JP6493362B2 - Removal method of existing concrete slab - Google Patents

Description

  The present invention relates to a method for removing an existing concrete floor slab, and more specifically, an existing installation that can reduce removal work on a bridge surface without cutting existing main girders and can suppress noise during the removal work. It relates to a method for removing concrete slabs.

  The bridge slab is a member that directly supports the load of vehicles passing through the bridge, and its damage has become a problem due to aging due to the aging of the bridge. The number of cases of replacement with floor slabs is increasing.

  On the other hand, when replacing an existing concrete floor slab, it is necessary to temporarily restrict the traffic on the bridge surface, which affects traffic. Therefore, it is important to control the traffic regulation period. It is also important to consider the surrounding environment, such as suppressing noise during construction when replacing existing concrete slabs.

  For this reason, as an elemental technology for replacing bridge floor slabs, existing concrete floor slab removal technology that can control the traffic regulation period by reducing the removal work on the bridge surface and also suppress noise during the removal work. Development has become an important issue.

  FIG. 8 is a view of the conventional general removal method for removing an existing concrete floor slab, as viewed from the direction of the bridge axis, schematically showing the situation when the existing concrete floor slab 102 of the bridge 100 is removed. It is a vertical sectional view.

  In this conventional general removal method, the existing concrete floor slab 102 of the bridge 100 is removed in the following steps 1 to 3.

1) Of the portions of the existing concrete floor slab 102, a portion 102A that is located between the existing main girders 104 adjacent to each other in the direction perpendicular to the bridge axis and that is not located above the upper flange 104A of the existing main girder 104 is replaced with a crane or the like. After making it in a state where it can be supported by the lifting means 200, both the outer sides of the upper flange 104A of the existing main girder 104 in the direction perpendicular to the bridge axis are cut with a concrete cutter in the bridge axis direction (the obtained cut surface is vertically cut in FIG. 8). The vertical cutting plane 120 is a vertical plane extending in the direction of the bridge axis), and the existing concrete floor slab 102 is made with a concrete cutter so that it can be easily lifted by the lifting means 200 such as a crane. Is also cut in the direction perpendicular to the bridge axis (the obtained cut surface is a vertical surface (not shown) extending in the direction perpendicular to the bridge axis). In the present application, “the direction perpendicular to the bridge axis” means a horizontal direction and a direction perpendicular to the bridge axis direction.

2) Of the parts of the existing concrete slab 102, a part 102A that is located between the existing main girders 104 adjacent to each other in the direction perpendicular to the bridge axis and is not located above the upper flange 104A of the existing main girder 104 is replaced with a crane or the like. It is lifted by lifting means 200 and removed. The existing concrete floor slab 102 to be removed at this stage is a portion 102A that is not located above the upper flange 104A of the existing main girder 104.

3) Since the upper surface of the upper flange 104A of the existing main girder 104 is melted with a slip stopper such as a slab anchor or a stud gibber, the existing concrete floor slab 102 positioned above the upper flange 104A of the existing main girder 104 The part 102B is removed by hand hanging using a concrete breaker or the like.

  In this conventional general removal method, it is necessary to cut both the outer sides of the upper flange 104A of the existing main girder 104 in the direction perpendicular to the bridge axis with the concrete cutter, so the bridge using the concrete cutter is used. Work time on the surface becomes longer. Moreover, the work of removing the portion 102B of the existing concrete floor slab 102 located above the upper flange 104A of the existing main girder 104 by hand is more time-consuming on the bridge surface than the removal work using a crane or the like. Takes a long time.

  For this reason, when replacing an existing concrete floor slab using a conventional general removal method when replacing the bridge floor slab, it takes a long time to work on the bridge surface and the time for traffic regulation is long. Become.

  On the other hand, the removal method of the existing concrete floor slab described in Patent Document 1 cuts the steel girder web in the existing concrete floor slab at the position to be replaced in the vertical direction along the bridge axis direction, and thereby the existing concrete floor slab. Is removed together with the upper web of the steel girder. For this reason, compared with the conventional general removal method about the existing concrete slab, the working time on a bridge surface can be shortened significantly.

