JP2021179149A - Assembly structure for placing roadbed concrete, concrete press-in machine and roadbed concrete placing method - Google Patents

Abstract

To provide an assembly structure for placing roadbed concrete which resolves the problem of quality deterioration, defects, construction loss, etc., due to the finishing of a slope when placing roadbed concrete to construct it as an RC structure with the slope such as a roadbed surface of a highway ramp or a channel surface of a sub-bank of a dam.SOLUTION: A roadbed reinforcing bar is configured by upper and lower bars whose direction of either a vertical or horizontal steel bar roughly matches a direction of a drainage slope on an upper surface of a roadbed, and a substantially gate-type or rod-type stirrup reinforcement that restrains both upper and lower bars, and a net body structure is configured by a plurality of elongated belt-like net bodies having one or more planes; an axial direction of the net body is made approximately orthogonal to a direction of the drainage slope in a narrow space between the upper and lower bars; at least one plane of the net body is placed facing an approximately vertical portion of the stirrup reinforcement or a lower surface of the upper bar; and at least one end of the plane of the net body in a cross-sectional view is arranged in a slope portion in a direction of the drainage slope in a vertical cross-sectional view facing the lower surface of the upper bar.SELECTED DRAWING: Figure 3

Description

The present invention relates to an assembly structure for placing a roadbed concrete having a slope, particularly an arrangement structure of a net body for restraining the roadbed concrete, a concrete press-fitting device for that purpose, and a method for placing the roadbed concrete.

Concrete structures have a long history and have been put into practical use since ancient Roman times. However, RC (Reinforced Concrete) structures, which are reinforced by inserting reinforcing bars, appeared in the 19th century. In general, RC structures have a structural analysis of bending fracture and shear fracture, which are typical fracture forms, in the integrated structure of concrete, which is strong in compression and weak in tension, and vice versa. And design for the compression load of concrete.

For this reason, fine aggregate and coarse aggregate are evenly dispersed in the cement paste so that the reinforcing bars and concrete are densely integrated without causing junkers, and each finished surface is compacted so that it is the same as the design drawing. It is stipulated in the concrete standard specifications that it must be finished.

The procedure for placing concrete in an RC structure will be described with reference to the tool shown in FIG.
The hose 81 from the pump truck is moved to fill the concrete in every corner of the formwork, and the concrete is uniformly compacted by the vibrator 82 so that the junker does not come out. Then, the surface is roughly finished with a wooden trowel 83 or a dragonfly 84.

After that, it breathes as the aggregate and cement settle, and after excess water is exposed on the surface, it is tamped with a tamper (human-powered tamper 85, engine tamper 86).

Furthermore, the excess water exposed on the surface is dissipated by reabsorption or evaporation of the hydration reaction, and the surface is gradually crimped with a trowel 88 or Trowel 89 in a short time until the start of condensation. Finish the trowel smoothly while increasing the amount of water.

As described above, the concrete placement of the RC structure is usually performed in the order of filling / compaction, rough finishing, tamping and final finishing. Further, the RC structure is generally designed on the premise that it is composed of a surface to be troweled and a vertical surface held by a formwork due to such construction restrictions.

Deterioration of the RC structure will be described with reference to FIG. FIG. 10 is a diagram showing the deterioration mechanism and the effect of tamping.
Deterioration of the RC structure starts from the surface of the covering portion 11 of the reinforcing bar. Deterioration factors 12 that invade from the surface include chloride ions, carbon dioxide, oxygen, and water. In addition to the type of cement and the water absorption rate of the aggregate, the state of the voids in the covered portion 11 of the reinforcing bar 16, that is, the denseness, influences the factors that determine the penetration rate. The progress of rusting of the reinforcing bar after the invasion of the deterioration factor 12 is affected by the state of adhesion between the reinforcing bar and the concrete, that is, the solidity (see the figure on the right side of FIG. 10).

The vertical surface held in the formwork is determined by the quality of the concrete and the quality of the compaction, which determines the compactness, solidity and durability. However, since the surface to be troweled does not have a formwork, in addition to this, the fineness, the solidity and the durability are influenced by the quality of the tamping after the rough finishing and the final finishing (FIG. 9). This is because, in part, concrete has different degrees of sedimentation and shrinkage of aggregates and cements until the concrete starts to condense in places where the reinforcing bars are restrained and where they are not restrained after filling. .. The other reason is that the water streaks 15 that serve as a water escape route due to breathing are less dense (see the figure on the left side of FIG. 10).

That is, if tamping is omitted, cracks 13 directly above the reinforcing bar and voids 14 directly below the reinforcing bar remain after rough finishing, and the covering portion 11 of the reinforcing bar 16 cannot be densified and the reinforcing bar 16 itself cannot be made dense with concrete. (See the figure on the left side of FIG. 10). If the concrete is soft, use a lightweight and wide trowel such as a wooden trowel 83 to finish it softly. Then, in a state where the concrete from the time when the excess water exposed on the surface is dissipated to the first condensation is hardened, the concrete is gradually and strongly crimped with a trowel 88 to finish (see FIG. 9). As a result, the densification of the covered portion 11 of the reinforcing bar 16 can be effectively enhanced.

In short, tamping and gradual trowel finishing not only finish the surface flat, but also dissipate cracks 13 directly above the reinforcing bar and voids 14 directly below the reinforcing bar due to the reinforcing bar, and the denseness and denseness of the covering part that protects the reinforcing bar. The purpose is to improve the actuality. In addition, if the timing of tamping and stepwise trowel finishing for breathing and the onset of condensation is incorrect, the covered part of the reinforcing bar may become vulnerable rather than densified or solidified.

On the other hand, RC structures in social infrastructure may be required to finish with a gradient of more than 7 degrees due to their function. For example, it corresponds to the case of an RC structure having a slope such as "the roadbed surface of a highway ramp" or "the waterway surface of a sub-bank of a dam".

In the filling, compaction, rough finishing, tamping, and final finishing of roadbed concrete with these gradients, the concrete filled with the pump becomes locally horizontal when compacted with a vibrator, and the finishing gradient is adjusted. I can't keep it. In addition, as a whole, lateral flow accompanied by arc slip may occur, and the finished surface may be raised downward and depressed upward.

Therefore, even if it is compacted after filling, it is necessary to manually scrape it up in the subsequent rough finishing, and it cannot be sufficiently compacted. After that, when tamping is performed, the concrete having thixotropic property re-fluidizes and locally hangs down, the finish gradient cannot be maintained, and lateral flow accompanied by arc slip may occur as a whole. For this reason, there is a problem that the denseness, solidity, and durability of the covered portion of the reinforcing bar and the periphery of the reinforcing bar cannot be ensured (see "Problems of the conventional construction method" shown in FIG. 19).

Japanese Unexamined Patent Publication No. 9-67890 Japanese Unexamined Patent Publication No. 2000-38839 Japanese Unexamined Patent Publication No. 2002-309699 Japanese Patent No. 6621441

Next, the prior art will be explained.
The technique described in Patent Document 1 utilizes a wire mesh on the surface of concrete to be cast, and relates to a method for finishing a thin layer of steep concrete such as a roof in the field of construction. A hexagonal wire mesh is placed on the surface of the reinforcing bar, the lower part of the hexagonal wire mesh is filled first, and then the upper part of the hexagonal wire mesh is finished. Despite the steep slope, it is a suitable construction method for solving concrete dripping.

However, in the case of a steep "highway ramp roadbed surface" or "dam sub-bank waterway surface", the concrete layer is thick, so there are the following problems.
1) Since the lifting pressure of concrete is applied to the lower part of the hexagonal wire mesh when filling it, the position of the reinforcing bar that peels off or is fixed is displaced.
2) If there is a metal fitting such as a wall reinforcement or a mechanical foundation on the surface of the reinforcing bar, the hexagonal wire mesh cannot be placed.

