JPH0610309A - Burying type strain-diffusion joint work - Google Patents

Abstract

PURPOSE:To permit continous construction of pavement by a method in which anchors are provided through strain-diffusion sheets on both ends of axial direction of bridge of a box-strip part in such a way as to enable the expanded or contracted amount of the aperture to be uniformly shared to the upper asphalt mixture. CONSTITUTION:A box-strip part 1 is formed in the right angle direction of the bridge axis and a strain-diffusion sheet 2 is placed over the whole surface smoothened of the part 1. Both ends in the direction of the bridge axis of the sheet 2 are fixed by using fixing plates 3 and anchor bolts 4. The whole surface of the part 1 is then coated with a primer and packed with an asphalt mixture 5. Also, the face to be bonded with a bituminous sheet is coated with a primer and covered with the bituminous sheet 6. Furthermore, all the surface of construction section is coated with a primer and usual paving work is made over the bridge surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a buried strain diffusion joint method for expanding and contracting small and medium bridges. The buried type expansion / contraction device has a structure in which the expansion / contraction device itself is excluded from the surface of the pavement, and the same asphalt mixture as that used in the front and rear pavements is used in the upper part of the device to disperse and absorb the expansion / contraction amount of the girder. Conventionally, the expansion and contraction device of the bridge had to be exposed on the pavement surface, so it was damaged by the wheel load of a passing vehicle, snow removal work in the winter period, etc., affecting the running performance and safety of the vehicle. Recently, various methods such as the no-joint method, the hexalock method, the joint goose method, and the expanded metal method have been devised from the economical and repairability aspects of the expansion and contraction device.

[0002]

2. Description of the Related Art Heretofore, in this type, the following has been done. 1) Until now, buried joints have been devised by each company, but roughly divided it is that the free space is replaced with asphalt mixture of normal pavement to bridge pavement surface with different aggregate and binder, pavement surface is normal pavement Although there is no change, there are large-scale telescopic devices themselves, and also those requiring changes in the shape of the girder itself. 2) As a first example, there is SOMA Joint (Japan Liner Co., Ltd.) or Cut-off Joint (SHOBOND CONSTRUCTION Co., Ltd.), but since the pavement surface is different from the front and rear pavement bodies, it is not a purely embedded joint. I can't say. 3) The second example is the Laundry Expansion Joint (Shin Nihon Kken Co., Ltd.), but the equipment itself is large-scale and is not suitable for repair bridges. 4) As a third example, there is a suspended buried joint (Kobe Steel Co., Ltd.), but since the shape of the girder is special, it is not economical and versatile and is not suitable for repair bridges.

[0003]

The problems described in the prior art have the following problems. 1) In the example of 2) above, the substituted mixture is superior to the ordinary asphalt mixture in terms of stretchability, but the strain load at the center of the replacement portion is large and the amount of stretch (= strain) is large.
The construction is not evenly distributed over the entire construction width.
In addition, since the mixture used is a special one, there are problems in terms of workability and economy. 2) In the example of 3) above, the structure is such that the anchor is taken in the axial direction of the bridge and the expansion and contraction amount is loaded in a wider range, but the device itself is complicated, and there is a difficulty in economic efficiency. In this case, it cannot be used for repair bridges because it does not take into consideration the reinforcing bar cover of the floor slab. 3) In the example of 4) above, the shape of the girder itself must be changed, so examination from the design stage is required, and it is extremely difficult to use it in a repair bridge.

The present application has been made in view of the above problems of the prior art, and an object of the present application is to provide a device capable of solving the above problems.

[0005]

In order to achieve the above object, the present invention is as follows. 1) For the pavement of the bridge surface, use the same mixture as the front and rear pavements so that continuous pavement can be achieved. 2) In order to bear the amount of expansion and contraction of the clearance in a wider range, anchors are taken through the strain diffusion sheet in both the bridge axis direction of the box removal part. In this case, the length in the axial direction of the bridge varies depending on the amount of expansion and contraction of the bridge to be applied, but with a length of 50 to 100 cm the amount of expansion and
Corresponds to 20 mm. 3) To reduce the load on the anchor part, use a strain diffusion sheet whose stretchability does not change even at low temperatures. 4) To make it easier to apply to repair bridges, consider the cover of the floor slab so that the depth of the box removal part can be increased or decreased. In this case, there is no upper limit to the depth, but 20 to 40 mm is desirable. 5) A bituminous sheet is laid on the top of the box removal part in order to prevent water leakage from the pavement surface, cracks from the play area, anchor bolts, and cracks due to structural defects in the fixing plate.