  However, if the steel girder web is cut in the vertical direction along the bridge axis direction, the cross-sectional performance of the existing main girder is remarkably deteriorated. Therefore, it is necessary to reinforce the main girder before cutting. In addition, when the new floor slab is installed, the new floor slab is integrated with the steel girder upper flange and the upper part of the steel girder web. Ensuring joining accuracy and position adjustment with the girder web is an issue.

  Patent Document 2 discloses a bridge concrete floor slab cutting technique in which a bottom surface (haunch part) of a concrete floor slab is cut in a horizontal direction with an endless diamond wire saw.

  However, the work of cutting the slab of the concrete slab in the horizontal direction is an operation that requires a lot of labor and generates noise for a long time because the cut surface forms a long horizontal surface.

JP 2007-239365 A JP 2009-114688 A

  The present invention has been made in view of the above points, and is an existing concrete that can reduce the removal work on the bridge surface without cutting the existing main girder and can suppress noise during the removal work. It is an object to provide a method for removing a floor slab.

  This invention solves the said subject with the removal method of the following existing concrete floor slabs.

  That is, the first aspect of the method for removing an existing concrete floor slab according to the present invention is that the part of the existing concrete floor slab that is close to the upper flange of the existing main girder is in a substantially horizontal direction, and A drilling step of drilling in a direction substantially perpendicular to the bridge axis direction to provide a drilling portion, and the existing concrete floor by applying a force in a substantially vertical direction to the inner surface of the drilling portion provided in the drilling step An edge cutting step for cutting a plate and the existing main girder, and a lifting step for lifting the existing concrete floor slab that has been edge-cut with the existing main girder in the edge cutting step. This is a method for removing concrete floor slabs.

  A second aspect of the method for removing an existing concrete floor slab according to the present invention is that the portion of the existing concrete floor slab that is in a substantially horizontal direction at a portion adjacent to the upper flange of the existing main girder and the bridge shaft A cutting step of providing a cut in a direction substantially perpendicular to the direction, and an upper flange of the existing main girder of the existing concrete floor slab so as to include at least a part of the cut provided in the cutting step. A drilling step of drilling a portion adjacent to each other in a substantially horizontal direction and in a direction substantially orthogonal to the bridge axis direction to provide a drilling portion, and the drilling portion provided in the drilling step An edge cutting step of cutting the existing concrete floor slab and the existing main girder by applying a force in a substantially vertical direction to the inner surface, and the existing concrete floor slab that has been edge-cut with the existing main girder in the edge cutting step Lifting Degree and a removing method of the existing concrete slab, characterized in that it comprises a.

  According to a third aspect of the method for removing an existing concrete floor slab according to the present invention, a portion of the existing concrete floor slab that is close to the upper flange of the existing main girder is substantially in the horizontal direction and has a bridge shaft. A drilling step of drilling in a direction substantially perpendicular to the direction to provide a drilling portion, and at least part of the drilling portion provided in the drilling step, Among them, a cutting process in which a cut is provided in a portion in the vicinity of the upper flange of the existing main girder in a substantially horizontal direction and substantially orthogonal to the bridge axis direction, and the cutting process provided in the drilling process. An edge cutting step for cutting the existing concrete floor slab and the existing main girder by applying a force in a substantially vertical direction to the inner surface of the hole, and the existing concrete floor that has been edge cut with the existing main girder in the edge cutting step Lifting the plate up Degree and a removing method of the existing concrete slab, characterized in that it comprises a.

  In the present application, edge cutting refers to a portion in the vicinity of the upper flange of the existing main girder, or a boundary between the existing concrete floor slab and the upper flange of the existing main girder in a substantially horizontal direction. It means that the integrity of the existing concrete floor slab and the existing main girder is lost. Here, the crack is a concept including peeling that occurs at the boundary between the existing concrete floor slab and the upper flange of the existing main girder.