3) The hexagonal wire mesh has low rigidity and requires frequent fixing to the reinforcing bar to prevent it from peeling off, which makes the construction complicated.
4) The hexagonal wire mesh prevents the local sagging of the concrete in the lower part to be restrained, but it is difficult to prevent the lateral flow accompanied by the overall arc slip because it is not rigid.

5) Since there is no restraint on the upper finish of the hexagonal wire mesh, it is still not possible to prevent sagging, and the problem of poor quality remains.
6) Since the hexagonal wire mesh is placed on the covering part of the reinforcing bar, it becomes a foreign substance, which promotes the invasion of deterioration factors such as chloride ion, carbon dioxide, oxygen, and water from the surface, and impairs durability.

7) When the hexagonal wire mesh is placed, it cannot be compacted by a vibrator, so that it is not possible to remove cracks directly above the reinforcing bars and voids directly below the reinforcing bars due to breathing and sedimentation of aggregates and cement.
8) Due to the steep slope finishing technology of thin layers, if the concrete layer is thick, such as "roadbed surface of highway ramp" or "waterway surface of sub-bank of dam", it is caused by the chixotropy of concrete. It cannot correspond to the dynamic behavior.

As described above, the technique described in Patent Document 1 is a technique for utilizing the mesh body on the surface, and the techniques described in Patent Document 2 and Patent Document 3 are techniques for utilizing the mesh body on the side surface. (See FIG. 1 of Patent Document 2 and FIG. 1 of Patent Document 3). In short, conventionally, in a general RC structure, the reticular formation is usually not utilized except for the outer surface utilization.

On the other hand, the technique described in Patent Document 4 relates to a vehicle-mounted mobile formwork device that finishes the surface of concrete to be cast on a steep slope. This is a technique related to a so-called expensive concrete finisher that follows a change in gradient by mechanically changing the angle of the surface formwork (see FIG. 9 of Patent Document 4).

Based on the above, when constructing an RC structure with a gradient, such as "roadbed surface of a highway ramp" or "waterway surface of a sub-bank of a dam", the problems required for finishing the gradient are listed.

1) When there is a gradient, the filled concrete becomes locally horizontal when compacted by a vibrator, and the gradient cannot be maintained. Therefore, it is necessary to manually scoop up each time it is compacted. Then, the reinforcing bar and the concrete cannot be integrated tightly, and the aggregate is not uniformly dispersed in the cement paste, so that the quality is deteriorated.

2) When the slump is about 15 cm with a steep slope exceeding 7 degrees, when the filled concrete is compacted by a vibrator, it causes lateral flow with arc slip as a whole, so it is upward on the finished surface. Settles and rises below. Fearing this situation, it cannot be compacted sufficiently, which causes a defect in compaction.

3) The degree of sedimentation and shrinkage of aggregates and cement differs between the part where the reinforcing bar is restrained after filling the concrete and the part where it is not restrained until the concrete starts to condense. Therefore, if tamping is omitted, cracks directly above the reinforcing bar and voids directly below the reinforcing bar remain. However, in the case of a steep slope, when tamping is performed, the thixotropic concrete refluidizes and the slope cannot be maintained. Therefore, cracks directly above the reinforcing bar and voids directly below the reinforcing bar remain, and the quality of the covered portion of the reinforcing bar deteriorates.

4) If there is a gradient, the final finish with a trowel will be performed without sufficient tamping, so there is only a meaning of ensuring smoothness, and the covered portion of the reinforcing bar is not densified. Then, chloride ions, carbon dioxide, oxygen, water, etc. are easily allowed to enter, which leads to deterioration of the RC structure starting from the surface of the covered portion of the reinforcing bar. For this reason, the rust of the reinforcing bar is promoted and the durability is impaired.

5) In the case of a steep slope, the surface finish can be improved by using hardened concrete with a slump of about 8 cm or expensive thickening concrete mixed with an admixture that imparts viscosity. However, even with such concrete, the fundamental problem of lateral flow accompanied by arc slip due to compaction due to thixotropy is not essentially solved. Further, the thickened concrete has a problem that the pumping property is poor and the concrete is easily closed, so that the construction loss becomes large.

6) If a concrete finisher were to be developed to mechanically solve the problem of finishing the slope, it would be necessary to develop it individually for the shape of each structure, so the period and cost required for the development would be. It is enormous and impractical (see FIG. 9 of Patent Document 3).

7) Concrete is a viscoelastic body containing fine bubbles having a bubble diameter of about 25 to 250 μm due to the surface-activating action of the AE water reducing agent. When these fine bubbles receive a compressive force as a whole, they elastically deform and contract while containing energy. Therefore, at the time of filling, if the lid is put on the entire surface and sealed at a predetermined pressure, the sedimentation and contraction due to breathing can be offset by the elastic effect that continues until the start of condensation, and cracks directly above the reinforcing bar and voids directly below the reinforcing bar do not occur. .. However, if the lid is put on, the quality deteriorates because it cannot be compacted by a vibrator.

On the other hand, the above-mentioned problem in constructing an RC structure that requires a gradient finish is solved by the method described in Patent Document 1 in which a net body is arranged over the entire surface of the upper reinforcing bar of the reinforcing bar and the inside is filled. List the issues.

8) When the lower part of the reticular formation is filled, the lifting pressure of the concrete is predominantly peeled off, or the position of the upper streaks to be fixed is displaced.
9) When the lower inside is filled, the net is filled in one direction from one upper side, the filling path is long, the aggregate is separated, and only the cement paste precedes. Therefore, uniform concrete cannot be placed.

10) If there is a metal fitting for fixing a rising reinforcing bar such as a wall reinforcing bar or a mechanical foundation on the surface of the upper reinforcing bar of the reinforcing bar, the net body cannot be arranged.
11) Since the net body has no rigidity and it is necessary to fix the reinforcing bars at frequent points, the construction becomes complicated.

12) Since there is nothing to restrain the net in the upper finish, the problem of sagging and the problem of poor quality associated with it still remain.
13) Since the reticular formation is placed on the covering part of the reinforcing bar, it becomes a foreign substance, and the invasion of deterioration factors such as chloride ions, carbon dioxide, oxygen, and water from the surface of the covering part is increased, and the durability is impaired. ..

14) Regarding the utilization of reticular formation in RC structures that require a gradient finish, there have been no examples in the past other than superficial utilization. In addition, the analysis of factors of quality deterioration in the finishing of gradients and the mechanical behavior of concrete associated with filling, compaction, and tamping have not been clarified.

Further, in the case where the above-mentioned problem in constructing an RC structure that requires a gradient finish is solved by a method of assembling a steel formwork on the side and the upper part of the entire RC structure and filling the inside. List the issues.
15) Since the vibrator cannot be used, compaction is not required, but expensive non-breathing type high-fluidity concrete is required, which increases the construction cost.

16) Assembling and disassembling the steel formwork composed of the side part and the upper part becomes complicated, so that the construction period is delayed.
17) If there is a metal fitting for fixing a rising reinforcing bar such as a wall bar or a mechanical foundation on the surface of the upper bar, it cannot be covered with a steel formwork from above.

Further, the problems in constructing the RC structure that requires the finish of the above-mentioned gradient will be listed, and the problems in the case of solving the problem by the method of precasting and assembling the entire RC structure will be listed.
18) Since the transportation cost (freight) is higher than the construction method by casting on site, the construction cost will be increased.

19) Since most of the precast method deviates from the conventional design concept, new agreements between the orderer and the contractor are made in terms of design responsibility and product responsibility, which is complicated.
20) The precast members used are limited in terms of transport weight, so the applicable sites are limited.

