JP5976728B2 - Widening method for existing structures - Google Patents

Description

  The present invention relates to a widening method for an existing structure that removes an obstacle such as an existing structure at a construction crossing and replaces the existing structure with a new structure having a large width.

  In the case of expanding the width of an underground structure such as an existing underground passage that is provided so as to cross under a rail or a road, conventionally, the existing structure is wider than the existing structure. A replacement method has been made.

  When it is necessary to renovate an underground passage that has been installed under the rail so as to cross the rail for many years, the conventional construction method first puts support piles on both sides of the underground passage and at night. After removing the ground below the rail on the underpass, laying the rail between the upper ends of the support piles and temporarily receiving it with a supported girder, destroying the existing subway and building a new underpass To be done.

  However, according to such an underpass renovation method, the rail is provisionally received with a provisional girder (construction girder), but it cannot be constructed without a covering that can install a provisional girder between the rail and the upper floor of the underground passage, In addition, since a temporary girder is installed, there is a problem that when the train passes through the construction site, it must be slowed down.

  In addition, it takes a lot of time to construct the temporary girder, destroy the existing underground passage, and construct a new underground passage. As the position becomes deeper, the underground passage has to be built deeper by that amount. Therefore, it is necessary to form an approach slope to the underground passage with a steep slope or lengthen the slope portion.

The following Patent Document 1 was proposed that the train does not need to slow down because it does not require any provisional girder or the like as in the prior art, and consists of an upper floor and a side wall, and at least the edge between the upper floor and the side wall is cut. In the existing structure, at least a plurality of steel plates are laid in parallel in the length direction of the existing structure on the upper surface of the upper floor, and the end portions of these steel plates are fixed to a stationary part, and the rear end side of the existing structure After the front end of the ready-made structure is made to coincide with its top end, the parallel steel plates are removed together with the upper floor of the existing structure while removing the side wall of the existing structure by appropriate means such as destruction. The existing structure and the ready-made structure are replaced by advancing the lower surface of the guide as a guide surface.
Japanese Patent Publication No. 06-105025

  At this time, prior to the promotion of the prefabricated structure, the prefabricated structure is propelled while propelling the prefabricated structure while removing both side walls of the existing structure and the lower floor by an appropriate means such as destruction. The temporary floor cart supporting the upper floor of the structure is advanced on the rail laid on the lower floor, and the upper floor is pushed out to the arrival side.

In the following Patent Document 2, the above-mentioned Patent Document 1 supports the upper floor at a certain height position by a temporary carriage that moves forward on the rail, but if there is a slight height difference on the upper surface of the rail, May move up and down during propulsion, and the ground surface may fluctuate.If the rail length direction and the propulsion direction of the ready-made structure that pushes the upper floor do not exactly match, Since the sliding frictional force is generated between the temporary carriage and the upper floor due to fluctuations in the lateral swing direction, a large thrust is required to overcome this frictional force and push the upper floor. It was proposed not only because it had to be laid, but also because there was a problem that the moving state of the upper floor had to be managed even during propulsion.
JP 2008-231863 A

  As shown in FIG. 25, the existing structure 1 is built in the ground below the rail 3, and the lower floor slab 11 of the existing structure 1 is separated from the side walls 1b and 1b, and the lower floor A temporary support 8 is installed on the plate 11 and the upper floor slab 1a is supported by the temporary support 8 to separate the upper floor slab 1a from both side walls 1b and 1b. A box 2 wider than the structure 1 is followed in abutting manner, and the box 2 is propelled from the box 2 side while destroying the side walls 1b and 1b, and the upper and lower floor slabs 1a and 11 are temporarily supported. The construction 8 is moved forward integrally and removed from the buried position under the rail to replace the existing structure 1 with the box 2 to obtain a widened structure.