  When the existing concrete floor slab has a haunch portion that increases in thickness as it approaches the existing main girder, the existing concrete floor slab is positioned above the upper flange of the existing main girder. Thus, the hole-drilling portion is provided in a portion close to the upper flange and a thickened portion including the haunch portion.

  In the present application, the thickened portion of the existing concrete floor slab is a portion of the existing concrete floor slab having the haunch portion, located above the upper flange of the existing main girder and from the portion adjacent to the upper flange and the haunch portion. The thickened part of the existing concrete floor slab is a part provided so as to protrude downward from the general part of the existing concrete floor slab. The general part of the existing concrete floor slab is the part of the existing concrete floor slab having the haunch part, located between the existing main girders adjacent in the direction perpendicular to the bridge axis, It is a portion above the thickened portion corresponding to a portion moved in a direction parallel to the floor slab surface and perpendicular to the bridge axis direction. In addition, in this application, a haunch part is a site | part where thickness becomes thick as it approaches the existing main girder among the site | parts of an existing concrete floor slab, and the cross section becomes a triangle shape seeing from the bridge axis direction. It is a part.

  It is preferable that the drilling portion provided in the drilling step is provided so as to cut a slip stopper that is fused to the upper flange of the existing main girder.

  A cutting step of cutting a slip stopper fused to the upper flange of the existing main girder is further provided between the edge cutting step and the lifting step from a gap generated by the edge cutting step. Also good.

  In the present application, a gap generated by the edge cutting process may be referred to as an edge cutting portion.

  In the edge cutting step, by inserting a diameter expanding means capable of expanding in a substantially vertical direction into the hole portion provided in the hole drilling process and expanding the diameter expanding means in a substantially vertical direction. You may make it apply force to the inner surface of a drilling part in a substantially up-down direction.

  The diameter-expanding means is preferably a hydraulic-type arrow or a striking-type arrow.

  According to the present invention, when the existing concrete slab is removed, the work on the bridge surface can be reduced without cutting the existing main girder, and noise during the removal work can be suppressed.

The vertical sectional view seen from the direction of a bridge axis which shows the situation during implementation of the removal method of the existing concrete floor slab concerning a 1st embodiment of the present invention The vertical cross section seen from the bridge axis perpendicular direction which shows typically the situation after providing a drill part in the direction perpendicular to the bridge axis in the drilling process in the removal method of the existing concrete floor slab according to the first embodiment of the present invention Figure (sectional view taken along line II-II in FIG. 1) Similarly, a vertical sectional view seen from the bridge axis direction schematically showing the above situation The vertical cross section seen from the direction perpendicular to the bridge axis schematically showing a situation in which a force is applied to the inner surface of the drilling hole in the edge cutting process in the method of removing the existing concrete floor slab according to the first embodiment of the present invention. Figure (sectional view taken along line II-II in FIG. 1) Similarly, a vertical sectional view seen from the bridge axis direction schematically showing the above situation The figure which shows typically the condition of a cutting process in the removal method of the existing concrete floor slab which concerns on 2nd Embodiment of this invention. In the removal method of the existing concrete floor slab which concerns on 2nd Embodiment of this invention, it is a figure which shows each process typically, (A) The figure which shows the state after completion | finish of a cutting process, (B) Drilling process The figure which shows the state after completion | finish, (C) The figure which shows a border cutting process typically Vertical sectional view viewed from the direction of the bridge axis schematically showing the situation when the conventional general removal method for removing the existing concrete floor slab is used for removing the existing concrete floor slab 102 of the bridge 100

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the method for removing an existing concrete floor slab according to an embodiment of the present invention is applied to the removal of an existing concrete floor slab 12 of a bridge 10. explain.

(1) 1st Embodiment FIG. 1: is the vertical sectional view seen from the bridge-axis direction which shows typically the condition in implementation of the removal method of the existing concrete floor slab which concerns on 1st Embodiment of this invention.

