JP2012229593A - Gate-shaped free gradient existent culvert side ditch reconstruction method and concrete slab used therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce life cycle costs while prolonging an overall lifetime by suppressing parts to be reconstructed to an irreducibly minimum by performing partial reconstruction, even in a free gradient existent culvert side ditch comprising precast concrete of a gate-shaped structure and partial covering, by removing only a fixed upper slab of an upper part while burying the side ditch, by maintaining a lower part of a main body, and while also keeping a bottom face gradient.SOLUTION: An upper slab part of a gate-shaped free gradient existent culvert side ditch is removed. At the same time, an upper slab block 3 of precast concrete is erected and loaded in a fixed upper slab part removed position between walls of a main body to be maintained, which are obtained by slitting upper parts of both the side walls at a right angle, while accommodating and fixing expansion steel beams 11 on both side faces within the right-angle slits of the upper parts of both the side walls in the main body to be maintained.

Description

  TECHNICAL FIELD The present invention relates to a fixed upper plate part reconstructing method for a portal-type structure free-gradient existing culvert side gutter and a precast concrete used for remodeling.

Conventionally, the partial remodeling of the existing lid-hanging U-shaped side gutter and box-type culvert side gutter renews part of the drainage facility extension due to damage repairs and road surface improvement over time, so the cover plate is replaced or the upper part of the gutter is removed. The renovation is kept to the minimum necessary.
However, in the precast concrete free-gradient side groove, even if the cover plate can be replaced, it is a gate type structure, so only the fixed upper plate part of the main body can not be removed, and the renovation part exceeds the necessary range and the side groove main body is also replaced. It has become.

  Japanese Patent No. 3784820

  Even in the existing culvert side gutter with free-graded precast concrete with a portal structure, only the upper fixed upper plate is removed while being buried, the lower part of the main body is preserved, and partial reconstruction is possible while maintaining the bottom gradient By doing so, the number of renovation points is minimized and the overall useful life is extended, and the life cycle cost is reduced.

Using a cutter, only the fixed upper plate portion of the existing gate-type side groove is cut and removed, and further, a cut perpendicular to the upper plate portion cutting is attached to the upper part of both side walls to make the main body to be preserved.
And, the upper plate block made of precast concrete is erected and reconstructed at the place where the upper plate part is removed between the both side walls of the preserved main body, and the culvert side groove is remodeled. Reconstruction is completed by being stored and fixed in a right angle cut.

  The upper block is an extension of the main rebar where the overhanging steel beams on both sides are arranged as a reinforced concrete slab structure, and the section of the overhanging steel beam has a larger section modulus such as I-shaped steel plate and steel plate, which are larger than the width , Which has the necessary strength against bending and shearing force, fits in the notch of the preserved main body and the gap is fixed in a rigid state by filling the brazing material with epoxy resin or non-shrink mortar, This is the upper part of the culvert side groove that supports the design load.

The renovation is completed simply by cutting and removing the fixed upper plate part between both side walls of the existing gate-type side gutter, replacing the upper plate block made of precast concrete, and loading it.
Cutting and removing the upper plate with a cutter, cutting at right angles on both side walls, erection and loading of precast concrete upper plate block, and filling with epoxy resin, etc. are all done at the top, making it easy and reliable to remodel the existing culvert side groove Can be.

Even if it is a portal structure, the existing culvert side groove base that is stably installed in the ground with the adjustment concrete sandwiched on the base concrete is due to the cutter work at the top, thus damaging the preserved main body The spacing between both side walls is maintained without any problems.
Cutting and removing the fixed upper plate part and maintaining the gap between both side walls of the main body during the upper right angle cutting process on both sides of the main body can be carried out one after another by replacing the precast upper plate block while leaving one fixed upper plate part. It will be possible enough.

  The design load on the upper surface of the side groove is transmitted to the existing side groove preserving main body through the upper plate block fixed on both sides even after the reconstruction, and the stable structure of the uniform support is maintained.

  One type of pre-cast concrete upper block can be used, and the useful life is extended with the minimum necessary renovation, and the life cycle cost is reduced.

  It is a notched slope view showing an example of renovation using an upper slab block made of precast concrete in an existing free-graded culvert side gutter with a partially lidded structure with the top side removed. (B)   FIG. 2 is a perspective view of a gate-shaped precast concrete side groove main body and a drop lid in the embodiment of FIG.   It is sectional drawing along the AA line of FIG.   It is sectional drawing along the BB line of FIG.   It is sectional drawing along the CC line of FIG.   It is a slope view of the precast concrete upper slab block in the Example of FIG.