  The side on which the box 2 follows the existing structure 1 is the start side 4 and the side from which the existing structure 1 is pushed out is the arrival side 5. First, a plurality of friction cut members are formed on the upper surface of the upper floor slab 1 a of the existing structure 1. The steel plates 6, 6, 6... 6 are laid in parallel with both end surfaces in the length direction being in contact with each other.

  Further, a plurality of rectangular cross sections each having the same size and the same shape as the steel plate 6 are placed on the upper surface at the same height position as the upper floor slab 1a on both sides of the upper floor slab 1a of the existing structure 1. The steel box roofs 7 are driven in parallel to form parallel pipes that are connected in the lateral direction, and a plurality of the same size and the same shape as the box roof 7 are formed downward from both side ends of the parallel pipes. Parallel pipes stacked in a line by sequentially placing the steel box-shaped roofs 7 in parallel in the vertical direction with the steel plates 6 mounted on the box-shaped roofs 7 facing outward. Form.

  The front end of the steel plate 6 is detachably fixed to the tip of the box-shaped roof 7, and an auger (not shown) is inserted into the box-shaped roof 7 in order to drive each box-shaped roof 7 into the ground. This is performed by propelling from the start side 4 toward the arrival side 5 while excavating the front ground.

  The front ends of these parallel pipes and the front end of the steel plate 6 laid on the upper surface of the upper floor slab 1a are projected to the arrival side 5, and the front ends of all the steel plates 6 on the parallel pipe are separated from the box roof 7. After that, the front ends of all the steel plates 6 aligned in a row and the front ends of all the steel plates 6 aligned in the vertical direction are in close contact with and supported by the side surfaces of the ground from which these steel plates 6 protrude. While the fixing frame 12 is integrally fixed by welding or the like, on the starting side 4, the connecting members 13 made of H-section steel or the like in which all the steel plates 6 protruding rearward are arranged orthogonally on these steel plates 6 are provided. All the steel plates 6 are connected together by being fixed by welding or the like.

  A lower floor slab 11 is slidably laid in the length direction of the existing structure 1 on the floor surface between the lower ends of the side walls 1b and 1b of the existing structure 1.

  At this time, the sliding surface material 9 is laid and fixed over substantially the entire width of the lower floor slab 11, and the lower floor slab 11 is laid on the sliding surface material 9 so as to be slidable in the length direction.

  As the lower floor slab 11, a plurality of steel pipes 11 a having the same cross-sectional rectangular shape as the box roof 7 are installed in parallel on the sliding face material 9, and these pipes 11 a and 11 a are sequentially connected to each other. Thus, the lower floor slab 11 having an upper surface formed on a smooth surface having a certain height is formed.

  After laying the lower floor slab 11 between the lower ends of the existing structure 1, the temporary support 8 is installed on the lower floor 11 and the existing structure is supported with the upper support 1 a supported by the temporary support 8. The upper floor slab 1a of the object 1 and the side walls 1b, 1b are separated.

  The temporary support 8 has a fixed base 8a that supports the lower base plate 8a1 on the upper surface of the lower floor slab 11, and an upper base plate 8a2 of the fixed base 8a at predetermined intervals in the length direction and the width direction. It comprises a plurality of jacks 8b that are erected and supported each time, and a plurality of support beams 8c that are erected and fixed between the upper end surfaces of these jacks 8b and 8b.

  In this way, after the upper floor slab 1a separated from the upper ends of the side walls 1b and 1b is supported by the temporary supporter 8, the same as the existing structure 1 is placed on the starting side 4 behind the existing structure 1. A box 2 having a height and a width wider than that of the existing structure 1 is installed and followed by the existing structure 1, and the front end surface of the upper floor portion 2a of the box 2 is connected to the rear end surface of the existing structure 1 and the rear side. The rear ends of the parallel box-shaped roofs 7 and 7 juxtaposed on both sides from the end surface are joined in a butting manner, and are arranged in parallel in the vertical direction downward from both ends of the parallel box-shaped roofs 7 and 7. The front end surfaces of the side wall portions 2b and 2b of the box 2 are joined to the rear end surfaces of the box-shaped roofs 7 and 7 in abutting manner, and the widthwise central portion of the lower floor portion 2c of the box 2 The front end face is joined to the rear end face of the lower floor slab 11 in a butted manner.