In order to solve the above problems, as an assembly structure for placing roadbed concrete, the present invention presents the present invention in that the direction of the surface formed by the linear first vertical and horizontal steel bars assembled in a general grid pattern is the direction of the upper surface of the roadbed concrete. A first vertical and horizontal arrangement in which the direction of any of the first vertical and horizontal steel bars is approximately orthogonal to the direction of the water gradient of the upper surface and is arranged with a predetermined covering portion from the upper surface. Approximately in the direction of the steel bars in which the direction of the upper bar made of steel bars and one of the linear second vertical and horizontal steel bars assembled in a general grid pattern is approximately orthogonal to the direction of the water gradient of the first vertical and horizontal steel bars. A mode in which a lower bar made of a second vertical and horizontal steel bar, which has a matching structure and is arranged with a predetermined covering portion from the lower surface of the roadbed concrete, and an upper bar and a lower bar are restrained from each other. As a method, one of the first vertical and horizontal steel bars forming the upper bar and the second vertical and horizontal steel bars forming the lower bar is formed into a general gate type or a bar type by having hook portions at both ends of the steel bar. A roadbed reinforcing bar provided with a stirrup bar arranged so as to have a structure of being hooked by the hook portion of the steel bar of No. 3 and a roadbed reinforcing bar.
A strip-shaped strip having a plurality of nets having at least one or more planes, and a shaft of a plurality of nets in a narrow space between a first vertical and horizontal steel bar forming an upper bar and a second vertical and horizontal bar steel forming a lower bar. The direction is approximately orthogonal to the direction of the water gradient, and at least one of the planes of the network faces the approximately vertical steel bar portion of the third steel bar forming the stirrup bar or the first vertical and horizontal directions. One end of a plane that is arranged facing the lower surface of the steel bar and has at least one end of the plane in the cross-sectional view faces the lower surface of the first vertical and horizontal steel bar and is sloped in the vertical cross-sectional view in the direction of the water gradient. It is characterized by being composed of a network structure arranged in a portion.

According to the present invention, the following effects can be obtained.
1) Since the reticular formation faces the lower surface of the upper muscle,
-Since it is restrained by the upper streaks even with the lifting pressure generated during concrete filling, it does not float and peel off.
-There is no problem even if there is a metal fitting to fix a rising reinforcing bar such as a wall reinforcing bar or a mechanical foundation on the surface of the upper reinforcing bar of the roadbed reinforcing bar.
-Since foreign substances such as nets are not placed on the covering part of the reinforcing bar, the invasion of deterioration factors (chloride ion, carbon dioxide, oxygen, moisture, etc.) from the surface of the covering part is minimized, and the durability is improved.
2) Since the axial direction of the strip-shaped slender is approximately orthogonal to the direction of the water gradient of the roadbed, the reticular formation can be included from below at the same time in the cross-sectional view as the concrete filling rises, and misalignment is unlikely to occur.
3) The reticular formation has an axial direction approximately orthogonal to the direction of the water gradient, and is fixed intermittently with a separation in a plan view. For this reason, in the intermittently vacant separation part, the concrete that tends to blow out to the surface from here due to concrete filling is reduced by the arching effect of the coarse aggregate formed between the mesh bodies facing each other with the separation, and is sufficiently tightened. It can be compacted and tamped (see arching effect 77 shown in step 5 of FIG. 17).
4) If a lath net or expanded metal having a cut in a metal plate and a stretched mesh is used as the net body, the transmittance of the cement paste will be increased. Therefore, at the time of tamping, the necessary cement paste is easily supplied upward from the lower part of the net body, so that cracks directly above the reinforcing bar and voids directly below the reinforcing bar are dissipated and the adhesion performance of the reinforcing bar is improved.
5) Galpanic corrosion that occurs between different materials from the reinforcing bars that adhere to each other by using a stainless steel lath net or expanded metal, which is a rust-resistant alloy steel containing chromium or chromium and nickel in iron, as the net body. Minimize (contact corrosion of dissimilar metals).
6) In the case of expanded metal stainless steel specifications by processing and adopting a perforated plate made of fiber reinforced plastic such as FRP (FIber Reinforced PlastIcs) molded into a lattice shape, approximately honeycomb shape or polka dot shape as a net body. While obtaining the same effect as the above, the weight can be further reduced and the installation can be simplified.
7) The holes in the net of the reticular formation include, for example, a circle having a diameter of 30 to 50 mm to the minimum necessary. Then, since the permeation of the coarse aggregate of φ25 to 40 mm is not allowed, the lateral flow can be suppressed, and the small diameter vibrator of φ28 mm penetrates the coarse aggregate and compacts the upper and lower parts integrally. Therefore, it is possible to cast solid and uniform concrete.
8) The above-mentioned effect is "the roadbed surface of the highway ramp" which has a cant gradient regardless of whether it is in the open air or in the tunnel and continuously changes the cross slope positioned at the water gradient of the roadbed surface in the distance direction. The same effect can be obtained on the roadbed surface of the high-speed Shinkansen.
9) Since any of the steel bars that make up the upper and lower bars in a grid pattern is approximately orthogonal to the direction of the water gradient, if a stirrup bar is attached here, the stirrup bar can be easily constructed vertically. Steel bars stand approximately orthogonally to the direction of the water gradient. Therefore, if the reticular formation is arranged facing the approximately vertical steel bars constituting this forested stirrup bar, the reticular formation will be arranged approximately orthogonal to the direction of the water gradient, and the necessary functions as the above-mentioned reticular formation will be facilitated. Can be realized.

FIG. 1 is a diagram showing the structure of each network. FIG. 2 is a diagram showing casting of a roadbed concrete gradient of 5 degrees according to the first embodiment. FIG. 3 is a diagram showing casting of a roadbed concrete gradient of 10 degrees according to the second embodiment. FIG. 4 is a diagram showing the placement of the roadbed concrete with a gradient of 15 degrees according to the third embodiment. FIG. 5 is a diagram showing a part of FIG. 4 enlarged and subsequent steps. FIG. 6 is a diagram showing a reinforcing bar and a reticular formation in which a concrete press-fitting device is installed. FIG. 7 is a diagram showing the structure of a concrete press-fitting device. FIG. 8 is a diagram showing a situation in which a concrete press-fitting device is installed on a reinforcing bar and a mesh body. FIG. 9 is a diagram showing tools used in each stage of roadbed concrete placement classified into each stage of concrete placement. FIG. 10 is a diagram showing the deterioration mechanism and the effect of tamping. FIG. 11 is a diagram showing an overall bar arrangement diagram of the roadbed concrete of the second embodiment. FIG. 12 is an enlarged view of a part of FIG. 11 of the second embodiment. FIG. 13 is a diagram showing an overall formwork diagram of the roadbed concrete of the second embodiment. FIG. 14 is an enlarged view of the vicinity of the anchor steel bar (for fixing the stirrup bar 26 (38)) 68 of FIG. 13 of the second embodiment. FIG. 15 is an enlarged view of the vicinity of the separator steel bar (for fixing the upper bar 31) 69 of FIG. 13 of the second embodiment. FIG. 16 is a diagram showing casting steps 1 to 3 of the second embodiment. FIG. 17 is a diagram showing casting steps 4 to 6 of the second embodiment. FIG. 18 is a diagram showing a planar casting order of the casting steps 1 to 3 of the second embodiment. FIG. 19 is a diagram showing the problems when the casting step of the second embodiment is performed by the conventional method and the effect of the present invention. FIG. 20 is a diagram showing the types of stirrup muscles used in Examples 1 to 3.

Hereinafter, Examples 1 to 3 will be described with reference to the drawings as embodiments for carrying out the present invention.