In general, in the case of damage repair of an old U-shaped side gutter or box-type gutter side gutter, renovation due to road surface modification, etc., the cover plate is replaced or the worn upper plate part is removed and renovated. This is also applied to the side ditch. In this case, the existing culvert side ditch base that has been buried is maintained and fixed while maintaining the main cross section and drainage gradient as a drainage facility.
And the upper block block by precast concrete is installed in the upper plate part cutting removal location of a gutter body.

  Right-sided notches are formed in the upper part of both side walls of the existing culvert side groove base so as to accommodate and fix the projecting steel beams on both sides of the precast concrete upper slab block.

  The overhanging steel beams on both side surfaces of the precast concrete upper slab block are welded and extended to the main rebar arranged as a reinforced concrete structure slab, and have necessary intrusion portions in the concrete.

FIG. 1 shows an embodiment in which an upper plate block is used in a free-gradient side groove having a portal type and partially covered structure, and (b) shows the state before and after the reconstruction.
(1) is an existing culvert side groove base, (2) is a side groove body, (3) is an upper plate block, and (4) is a fixed upper plate.
The existing culvert side groove base (1) is provided with right angle cuts (12) on the upper portions of both side walls (5) and (5) obtained by cutter-cutting the upper plate portion as shown in FIGS.
The existing underground gutter side ditch has been installed by placing the side ditch main body (2) on the upper surface of the base concrete (15) on the foundation (20) and placing the adjusted concrete (14) in accordance with the drainage gradient, but it has been repaired. In, the upper plate block (3) is preliminarily loaded by precast concrete between the walls where the fixed upper plate (4) is cut and removed by partial excavation.
The right angle cuts (12) at the tops of both side walls (5) and (5) accommodate the overhang steel beams (11) on both sides of the upper block (3) and the gap is fixed by filling with resin mortar (13). An upper plate of the culvert side groove is formed.

  The existing culvert side groove base (1) is a precast concrete product with a length of 2m, etc. as shown in FIGS. 1, 2, 3, and 4, and is a gate with both side walls (5) (5) and fixed upper plate (4). It is a block of a structure in which a drop lid (6) is supported by a small step (7) in a mold structure.

  As shown in FIGS. 1, 5, and 6, the upper block (3) has protruding steel beams (11) protruding from both sides of the main rebar (10) by welding and extending on both sides. The same length as the fixed upper plate (4) of the side groove main body (2) is supplied as a precast concrete product of 0.5 m or the like.

  Replacing the upper block (3) keeps the existing culvert side groove base (1), which has been buried, stable against lateral pressure, and maintains a fixed upper plate (4) with at least one fixed upper plate (4) remaining. In addition, if necessary, the other fixed upper plate (4) is cut and removed while temporarily holding a space (not shown), and this is recommended alternately.

The removal of the fixed upper plate in the existing side groove and the right angle cut at the upper part of both side walls are done by the concrete cutter, so it is within the scope of the general spread method.
In addition, the precast concrete upper block is equivalent to a conventional road concrete product in production and can be supplied at low cost.

DESCRIPTION OF SYMBOLS 1 Existing culvert side groove base 2 Side groove main body 3 Upper plate block 4 Fixed upper plate 5 Side wall 6 Drop lid 7 Small step 10 Main reinforcement 11 Overhang steel beam 12 Right angle cut 13 Resin mortar 14 Adjustment concrete 15 Base concrete 20 Foundation

Claims (2)

  In the renovation of an existing culvert side groove where the upper plate block is preloaded with precast concrete at the place where the fixed upper plate part is removed between the walls of the main body, where the fixed upper plate part is cut and removed at the same time, and the upper part of both side walls is cut at the same time. A renovation method for an existing culvert side gutter with a portal type free-gradient, characterized in that projecting steel beams on both sides of the block are housed and fixed in the right-angle cuts on both side walls of the main body.   Both sides of the upper body block that is installed and fixed in the upper plate part removal place on both side walls of the preserved main body, and is housed and fixed in the right angle cuts at the upper side walls of the preserved body in the upper plate block that rebuilds the existing culvert side groove. An overhanging block in which the overhang steel beam is welded and extended to a main reinforcing bar arranged as a reinforced concrete structure and has a necessary intrusion portion in the concrete.

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