardened, an elastic member c is pressed against the upper surface of the concrete to form an integral body. The method of molding into is proposed. Alternatively, as shown in FIG. 9, a method has also been proposed in which an elastic member c is erected vertically inside a mold a whose upper part is open, and concrete b is placed on the side surface of the elastic member c.

[0003]

[Problems to be Solved by the Invention] In the production of the conventional elastic sleeper as shown in FIG. 8, there are the following problems. <A> Regarding the adhesion between the elastic member and the concrete, the only idea was to engrave a groove on the contact surface of the elastic member with the concrete. Therefore, the adhesion between the elastic member and the concrete cannot be said to be perfect, and high reliability cannot be obtained especially for sleepers used for severe use. <B> When the elastic member is pressed against the concrete surface, the phenomenon that water or air on the concrete surface intervenes between them is unavoidable. For this reason, there is a drawback that the adhesion efficiency between the two is further reduced. On the other hand, the manufacturing method as shown in FIG. 9 has the following problems. <a> Generally, the sleepers are not simple rectangular parallelepipeds, and there are irregularities for fastening the rails on the upper part, and the side surfaces are formed by curved surfaces. However, it is extremely difficult to manufacture sleepers having such a complicated shape by the method of manufacturing with the form a having the upper surface opened as shown in FIG. <B> When sleepers other than a simple rectangular parallelepiped are actually manufactured by the manufacturing method of FIG. 9, an extremely complicated shape frame that can be disassembled by dividing into a large number is required. Therefore, there are many problems in using it for actual production.

[0004]

SUMMARY OF THE INVENTION The present invention has been made in order to improve the above points, and can easily and inexpensively manufacture an elastic sleeper having a complicated shape in which elastic members are integrally combined. It is an object of the present invention to provide a method for producing an elastic sleeper that can be manufactured. A further object of the present invention is to provide a method for manufacturing an elastic sleeper, which has a large peeling resistance between the concrete body and the elastic member.

[0005]

[Means for Solving the Problems] That is, according to the present invention, in the production of an elastic sleeper composed of a main body portion of concrete and an elastic portion covering the bottom surface thereof, a shape corresponding to the upper surface of the sleeper is formed on the bottom surface, For the surface corresponding to the bottom of the sleeper, use a mold with an open shape at the top, place reinforcing bars or PC steel in this mold, and then place concrete to increase the peel resistance before the concrete hardens. This is a method for manufacturing sleepers with elastic bodies, in which an elastic member having a plurality of projections of the shape described above is pressed against the upper surface of concrete, the formwork is fixed from the upper portion, and the concrete is hardened.

[0006]

The present invention will be described below with reference to the drawings. <B> Target sleeper (FIG. 1) The sleeper targeted by the manufacturing method of the present invention is an elastic sleeper including a main body portion 1 of concrete and an elastic member 2 covering the bottom surface thereof. The shape can be used as a rectangular shape, but in order to increase the resistance (shear resistance) to the load acting in the direction orthogonal to the running direction of the train when installed on the track, the shape of protruding legs on both sides It can also be used for sleepers. Sleepers with such legs protruding generally have irregularities formed on the rail fixing surface,
It is relatively difficult to manufacture the sleeper by the above-mentioned conventional method because the shape is complicated, for example, the front surface and the back surface of the sleeper are curved or inclined. Although such a shape is a general elastic sleeper, a sleeper having a more complicated shape can be manufactured.

<B> Form of Form (FIG. 2) A form 4 having a shape corresponding to the shape of a sleeper is prepared. The form 4 has a bottom surface having a shape corresponding to the upper surface of the sleeper. Then, the surface corresponding to the bottom of the sleeper is opened to the upper part. That is, the formwork 4 has a shape in which the upper surface and the bottom surface of the sleeper are turned upside down, and a portion corresponding to the bottom surface of the formwork 4 is open.

