JP4641257B2 - Construction method of concrete - Google Patents

Description

  The present invention relates to a shaded concrete constructed at the top end of an underground wall and a construction method thereof.

  In recent years, as a technique for constructing semi-underground roads such as digging split roads and open-cut tunnel roads, for example, H-type PC (pre-stressed concrete) piles, etc. After constructing two underground walls that are continuously submerged in the ground with adjacent square PC piles, steel pipe sheet piles, etc., and after applying waterproofing treatment, beam processing, etc., two underground walls There is a technology to dig up the semi-underground road in between and form a bottom plate to create a semi-underground road.

  In addition, when constructing an upper floor slab on such a semi-underground road, cap concrete is installed at the top of each of the two underground walls, and a girder is placed on the cap concrete. There is a technique in which the same wall is used as a road girder after construction is completed (see, for example, Patent Document 1).

In this case, since the cap concrete acts as a girder support member and a beam support member, it was necessary to firmly bond with the underground wall. Conventionally, this kind of concrete is assembled after the formation of the underground wall, a formwork for forming the concrete on the top of the underground wall is assembled, and then the cast-in-place concrete is casted after rebar is assembled in the formwork. After the strength has developed over a period of time, it is used as the above-mentioned beam support member.
JP 2005-23576 A

  However, it is generally necessary to assemble the formwork at the site and place the cast-in-place concrete using conventional means, which generally requires a lot of man-hours for the material transporting means, etc., and requires a long curing period. It also takes a lot of time to erection, removal, etc. For this reason, the construction period of the shade concrete will occupy about 1/3 of the construction period of the semi-underground road, for example, leading to a longer construction period and a longer traffic regulation period. It was a great inconvenience to the residents.

  In view of the above circumstances, an object of the present invention is to provide a shade concrete suitable for rapid construction and a construction method thereof.

The cap concrete of the present invention that achieves the above object is
The lower surface is provided with a concave groove and both leg portions straddling the top end of the underground wall, the girder placing portion and the girder axial force support wall are provided on the upper surface,
In the above-mentioned concave groove, a reinforcing bar that is connected to the underground wall is projected, and a through-hole for introducing concrete into the concave groove is provided,
It is a precast concrete block having a long dimension along the underground wall.

  Further, the cap concrete of the present invention may have a hollow shell structure as a whole.

  The length of the cap concrete according to the present invention in the direction along the underground wall was a long precast concrete block suitable for the transportation means from the precast block manufacturing yard to the construction position. Therefore, the conventional formwork that forms the cap concrete is assembled on-site, rebars are assembled in this formwork, cast-in-place concrete is cast to form the cap concrete, The process of removing the assembled formwork is not necessary, and the precast concrete block is transported and mounted on the underground wall, so that the work period for constructing the cap concrete is shortened. Further, the cap concrete of the present invention comprises the reinforcing bar and the through hole for mechanically integrating the joint portion of the underground wall and the cap concrete of the present invention when constructing the cap concrete. In addition, since the girder placing portion and the girder axial direction force support wall are provided on the upper surface, the concrete can be used as the girder support member and the beam support member.

  In addition, the method for constructing the cap concrete of the present invention that achieves the above-mentioned object is provided with a space for reinforcing concrete to be provided in advance on the top of the underground wall. Concrete is straddled on the top end of the underground wall, and the reinforcing bars protruding in the concave groove of the cap concrete are mechanically connected to the reinforcing bars protruding in the void, and the cap concrete is provided. It is characterized in that the interstitial concrete is cast into the void from the through hole so that the underground wall and the shaded concrete are joined together.

  Since the method for constructing the concrete of the present invention uses the concrete of the present invention comprising precast concrete blocks, the construction period is compared with the conventional means for assembling the formwork and placing the cast-in-place concrete on site. Is greatly shortened. Moreover, the method for constructing the cap concrete according to the present invention is provided in advance on the reinforcing bars projecting in the concave grooves of the cap concrete according to the present invention straddling the top end of the underground wall and the top of the underground wall. By mechanically connecting the reinforcing bars projecting in the void, and placing through-hole concrete in the void from the through hole provided in the cap concrete, the above-mentioned underground wall and the cap concrete are integrated together. Since it is what is joined, the joint part of the underground wall and the shade concrete is made into an integral structure dynamically, and the constructed shade concrete can be used as a girder support member and a beam support member.

  Here, the method for constructing the cap concrete of the present invention includes mounting an elastic member on the top end of the underground wall, and straddling the cap concrete of the present invention on the top end of the underground wall through the elastic member. Therefore, the elastic member can absorb the construction error of the underground wall, which is preferable.