  FIG. 2 is a view from a direction perpendicular to the bridge axis schematically showing a state after providing a drilling portion in a direction substantially perpendicular to the bridge axis in the drilling step in the method for removing an existing concrete floor slab according to the first embodiment of the present invention. FIG. 3 is a vertical cross-sectional view (a cross-sectional view taken along the line II-II in FIG. 1), and FIG. 3 is a vertical cross-sectional view as viewed from the bridge axis direction schematically showing the situation.

  FIG. 4 is a view from a direction perpendicular to the bridge axis schematically showing a state in which a force is applied in a substantially vertical direction to the inner surface of the drilled hole in the edge cutting process in the method for removing an existing concrete floor slab according to the first embodiment of the present invention. FIG. 5 is a vertical cross-sectional view (cross-sectional view taken along the line II-II in FIG. 1), and FIG. 5 is a vertical cross-sectional view as viewed from the bridge axis direction schematically showing the situation.

  After sequentially explaining each process (a drilling process, a floor slab splitting process, an edge cutting process, and a lifting process) of the method for removing an existing concrete floor slab according to the first embodiment of the present invention, the first embodiment of the present invention is applied. The effect of the method for removing the existing concrete slab will be described.

  The existing concrete floor slab 12 of the bridge 10 to be removed by applying the method for removing the existing concrete floor slab according to the first embodiment of the present invention has a thickened portion 12A and a general portion 12B as shown in FIG. Do it. The thickened portion 12A of the existing concrete floor slab 12 is located above the upper flange 14A of the existing main girder 14 and close to the existing main girder 14 and the portion adjacent to the upper flange 14A. The thickened portion 12 </ b> A of the existing concrete floor slab 12 is provided so as to protrude downward from the general portion 12 </ b> B of the existing concrete floor slab 12. It is. The general portion 12B of the existing concrete floor slab 12 includes a portion of the existing concrete floor slab 12 that is located between the existing main girders 14 adjacent to each other in the direction perpendicular to the bridge axis and the plate thickness is substantially constant. It is a part above the thickened portion 12A corresponding to a part moved in a direction parallel to the floor slab surface and perpendicular to the bridge axis direction.

(1-1) Drilling Step In the drilling step, the vicinity of the lower end of the thickened portion 12A, which is a portion close to the upper flange 14A of the existing main girder 14 among the portions of the existing concrete floor slab 12, is substantially perpendicular to the bridge axis. A hole drilling portion 20 is provided by drilling in a direction (a substantially horizontal direction and a direction substantially orthogonal to the bridge axis direction). The hole drilling portion 20 is a hole that extends in a substantially horizontal direction and in a direction substantially orthogonal to the bridge axis direction. Of the parts of the existing concrete floor slab 12, the part close to the upper flange 14 </ b> A of the existing main girder 14 (part where the drilling portion 20 is provided) is a thickened part 12 </ b> A of the existing concrete floor slab 12 as shown in FIG. 3. It is a part included in.

  What is necessary is just to determine the magnitude | size (size of an internal diameter) of the drilling part 20 to be provided according to the magnitude | size of the diameter expansion means 40 (refer FIG. 5) to be used, and the pitch of the drilling part 20 to be provided is the diameter expansion to be used. It may be determined in consideration of the magnitude of the force that can be output by the means 40.

  The hole-cutting portion 20 is preferably a through-hole penetrating the thickened portion 12A in a direction substantially perpendicular to the bridge axis in terms of facilitating edge cutting between the existing concrete floor slab 12 and the existing main girder 14, The means 40 can be sufficiently inserted, and by expanding the diameter expanding means 40 in the substantially vertical direction, a sufficient force can be applied to the inner surface of the drilling portion 20 in the substantially vertical direction. If the edge cutting between the existing main girder 12 and the existing main girder 14 can be performed safely, it is not always necessary to use a through hole.

