JPH0571219U - Supporting member - Google Patents

Abstract

(57) [Abstract] [Purpose] The bearing, which is the contact point between the upper structure and the lower structure in the bridge of a continuous girder bridge such as an expressway, is advantageous in terms of economy because a fixed bearing is advantageous. Cracks are likely to occur at the seams of plate concrete. Therefore, during concrete pouring, the movable bearing is provided so that stress can be easily released, and an auxiliary member for providing the function as a fixed bearing after completion is provided. [Structure] This auxiliary member includes left and right side surfaces of a rising portion 21 of a lower shoe 20 and left and right stopper portions 31, 31 of an upper shoe 30.
And a pressing surface member 41 having an arcuate surface that is pressed in line contact with the side surface of the rising portion 21 of the lower shoe, and a spacer plate 42 for adjusting the wall thickness. It is a laminated body having the liner plate 43 as a main component.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an auxiliary member for supporting a bridge or a structure.

[0002]

[Prior Art]

 Supports for bridges and structures are important members that serve as points of contact between upper and lower structures to transmit loads and to accurately and smoothly perform the behavior of the entire structural system. For bridges such as highways, bridges are erected via bearings on piers that are erected with a predetermined span distance. In FIG. 4 (the figure is an example of a continuous girder bridge), 10, 10, ... Are piers, 50 is a bridge body, and bearings S1, S2, are provided between the bridge body 50 and each pier 10, 10 ,. ... is installed.

The bearing is composed of a lower shoe and an upper shoe. A bearing that allows the upper shoe to slide in the bridge axis direction with respect to the lower shoe is called a movable bearing (movable shoe), and a bearing that substantially restrains this is called a fixed bearing (fixed shoe). In FIGS. 5 [I] and [II] ([I] shows a movable bearing and [II] shows a fixed bearing), 20 is a lower shoe and 30 is an upper shoe stacked on the lower shoe 20. The lower shoe 20 and the upper shoe 30 are plate-like blocks made of steel, cast steel or the like, the lower shoe 20 has a rising portion 21, and the upper shoe 30 faces each of the left and right side surfaces of the rising portion 21 of the lower shoe. It has stopper portions 31, 31. The lower shoe 20 is fixed to the piers 10, 10, ... As the lower structure, and the upper shoe 30 is attached to the bridge body 50 as the upper structure. In the movable bearing of the same figure [I], the side surface 211 of the rising part 21 of the lower shoe 20 and the upper shoe 30 are arranged so that the upper shoe 30 can slide in the arrow x direction (bridge axis direction) with respect to the lower shoe 20. A gap (G) (the gap width (l) thereof is, for example, 30 to 80 mm) is provided between the stopper portion 31 and the end surface 311 of the stopper part 31, while the gap width in the fixed bearing shown in the [II] diagram is Usually, the movement of the upper shoe 30 in the bridge axis direction is substantially restrained at about 2 mm.

[0004]

[Problems to be solved by the invention] Bridges are roughly classified into simple girder bridges with many joints and continuous girder bridges with few joints, depending on the connection type of bridges erected on piers. The demand for road surfaces with good running performance has increased along with the demand for improved seismic resistance, and in recent years, continuous girder bridges with few seams are being adopted to meet these demands. For continuous girder bridges, it is advantageous to use multi-point fixed bearings for economical reasons. However, there are still few examples in Kotetsu girder bridge. The most problematic issue when applying the multi-point fixed bearing type to steel continuous girder bridges is that cracking tends to occur in concrete during the placing of floor slab concrete.

This will be described by taking the four span continuous girder bridge shown in FIG. 4 as an example. Of the bearings S1 to S5, for example, only the central bearing S3 is a fixed bearing and the other bearings are movable bearings. While the above-mentioned problem of cracks is hardly generated in the one-point fixed bearing structure, for example, a three-point fixed bearing structure is used in which only the bearings S1 and S5 at both ends are movable bearings and the remaining bearings S2 to S4 are fixed bearings. When adopted, cracks are likely to occur in the vicinity of the pouring seam after the completion of the slab concrete pouring. With a one-point fixed bearing, the stress can be easily released even if axial tensile stress due to temperature changes etc. occurs after placing concrete, whereas with a multi-point fixed bearing, This is because it is difficult to release the stress, and stress concentrates especially near the casting joint. Therefore, in order to make it possible to apply the multi-point fixed bearing structure to steel continuous steel girder bridges, the number of movable bearing bearings should be increased during concrete casting, and this should be converted into a fixed bearing in the completed system. Is an important design condition. In the example of FIG. 4, it is necessary for the bearings S2 and S4 to function as movable bearings during concrete pouring, and to function as fixed bearings in the completed system. The present invention has been made for the purpose of solving the above problems.