Construction elements according to the present invention include "assembly structure of roadbed reinforcing bars", "formwork structure", "method of placing roadbed concrete", and "arrangement structure of net body". Its common purpose is to curb lateral flow and provide adequate compaction and tamping.

FIG. 1 is a diagram showing a network body used in Examples 1 to 3. There are three types: I-shaped formation (vertical arrangement) 51, I-shaped formation (horizontal arrangement) 52, and inverted L-shaped formation 53. FIG. 1 shows a front view of each formation and a side surface on the right side thereof. A three-view view is shown below the figure and a plan view below the figure.

The common feature of the three types of reticular formation is that the surface of the member is reticulated, and the cross-sectional view is approximately I-shaped or approximately L-shaped and strip-shaped. It is to be bound and arranged by a binding line facing the lower surface of the upper muscle.

Further, a pump hose insertion hole 76 is opened in the I-shaped reticular formation (horizontal arrangement) 52 (lower view of FIG. 1). This is for receiving the insertion of the guide pipe of the concrete press-fitting device (this will be described later), and may be opened to each side 54 of each net body arranged horizontally, if necessary. .. These are appropriately selected and arranged according to the gradient conditions and construction conditions.

Next, an example of concrete placement when the slope conditions of the roadbed concrete are different will be described with reference to FIGS. 2 to 4.
FIG. 2 is a placement in the case of a roadbed concrete gradient of 5 degrees as Example 1, FIG. 3 is a placement in the case of a roadbed concrete slope of 10 degrees as Example 2, and FIG. 4 is an embodiment. 3 is the placement when the roadbed concrete slope is 15 degrees.

The configurations and effects of "Assembly structure of roadbed reinforcing bars", "Formwork structure" and "Method of placing roadbed concrete", which are common construction elements, will be collectively described with respect to Examples 1 to 3.

In addition, the configuration and effects of the "reticulation arrangement structure", which is an individual construction element, will be described individually for each embodiment. The reason is that the "reticular formation structure" is determined by the magnitude of the lateral fluidity, which is determined by the magnitude of the gradient, in order to reduce the lateral fluidity to the compaction and tamping of the concrete. In practice, the reticular formation and its arrangement structure may be appropriately combined and changed for individual construction conditions such as gradient conditions, compounding conditions, and structural conditions.

Further, the “casting of roadbed concrete with a gradient of 10 degrees” of Example 2 in which the construction elements of the present invention are widely utilized will be described in detail with reference to FIGS. 11 to 19.

First, "assembly structure of roadbed reinforcing bar", which is a common construction element in Examples 1 to 3 (FIGS. 2 to 4), will be described. In addition, about Example 2, FIG. 11 and FIG. 12 are also referred to.
1) Upper muscle 24
The orientation of the vertical and horizontal surfaces of the linear steel bars assembled in a general grid pattern roughly matches the orientation of the roadbed upper surface 1, and the direction of either the vertical or horizontal steel bars is approximately orthogonal to the direction of the water gradient 3 of the roadbed upper surface 1, and the roadbed. A predetermined covering portion 11 is arranged with a space from the upper surface 1. In Examples 1 to 3 shown in FIGS. 2 to 4, the end of the steel bar of the upper bar 24 is hook-shaped, but this end may be bent into a U shape and fixed to the lower bar side. Not (not shown).

2) Lower muscle 25
The orientation of the vertical and horizontal surfaces of the linear steel bars assembled in a general grid pattern roughly matches the direction of the roadbed lower surface 2, the direction of the vertical and horizontal steel bars roughly matches the direction of the vertical and horizontal steel bars of the upper bar 24, and the roadbed lower surface 2 A predetermined covering portion 11 is vacated from the above and arranged. In Examples 1 to 3 shown in FIGS. 2 to 4, the end of the steel bar of the lower bar 25 is hook-shaped, but the end may be bent into a U shape and fixed to the upper bar side. Not (not shown).

3) Stirrup muscle 26
Whether to cover the upper bar 24 and the lower bar 25 in a ∩ (cap) shape so as to restrain both from one to the other in the shape of a steel bar with hooks at both ends. Alternatively, make a ∪ (cup) shape. Further, the central side 26 (37) of the self-gate type steel bar is pressed against one of the steel bars forming the upper bar 24 or the lower bar 25, and the hook portion at the tip is the other one forming the upper bar 24 or the lower bar 25. Place it so that it can be hooked on a steel bar.
Further, the side 37 of the central steel bar of the general gate type is a surface orthogonal to the water gradient and on the higher side of the water gradient of the steel bar in the direction orthogonal to the water gradient of the upper bar 24 (32) and the lower bar 25. Reinforcement is arranged facing the surface.

FIG. 20 is a diagram showing the types of stirrup muscles used in Examples 1 to 3. In the above description, the stirrup bar 26 has the shape of a general gate type steel bar shown on the left side of FIG. 20, but as shown on the right side of FIG. 20. The hook portion 40 at the tip is the upper bar 24 so as to have hook portions at both ends and to restrain both the upper bar 24 and the lower bar 25 from one to the other in the shape 98 of its own bar-shaped steel bar. Alternatively, it may be arranged so as to be hooked on a steel bar forming the lower bar 25. At that time, as the shape of the hook portion, the tip plate type hook portion 99 may be adopted (in the case of the right end in FIG. 20). In the case of this rod-shaped shape, the rigidity of the shear reinforcement is impaired as compared with the case of the general gate type, so that the seismic performance as an RC structure is lowered, but there is an effect that the installation is easy.

4) Reticular formation 51, 52, 53
The elongated axial direction is approximately orthogonal to the direction 3 of the water gradient of the roadbed, and the direction of the water gradient so that at least one end 55 of each of the surfaces 54 faces the lower surface of the upper bar 24 in a cross-sectional view. Arrange with a gradient in the vertical cross-sectional view of 3.
Further, at least the surface to be arranged substantially vertically faces the surface of the side 26 (38) on both sides of the stirrup bar 26 on the higher side of the water gradient of the steel bar.

Next, the effect of this "assembly structure of roadbed reinforcing bars" will be described.
When the stirrup bar 26 is arranged as in 3) above, a net body facing the upper surface of the water gradient of the steel bar on both sides 26 (38) of the general gate type of the stirrup bar 26. However, each lateral pressure of the concrete received on the higher surface is smoothly transmitted to the upper bar 24 and the lower bar 25 through each stirrup bar 26 without depending on the binding strength of the binding point of the stirrup bar 26. Therefore, the binding points of the reinforcing bars do not shift or come off.

Next, the configuration of the "formwork structure", which is a common construction element in Examples 1 to 3 (FIGS. 2 to 4), will be described. In addition, about Example 2, FIGS. 13 to 15 are also referred to.

The side formwork 61 arranged on both sides of the high side 4 and the low side 5 of the roadbed concrete has the back surface of the horizontal end thick material 62 further holding the vertical end thick material 63 holding the control panel 60 in the direction 3 of the water gradient. It is fixed by the box metal fittings 65 at both ends of the separator steel bar (for penetration) 64 that penetrates.

Next, the effect of this "formwork structure" will be described.
For example, in the case of continuously changing the cross slope positioned in the water gradient of the roadbed surface in the distance direction, as in the case of "roadbed surface of a highway ramp", the direction 3 of the water gradient becomes the short side. The separator steel bar (for penetration) 64 that penetrates in the direction can be short and can be assembled efficiently and firmly.

Further, since the side formwork 61 arranges the horizontal end thick material 62 on the back surface of the vertical end thick material 63, the horizontal end thick material 62 is in the distance direction on the back surface of the vertical end thick material 63 integrated with the control panel 60. Since it can take a long length, it can be assembled efficiently.