  The hole-drilling part 20 can be provided using a concrete coring tool. In this case, the hole-drilling part 20 is a cylindrical hole. As shown in FIGS. 2 to 5, in the present embodiment, the drilling portion 20 is a cylindrical through-hole, but the shape of the drilling portion 20 is not limited to a cylindrical shape, for example, a polygonal column-shaped hole It may be.

  In addition, it is possible to smoothly perform edge cutting between the existing concrete floor slab 12 and the existing main girder 14 in the edge cutting process described later, and it is possible to smoothly lift the existing concrete floor slab 12 in the lifting process described later. In view of the above, it is preferable to check the position of the stopper 24 melted on the upper surface of the upper flange 14 </ b> A in advance, and to provide the holed portion 20 so as to cut the stopper 24.

(1-2) Floor slab dividing step If necessary, the existing concrete floor slab 12 to be removed is made with a concrete cutter or the like so that the width in the bridge axis direction becomes a predetermined width (a width that can be easily lifted by the lifting means 50). The existing concrete floor slab 12 is cut in a direction perpendicular to the bridge axis to provide a vertical cut surface 30 (see FIG. 4) and divided in the bridge axis direction.

  Further, when the existing concrete floor slab 12 to be removed becomes too heavy and cannot be lifted safely by the lifting means 50, the ground cover 16 and the rail 18 are cut and lifted by using, for example, a wire sawing method or the like. The weight of the existing concrete floor slab 12 that is lifted by the means 50 is reduced to a weight that can be lifted safely.

  It should be noted that the floor slab splitting process is a process performed according to the capacity of the lifting means 50, the situation of the removal site, etc., and normally the floor slab splitting process is performed, but the existing concrete floor slab 12 can be removed without splitting. As long as the existing concrete floor slab 12 can be safely lifted and removed by the lifting means 50, the floor slab dividing step may be omitted.

(1-3) Edge Cutting Process In the edge cutting process, first, the diameter expanding means 40 is inserted into the hole drilling portion 20. When the diameter expanding means 40 is inserted, the diameter increasing direction of the diameter expanding means 40 is set to be substantially vertical. The diameter expanding means 40 is indicated by a two-dot chain line in FIG.

  After inserting the diameter-expanding means 40 at a predetermined position of the hole-drilling part 20, the diameter-expansion means 40 is enlarged in the substantially vertical direction, and a force 42 in the substantially vertical direction is applied to the inner surface of the hole-drilling part 20, Edge cutting between the concrete floor slab 12 and the existing main girder 14 is performed. In FIG. 4 and FIG. 5, the substantially vertical force 42 is schematically represented by an arrow starting from the inner surface of the hole drilling portion 20.

  However, from the viewpoint of safety, it is desirable that the existing concrete floor slab 12 be supported by the lifting means 50 such as a crane before the diameter expanding means 40 is expanded in the substantially vertical direction and the edge cutting is performed. .

  The diameter expansion means 40 to be used is a size that can be inserted into the hole drilling portion 20 and can sufficiently apply a force to the inner surface of the hole drilling portion 20 in a substantially vertical direction. Any material can be used as long as it can safely cut the edge with the main beam 14.

  Specifically, for example, a hydraulic-type arrow or a blow-type arrow can be used. When using a hydraulic sliding arrow, noise hardly occurs in the edge cutting process, so when applying the existing concrete floor slab removal method according to this embodiment to an urban bridge, Is preferably used. In addition, even when a striking-type arrow is used, the amount of noise generated is smaller than that of a conventional technique (for example, the technique described in Patent Document 2).

  The hole drilling portion 20 is provided in the thickened portion 12A of the existing concrete floor slab 12 and is not provided in the existing main girder 14. For this reason, the gap (edge cutting portion 22) generated when the diameter expanding means 40 inserted into the hole drilling portion 20 is expanded in the vertical direction and the existing concrete floor slab 12 and the existing main girder 14 are edge-cut is not provided. Since it occurs in the thickened portion 12A of the concrete slab 12 or at the boundary between the thickened portion 12A of the existing concrete slab 12 and the upper flange 14A of the existing main girder 14, the existing main girder in either case It is almost impossible to damage 14.