  Although the front end surface of the box 2 may be directly followed by the rear end surface of the existing structure 1, the blade edge having the same shape as the cross-sectional shape of the box 2 is provided on the front end surface of the box 2. The frame 14 is mounted, and a plurality of pieces for pressing the rear end surfaces of the upper floor slab 1 a and the lower floor slab 11 of the existing structure 1 and the rear end surfaces of the parallel box roofs 7, 7 to the front end surface of the blade frame 14. A middle push jack 15 is attached.

  On the other hand, a reaction force receiving wall member 10 is erected on the sliding surface member 9 at the rear of the box 2, and is fixed to the upper end of the reaction force receiving wall member 10 at the rear end of the steel plate 6 row. The connecting member 13 is connected by a connecting member 16 such as an anchor, and a plurality of propulsion jacks 17 are attached to the front surface of the reaction force receiving wall member 10, and the pushing jack 17 is pushed between the rear end face of the box 2. Interpose a frame.

  After the box 2 and the reaction force receiving wall member 10 are arranged on the starting side 4 in this way, when the intermediate push jack 15 is extended, the upper floor slab 1a of the existing structure 1 and the parallel box roofs 7, 7 The steel plate 6 fixed in a stationary state by the fixing frame 12 and the connecting member 13 is used as a guide to advance toward the arrival side 5 for a predetermined length while being slidably in contact with the opposite surface, and the lower floor of the existing structure 1 The plate 11 also slides on the sliding face material 9 and advances together with the upper floor plate 1a at the same time by a certain length.

  At this time, the temporary supporter 8 supporting the upper floor slab 1a also moves forward together with the upper and lower floor slabs 1a and 11 while holding the upper floor slab 1a at a certain height position.

  As described above, when the upper and lower floor slabs 11a and 11 of the existing structure 1 and the parallel box-shaped roofs 7 and 7 are propelled to the arrival side 5, the rear end portions of the side walls 1b and 1b of the existing structure 1 are obtained. Is exposed from the rear ends of the upper and lower floor slabs 1a and 11 by the propulsion length of the upper and lower floor slabs 1a and 11, and the exposed rear end portions of the side walls 1b and 1b are broken from inside the box 2 with a hammer or the like. Remove by appropriate means.

  After that, by extending the propulsion jack 17 disposed on the start side 4, the box 2 is propelled by substantially the same propulsion length as the box 2 with the steel plate 6 and the sliding face material 9 as a guide.

  At this time, the intermediate push jack 15 is contracted in accordance with the propulsion speed so that the propulsion force by the propulsion jack 17 is not transmitted to the existing structure 1 side.

  Next, the middle push jack 15 is extended again, so that the upper and lower floor slabs 1a and 11 of the existing structure 1 and the parallel box roofs 7 and 7 are integrally propelled to the arrival side 5 and then propelled. The rear part of the existing structure 2 exposed by the above is destroyed and removed, and then the box 2 is propelled by the same length following the existing structure 1 by extending the propulsion jack 17, and this operation is repeated. Thus, the existing structure 1 and the box 2 are replaced, and a passage made of the box 2 in which the existing structure 1 is widened under the rail is constructed.

  In this widening operation, the upper and lower floor slabs 1 a and 11 of the existing structure 1 pushed out to the arrival side 5 and the box-shaped roof 7 are cut each time they protrude to the arrival side 5 by a certain length.

  The box 2 may be divided into several parts in the length direction, and the box 2 may be replaced with the existing structure 1 by sequentially propelling the box 2 following the existing structure 1.