  In addition, the method for constructing the cap concrete of the present invention having a hollow shell structure is a method of attaching a precast concrete thin plate to form a cap concrete shell structure to the top of the underground wall, The concrete padding is placed at the same time, and the cap concrete and the underground wall are integrated at the same time as the cap concrete is formed.

  In this shade concrete construction method, since the precast concrete thin plate manufactured in advance is used as a formwork of the shade concrete to be constructed, the step of removing the formwork is not required, and the construction period is shortened. In addition, the method for constructing the cap concrete is that the precast concrete formwork concrete using the precast concrete thin plate and the above-mentioned interstitial concrete are simultaneously placed and integrated with the precast concrete formwork, The joint portions of the underground wall, the shaded concrete and the precast concrete formwork are mechanically integrated, and the constructed shaded concrete can be used as a girder support member and a beam support member.

  According to the cap concrete of the present invention, the cap concrete is a precast concrete block. Therefore, compared with the conventional means of assembling the formwork and placing cast-in-place concrete on site, the work period for installing the cap concrete is shorter. Shortened. Further, according to the cap concrete of the present invention, when the cap concrete is constructed, the reinforcing bar and the through hole for mechanically integrating the connecting portion of the underground wall and the cap concrete of the present invention are provided. Since it is equipped with the girder mounting part and the girder axial direction force support wall on the upper surface, the cap concrete can be used as a girder support member and a beam support member.

  In addition, according to the method of constructing the cap concrete of the present invention, by using the cap concrete made of the precast concrete block of the present invention, compared with the conventional means for assembling the formwork and placing cast-in-place concrete on site. The construction period is greatly shortened. Further, according to the method for constructing the concrete of the present invention, the reinforcing steel on the side of the concrete made of the precast concrete block is connected to the reinforcing steel on the side of the underground wall, and the underground wall is formed from the through hole provided in the concrete. By placing the interstitial concrete in a space provided in advance at the top of the wall, the joint portion between the underground wall and the shaded concrete is mechanically integrated, and the constructed shaded concrete is used as the girder support member and It can be used as a beam support member.

  In addition, according to the method for constructing the cap concrete of the present invention having a hollow shell structure, a step of removing the formwork is unnecessary by using a pre-cast concrete sheet made in advance as the formwork of the cap concrete to be constructed. The construction period is shortened. In addition, according to the method of constructing this shade concrete, by simultaneously placing the precast concrete formwork concrete using the precast concrete thin plate and the above-mentioned interstitial concrete and integrating with the precast concrete formwork, The joint portions of the underground wall, the shaded concrete, and the precast concrete form are mechanically integrated, and the constructed shaded concrete can be used as the girder support member and the beam support member.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a front view showing a cross section of a precast cap concrete 10 to which an embodiment of the cap concrete of the present invention is applied.

  The precast shade concrete 10 shown in FIG. 1 has a long dimension in which the dimension in the direction along the underground wall (not shown) has a portable length suitable for, for example, a transportation means from the precast block manufacturing yard to the construction position. The precast concrete block includes a concave groove 10a and both leg portions 10b straddling the top end of the underground wall on the lower surface, and a girder placing portion 10c and a girder axial force support wall 10d on the upper surface. In addition, the width of the concave groove 10a provided on the lower surface of the precast shade concrete 10 is slightly larger than the thickness of the underground wall in order to absorb the construction error of the underground wall. In addition, a reinforcing bar 30 that is connected to the underground wall projects from a recessed groove 10 a provided on the lower surface of the precast shade concrete 10. Further, the precast shade concrete 10 is provided with a through hole 10e through which the concrete is poured into the concave groove 10a.

  Thus, according to the precast cap concrete 10 of this embodiment, since this precast cap concrete 10 is a precast concrete block, the formwork which forms the cap concrete which was performed by the conventional means is assembled on-site. Or assemble reinforcing bars in this formwork, cast cast-in concrete to form shade concrete, or remove the assembled formwork, and transport the precast concrete block to the ground Since it is mounted on the wall, the work period for constructing the concrete is shortened. In addition, the precast shaded concrete 10 of the present embodiment has a reinforcing bar 30 and a through hole for mechanically integrating the joint portion between the underground wall and the precast shaded concrete 10 when the precast shaded concrete 10 is constructed. 10e and the girder mounting portion 10c and the girder axial force support wall 10d are provided on the upper surface, so that the precast shade concrete 10 can be used as a girder support member and a beam support member.

  Next, the construction method to which one embodiment of the construction method of the shade concrete of the present invention is applied will be described. Here, the ground is formed by continuously sunk H-shaped PC piles adjacent to the side walls on both sides of the ground on which one side two-lane semi-underground road with a 25 m girder extension is to be built. The example which constructs a middle wall and constructs the precast shade concrete 10 shown in FIG. 1 on the constructed underground wall is demonstrated with reference to FIGS.