  The upper surface 14A of the upper flange 14A of the existing main girder 14 is melted with a stopper 24 such as a slab anchor or a stud gibber. Therefore, even if the existing concrete floor slab 12 and the existing main girder 14 are trimmed, It may be assumed that the existing concrete floor slab 12 cannot be lifted safely only by lifting with the lifting means 50.

  In order to avoid this, before lifting the existing concrete slab 12 (before the lifting process), a cutting process for cutting the stopper 24 from the gap (edge cutting part 22) generated by the edge cutting process is performed as necessary. It is preferable to provide them. When cutting the stopper 24 from the edge cut portion 22, for example, a cutting means such as gas cutting can be used.

(1-4) Lifting step In the lifting step, the existing concrete floor slab 12 that has been edge-cut with the existing main girder 14 in the edge-cutting step is lifted upward by the lifting means 50 and loaded onto a transport truck or the like.

  The lifting means 50 is not particularly limited as long as it can safely lift the existing concrete slab 12 that has been edge-cut with the existing main girder 14, and for example, a crane or the like can be used.

  The pavement 80 laid on the upper surface of the existing concrete floor slab 12 is lifted together with the existing concrete floor slab 12 and removed.

  However, there is a possibility that a small piece of concrete may remain on the upper surface of the upper flange 14A of the existing main girder 14 after the existing concrete floor slab 12 is removed. In this case, it remains on the upper surface of the upper flange 14A of the existing main girder 14. Remove concrete pieces manually. This manual removal or the like can be easily performed by hand using a concrete breaker or the like, which has been conventionally required, and can be completed in a considerably short work time.

  Even if a concrete piece remains on the upper surface of the upper flange 14A of the existing main girder 14 after the existing concrete slab 12 is removed, from the viewpoint of reducing the amount of the concrete piece, the upper surface of the upper flange 14A of the existing main girder 14 can be as much as possible. It is preferable to provide the drilling portion 20 at a close position. On the other hand, if the hole drilling portion 20 is provided as close as possible to the upper surface of the upper flange 14A of the existing main girder 14, the possibility of damaging the upper flange 14A of the existing main girder 14 in the drilling process increases. It is necessary to pay close attention to.

  Further, the stoppers such as stud gibber and anchor bars remaining on the upper surface of the upper flange 14A of the existing main girder 14 are cut and removed with a gas cutter or the like.

(1-5) Effect In the method for removing an existing concrete floor slab according to the first embodiment of the present invention, the diameter expanding means 40 is inserted into the hole drilling portion 20 provided in the hole drilling step so as to increase the diameter substantially in the vertical direction. In addition, since a substantially vertical force 42 is applied to the inner surface of the hole drilling portion 20 to cut the edge between the existing concrete floor slab 12 and the existing main girder 14, the existing concrete floor slab is used as in a conventional general removal method. The edge of the existing concrete slab 12 and the existing main girder 14 is cut without cutting 12 in the bridge axis direction (without providing a vertical cutting surface extending in the bridge axis direction). For this reason, in the removal method of the existing concrete floor slab according to the first embodiment of the present invention, the existing concrete floor slab 12 remains in an integrated state in the direction perpendicular to the bridge axis (the existing concrete floor slab 12 is positioned above the upper flange 14A of the existing main girder 14). The existing concrete floor slab 12 can be lifted by the lifting means 50 and removed. The pavement 80 can also be removed together with the existing concrete floor slab 12 while being laid on the upper surface of the existing concrete floor slab 12.

  For this reason, in the removal method of the existing concrete floor slab which concerns on 1st Embodiment of this invention, the location (location which forms a vertical cut surface) which cuts the existing concrete floor slab 12 can be reduced, and the existing main Work to remove the part of the existing concrete floor slab 12 located above the girder 14 by hand is not necessary, or even if manual work is required, it can be completed in a significantly shorter work time than before. can do.