[0006]

[Means and Actions for Solving the Problems]

 The bearing assisting member according to the present invention is for changing a movable bearing, in which the left and right stopper portions 31 and 31 of the upper shoe 30 face to each other on the left and right side surfaces of the rising portion 21 of the lower shoe 20, to a fixed bearing. A pressing surface member 41 which is a block fitted in the play and has an arc surface which is pressed in line contact with the side surface of the rising portion 21 of the lower shoe 20, and depending on a gap width dimension between the play. It is characterized in that it is a laminated body including a spacer plate 42 for adjusting the thickness which is increased and decreased and a liner plate 43 as main constituent members.

Hereinafter, the present invention will be described with reference to the drawings illustrating an embodiment. FIG. 1 is an exploded view of the bearing assisting member of the present invention into its constituent parts. Reference numeral 40 in FIG. 2 is an auxiliary member of the present invention in which the constituent members are laminated and integrated into a predetermined block shape. The member is shown. FIG. 3 shows a state in which the auxiliary member 40 is inserted into the play between the upper and lower shoes 20, 30 and fixed to the stopper portion 31 of the upper shoe 30. In FIG. 1, 41 is a pressing surface member, 42 is a spacer plate, and 43 is a liner plate. Numerals 45, 45 are machine screws for assembling the above-mentioned members 41, 42, 43 into a block 40 having a predetermined shape, and numeral 44 is a bisplay therefor. Small screw insertion holes a and b are formed through the screw plate 44, the liner plate 43, and the spacer plate 42, respectively. Although not shown in the figure, screw holes for screwing the tip portions of the machine screws 25, 25 are formed in the rear surface of the pressing surface member 41 (the surface facing the spacer plate 42) with an appropriate depth. Has been.

The front surface 411 of the pressing surface member 41 is a contact surface with the side surface of the rising portion 21 of the lower shoe 20. In the present invention, this is an arc surface having an appropriate curvature, and the contact with the rising portion 21 of the lower shoe is a line contact (Hertz contact). Thus, unlike the conventional fixed bearing (the contact between the side surface 211 of the lower shoe rise portion and the end surface 311 of the upper shoe stopper is a surface contact), the rotational displacement of the upper shoe 30 relative to the lower shoe 20 is smoothed. Can be absorbed into. The radius of curvature of the contact surface 411 may be appropriately determined according to the load applied to the contact surface. The side surface of the pressing surface member 41 is formed with screw holes a and b for mounting a member 47 described later.

The spacer plate 42 is a thin plate material (the plate thickness is, for example, about 1 mm) for finely adjusting the total wall thickness of the auxiliary member 40. The number of stacked layers is determined according to the gap width (l) between the clearances (G) between the upper and lower shoes 20, 30. That is, when the auxiliary member 40 is applied to the play space (G) after the floor slab concrete is placed, the number of the spacer plates 42 is determined based on the measured value of the gap width (l), so that It is possible to give an appropriate total wall thickness corresponding to the size of the gap width of (G).

The liner plate 43 is a member that occupies most of the entire thickness of the auxiliary member 40 together with the pressing surface member 41, and is suitable for the size of the clearance (G) to which the auxiliary member 40 is applied. Board thickness is given. The pressing surface member 41, the spacer plate 42, and the liner plate 43 are superposed on each other as described above, and are joined to the screw plate 44 by machine screws 45, 45 to form the block-shaped auxiliary member 40. Although the spacer plate 42 is interposed between the pressing surface member 41 and the liner plate 43 in the drawing, it may be interposed between the liner plate 43 and the screw plate 44.

Since the above-mentioned auxiliary member 40 is fitted in the clearance (G) between the upper and lower shoes 20 and 30 and becomes a part of the bearing structure, damage due to corrosion or the like should not occur over a long period of time. Therefore, the constituent members 41, 42, 43, 44, etc. are made of a corrosion-resistant alloy material such as stainless steel. Further, since the front surface 411 of the pressing surface member 41 is pressed against the side surface 211 of the lower rising portion 21 by linear contact, a material having a high hardness such as a special material such as a special material is sufficient to withstand the load of the horizontal force in the axial direction. It is preferable to apply stainless steel (such as C13B). For the same reason, it is desirable that the side surface 211 of the rising portion 21 of the lower shoe, which the pressing surface member 41 makes line contact with, also has a high hardness surface. However, in that case, it is not necessary to form the lower shoe 20 or the rising portion 21 thereof entirely with a hard material, and as shown in FIG. 2, a hard bearing surface member 212 is formed in a region where the pressing surface member 41 makes line contact. The structure may be such that an alloy material (similar to the pressing surface member 41, special stainless steel C13B, etc.) is embedded.