[0006]

EXAMPLES Examples will be described with reference to the drawings. The method of the present invention comprises the following steps. 1st process-The box removal part 1 is provided in the direction orthogonal to a bridge axis, and the surface is made smooth. Second step: The strain diffusion sheet 2 is laid on the entire surface of the box removing part.

Third Step-Both axial ends of the strain diffusion sheet 2 are fixed using the fixing plate 3 and the anchor bolts 4. Fourth Step-A primer (adhesive) is applied to the entire surface of the box-extracted portion, and the asphalt mixture 5 is filled.

Fifth step-A primer is applied to the surface to which the bituminous sheet is adhered, and the bitumen sheet 6 is laid on the primer. Step 6-Apply a primer on the entire surface of the construction area, and then perform normal bridge surface pavement. The broken line in the figure represents the adhesive surface. In addition, it is possible to use a Laundry Expansion Joint (Shin-Nihon Kken Co., Ltd.) in which the entire box removing part is replaced with another structure.

The strain diffusion sheet 2 will be described in detail. For the strain diffusion sheet, natural and synthetic rubber chips mixed with a resin binder are used, and the standard physical property values are as shown in Table 1.

[0010]

[Table 1]

As the strain diffusion sheet, a ready-made sheet (leg pole 6015, leg pole 7020-III / Hodogaya Kenzai Kogyo Co., Ltd.) in which natural and synthetic rubber chips are mixed with a urethane resin binder and formed into a sheet is used. Originally, this is a surface layer material used for indoor and outdoor sports facilities, but it is superior to ordinary rubber sheets in heat resistance, cold resistance, adhesiveness, and durability.

Since the buried joint has a structure in which the expansion and contraction of the play portion is borne by the asphalt of about 1 m, the adhesion between the sheet and the asphalt determines the occurrence of cracks. In addition, since the sheet is likely to be sheared at the anchor portions at both ends, it is desired that the rubber does not deteriorate, and further, the compressive strength that does not hinder the asphalt pavement is required.

Therefore, it is important to note the following points when selecting. 1) The surface that contacts the asphalt (upper surface) has appropriate unevenness and good adhesion. 2) Those which do not extremely lose elasticity even at low temperatures (-15 to -20 ° C). 3) Durable, slow rubber deterioration. 4) Those that have a compressive strength that does not interfere with pavement.

The operation will be described together with the effects.

[0015]

Since the present invention is configured as described above, it has the following effects. 1) By using the same mixture as the front and rear pavements for the bridge surface pavement, the pavement can be performed continuously, resulting in economical efficiency, workability, vehicle running performance, workability for snow removal in winter, etc. Are better. 2) Anchors are provided at both ends in the bridge axis direction of the unboxed portion via strain diffusion sheets, so that the amount of expansion and contraction of the free space can be evenly distributed to the upper asphalt mixture.

3) By using a strain diffusion sheet having a small temperature dependency, the load on the anchor portion at a low temperature can be reduced as compared with a normal rubber sheet. 4) Since the depth of the box removal part can be increased or decreased, it can be easily applied to repair bridges. 5) By laying a bituminous sheet on the upper part of the box removal part, prevent water from seeping from the pavement surface, and further cut off cracks from the free space, anchor bolts, and cracks due to structural defects in the fixing plate that affect the bridge surface painting. be able to.

[Brief description of drawings]

FIG. 1 is a plan view.

FIG. 2 is an enlarged sectional view taken along line AA.

FIG. 3 is an enlarged view of a main part of the above.

[Explanation of symbols]

 1 Unboxing part 2 Strain diffusion sheet 3 Fixing plate 4 Anchor bolt 5 Asphalt mixture 6 Bituminous sheet

Claims (2)

[Claims] 1. A buried strain diffusion joint method comprising the following first to fifth steps. Step 1-Providing a box removal part in the floor slab under the bridge pavement.
2nd step-laying strain diffusion sheet on the whole surface of the box removing part. Third step-anchoring both ends of the strain diffusion sheet in the bridge axis direction. Fourth step-Applying an adhesive on the upper surface of the strain diffusion sheet and filling the asphalt mixture up to the floor slab surface. Fifth step-Applying an adhesive on the upper surface of the asphalt mixture in the unboxed portion and laying a bitumen sheet. 2. A laundry expansion joint in which the entire box removing part is replaced with another structure.
The buried strain diffusion joint method described.