  Further, the gap (edge cutting portion 22) generated by the edge cutting process occurs in the thickened portion 12A of the existing concrete floor slab 12, or between the thickened portion 12A of the existing concrete floor slab 12 and the upper flange 14A of the existing main girder 14. Since it occurs at the boundary, it is unlikely that the existing main girder 14 will be damaged when the existing concrete floor slab 12 and the existing main girder 14 are trimmed.

  Therefore, by using the existing concrete floor slab removal method according to the first embodiment of the present invention, when removing the existing concrete floor slab, the work on the bridge surface can be reduced without cutting the existing main girder. And noise during removal can be suppressed.

  Since the work time on the bridge surface when removing the existing concrete floor slab can be shortened, the existing concrete floor slab removal method according to the first embodiment of the present invention is used when replacing the bridge floor slab. As a result, the time for traffic regulation can be shortened.

(2) 2nd Embodiment Although the removal method of the existing concrete floor slab which concerns on 2nd Embodiment of this invention is demonstrated, the object of the code | symbol attached | subjected by description of the removal method of the existing concrete floor slab which concerns on 1st Embodiment The same reference numerals are used for the same objects, and description thereof is omitted.

  In the method for removing the existing concrete floor slab according to the second embodiment of the present invention, the upper flange 14A of the existing main girder 14 among the parts of the existing concrete floor slab 12 is provided before the drilling step of providing the drilling portion 20. A cutting step is provided in the vicinity of the lower end portion of the thickened portion 12A, which is an adjacent portion, in which a cut 60 is provided in a direction substantially perpendicular to the bridge axis (in a substantially horizontal direction and substantially perpendicular to the bridge axis direction). . In this cutting step, the cut line 60 is provided in a substantially horizontal direction and at a depth of about 10 cm in a direction substantially orthogonal to the bridge axis direction, and is provided so as to extend in the bridge axis direction. Of the parts of the existing concrete floor slab 12, a part close to the upper flange 14A of the existing main girder 14 (part where the cut 60 is provided) is included in the thickened portion 12A of the existing concrete floor slab 12, as shown in FIG. It is a site.

  The cut 60 can be provided by using a wall saw 64 of a cutting machine 62 as shown in FIG. The cutting machine 62 can be attached to the existing main girder 14. Specifically, for example, the cutting machine 62 may be attached to the vertical stiffener 14 B of the existing main girder 14.

  In the removal method of the existing concrete floor slab according to the second embodiment, as shown in FIG. 7 (A), after a cut 60 is provided in the thickened portion 12A of the existing concrete floor slab 12 by a wall saw 64 or the like. As shown in FIG. 7 (B), the hole drilling portion 20 is provided in the thickened portion 12A of the existing concrete floor slab 12 so as to include at least a part of the cut 60. Then, as shown in FIG. 7 (C), the diameter expanding means 40 is inserted into the hole drilling portion 20 to expand the diameter expanding means 40 in the substantially vertical direction, and the inner surface of the hole drilling portion 20 is substantially vertical. Then, the edge of the existing concrete floor slab 12 and the existing main girder 14 is cut. In FIG. 7C, reference numeral 70 indicates a crack generated by performing edge cutting as described above.

  In the removal method of the existing concrete floor slab according to the second embodiment, not only the hole drilling portion 20 but also the cut 60 is provided in the vicinity of the lower end portion of the thickened portion 12A. When the diameter means 40 is expanded in a substantially vertical direction and a force 42 in a substantially vertical direction is applied to the inner surface of the hole drilling portion 20 to perform the edge cutting between the existing concrete floor slab 12 and the existing main girder 14, the edge cutting is smooth. It is easy to progress. The cut 60 is the leading edge of the edge cutting between the existing concrete floor slab 12 and the existing main girder 14.

  In the removal method of the existing concrete floor slab according to the second embodiment, the existing concrete floor slab according to the first embodiment is provided except that a cutting process for providing the cut 60 is additionally provided before the drilling process. Since it is the same as the removal method of, overlapping explanation is omitted.

