JPS597440Y2 - Reinforcement structure for bent bolt holes in concrete segments - Google Patents

Description

[Detailed description of the invention] This invention relates to a reinforcement structure for a bent bolt insertion hole in a concrete segment.

As its name suggests, the concrete segment is shaped like a sector (arc).

Therefore, in terms of workability, it is most convenient to connect concrete segments of this shape to each other in the circumferential direction using bent bolts, and today, connections using bent bolts are beginning to replace connections using straight bolts. .

However, in the conventional connection using bent bolts, as shown in FIG. 1, the insertion hole 3 for the bent bolt 2 is provided directly in the concrete segment 1, and the inner wall surface of the insertion hole 3 is not reinforced in any way. It has not been done yet.

Therefore, when tightening is performed using an impact wrench or the like, for example, it is difficult to tighten strongly.

In such a case, the bent bolt 2 tends to straighten and presses the inner curved wall portion 3a of the insertion hole 3 outward strongly, resulting in damage to this portion.

This invention was made in view of the above circumstances, and its purpose is to provide a reinforcing metal fitting for a bent bolt insertion hole, which has a plurality of flanges extending radially outward and a hollow portion for insertion of the bent bolt inside. It is an object of the present invention to provide a reinforcement structure for a bent bolt insertion hole in a concrete segment that does not cause cracks or breakage in the inner wall of the insertion hole when buried.

An embodiment of this invention will be described in detail below based on the drawings.

FIG. 2 is an enlarged view of the main part of the reinforcing structure for the bent bolt insertion hole of the concrete 1 segment according to this invention.

In the figure, the reference numeral 5 indicates a concrete segment, and a joint hole 6 is provided in the inner curvature of the concrete segment 5.

A plurality of independent flanges 7 (three flanges were provided in this embodiment) on the outer periphery between the joint hole 6 and the end surface.

) with a hollow part of a predetermined curvature inside, that is, a bent bolt 8
A reinforcing metal fitting 10 having an insertion hole 9 is embedded therein.

By the way, as is clear from the figure, the shape of the flanges 7 of the reinforcing metal fitting 10 is a plurality of flanges 7 at appropriate intervals in the longitudinal direction so as to extend radially outward with respect to the central axis of the insertion hole 9. In the illustrated example, the amount of protrusion in the direction of the inner bay is small, and the amount of protrusion is increased in the direction of the outer bay.

FIG. 3 is a plan view taken along arrows III--III in FIG. 2.

FIG. 4a is a perspective view showing the structure of the reinforcing metal fitting 10 in an easy-to-understand manner.

The operation of the bending bolt insertion hole reinforcing structure based on the above structure will be explained below.

When connecting the concrete segments 5, 5, the bent bolt 8 is tightened with an impact wrench, etc.
A force acts on the member to cause it to extend in the direction of arrow A in the figure, that is, in a straight line.

This force is concentrated along the inner wall of the concrete segments 5, 5 via the reinforcing metal fittings 10, and when this force increases beyond a certain level, the inner wall is eventually pushed outward and destroyed.

However, in this invention, an independent flange 7 is provided on the outer periphery of the reinforcing metal fitting 10, so that the force in the direction of the arrow A can be transferred to, for example, the first
In the figure, since they are distributed over each flange 7, they are not concentrated along the inner wall of the reinforcing metal fitting 10.

The inner walls of the concrete segments 5, 5 are thus protected from bulging failure.

Note that even if the outer peripheral end of the flange 7 is partially missing in the circumferential direction and becomes gear-shaped or sprocket-shaped, there is no substantial difference in the reinforcing effect as used in the present invention.

In addition, when the auxiliary fitting is shaped using ductile, knobs remain on both edges of the hollow part, so if this is used, the thickness of the cylindrical wall of the reinforcing fitting can be made thinner, and the shaping process can be carried out smoothly. .

In addition, since the above structure allows the space within the hollow portion to be set wide, it can be effectively used as play when inserting the bent bolt, thereby facilitating smooth insertion.

Further, in the above embodiment, the end face of the reinforcing metal fitting for the bent bolt insertion hole was arranged flush with the end face of the segment, but for example, the end face of the metal fitting facing the left and right end sides of each piece of the segment could be slightly protruded or When connecting by recessing, the end faces of the metal fittings of adjacent segments may be configured to fit into each other, and by adopting such a structure, the connecting position of each segment 1 can be extremely smoothly achieved. It's convenient.

Since this invention has the above-mentioned structure and operation, it is possible to prevent the destruction and cracking of the inner curved wall of the joint part, which is unique to conchnaut segments using bent bolts, and strengthen the segment itself. can be achieved.

In addition, the connection can be made strong, and there is no need to worry about breaking or cracking when tightening the bolts, so the work can be done extremely smoothly, which has practical effects.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view showing the connection state of concrete segments using conventional bent bolts, Fig. 2 is an enlarged view of the main parts showing the bent bolt insertion hole reinforcement structure according to this invention, and Fig. 3
The figure is a plan view taken along arrows III--III of the same figure, and FIG. 4a is a perspective view of a reinforcing metal fitting provided with an independent flange. 5... Concrete segment, 7...
・Flange, 8...Bent bolt, 9...
・Hollow part (bolt insertion hole), 10...Bent bolt insertion hole reinforcement fitting.

Claims (1)

[Scope of utility model registration request] It has a bent bolt insertion hole 9 with a predetermined curvature, and a plurality of flanges 7 are provided at appropriate intervals in the longitudinal direction so as to extend radially outward with respect to the central axis of the insertion hole. This structure for reinforcing a bent bolt insertion hole in a concrete segment is characterized in that a shaped reinforcing metal fitting 10 is buried along the entire length between the joint hole and the end surface of the concrete segment.