Next, the configuration of the "roadbed concrete placing method", which is a common construction element in Examples 1 to 3 (FIGS. 2 to 4), will be described. In addition, about Example 2, FIGS. 16 to 18 are also referred to.

Regarding the horizontal casting range 96 on the lower side of the upper bar 24, casting is performed in the order of d to h from the lower side 5 to the higher side 4.
Subsequently, the gradient casting range 97 facing the lower surface side of the upper bar 24 is driven in the order of d to h from the lower side 5 to the higher side 4. At this time, the approximately vertical surface of the I-shaped reticular formation (vertical arrangement) 51 on the lower side 5 of the water gradient or the inverted L-shaped reticular formation 53 and the I-shaped reticular formation (vertical arrangement) 51 on the higher side 4 of the water gradient thereof. Or, in a space narrow with the approximate vertical surface of the inverted L-shaped formation 53, at least the I-shaped network (vertical arrangement) 51 on the lower side 5 or the upper bar 24 of the approximately vertical surface of the inverted L-shaped formation 53. It is placed up to one end facing the lower surface, and is repeatedly placed in a narrow space so as to increase the slope a predetermined number of times.

After that, after the placement of the gradient casting range 97 facing the lower surface side of the upper bar 24 is completed, the casting range including the upper surface side of the remaining upper bar 24 is from the one with the higher water gradient to the finished surface of the roadbed upper surface 1. Place in order to go down the slope.

Here, the concrete is filled from the pump hose 81 and compacted by the vibrator (compacting) 82. The utilization of the concrete press-fitting device 71 shown in FIG. 4 will be described later as a supplementary explanation of the second embodiment.

Next, the effect of this "method of placing roadbed concrete" will be described.
-Since the reticular formation is cast on a gradient from the low 5 to the high 4 up to one end facing the lower surface of the upper bar 24 on the approximately vertical surface, the hydration reaction proceeds in order from the casting location of the low 5 and hardens. Fill it so that it is piled up. Therefore, even in a stepped casting with a head, the lateral flow accompanied by arc slip can be reduced, and each step can be sufficiently compacted.

In the gradient casting range 97 facing the lower surface side of the upper bar 24, in the casting range including the upper surface side of the remaining upper bar 24 after casting from the low 5 to the high 4 up to the upper end of each network. , From the high side 4 to the low side 5 up to the finished surface of the roadbed upper surface 1, finish. For this reason, the kakiage work is eliminated with the placement, and the efficiency and quality are improved.

-The I-shaped reticular formation (horizontal arrangement) 52 or the inverted L-shaped reticular formation 53 installed in advance below the upper bar 24 is a reticular perforated plate such as expanded metal, or in addition to this, a vibrator is inserted. If a hole is arranged, the vibrator can be inserted below this through the mesh of the mesh itself or the insertion hole. Using this vibrator, the concrete is sufficiently compacted downward and upward, improving the quality.

Regarding the gradient casting range 97 facing the lower surface side of the upper bar 24, the approximately vertical surface of the I-shaped reticular formation (vertical arrangement) 51 or the inverted L-shaped reticular formation 53 on the lower side 5 of the water gradient and its water gradient. In a narrow space with the approximately vertical surface of the I-shaped reticular formation (vertical arrangement) 51 or the inverted L-shaped reticular formation 53 on the higher side 4 of the concrete, fibers such as polypropylene are mixed into the concrete. Then, the arching effect of the coarse aggregate of concrete that tends to blow out to the upper surface 1 side of the roadbed can be promoted, and even soft-kneaded concrete can be reliably compacted and tamped.

In addition, concrete mixed with fibers has low water absorption and thixotropic properties, so that it is well entangled in each reticular formation even though it has good pumping properties and is difficult to block, so the side with arc slip. It essentially solves the direction flow. Here, as the fiber, for example, a polypropylene fiber having a fiber diameter of 1.00 mm, a fiber length of 30 mm, and a tensile strength of ^{about 500 N / mm 2} may be mixed with ^{concrete by about 4 kgf / m 3.}

-For finishing the covering portion 11 of the reinforcing bar in the casting range including the upper surface side of the upper reinforcing bar 24, concrete in which a thickener and a fiber such as polypropylene are mixed is placed. Then, the finishing performance can be improved and the problem of sagging and the problem of poor quality associated therewith can be minimized. In this case, since the net can be sufficiently tamped, there is no problem that the fibers protrude from the surface.

Next, with respect to the "arrangement structure of the network", the configurations and effects of Examples 1 to 3 having different gradient conditions will be described individually with reference to FIGS. 2 to 4.

1) Configuration in the case of "casting of roadbed concrete with a gradient of 5 degrees" according to Example 1-The I-shaped reticular formation (vertical arrangement) 51 has an upper bar and a lower bar in an approximately vertical manner. The slender axial direction is approximately orthogonal to the direction 3 of the water gradient of the roadbed in a narrow space with 25. Further, one surface thereof is arranged so as to face one of the steel bars on both sides 38 of the general gate type stirrup bar 26, and at least one end thereof faces the lower surface of the upper bar 24.
-The separated portions 57 of the net body are arranged intermittently in a plan view, and are arranged with a gradient in a vertical cross-sectional view in the direction 3 of the water gradient.

2) Effect in the case of "casting of roadbed concrete with a gradient of 5 degrees" according to Example 1-In the case of a gradient of 5 degrees, although it depends on the construction conditions, concrete has a lateral fluidity close to that of a plastic fluid. In order to behave in a certain manner, the net body is an I-shaped net body (vertical arrangement) 51, and is arranged on the lower surface of the upper bar 24 so that the side surfaces face the steel bars on both sides 38 of the portal shape of the stirrup bar 26. do it. By doing so, each progressive lateral pressure in the lower direction can be individually held by the upper muscle 24 and the lower muscle 25 via the stirrup muscle 26. Therefore, sagging is reduced and tamping is not hindered.
-Since the axial direction of the net body 51 is approximately orthogonal to the direction 3 of the water gradient and a gap is provided to fix the net body intermittently in the horizontal direction, the separated portion 57 of the plan view net body that is open intermittently is the hose 81 of the concrete pump. And as an insertion port for the vibrator 82, it can be filled smoothly and compacted frequently.

3) Configuration in the case of "casting of roadbed concrete with a gradient of 10 degrees" (FIG. 3) according to the second embodiment (the supplementary explanation will be described later for the "reticular formation arrangement structure" shown in FIGS. 11 and 12).
The inverted L-shaped reticular formation 53 has an L-shaped upside down mode in which the narrow axial direction of the upper bar 24 and the lower bar 25 is approximately orthogonal to the direction 3 of the water gradient of the roadbed. Further, one surface thereof is arranged so as to face one of the steel bars on both sides 38 of the general gate type stirrup bar 26, and the remaining one surface faces the lower surface of the upper bar 24.

-The separated portions 57 of the net body are arranged intermittently in a plan view, and are arranged with a gradient in a vertical cross-sectional view in the direction 3 of the water gradient.
-For the steel bars that roughly match the direction 3 of the water gradient of the roadbed of the roadbed of at least a part of the upper grid-like upper bars, the reinforcing bars themselves or the separator steel bars 69 that are fixed along the reinforcing bars are P-con (plastic cones). ) 66 (see FIG. 15), the side form of the high side 4 is penetrated in the direction 3 of the water gradient of the roadbed, and is fixed by the box metal fitting 65 on the back surface thereof.

4) Effect in the case of "casting of roadbed concrete with a gradient of 10 degrees" (Fig. 3) according to Example 2.-In the case of a gradient of 10 degrees, the concrete is on the side with arc slip as a plastic fluid, although it depends on the construction conditions. In order to show the behavior of directional fluidity, the net body is an inverted L-shaped net body 53 to counteract this lifting pressure, so that each surface faces the lower surface of the upper bar 24 and both sides of the stirrup bar 26. Just place it.

