JPH0329922B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a jacket segment for reinforcing a bridge pier.

[Conventional technology] After bridge piers are constructed, if the surrounding riverbed declines and the depth of the foundation becomes short, the bridge piers may tilt due to scouring during floods, and the bridge photography function may stop. .

Furthermore, in order to increase the river area, it becomes necessary to dig down the river bed, which may require reinforcement of bridge foundations. Conventionally, methods for reinforcing such bridge piers have been adopted, such as foundation block insertion to prevent scouring and external sheet pile driving, but these have not been sufficiently effective.

[Problems to be Solved by the Invention] An object of the present invention is to provide a reinforcing segment that surrounds an existing pier and can protect and strengthen the pier by providing a deep-rooted and strong foundation wall. It is in.

[Means for Solving the Problems] The means of the present invention is a combination of a frame-shaped segment with open upper and lower sides and a cutting edge segment having a cutting edge plate projecting from the lower side in an eight-shape.

[Example] As shown in Fig. 1, the segment 1 consists of four pieces: an outer plate 1a, an inner plate 1b, and edge plates 1c and 1c', which serve as partition members between both plates 1a and 1b, formed of a material that can withstand lateral pressure. It is a combination of plates in a rectangular frame shape with the top and bottom open.
d, 1d' are left open. And this segment 1
As shown in FIG. 3, the outer plate 1a and the inner plate 1b are curved in order to form an annular joint.

Further, the blade mouth segment 2 is lower in height than the segment 1, and has an outer plate 2a and an inner plate 2.
Slits 2c, which serve as water passage holes, are provided at regular intervals in each of b, and cutting edge plates 2d and 2d' projecting outward from the lower edges of both plates 2a and 2b are provided in a figure-eight shape, with small openings at both left and right ends. Plate 2e,
A reinforcing rib 2d is provided in contact with the end of 2e'.

[Function] As shown in FIGS. 3 to 5, the two segments 1 and 2 are joined together in a ring shape around the pier foundation A by welding, bolting, or a combination of both to form a cylindrical body B.
form. This cylindrical body B has an outer wall C formed by the outer plate 1a, an inner wall D and a work space E formed by the inner plate 1b, and replacement gravel is piled up on both the inner and outer walls C and D of the cylindrical body B, and submerged from the hollow part of the segment. The gravel at the bottom of the bridge 4 is excavated, and in parallel with this, the water inside the cylindrical body is pumped up by a submersible pump 5 and discharged onto the replacement gravel at the bridge pier. As a result, the internal water level of the cylindrical body B is lowered, and the water outside the cylindrical body flows into the cylindrical body through the displacement gravel 7 and the slits 2c, and the synergistic effect of the downward flow and the displacement gravel causes friction on the circumferential surface. decreases,
The cylindrical body sinks without damaging the existing piers. That is, the replacement gravel 7 is thrown into the void created inside and outside the cylindrical body B by digging with the cutting edge plates 2d and 2d'. With the excavation, the replacement gravel immediately settles and fills the space between the cylindrical body B and the ground. (This construction method utilizes the subsidence construction method for structural foundation materials disclosed in Patent No. 929480, which was previously completed by the present inventor.) After the cylindrical body is sunk, the inside of the cylindrical body is filled with underwater concrete.
A new cylindrical body will be constructed surrounding the pier foundation A. The wall friction becomes even smaller due to the downward flow of the replacement gravel onto the wall, and the cylindrical body sinks due to its own weight, but if the sinking force due to its own weight is insufficient, girder 8 is fixed to the existing leg foundation A. and push in with jack 9.

After settling is completed, the hollow inside the cylindrical body is filled with concrete and mortar is poured into the replacement gravel. The exposed segments above the river bed are then dismantled and removed. In addition, 10 in the figure is the water surface during work,
11 indicates the river bed, and 12 indicates the existing bridge girder.

[Effects of the Invention] According to the reinforcing segment of the present invention, the pier is reliably reinforced, and the protection of the pier can be strengthened.

[Brief explanation of drawings]

Fig. 1 is a perspective view of a pier reinforcing segment according to the present invention, Fig. 2 is a perspective view of a cutting edge segment, and Fig. 3 shows a state in which a pier is reinforced using a pier reinforcing segment according to the present invention. Plan view shown, No. 4
The figure is also a longitudinal front view, and FIG. 5 is a longitudinal front view showing a state in which the cylindrical body is forcibly settled. 1...Segment, 2...Blade mouth segment,
2a...outer plate, 2b...inner plate,
2c...Slit, 2d, 2d'...Blade edge plate, 2e, 2e'...Edge plate.

Claims (1)

[Claims] 1. Assemble the outer plate, the inner plate, and the edge plate for forming the gap between the two plates into a frame shape so that the top and bottom are open, and insert a segment with a window hole for entry and exit of the diver in the edge plate, and a cutting edge plate at the lower end. A bridge pier reinforcement segment consisting of a protruding blade mouth segment in a figure eight shape.