<C> Manufacture of Elastic Member 2 (FIG. 3) In parallel with the above steps, the elastic member 2 of the elastic sleeper is manufactured. The elastic member 2 is a plate body made of an elastic material and attached to the bottom surface of the sleeper, and is made of, for example, rubber or urethane elastomer. Resistance projections 6 are formed at a plurality of locations on one surface of the plate of the elastic member 2. In addition, in order to improve the surface strength inside the elastic member 2, a mesh material made of fibers may be embedded near the surface.

<D> Shape of Resistance Protrusion The resistance protrusion 6 described above is formed in a shape having a particularly large peeling resistance. As the shape having a large peeling resistance, the basic shape is a trapezoid having a reversely inclined side surface, that is, a shape in which the short side of the trapezoid is attached to the plane portion of the elastic member. Therefore, when the resistance protrusions 6 are press-fitted into the concrete which is not yet solidified in a later step, the dimensions increase as the resistance projections 6 move into the concrete. The inverted trapezoidal shape as described above can be widely used. However, in order to further increase the peeling resistance and ensure the adhesion between the elastic member and the concrete, the contact surface of the elastic member with the concrete and the side surface of the resistance projection 6 are separated. The angle (FIG. 5α) is preferably set within the following range. Maximum angle 84 degrees, minimum angle 45 degrees, preferably 80-60 degrees

<E> Grounds for selecting maximum and minimum angles The reasons and results for selecting the maximum and minimum angles as described above are as follows. [Maximum Angle] Generally, the larger the angle between the inverted trapezoidal side surface of the resistance projection 6 and the concrete contact surface of the elastic member, the easier the elastic member is to manufacture, and moreover, it is easy to penetrate into the inside of the concrete, and the circumference of the resistance projection is large. It is difficult for air voids to accumulate on the. However, after the concrete is hardened, the peeling resistance is small because the fitting portion of the elastic member to the concrete is small. [Minimum angle] On the other hand, the smaller the angle between the reverse trapezoidal side surface of the resistance projection 6 and the concrete contact surface of the elastic member is, the smaller the angle is, and the stronger the adhesive force with the concrete is, The peeling resistance increases. However, if the angle is set to a certain angle or less, it becomes difficult to manufacture the elastic member, and it becomes difficult for concrete to be filled around the resistance protrusion. Considering the manufacturing method of the elastic member as described above and the filling property of the concrete around the resistance protrusion, the maximum angle and the minimum angle should have certain limits. In order to know the limit, the following test was conducted.

<F> Test for Determining Maximum and Minimum Angle A test was conducted using the apparatus shown in FIG. That is, the inside of a wooden box is filled with concrete, and the elastic member 2 provided with the protruding projections is pressed from the upper surface thereof. as a result,
The resistance protrusion 6 is embedded in the concrete and hardened as it is. After 28 days have passed since the concrete was placed,
It is a method of peeling off using a hook on a steel plate attached to the upper surface of the elastic member, and the pulling force in that case is considered as peeling resistance and measured. Shape of resistance protrusion of elastic member Height of protrusion: 10 mm. Protrusion length: 50 mm. Trapezoidal short side: 15 mm. α: A plurality of types of elastic members having different angles were molded. Test results d Angle α Per protrusion One state of air void around the protrusion Adhesive strength in mm 0 90 degrees 0.5 to 1.0 kg There is no void. 184 degrees 5-8 There are no voids. 279 degrees 15-25 There are small voids. 6 59 degrees 45-55 Small voids are scattered. 10 45 degrees 45-55 Some voids remain. 1240 degrees 10-18 There is no concrete in the corners of the resistance projections, and there are large voids. Generally, adhesive strength of 5 kg or more is desirable. Further, it is not preferable that the air void around the protrusion is large. This is because water contained in a large void reduces the durability of repeated freezing and thawing, and the adhesion of the elastic member is rapidly reduced. As a result of the above comprehensive judgment, the above numerical values were selected.