The auxiliary member 40 is inserted into the free space (G) between the upper and lower shoes and is fixed to the upper shoe 30. An example of the installation and fixing mode will be described with reference to FIG. 2. Reference numeral 47 is a member (mounting member) for fixing the auxiliary member 40 to the upper shoe 30, one end side of which is fixed to the auxiliary member 40. The other end is fixed to the upper shoe 30. Therefore, screw holes a and b are provided on the side surface of the pressing surface member 41 of the auxiliary member 40, and screw holes c and d are provided on the side surface of the stopper portion 31 of the upper shoe 30, respectively. Corresponding to c and d, openings 47a and 47b are formed on one end side of the mounting member 47, and openings 47c and 47d are formed on the other end side. 48 and 50 are bolts, and 49 and 51 are washers.

The attachment member 47 is fixed to the side surface of the auxiliary member 40 by bolts 48, 48 passing through the openings 47 a, 47 b and screwed into the screw holes a, b of the pressing surface member 41 and tightened. .. The auxiliary member 40 to which the mounting member 47 is fixed is inserted into the clearance between the upper and lower gears 20 and 30, and bolts 50 and 50 are passed through the openings 47c and 47d on the other end side of the mounting member 47. By screwing into the screw holes c and d of 30 and tightening, the installation and fixing form of the auxiliary member shown in FIG. 3 is completed. As a result, the movable bearing functions as a fixed bearing. As the attachment member 47 in the illustrated example, a U-shaped member having bent edges formed at both upper and lower ends of the plate surface is used because the attachment member 47 is a side surface of the auxiliary member 40 and the upper shoe 30. The reason is that it is adhered to the base plate to improve the stability of the fixed state, but it does not necessarily have to be U-shaped and may be a flat plate member. Further, welding may be applied instead of using the bolts 48 and 50 as a fixing means of the attachment member 47 to the auxiliary member 40 and the upper shoe 30. Furthermore, it is also possible to omit the attachment member 47 and use a method of joining and fixing the auxiliary member 40 directly to the upper shoe 30 by welding.

The pressing surface member 41, which is one of the constituent members of the auxiliary member 40 of the present invention, is also useful as a stopper portion forming member of the upper shoe 30 in the fixed bearing. For example, when the support S3 in the continuous girder bridge shown in FIG. 4 is a fixed support as shown in FIG. 5 [II], the front portion 312 of the stopper portion 31 of the upper shoe 30 is notched and the pressing surface portion is formed at that portion. By modifying the structure in which the material 41 is bonded and fixed, the contact with the rising part 21 of the lower shoe becomes a linear contact, which is different from the conventional fixed bearing of the surface contact, and is a fixed bearing capable of absorbing the rotational displacement of the upper shoe 31. Will work.

[0015]

[Effect of the device]

 According to the present invention, the bearing of a bridge or structure can be structurally transformed from a movable bearing to a fixed bearing. For example, when constructing a continuous girder bridge, increase the number of bearings by movable bearings before placing concrete slabs, and after completing the placing, apply the bearing support member of the present invention to change to fixed bearings. As a result, it is possible to construct a continuous girder bridge with multiple fixed bearings without causing cracks in the floor slab concrete. In addition, the fixed bearing formed by using the bearing assisting member of the present invention is different from the conventional fixed bearing in which surface contact is made because the contact of the upper shoe stopper portion with the lower shoe rising portion is line contact. It is easy to absorb the rotational displacement of the upper shoe against the shoe and the stress release effect enhances the durability and stability of the structure.

[Brief description of drawings]

FIG. 1 is a perspective exploded view showing an embodiment of a bearing assisting member of the present invention.

FIG. 2 is an explanatory perspective view showing an example of how to attach a bearing assisting member of the present invention to a bearing.

FIG. 3 is a perspective view showing a state where a bearing assisting member of the present invention is attached to a bearing.

FIG. 4 is a schematic explanatory view of a bridge.

FIG. 5 is a perspective explanatory view of a bearing including an upper shoe and a lower shoe.

[Explanation of symbols]

20: Lower shoe, 21: Lower shoe rising part, 30: Upper shoe, 31: Upper shoe stopper, 40: Bearing support member, 41: Pressing surface member, 42: Spacer plate, 43: Liner plate, 45: Machine screw , 47:
Mounting members, S1, S2, ...: Bearings, G: Free space.

Claims (1)

[Scope of utility model registration request] 1. A movable bearing for changing a movable bearing, in which the left and right stopper portions 31, 31 of the upper shoe 30 face each other with a clearance on the left and right side surfaces of a rising portion 21 of the lower shoe 20, into a fixed bearing. It is a block to be fitted, the lower shoe 2
A pressing surface member 41 having an arcuate surface that is pressed to make a line contact with the side surface of the rising portion 21 of 0, and a spacer plate 42 for adjusting the wall thickness that is increased or decreased in accordance with the gap width dimension between the spaces.
And a liner plate 43 as a main component, which is a laminated body.