(3) Third Embodiment A method for removing an existing concrete floor slab according to a third embodiment of the present invention will be described. Reference numerals attached in the description of the method for removing an existing concrete floor slab according to the first and second embodiments The same reference numerals are used for the same objects as the objects of and the description is omitted.

  In the removal method of the existing concrete floor slab according to the second embodiment of the present invention, the cutting step of providing the cut 60 is performed before the drilling step of providing the drilling portion 20, but in the third embodiment of the present invention. In the method for removing the existing concrete slab, the cutting process for providing the cut 60 is performed after the drilling process for providing the hole drilling part 20.

  In the removal method of the existing concrete floor slab according to the third embodiment, first, the existing main girder 14 among the parts of the existing concrete floor slab 12 is removed in the same manner as the removal method of the existing concrete floor slab according to the first embodiment. The vicinity of the lower end of the thickened portion 12A, which is a part close to the upper flange 14A, is drilled in a direction substantially perpendicular to the bridge axis (a direction substantially horizontal and a direction substantially perpendicular to the bridge axis direction). A hole 20 is provided. And in the site | part which adjoins the upper flange 14A of the existing main girder 14 among the site | parts of the existing concrete floor slab 12 so that at least one part of the provided drilling part 20 may be included, it is a substantially bridge axis orthogonal direction (substantially horizontal direction). In addition, the cut line 60 is provided in a direction substantially perpendicular to the bridge axis direction.

  In the removal method of the existing concrete floor slab according to the third embodiment, the process after the cut 60 is provided is the same as the removal method of the existing concrete floor slab according to the second embodiment. Omitted.

DESCRIPTION OF SYMBOLS 10,100 ... Bridge 12,102 ... Existing concrete floor slab 12A ... Thickening part 12B ... General part 12C ... Haunch part 14, 104 ... Existing main girder 14A, 104A ... Upper flange 14B ... Vertical stiffener 16 ... Ground cover 18 DESCRIPTION OF SYMBOLS 20 ... Drilling part 22 ... Edge cutting part 24 ... Shifting prevention 30, 120 ... Vertical cutting surface 40 ... Diameter expanding means 42 ... Force in substantially vertical direction 50, 200 ... Lifting means 60 ... Cut 62 ... Cutting machine 64 ... Wall So 70 ... Crack 80 ... Pavement

Claims (3)

Of the site of existing concrete slab, at a site close to the flange on the existing main beam, and a generally horizontal direction, and is provided with a drilling unit which penetrates by drilling in a direction perpendicular to the bridge axis direction substantially Drilling process,
By inserting a diameter expanding means for expanding the diameter of the hole in a substantially vertical direction into the hole provided in the hole drilling step, and expanding the diameter of the diameter expanding means in a substantially vertical direction, An edge cutting step of applying an upward and downward force from the inner surface of the existing concrete floor slab and the existing main girder,
A cutting step of cutting the slip stopper that has been fused to the upper flange of the existing main girder, from the gap generated by the edge cutting in the edge cutting step,
After the cutting step, we have a, and lifting upward lifting process the existing concrete slab that is the edge cutting of the existing main beam,
Prior to the edge cutting step, a step of forming a cut formed in a direction substantially perpendicular to the bridge axis extending in the bridge axis direction with respect to a part of the existing concrete floor slab adjacent to the upper flange of the existing main girder. A method for removing an existing concrete floor slab characterized by not including The existing concrete floor slab has a haunch portion that increases in thickness as it approaches the existing main girder, and is located above the upper flange of the existing main girder among the parts of the existing concrete floor slab. removing method of the existing concrete slab according to claim 1, characterized in that providing the drilling unit to the increasing thickness portion consisting of sites and the haunch portions close to the upper flange. Said upset section, Ri hydraulic parsley arrows or striking expression parsley Yadea, wherein in cutting step, according to claim 1 or 2, characterized in that cutting the displacement preventing the gas existing concrete slab Removal method.