<G> Section of Elastic Member The elastic member 2 is a long strip having the same size as the bottom surface of the sleeper. The surface exposed to the outside as its bottom surface is a precise plane, but the contact surface 8 contacting the concrete can be formed as a slope in the transverse direction. (FIG. 6) That is, the cross section is thickest at the center and gradually thinner from the center to the left and right. Therefore, in the manufacturing process described below, air and water on the concrete surface can be easily discharged along the slope of the contact surface 8, so that air voids are less likely to occur around the resistance protrusions, and good adhesion can be obtained. Further, a degassing hole 9 is provided in the vicinity of the resistance projection 6 protruding from the contact surface 8 of the elastic member 2 to the concrete.
May be penetrated. The degassing holes 9 are merely small-diameter holes, and water or air on the concrete surface that has not solidified yet can be discharged from the holes during manufacturing.

<H> Placing Concrete After arranging a reinforcing bar or PC steel material in the frame from the upper surface of the above-mentioned form 4, concrete 5 is poured. Since the upper surface of the mold 4 corresponding to the bottom of the sleeper is wide open, the concrete 5 can be easily placed.

<R> Pressing the elastic member 2 Before the concrete 5 cast in the mold 4 is hardened, the elastic member 2 is pressed from the upper surface of the concrete 5. In this case, the side of the elastic member 2 on which the resistance projection 6 is provided is pressed against the surface of the concrete 5. In addition, this pressing work is
When air is not pressed against the entire surface at one time but gradually pressed from one end, the air inside is removed, and sufficient adhesion between the elastic member 2 and the concrete 5 can be taken. Further, when the contact surface 8 is formed to have an outward inclination, the air and water inside can be pushed outward, and the air and water can be discharged from there through the deaeration holes 9, so that the elastic member 2 and Adhesion with concrete is sufficiently performed.

<N> Extraction of deaeration zone The deaeration zone 7 may be arranged in contact with the resistance projection of the elastic member. The deaeration zone 7 is formed of a simple long cloth, and is temporarily fixed to the concrete contact surface 8 of the elastic member at a position in contact with the resistance projection 6 as shown in FIG. One end of the deaeration zone 7 is exposed to the outside of the elastic member 2, and after the pressing work against concrete is completed, the exposed end is gently pulled out. Then this deaeration zone 7
The water and air on the concrete surface are entrained and guided to the outside in accordance with the movement of, and as a result, the side surface of the resistance projection is sufficiently filled with concrete, and sufficient adhesion between the concrete and the elastic member 2 can be expected. In this way, when the elastic member 2 is pressed against the entire surface of the concrete 5, the lid formwork is fixed from above. Concrete 5
Waiting for the curing of No. 2 and releasing from the mold 4 completes a sleeper whose peripheral surface is smoothly finished according to the mold.

[00016]

Since the present invention is as described above, the following effects can be obtained. <A> During manufacturing, all surfaces of the elastic sleeper other than the bottom surface are surrounded and protected by the mold 4. Therefore, the surface other than the bottom surface has an accurate shape, and the surface of the elastic sleeper having a high commercial value can be obtained. <B> The sleeper is manufactured with its top and bottom surfaces reversed. Therefore, the demolding work is simple and there is no need to employ a complicated split mold, and the manufacturing cost of the mold 4 can be kept low. <C> The adhesion between the elastic member attached to the bottom of the sleeper and the concrete is extremely large. Therefore, it can be used for a wide range of purposes as a sleeper used under severe conditions. <D> The shape of the resistance projections of the elastic member and the degree of filling of the concrete are incompatible with each other. However, in the present invention, the angle of the resistance projection is set by finding the point of compromise between the two, so that it is possible to obtain a sleeper having a large resistance against peeling of the elastic member and having a good filling property of concrete. <E> Since the manufacturing method is simple, it is possible to manufacture a concrete sleeper with an elastic member at low cost. <F> Since the elastic member and the concrete sleepers are highly adherent, the elastic member and the concrete may separate even when performing rigorous repeated movement and pushing work when setting the sleeper in the ballast. Absent. <G> Compared with the method of manufacturing sleepers in a sideways state, it is possible to freely manufacture sleepers having a wide range of shapes such as those having curved lines on the front and back surfaces and those having irregularities. <H> Since an elastic member exists between the concrete and the ballast, an excellent vibration damping effect can be obtained, and since the elastic member absorbs vibration, it is possible to prevent the rail from sinking due to wear of the ballast. . <R> When a degassing zone is used, gas and excess water are drawn to the outside as the zone is pulled out. As a result, the occurrence of voids can be greatly reduced. <N> If the elastic member is thickest in the center and gradually thinned in the periphery, air and water on the concrete surface can be easily discharged along the slope of the contact surface. As a result, the generation of air voids around the resistance protrusion can be reduced.