  In the conventional methods of Patent Document 1 and Patent Document 2, it is necessary to tear down the existing structure existing in the crossing section with the cross section face, and it is necessary to remove heavy objects in a narrow area, so that the construction speed is significantly reduced. Bring.

  Moreover, even if the box 2 which is wider than the existing structure 1 is made to follow the existing structure 1 in a butting manner, the relationship between them is extremely limited, and is limited to the case of the same height.

  The object of the present invention is to eliminate the inconvenience of the conventional example, remove the existing structure from the existing structure, and construct a new structure in which the existing structure is widened. It is to provide a widening method for an existing structure that can remove the existing structure safely and quickly and can improve the construction speed and the like.

In order to achieve the above object, the present invention according to claim 1 is a case where the existing structure is removed from the existing structure and a new structure formed by widening the existing structure is constructed by a box. For the construction of the new structure, from the vertical shafts installed on both sides as protective work for the construction section, the box roof is installed in a row through the entire circumference and the entire length at a position that matches the outer edge of the new structure. The box for the new structure is built in the box-shaped roof row, the inner ground surrounded by the box-shaped roof row and the box located behind it are integrated, and the inner ground is not excavated. Extrude, box roof and inner ground are removed, box is left as a new structure, and the existing structure is removed by installing a temporary support in the inner space of the existing structure. A thin steel plate that is a friction cut member is installed according to Packed with a state where the upper and received temporary is cut and separated and the combined existing structures in new construction edge by causing diced perform core boring conflict points between new structure to push the box-shaped roof column Thus, the gist is to push the existing structure enclosed by the box-shaped roof row together with the internal ground to the arrival side, and to disassemble it there.

  According to the first aspect of the present invention, the construction cost can be reduced by shortening the time required for removing the existing structure at the crossing face face (shortening the construction period), compared to the conventional box body propulsion and towing method. Since it is possible to remove the existing structure at the part, safety can be improved. In addition, by separating the punched portion and the remaining portion, it is possible to reduce the amount of inner air filling.

In addition, since the part to be pushed out of the existing structure and the part to be left are separated by a friction cut member, the existing structure surrounded by the box-shaped roof row can be smoothly pushed out to the arrival side together with the internal ground, and the new structure The propulsion or towing of the object can be performed without resistance because the friction cut member is interposed in the part of the existing structure that is left behind.

  The present invention according to claim 2 is characterized in that a thin steel plate as a friction cut member is disposed on the box-shaped roof so as to reduce frictional resistance during the propulsion or towing of the box for a new structure and the surrounding ground. The gist is to cut the edges.

  According to the second aspect of the present invention, the box-shaped roof row can be pushed out without resistance by the action of the friction cut member.

According to the third aspect of the present invention, the existing structure has an upper floor slab having a constant width and a constant thickness over the entire length, a lower floor slab, and upper and lower end surfaces integrated with the lower surfaces of both side ends of the upper floor slab and the lower floor slab. This is a concrete structure with a rectangular cross section consisting of both side walls of a certain height that are connected to the wall, and the gist is that after core boring, filling is performed in the gap of the existing structure. .

According to the third aspect of the present invention, the existing structure can be stabilized after the core boring.

  As described above, the widening method for an existing structure according to the present invention removes the existing structure from the existing structure and constructs a new structure in which the existing structure is widened. There is no particular limitation on the relationship of the sheath width, and the existing structure can be removed safely and quickly, and the construction speed and the like can be improved.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. 1 to 9 are longitudinal side views of respective steps showing one embodiment of the widening method of an existing structure of the present invention, FIGS. 10 to 18 are front views of the same, and FIGS. 23 to 25 showing the conventional example. The same components are given the same reference numerals.

  In the figure, reference numeral 1 denotes an existing structure. The upper and lower slabs 1a and 1c having a constant width and a constant thickness over the entire length, and the upper and lower end surfaces are integrated with the lower surfaces of both side ends of the upper and lower slabs 1a and 1c. Is a concrete structure having a rectangular cross section composed of both side walls 1b and 1b having a constant height, and is not shown in the figure, but this existing structure 1 is crossed under the rail or under the passage. It is built in the ground below this rail.