Then, each lifting pressure can be held by the weight of all the reinforcing bars including the lower reinforcing bar through each reinforcing bar through the upper surface and the lateral surface of the inverted L-shaped reticular formation 53, so that the lateral flow accompanied by the overall arc slip. Can be effectively suppressed and there is no problem with tamping.

-Furthermore, the general L-shaped formation is more expensive than the general I-shaped formation, but on the other hand, it has higher obstructiveness and rigidity, so that lateral flow accompanied by arc slip can be suppressed more reliably, and the general shape is also general. When arranging the gate-shaped stirrup bar 26 facing the steel bars on both sides, it is sufficient to align the positions and bind and fix the stirrup bar 24 from above, which simplifies the installation.

The upper bar 24 that holds the stirrup bar 26 that receives lateral pressure from the net body is the entire structure because the separator steel bar 69 that is fixed along the line is passed through the side formwork and fixed by the box hardware 65 on the back surface thereof. Does not slip.

5) Configuration in the case of "casting of roadbed concrete gradient of 15 degrees" according to Example 3-The inverted L-shaped reticular formation 53 is referred to as Example 2 ("casting of roadbed concrete gradient of 10 degrees"). Arrange in the same way. Subsequently, the I-shaped reticular formation (horizontal arrangement) 52 is arranged in a horizontal manner so that the elongated axial direction is approximately orthogonal to the direction 3 of the water gradient of the roadbed in the narrow space of the upper and lower bars 25, and the horizontal plane is formed. The inverted L-shaped network 53 is arranged at the separated portion 57 of the network so as to face the lower surface of the upper muscle 24 in a plan view.
-For the steel bars that roughly match the direction 3 of the water gradient of the roadbed of the roadbed of at least a part of the upper grid-like upper bars, the reinforcing bars themselves or the separator steel bars 69 that are fixed along the reinforcing bars are used as P-con 66 (Fig. 15), the side form of the high side 4 is penetrated in the direction 3 of the water gradient of the roadbed, and is fixed by the box metal fitting 65 on the back surface thereof.

-Anchor steel bars 68, which are fixed along the steel bars on both sides 38 of the gate shape of at least a part of the stirrup bars 26, are fixed and fixed to the foundation concrete.
Subsequently, the pump hose 81 is inserted below the upper bar 24 and the concrete is press-fitted by the concrete press-fitting device 71 combined with the I-shaped net body (horizontal arrangement) 52 in which the pump hose insertion hole 76 opens.

-Here, the concrete press-fitting device 71 will be described with reference to FIGS. 5 to 8.
As shown in FIGS. 6 to 8, in the concrete press-fitting device 71, the guide pipe 72 of the pump hose 81 that descends below the grid-shaped upper bar 24, and the guide pipe 72 are approximately rectangular in the grid-shaped upper bar 24. It is composed of a fixed girder 74 composed of at least two rows arranged in the opening and a connecting material 75 having a guide tube 72 sandwiched between the fixed girders 74 to connect the two. Then, as shown in FIGS. 5 and 6, an I-shaped net body 52 having a pump hose insertion hole 76 in advance is arranged laterally below the upper bar 24, and concrete is passed through a guide pipe 72 penetrating the pump hose insertion hole 76. Is press-fitted at a predetermined pressure.

The procedure for using the concrete is to install a concrete press-fitting device 71 in the circular frame shown in the central part of FIG. 4, insert the pump hose 81, press-fit the concrete as shown in the enlarged view on the upper side of FIG. 5, and press-fit the concrete. When is completed, the concrete press-fitting device 71 is removed as shown in the enlarged view on the lower side of FIG.

6) Effect in the case of "casting of roadbed concrete with a gradient of 15 degrees" (Fig. 4) according to Example 3.-In the case of a gradient of 15 degrees, although it depends on the construction conditions, concrete slides in an arc as a liquid fluid. Due to the high lateral fluidity that accompanies it, the lifting pressure also increases. Therefore, as the reticular formation, the inverted L-shaped reticular formation 53 is intermittently arranged with the separated portion 57 of the plan view reticular formation open in the same manner as in the second embodiment, and the I-shaped reticular formation (horizontal arrangement) 52 is arranged at the separated portion. Is arranged in a horizontal manner. If both are arranged over the entire lower surface of the upper bar 24 in order to withstand the lifting pressure and the hydraulic pressure, there is no problem in tamping.

In addition, the concrete pump hose insertion hole 76 is installed in advance at a predetermined position on the horizontal surface of any of the mesh bodies. Further, when the reinforcing bar slides, the entire reinforcing bar may be fixed to the anchor steel bar 68 to be driven downward via the stirrup bar 26.

-The I-shaped reticular formation (horizontal arrangement) 52 that arranges the approximate I-shape on the lower surface of the upper bar 24 is manufactured in a roll shape at the factory, and if this is installed on the lower surface of the upper bar 24 at the site, it is efficiently arranged. can do. Further, the I-shaped reticular formation (horizontal arrangement) is installed facing the lower surface of the upper bar 24 as a three-dimensional T-shaped or M-shaped or W-shaped reticular formation (both not shown) that undulates in a plane. Then, the same effect can be obtained while increasing the rigidity.

The upper bar 24 that holds the stirrup bar 26 that receives lateral pressure from the net body is the entire structure because the separator steel bar 69 that is fixed along the line is passed through the side formwork and fixed by the box hardware 65 on the back surface thereof. Does not slip.

-Since the stirrup bar 26 that holds the upper bar 24 that receives the lifting pressure from the reticular formation is fixed to the anchor steel bar that is fixed to the foundation concrete, it does not rise, so the reinforcing bar does not slide or lift, and the design document. Can be placed accurately based on.

-In concrete placing, as shown in FIG. 10, the settling 17 due to breathing causes cracks 13 directly above the reinforcing bars and voids 14 directly below the reinforcing bars, so the tamping 85 shown in FIG. 9 is indispensable.

However, in the case of an RC structure having a gradient, when compacted by the vibrator 81, lateral flow accompanied by overall arc slip occurs, and the RC structure cannot be sufficiently compacted. Therefore, as described above, the concrete is press-fitted at a predetermined pressure by the concrete press-fitting device 71. Originally, concrete is a viscoelastic body that contains fine bubbles with a bubble diameter of about 25 to 250 μm due to the surface active action of an AE agent or the like. The effect offsets the sedimentation 17 associated with breathing. Therefore, the crack 13 directly above the reinforcing bar and the void 14 directly below the reinforcing bar can be reduced, and the quality can be improved.

-Since the concrete press-fitting device 71 can be easily attached to and detached from the upper bar 24 via the fixed girder 74 or the connecting material 75 by using a rubber band (not shown) having a hook, a plurality of main press-fitting devices are arranged in a row. If the concrete is continuously placed and removed from the bottom to the top with respect to the progress of the placing, the work efficiency can be improved.

-At the time of press-fitting, the reaction force against the lifting pressure applied to the concrete press-fitting device 71 is carried by the weight of the entire reinforcing bar from the rubber band with the hook (not shown) through the upper bar, so the concrete is surely filled with the specified pressure. -It can be compressed, and as described above, the crack 14 directly above the reinforcing bar and the void 14 directly below the reinforcing bar can be reduced, and the quality can be improved.

-The guide pipe 72 of the concrete press-fitting device 71 has a slightly larger diameter than the pump hose 81, and the overall shape is made into a funnel shape, and the pump hose 81 is inserted. As a result, the pump hose 81 can be easily inserted and the mesh body is not damaged, the joint fastening work of the concrete pipe becomes unnecessary, and the work efficiency can be improved.