[Brief description of drawings]

FIG. 1 is an explanatory view of an example of an elastic sleeper.

FIG. 2 is an explanatory view of a mold.

FIG. 3 is an explanatory view of an elastic member.

FIG. 4 is an explanatory diagram of a manufacturing process of the present invention.

FIG. 5 is an explanatory diagram of how to use the deaeration zone.

FIG. 6 is a sectional view of an embodiment of an elastic member.

FIG. 7 is an explanatory diagram of a test method.

FIG. 8 is an explanatory view of an example of a conventional method for manufacturing an elastic sleeper.

FIG. 9 is an explanatory view of an example of another conventional method for manufacturing an elastic sleeper.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Naoto Mifune, Inoue Mitsumachi, 8-chome, Kokubunji city, Tokyo 38 38 Institute of Railway Technology, Incorporated (72) Inventor, Katsutoshi Ando, 8-chome, Hikarimachi, Kokubunji, Tokyo 38 Inside the Railway Technical Research Institute (72) Inventor Koichi Minegishi 497 Bada, Tama City, Tokyo (72) Inventor Osamu Otsubo 3-10 Nihonbashi Yokoyamacho, Chuo-ku, Tokyo Nisshin Spinning Co., Ltd. (72) Inventor Yoshihiko Ogawa 1-18-1 Nishiarai Sakaecho, Adachi-ku, Tokyo Nisshinbo Co., Ltd. Inside Nishiarai Kasei Plant (72) Inventor Hideo Senke 1-1-18 Nishiaraisakaecho, Adachi-ku, Tokyo Inside Nisshinbo Kasei Plant

Claims (5)

[Claims] 1. In the production of an elastic sleeper composed of a main body of concrete and an elastic portion covering the bottom surface thereof, a shape corresponding to the upper surface of the sleeper is formed on the bottom surface, and the surface corresponding to the bottom surface of the sleeper is on the upper side. Use an open formwork, place reinforcing bars or PC steel in this formwork, and then pour concrete into it. Before the concrete hardens, projections with a shape that increases peeling resistance are projected at multiple locations. The elastic member is pressed against the top surface of the concrete, the lid formwork is fixed from above, and the concrete is hardened. 2. An inverted trapezoidal projection having an enlarged dimension inside the concrete is projected on the surface of the elastic member pressed against the concrete as a projection having a shape increasing peeling resistance and shear resistance. Invention of 1 3. The invention according to claim 2, wherein an angle between the contact surface of the elastic member with the concrete and the side surface of the protrusion is set in the range of 45 ° to 84 ° as the protrusion for increasing the peeling resistance. 4. The invention according to claim 2, wherein the elastic member is thicker at the center and thinner at both side edges in a cross section in the transverse direction. 5. The invention according to claim 1, wherein a deaeration zone made of a long strip is arranged in contact with the resistance projection of the elastic member, and the deaeration zone before hardening of concrete is pulled out.