  The existing structure 1 is widened by replacing the existing structure 1 with a new structure having a horizontal box 2 made of a concrete structure having a height different from that of the existing structure 1 and having a lateral width larger than that of the existing structure 1. In this case, as shown in FIGS. 14 to 18, a part of the upper floor slab 1 a of the existing structure 1 or a part below it is removed and a new structure is constructed by a box.

  In order to widen the existing structure 1 by replacing it with the horizontally long box 2, the side where the box 2 follows the existing structure 1 is the start side 4, and the side which pushes the existing structure 1 is the arrival side 5. The temporary earth retaining member 21 is installed with a sheet pile or the like. (See Figure 3)

  First, a temporary support 8 is provided in the inner space of the existing structure 1, and a steel plate 6 that is a friction cut member (edge cutting material) is installed below the upper floor slab 1a in accordance with the outer edge of the new structure. The steel plate 6 may be a single large plate, or a plurality of strip-shaped steel plates are laid in parallel with both end faces in the length direction being in contact with each other.

  The upper floor slab 1a and the steel plate 6 of the existing structure 1 are filled with a grout material 20 to eliminate voids.

  Here, the installation method of the new structure by the box 2 will be described first.

  Here, the installation method of the new structure by the box 2 will be described first. 19 and 22 are explanatory diagrams showing the respective steps. Box roofs (steel roofs of rectangular cross section 1,000 × 1,000) are formed from the shafts on the starting side 4 and the reaching side 5 installed on both sides as protective work in the construction zone. 7 are arranged at a position matching the outer edge of the box 2, and are arranged in a row through the entire circumference and the entire length.

  A thin steel plate 6 that is a friction cut member is stacked on the box-shaped roof 7. The steel plate 6 is intended to reduce the frictional resistance during the promotion or towing of the box 2 and to cut the edge with the surrounding ground.

  A plurality of rectangular steel box roofs 7 having a rectangular cross-section on which steel plates 6 are placed are driven in parallel to form a side-by-side parallel box-shaped roof. A plurality of steel box-shaped roofs 7 of the same size and shape as the box-shaped roof 7 are vertically directed downward from above with the steel plates 6 mounted on the box-shaped roof 7 facing outward. The parallel box roofs stacked in a line are formed by driving in parallel in the direction.

  The front end of the steel plate 6 is detachably fixed to the tip of the box-shaped roof 7, and an auger (not shown) is inserted into the box-shaped roof 7 in order to drive each box-shaped roof 7 into the ground. This is done by propelling from the arrival side 5 toward the departure side 4 while excavating the front ground.

  In the illustrated example, the box-shaped roof 7 is inserted from the arrival side 5 toward the departure side 4, but conversely, it may be inserted from the departure side 4 toward the arrival side 5.

  The front ends of these parallel box-shaped roofs 7 are protruded to the starting side 4, and the front ends of all the steel plates 6 on the parallel box-shaped roofs 7 are separated from the box-shaped roofs 7, and these are aligned in a row. The front ends of all the steel plates 6 and the front ends of all the steel plates 6 arranged in the longitudinal direction are in close contact with and supported by the side surfaces of the ground from which these steel plates 6 protrude by welding or the like. On the arrival side 5, all the steel plates 6 projecting rearward are connected to each other by connecting members (not shown) made of H-section steel or the like arranged orthogonally on these steel plates 6. 6 are connected together by fixing by welding or the like.

  Note that the operation of separating the front end of the steel plate 6 from the box-shaped roof 7 and the operation of fixing the end may be performed at any time before the replacement of the existing structure 1 and the box 2 is started.

