JPH078433U - Stress concentration relaxation structure of radial gate foundation material - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce the stress concentration at the end of the bearing girder embedded in concrete among the foundation materials that rotatably hold the radial gate installed in the discharge channel of the concrete dam. . [Structure] In a bearing girder 3 embedded in concrete to rotatably hold an arm 2a of a radial gate provided in a water discharge channel 1a of a concrete dam 1, an end portion 6 of the bearing girder 3 is formed in an arc shape. While suppressing the concentration of stress on the end portion of the bearing girder 3, the filling material 7 is injected into the periphery of the bearing girder 3 and the end portion of the bearing girder 3 is moved by water pressure in a direction opposite to the water pressure acting direction. Even if the material is splashed and deformed, the deformation is absorbed by the filler 7, and it is possible to prevent the concrete from cracking around the end portion of the bearing girder 3.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a foundation material for rotatably holding a radial gate provided in a drainage channel of a concrete dam, and more particularly to a stress concentration relaxing structure at the end of a bearing girder embedded in concrete among the foundation materials.

[0002]

[Prior art]

 Generally, as shown in FIG. 2, a radial gate 2 is provided in a discharge channel 1a of a concrete dam 1, and the radial gate 2 is provided in front of a bearing girder 3 which constitutes a part of a foundation material. It is movably attached. As shown in FIGS. 3 and 4, the bearing girder 3 is composed of a steel box (or I) girder, is embedded in the concrete forming the concrete dam 1, and supports the hydraulic load received by the radial gate 2. It can be distributed and transmitted to the concrete part through the pressure girder 3. The end portion 4 of the conventional bearing girder 3 is formed to have a corner (see FIG. 4). The reference numeral 3a in FIGS. 2 to 4 indicates a pivot for pivotally attaching the rear end of the arm 2a of the radial gate 2 to the front surface of the bearing girder 3.

[0003]

[Problems to be solved by the device]

 By the way, in the conventional one as described above, when hydraulic load is applied to the end of the bearing girder, the end has a shape with corners, so that the concentration of force occurs in the concrete part, There is a problem that it causes concrete cracking. When the bearing girder receives a load, the end of the bearing girder tends to deform (rebound) to the side opposite to the water flow direction due to the characteristics of its structure, which promotes concrete cracking at the end. It will also happen.

The present invention is intended to solve such a problem, in which the end portion of the bearing girder embedded in the concrete of the concrete dam of the radial gate base material is formed in an arc shape. The purpose of the present invention is to provide a stress concentration relaxing structure for the radial gate base material, in which the concentration of stress on the concrete part is mitigated by further injecting a filler into the surrounding area.

[0005]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the stress concentration relaxing structure of the radial gate foundation material of the present invention is a steel girder member for the foundation material that rotatably holds the radial gate provided in the discharge channel of the concrete dam. And a bearing girder that is embedded in the concrete dam concrete, the end of the bearing girder is formed in an arc shape, and the filling material is injected around the bearing girder. Is characterized by.

[0006]

[Action]

 In the stress concentration relaxing structure of the radial gate base material of the present invention described above, the end portion of the bearing girder is formed in an arc shape to reduce stress concentration, which leads to suppression of cracking of concrete. In addition, against the amount of deformation such as splashing at the end of the bearing girder, the filler prevents direct contact between the end of the bearing girder and concrete and acts as a cushioning material to prevent cracking of concrete. To prevent.

[0007]

【Example】

 Referring to the drawings, a stress concentration relaxing structure for a radial gate base material according to an embodiment of the present invention will be described below. FIG. 1 is a sectional view thereof (corresponding to FIG. 4). In FIG. 1, the same reference numerals as those in FIGS. 2 to 4 indicate almost the same members. The bearing girder 3 of this embodiment is also composed of a steel box girder and is buried in the concrete of the concrete dam 1 to form a part of the foundation material of the radial gate. A rear end of an arm 2a of a radial gate provided in the water channel 1a is rotatably attached via a pivot 3a.

Each of the end portions 6 of the bearing girder 3 is formed in an arc shape having a radius R, and a filler 7 is poured around the arc portion. As the filler 7, for example, tar epoxy resin (synthetic resin) or the like is suitable. With the above-described structure, that is, by forming each of the end portions 6 of the bearing girder 3 in an arc shape, it is possible to reduce the stress concentration on the concrete at the end of the bearing girder 3. Further, by injecting the filling material into the periphery of the bearing girder 3, it is possible to absorb the deformation (rebound deformation) of the end of the bearing girder 3, and in combination with these effects, the bearing is supported. It is possible to reliably prevent cracking of the concrete around the end of the girder.

[0009]

[Effect of device]

 As described in detail above, according to the stress concentration relaxing structure of the radial gate base material of the present invention, the following effects and advantages are obtained. (1) By making each end of the bearing girder into an arc shape, it is possible to reduce the stress concentration on the concrete at the end of the bearing girder. (2) By injecting the filling material around the bearing girder, even if a load acts on the bearing girder and the end of the bearing girders up and deforms in the direction opposite to the load direction, this deformation becomes the filling material. Can be better absorbed. (3) Due to the above (1) and (2), there is an advantage that cracking of concrete around the end of the bearing girder can be reliably suppressed.

[Brief description of drawings]

FIG. 1 is a sectional view showing a stress concentration relaxing structure of a radial gate base material as an embodiment of the present invention.

FIG. 2 is a sectional view showing a conventional radial gate together with a concrete dam.

3 is an enlarged cross-sectional view showing an arrow A in FIG.

4 is a sectional view taken along the line BB of FIG. 3 and corresponding to FIG. 1.

[Explanation of symbols]

 1 Concrete Dam 1a Drainage 2 Radial Gate 2a Radial Gate Arm 3 Bearing Girder 3a Axis 4,6 End 7 Filling Material

Claims (1)

[Scope of utility model registration request] 1. A base material for rotatably holding a radial gate provided in a drainage channel of a concrete dam,
It is equipped with a bearing girder composed of steel girder members and embedded in the concrete of the concrete dam.The end of the bearing girder is formed in an arc shape and the filling material is injected around the bearing girder. The stress concentration relaxation structure of the radial gate foundation material is characterized by being