-When the press-fitting of concrete is completed and the pump hose 81 is pulled out from the guide pipe 72, the pump hose insertion hole 76 is protected by the guide pipe 72, so that the net body is not damaged. Encapsulation can be continued. Therefore, it contributes to offsetting the sedimentation 17 due to breathing, reducing the crack 13 directly above the reinforcing bar and the void 14 directly below the reinforcing bar, and can improve the quality.

Similarly, when the press-fitting of the concrete is completed and the pump hose 81 is pulled out from the guide pipe 72, the concrete sealed at a predetermined pressure is formed in the pump hose insertion hole 76 as shown in the lower figure of FIG. Since it does not spout in the vicinity due to the arching effect 77 of the coarse aggregate, lateral flow accompanied by arc slip can be effectively suppressed.

Next, the "casting of a roadbed concrete gradient of 10 degrees" according to the second embodiment shown in FIG. 3 utilizes the construction elements of the present invention in a wide variety of ways, but the "reticular formation arrangement structure" shown in FIGS. 11 to 15 is used. , A supplementary explanation will be given.

FIG. 3 is a diagram showing only the situation of the inverted L-shaped net 53 on the high side, but on the low side, as shown in the cross-sectional view of FIG. 11, the inverted L-shaped net is the same as in Example 3. The I-shaped reticular formation (horizontal arrangement) 52 is arranged at the separated portion 57 of the plan view reticular formation of the body 53 so that its horizontal plane faces the lower surface of the upper streaks 24.

Here, as described above, as shown in FIG. 15, the steel bars that roughly match the direction 3 of the water gradient of the roadbed of at least a part of the upper bars 24 having a general grid pattern are the reinforcing bars themselves or along the reinforcing bars. The separator steel bar 69 to be fixed is passed through the side formwork of the high side 4 in the direction 3 of the water gradient of the roadbed through the P-con 66, and is fixed by the box metal fitting 65 on the back surface thereof.

Similar to the third embodiment, the anchor steel bar 68 to be fixed along the steel bars on both sides 38 of the gate shape of at least a part of the stirrup bars 26 is fixed and fixed to the foundation concrete as shown in FIG. do.

Here, as the fixing method of each of the above-mentioned separator steel bar 69 fixed along the upper bar 24 and the anchor steel bar 68 fixed along the steel bars 38 on both sides of the portal of the stirrup bar 26. As shown in FIGS. 14 and 15, after inserting both (reinforcing bar and steel bar) into the elliptical tubular caulking material 79 that crimps both, the caulking pin 80 is inserted between them with a hydraulic jig. It may be done by the method of tightening. Further, welding or other methods may be used.

Regarding the concrete press-fitting device 71 used in the third embodiment, as shown in the cross-sectional view and the plan view of FIG. 11, in the second embodiment, the lower side (the portion where the I-shaped reticular formation 52 having the pump hose insertion hole 76 is arranged) is arranged. ).

Next, the effect of the "arrangement structure of the net body" in the case of "casting with a roadbed concrete gradient of 10 degrees" according to the second embodiment will be supplementarily explained with reference to FIGS. 11 to 15.
As described above, the concrete in Example 2 exhibits the behavior of lateral fluidity accompanied by arc slip as a plastic fluid, and at that time, the lateral fluidity is more predominant on the lower side than on the higher side. do.

Therefore, as shown in FIG. 11, the high-level reticular formation is an inverted L-shaped reticular formation 53 in order to counteract this lifting pressure, and faces the lower surface of the upper bar 24 and both sides of the stirrup bar 26. It may be arranged as follows.

On the other hand, the lower reticular formation with predominant lateral fluidity also has a higher lifting pressure than the higher reticular formation, so as shown in FIG. 12, as in the case of Example 3, the inverted L-shaped reticular formation The 53 is intermittently arranged with the separated portion 57 of the plan view network open, and the I-shaped reticular formation (horizontal arrangement) 52 is arranged in the separated portion in a horizontal manner so as to withstand the lifting pressure and the hydraulic pressure. If both are arranged on the lower surface of the upper bar 24, there is no problem in tamping.

Further, as in the case of the third embodiment, the concrete pump hose insertion hole 76 is previously installed at a predetermined position on the substantially horizontal surface of any of the lower net bodies. Further, when the reinforcing bar is lifted, as shown in FIG. 14, the entire reinforcing bar may be fixed to the anchor steel bar 68 to be driven downward via the stirrup bar 26.
As described above, the lateral flow accompanied by the overall arc slip can be effectively suppressed, and the tamping is not hindered.

Further, a method procedure in the case of “casting with a roadbed concrete gradient of 10 degrees” according to the second embodiment will be described for each step shown in FIGS. 16 and 17 with reference to FIGS. 16 to 18. Here, FIG. 16 is a diagram showing Step 1 (Step 1) to Step 3 (Step 3) in Example 2, and FIG. 17 is a diagram and a diagram showing Step 4 (Step 4) to Step 6 (Step 6) in Example 2. 18 is a diagram showing the planar casting order of steps 1 to 3 in the second embodiment.

1) Step 1
The horizontal casting range I is located horizontally below the upper bar 24. Therefore, the pump hose (filling) 81 is used for driving and the vibrator is used for compaction 82 in the order of a to h from the low side 5 to the high side 4. It should be noted that the portion where the I-shaped reticular formation (horizontal arrangement) 52 is obstructed may be locally untied and displaced (not shown).

2) Step 2
The gradient casting range II faces the lower surface side of the upper bar 24. Therefore, in the narrow space between the approximately vertical surface of the low-level network and the approximately vertical surface of the high-level network, the placement is repeated a predetermined number of times so as to increase the gradient, and the low-level side 5 to the high-level side In the order of a to c toward No. 4, the pump hose (filling) 81 is used for driving and the vibrator is used for compaction 82. The vibrator may be inserted below the network by providing a small-diameter insertion hole (not shown) in the network in advance, or by penetrating the mesh of the network itself.

Further, in the gradient casting range II, if only the inverted L-shaped network 53 is arranged, there is a concern about lateral flow accompanied by arc slip in the subsequent tamping. Therefore, in the gradient casting range II, an I-shaped reticular formation (horizontal arrangement) 52 is arranged in addition to the inverted L-shaped reticular formation 53, and concrete is press-fitted by the concrete press-fitting device 71 while suppressing lateral flow. At the same time, compaction 82 is performed by a vibrator. A plurality of concrete press-fitting devices 71 may be installed and continuously displaced (not shown).

3) Step 3
In the horizontal casting range III, the inverted L-shaped reticular formation 53 arranged intermittently is efficiently driven by a pump hose (filling) 81 from the separated portion 57 of the plan view reticular formation, and the compaction 82 by the vibrator is applied. conduct.

4) Step 4
In the casting range IV of the remaining gradient, the pump hose (filling) 81 is used from the separated portion 57 of the plan-viewing network of the inverted L-shaped network 53 arranged intermittently to the approximately vertical surface of the lower network. Pump hoses (pump hoses in the order of d to h from the low side 5 to the high side 4) are repeatedly driven a predetermined number of times so as to increase the gradient in the narrow space with the approximate vertical surface of the high side net. Filling) 81 is used for placing and compaction 82 is performed with a vibrator. The vibrator is also efficiently inserted below the network from the separated portion 57 of the plan view network of the inverted L-shaped network 53.

5) Step 5
The casting range V of the finished surface includes the upper surface side of the remaining upper bar 24. Therefore, in the casting range V of the finished surface, the pump hose (filling) 81 is used for driving, the compaction 82 is performed by a vibrator, and the wood is used so that the slope is lowered in order from the one with the highest water gradient to the finished surface on the upper surface of the roadbed. After rough finishing 83 with a hose, tamping 85 with a human-powered tamper is performed at a predetermined timing.