  2 is a side view showing a state in which the precast concrete cap 10 shown in FIG. 1 is straddled on the top end 20c of the underground wall 20, and FIG. 3 is a front view showing a transverse section in the state shown in FIG. .

  First, the adjacent H-shaped PC piles 21 are opposed to each other in the axial direction and meshed with the notches formed at the edges of the grooves to form side walls on both sides of the ground on which the semi-underground road is to be created. The H-shaped PC pile 21 is adjacent to the part and is continuously sunk in the ground to construct a double underground wall 20.

  Next, the reinforcing bar 31 is inserted into the internal space 20a formed by the adjacent recesses of the H-shaped PC pile 21 of the built underground wall 20, and the cast-in-place concrete 40 is placed in the internal space 20a for curing. To do. In placing the cast-in-place concrete 40, a void 20b is formed in which a reinforcing bar 31 is projected from the top of the internal space 20a of the underground wall 20 and in which the concrete is placed in a later step. To be placed. Further, the reinforcing bar 31 projecting in the void 20b is placed in the concave groove 10a of the precast cap concrete 10 when the precast cap concrete 10 shown in FIG. 1 is straddled on the top end 20c of the underground wall 20. The bars are arranged so as to be mechanically connected to the protruding reinforcing bars 30.

  Next, an elastic member 50 having a height of about 50 mm is placed on the top end 20c of the underground wall 20 in which the cast-in-place concrete 40 is placed in the internal space 20a, and the precast shade concrete 10 shown in FIG. Then, it is straddled over the top end 20 c of the underground wall 20 through the elastic member 50. Thus, it is preferable because the elastic member 50 can absorb the construction error of the underground wall 20 by straddling the precast concrete cap 10 on the underground wall 20 via the elastic member 50.

  The precast shaded concrete 10 straddled on the underground wall 20 is fixed to the underground wall 20 by adjusting the position and height using the precast shaded concrete installation bracket 60.

  Next, when casting the cast-in-place concrete 40 in the internal space 20a of the underground wall 20, the precast shade concrete straddled on the underground wall 20 in the space 20b formed at the top of the internal space 20a. 10 is placed and cured from through-holes 10e provided in 10. Further, the precast shade concrete installation bracket 60 used in the previous process is removed after the intercalation concrete 41 placement curing.

  FIG. 4 is a front view showing a transverse section in a state in which the interstitial concrete 41 is placed in the space 20 b of the underground wall 20.

  The reinforcing bar 31 protruding in the space 20b of the underground wall 20 is mechanically connected to the reinforcing bar 30 protruding in the recessed groove 10a of the precast cap concrete 10 straddled on the underground wall 20. In the previous step, by placing the intercalated concrete 41 in the space 20b of the underground wall 20 from the through hole 10e of the precast shade concrete 10 and curing it, The middle wall 20 and the precast shade concrete 10 are joined together.

  Here, the width of the concave groove 10 a provided on the lower surface of the precast shade concrete 10 is slightly larger than the thickness of the underground wall 20 in order to absorb construction errors of the underground wall 20. Therefore, when the precast shade concrete 10 is straddled on the underground wall 20, a gap is generated between the side surface of the H-shaped PC pile 21 that forms the underground wall 20 and both legs 10 b of the precast shade concrete 10. Become. Therefore, if necessary, the gap is filled with a putty-like caulking material 80 to close the gap.

  Since the method for constructing the shade concrete described with reference to FIGS. 2 to 4 uses the precast shade concrete 10 made of the precast concrete block, the conventional method of assembling the formwork and placing the cast-in-place concrete on site. Compared with the means, the construction period of the cap concrete is greatly shortened. For example, in the example of the semi-underground road construction shown in FIGS. 2 to 4, the construction period of the cap concrete is about 1/4.

  In addition, the method for constructing the cap concrete is provided in advance on the reinforcing bar 30 projecting in the concave groove 10 a of the precast cap concrete 10 straddling the top end 20 c of the underground wall 20 and the top of the underground wall 20. The reinforced concrete 31 projecting in the empty space 20b is mechanically connected, and the interstitial concrete is cast into the empty space 20b from the through hole 10e provided in the precast cap concrete 10 Since the wall 20 and the precast shade concrete 10 are integrally joined, the joint portion between the underground wall 20 and the precast shade concrete 10 is mechanically integrated, and the constructed shade concrete is used as a girder support member. And can be used as a beam support member.

  FIG. 5 is a front view showing a cross section in a state where the semi-underground road 1 is constructed by constructing the precast upper floor slab 91 and the bottom plate 92.

  After the precast shade concrete 10 is constructed on the underground wall 20 in the previous step, the precast upper floor slab 91 is placed on the precast shade concrete 10. This precast upper floor slab 91 is used as a beam to prevent the underground wall 20 from falling down during the construction work where the bottom slab 92 is formed by digging the semi-underground road ground between the two underground walls 20, and the same after the construction is completed. Use things as road girders.