  Next, the box 2 is built in the mine on the start side 4, and the box-shaped roof 7 and the internal ground 22 are united and pushed out to the arrival side 5 without excavating in the tunnel and replaced with the box 2. The internal ground 22 of the construction section is pushed up and down and left and right with the box-shaped roof 7, and both the starting and reaching both ends are restrained by the temporary earth retaining member 21 of the shaft.

  The box 2 is pushed out by providing a reaction force receiving wall 19 in the pit on the starting side 4, attaching a plurality of propulsion jacks 17 on the front surface of the reaction force receiving wall 19, and interposing a strut 18 as necessary. Do it.

  Although not shown, a push frame may be interposed between the propulsion jack 17 and the rear end surface of the box 2.

  The box-shaped roof 7 pushed out to the vertical shaft on the arrival side 5 is collected and the earth ground 22 is discharged.

  When constructing a new structure with such a box 2, in order to stabilize the existing structure 1, a filling operation (not shown) is performed in the gap as necessary.

  Then, the existing structure 1 is cut and separated according to the outer edge of the new structure. In this state, the upper part of the existing structure 1 is temporarily received by the temporary supporter 8, and the core boring is performed at the conflicting position with the new structure (side wall of the existing structure 1). In order to prevent the inflow of earth and sand, etc., curing between cored parts is performed as necessary.

  The box-shaped roof 7 is arranged in accordance with the outer position of the box 2. However, as shown in FIG. 14, the box-shaped roof 7 is disposed at a portion where the existing structure 1 and the box 2 overlap. Is not placed.

  Thus, the construction of the box roof 7 and the installation of each box roof 7 in the ground are achieved by inserting an auger (not shown) into the box roof 7 while excavating the front ground. Propulsion is performed from the side 5 toward the starting side 4, and the box-shaped roof 7 is arranged at a position that matches the outer edge of the box 2, and is installed through the entire circumference and the entire length. At that time, the lower part of the existing structure 1 that has been cut and separated from the existing structure 1 is surrounded by the inner roof 22 inside the box-shaped roof 7. Further, the upper and lower portions of the existing structure 1 are cut off by the steel plate 6.

  The steel plate 6 laid on the upper surface of each box-shaped roof 7 and the steel plate 6 that cuts the upper and lower portions of the existing structure 1 are integrated with a connecting member made of a fixing frame, H-shaped steel or the like by welding or the like. You may make it connect.

  The box 2 and the existing structure 1 in the cross section of the box 2 are connected to the pusher 23 on the front surface of the box 2 and are pushed out together with the box-shaped roof row and the inner ground 22 surrounded by the box-shaped roof row to the arrival side. .

  The box-shaped roof 7, the internal ground 22, and the existing structure 1 that have been punched out by the light part on the arrival side 5 are removed.

  The box 2 is pushed out to a predetermined position to complete a new structure.

  Although the said embodiment showed the case where the existing structure 1 and the new structure by the horizontal elongate box 2 protrude the outer floor slab 1a of the existing structure 1 and the slightly lower side outside the new structure, FIG. 23, FIG. As shown in FIG. 5, the present invention can be similarly applied to a case where not only the upper part of the existing structure 1 but also the lateral part protrudes.