6) Step 6
The final finishing 88 with a trowel is performed on the casting range V of the finished surface.

Here, the effects other than the effects described above will be supplementarily described with respect to the second embodiment.
As described above, in the second embodiment, the concrete exhibits the behavior of lateral fluidity accompanied by arc slip as a plastic fluid, and the lateral fluidity is further predominant on the lower side as compared with the higher side.

Therefore, on the lower side, an inverted L-shaped reticular formation 53 and an I-shaped reticular formation (horizontal arrangement) 52 are arranged, and the concrete is compacted while being pressed in by the concrete press-fitting device 71 while suppressing the lateral flow. Suppresses lateral flow with arc slip on the lower side.

Further, on the higher side, only the inverted L-shaped reticular formation 53 is intermittently arranged to compact the concrete inexpensively and efficiently, and prevent the concrete from dripping again. Then, it can be sufficiently compacted and tamped.

FIG. 19 is a diagram showing the problems and the effects of the present invention when the casting step of the second embodiment is performed by the conventional method.
The case where steps 2 to 4 (Step 2 to 4) and step 5 (Step 5) of the second embodiment are carried out by the conventional method without countermeasures is compared. In the case of the target gradient of 10 degrees in Example 2, as described above, concrete exhibits the behavior of lateral fluidity 21 accompanied by arc slip as a plastic fluid, but the lower side is compared with the higher side. Further, the lifting pressure 22 is increased and the lateral fluidity 21 is predominant. Therefore, it cannot be sufficiently compacted and tamped. However, according to the present invention, as described above, it is possible to sufficiently compact and tamping.

1 Roadbed upper surface, 2 Roadbed lower surface, 3 Water gradient direction, 4 High side, 5 Low side,
11 Covered part, 12 Deterioration factor, 13 Crack just above the reinforcing bar, 14 Void just below the reinforcing bar,
15 water bars, 16 rebars, 17 breathing subsidence, 20 rebar sliding,
21 lateral flow (arc slip), 22 lifting pressure, 23 reaction force, 24 upper bar, 25 lower bar,
26 Stirrup bar (general gate type), 31 Upper bar (steel bar in the direction of water gradient),
32 Upper bar (steel bar in the direction approximately orthogonal to the water gradient), 33 Lower bar (steel bar in the direction of the water gradient),
34 Lower bar (steel bar approximately orthogonal to the water gradient), 35 Stirrup bar (cover),
36 Tarlap muscle (abstract), 37 gate-shaped central side, 38 gate-shaped both sides,
39 Higher side surface of water gradient of steel bars on both sides of gantry, 40 hooks, 41 end streaks,
51 I-shaped formation (vertical arrangement), 52 I-shaped formation (horizontal arrangement), 53 inverted L-shaped formation,
54 Each surface of the formation, 55 Each end of the formation, 57 Separation of the plan view,
58 Casting range including the upper surface side of the upper bar, 59 Casting range facing the lower surface side of the upper bar,
60 control panel, 61 side formwork, 62 horizontal end thick material, 63 vertical end thick material,
64 Separator steel bar (for penetration), 65 Box hardware,
66 P-con (plastic cone), 67 existing concrete,
68 Anchor steel bar (for fixing stirrup bar 26),
69 Separator steel bar (for fixing upper bar 31), 70 foundation concrete,
71 concrete press-fitting device, 72 guide pipe, 73 lower end of guide pipe, 74 fixed girder,
75 Connection material, 76 Reticular formation pump hose insertion hole, 77 Coarse aggregate arching effect,
79 caulking material, 80 caulking pins, 81 pump hoses (filling),
82 Vibrator (compacting), 83 Wooden trowel (rough finish), 84 Dragonfly (rough finish),
85 manpower tamper (tamping), 86 engine tamper (tamping),
87 Vibrating body, 88 Gold trowel (final finish), 89 Trowell (final finish),
90 rotating body, 91 driving order, 92 driving range I, 93 driving range II,
94 driving range III, 95 driving range IV, 95 driving range V, 96 horizontal driving range,
97 Gradient casting range, 98 Stirrup bar (bar type),
99 Hook part (tip plate type)

Claims (4)

An assembly structure for placing roadbed concrete,
The orientation of the surface formed by the linear first vertical and horizontal steel bars assembled in a general lattice pattern roughly matches the orientation of the upper surface of the roadbed concrete, and the direction of any of the first vertical and horizontal steel bars is the direction of the upper surface. An upper bar made of the first vertical and horizontal steel bars, which is approximately orthogonal to the direction of the water gradient and is arranged with a predetermined covering portion from the upper surface.
It has a structure in which the direction of any of the linear second vertical and horizontal steel bars assembled in a general lattice pattern roughly matches the direction of the steel bars that are approximately orthogonal to the direction of the water gradient of the first vertical and horizontal steel bars. , The lower bar made of the second vertical and horizontal steel bars arranged with a predetermined covering portion from the lower surface of the roadbed concrete, and
As an embodiment for restraining the separation between the upper bar and the lower bar, one of the first vertical and horizontal steel bars forming the upper bar and the second vertical and horizontal bar steel forming the lower bar is used. A roadbed reinforcing bar having hook portions at both ends thereof and having a stirrup bar arranged so as to be hooked at the hook portion of a third steel bar that forms a general gate type or a rod shape.
It comprises a plurality of reticular formations having at least one or more planes striped and elongated.
In the narrow space between the first vertical and horizontal steel bars forming the upper bar and the second vertical and horizontal steel bars forming the lower bar, the axial direction of the plurality of net bodies is approximately orthogonal to the direction of the water gradient, and at least. One of the planes of the net body faces the steel bar portion of any of the approximately vertical bars of the third steel bar forming the stirrup bar, or faces the lower surface of the first vertical and horizontal steel bars. Arranged, at least one end of the plane of the net body in cross-sectional view faces the lower surface of the first vertical and horizontal steel bars and is arranged in the slope portion in vertical cross-sectional view in the direction of the water gradient. An assembled structure composed of a network structure. The assembled structure according to claim 1.
Further having a side formwork to be placed on the higher side in the direction of the water gradient
Fixed along the steel bars that roughly match the direction of the water gradient of the first vertical and horizontal steel bars forming the upper bar, or the steel bars that roughly match the direction of the water gradient of the first vertical and horizontal steel bars. An assembly structure characterized in that a steel bar for a separator is fixed to the back surface of the side formwork. A concrete press-fitting device that is attached to and detached from the assembly structure according to claim 1 or 2.
A downward guide pipe that inserts a concrete pump hose and protrudes downward from the upper bar,
A fixed girder consisting of at least two rows in which the guide tube is arranged in the generally rectangular opening of the first vertical and horizontal steel bars forming the upper bar.
A concrete press-fitting device composed of a connecting material that sandwiches the guide pipe between the two rows of the fixed girder and connects the two rows. The method for placing roadbed concrete on the assembled structure according to claim 1 or 2.
With respect to the casting range facing the lower surface side of the upper bar, the net body arranged adjacent to the approximately vertical surface of the net body arranged on the lower side of the water gradient and the higher side of the water gradient. In a narrow space with the approximate vertical surface of the reticular formation, a method of placing roadbed concrete to at least one end facing the lower surface of the upper bar on the approximately vertical surface of the reticular formation arranged on the lower side is sequentially graded. The first step of raising and repeating the narrow space a predetermined number of times,
Subsequently, with respect to the casting range including the upper surface side of the upper bar, the second step of placing the roadbed concrete by sequentially lowering the gradient from the one having the higher water gradient to the finished surface of the upper surface of the roadbed. How to place roadbed concrete with.

Images