It is a vertical side view of the 1st process which shows one Embodiment of the widening construction method of the existing structure of this invention. It is a vertical side view of the 2nd process which shows one Embodiment of the widening construction method of the existing structure of this invention. It is a vertical side view of the 3rd process which shows one Embodiment of the widening method of the existing structure of this invention. It is a vertical side view of the 4th process which shows one Embodiment of the widening construction method of the existing structure of this invention. It is a vertical side view of the 5th process which shows one Embodiment of the widening construction method of the existing structure of this invention. It is a vertical side view of the 6th process which shows one Embodiment of the widening construction method of the existing structure of this invention. It is a vertical side view of the 7th process which shows one Embodiment of the widening method of the existing structure of this invention. It is a vertical side view of the 8th process which shows one Embodiment of the widening construction method of the existing structure of this invention. It is a vertical side view of the completed state which shows one Embodiment of the widening method of the existing structure of this invention. It is a front view of the 1st process which shows one Embodiment of the widening method of the existing structure of this invention. It is a front view of the 2nd process which shows one Embodiment of the widening method of the existing structure of this invention. It is a front view of the 3rd process which shows one Embodiment of the widening method of the existing structure of this invention. It is a front view of the 4th process which shows one Embodiment of the widening method of the existing structure of this invention. It is a front view of the 5th process which shows one Embodiment of the widening construction method of the existing structure of this invention. It is a front view of the 6th process which shows one Embodiment of the widening construction method of the existing structure of this invention. It is a front view of the 7th process showing one embodiment of the widening method of the existing structure of the present invention. It is a front view of the 8th process which shows one Embodiment of the widening method of the existing structure of this invention. It is a front view of the completed state which shows one Embodiment of the widening construction method of the existing structure of this invention. It is explanatory drawing of the 1st process which shows the installation method of the new structure in the widening method of the existing structure of this invention. It is explanatory drawing of the 2nd process which shows the installation method of the new structure in the widening method of the existing structure of this invention. It is explanatory drawing of the 3rd process which shows the installation method of the new structure in the widening method of the existing structure of this invention. It is explanatory drawing of the 4th process which shows the installation method of the new structure in the widening method of the existing structure of this invention. It is a front view which shows 2nd Embodiment of the widening construction method of the existing structure of this invention of this invention. It is a front view which shows 3rd Embodiment of the widening method of the existing structure of this invention of this invention. It is a side view partly cut away showing a conventional example.

DESCRIPTION OF SYMBOLS 1 Existing structure 1a Upper floor slab 1b Side wall 1c Lower floor slab 2 Box 3 Rail 4 Starting side 5 Reaching side 6 Steel plate 7 Box roof 8 Temporary support 9 Sliding surface material 11 Lower floor slab 15 Middle push jack 17 Propulsion jack 18 Strut 19 Reaction force receiving wall 20 Filling work 21 Temporary earth retaining member 22 Inner ground pile 23

Claims (3)

When this existing structure is removed from the existing structure and a new structure formed by widening the existing structure is constructed with a box,
The construction of the new structure is set up as a row, penetrating the entire circumference and full length from the vertical shafts installed on both sides as protective works of the construction section, at a position that matches the outer edge of the new structure,
A box for a new structure was built on the start side, and the boxed roof row and the inner ground surrounded by the boxed roof row and the box located behind it were integrated, and the inner ground was not excavated and reached. Extruded to the side, the box-shaped roof and the inner ground are removed, and the box is left as a new structure.
The existing structure was removed by installing a temporary support in the inner space of the existing structure, installing a thin steel plate as a friction cut member along the outer edge of the new structure, filling it, and temporarily receiving the upper part. In the state, the existing structure is cut and separated according to the outer edge of the new structure by performing core boring at the location of conflict with the new structure and cutting and separating it.
A widening method for an existing structure, characterized in that by pushing out a box-shaped roof row, the existing structure surrounded by the box-shaped roof row is pushed out to the arrival side together with an internal ground, and disassembled there.   2. The existing roof according to claim 1, wherein a thin steel plate as a friction cut member is disposed on the box-shaped roof to reduce frictional resistance and to cut off the surrounding ground during propulsion or towing of a box for a new structure. Structure widening method. The existing structure consists of an upper floor slab and a lower floor slab that have a constant width and thickness over the entire length, and a constant height in which the upper and lower end surfaces are integrally connected to the lower surfaces of both side ends of the upper floor slab and the lower floor slab. 3. A widening method for an existing structure according to claim 1 or 2, wherein the structure is a concrete structure having a rectangular cross-section composed of both side walls of the inner wall, and after the core boring, filling is performed in a gap portion of the existing structure.

Images