  Thus, by using the precast concrete 10 made of precast concrete blocks, the construction period of the concrete is greatly shortened compared to the conventional means of assembling the formwork and placing cast-in-place concrete on site. As a result, the construction period for constructing the semi-underground road 1 is greatly shortened. For example, in the example of the semi-underground road construction shown in FIGS. 2 to 4, the total construction period is about 3/4.

  Next, the construction method to which an embodiment of the construction method of the cap concrete of the present invention having a hollow shell structure is applied will be described. In the example described below with reference to FIGS. 6 to 9, the difference from the example described with reference to FIGS. 2 to 5 is noted, and the same elements are denoted by the same reference numerals and description thereof is omitted. To do.

  FIG. 6 is a side view of a state in which the precast concrete thin plate 11 to form the shape of the shell structure of the shaded concrete is attached to the top of the underground wall 20, and FIG. 7 is a cross section of the state shown in FIG. FIG. 8 is an enlarged view of part A shown in FIG.

  At the top of the underground wall 20 constructed, a precast concrete thin plate 11 to be formed in the shape of a shell structure of shaded concrete is attached. In fixing the precast concrete thin plate 11 to the underground wall 20, a precast concrete thin plate fixing jig 12 and a precast concrete thin plate installation bracket 61 are used. Further, when attaching the precast concrete thin plate 11, in order to absorb the construction error of the underground wall 20, it is between the side surface of the H-type PC pile 21 forming the underground wall 20 and the precast concrete thin plate 11. A gap of about 30 mm is provided and attached, and this gap is closed with a gap filling rubber 13. Thus, the precast concrete thin plate 11 attached to the top of the underground wall 20 functions as a formwork of the cap concrete. Here, as shown in FIG. 7, the lower portion of the cap concrete, which is lower than the beam mounting surface 14 corresponding to the beam mounting portion 10 c of the precast cap concrete 10 shown in FIG. 1, is applied first.

  Next, rebars (not shown) are inserted in the precast concrete thin plate 11 attached to the top of the underground wall 20 and in the internal space 20a formed by the adjacent recesses of the H-shaped PC pile 21 of the underground wall 20. Then, the cast-in-place concrete 42 is simultaneously placed in the thin plate 11 made of precast concrete and the internal space 20a and cured, thereby forming a lower part than the girder mounting surface 14 of the cap concrete as shown in FIG. At the same time, the cap concrete and the underground wall 20 are integrated. Further, the precast concrete thin plate installation bracket 61 used in the previous step is removed after the cast-in-place concrete 42 is placed and cured.

  FIG. 9 is a front view showing a cross section in a state where the precast upper floor slab 91 is placed on the girder placing surface 14 and the cast-in-place concrete 43 is placed.

  As shown in FIG. 9, a precast upper floor slab 91 having a cushioning material 16 attached to the end is placed on the girder placement surface 14 formed in the previous step. When the precast upper floor slab 91 is mounted, the buffer material 16 forms a spar axial force support surface 15 corresponding to the spar axial force support wall 10d of the precast cap concrete 10 shown in FIG. Install to function as.

  Next, a reinforcing bar (not shown) is inserted into the space formed by the precast concrete thin plate 11 and the buffer material 16, and cast-in-place concrete 43 is placed in the space and cured.

  In the method for constructing the shaded concrete according to the embodiment described with reference to FIGS. 6 to 9, the precast concrete thin plate 11 manufactured in advance is used as a formwork for the shaded concrete to be constructed. This eliminates the need to perform the process and shortens the construction period.

  In addition, the method for constructing the cap concrete is that the precast concrete formwork concrete using the precast concrete thin plate 11 and the interstitial concrete are simultaneously placed and integrated with the precast concrete formwork. The joint portions of the middle wall 20, the shaded concrete, and the precast concrete form are mechanically integrated, and the constructed shaded concrete can be used as a girder support member and a beam support member.

  In each of the above-described embodiments, an example has been described in which the underground wall referred to in the present invention is an underground wall that is continuously submerged in the ground with H-type PC piles adjacent to each other. The underground wall is not limited to this, and any wall having a structure that can be firmly bonded to the shaded concrete may be used.

It is a front view which shows the cross section of the precast shade concrete with which one Embodiment of shade concrete of this invention was applied. It is a side view of the state which made the precast shade concrete shown in FIG. 1 straddle the top end of an underground wall. It is a front view which shows the cross section of the state shown in FIG. It is a front view which shows the cross section of the state which laid the concrete in the space of the underground wall. It is a front view which shows the cross section of the state which constructed the precast upper floor slab and the baseplate and created the semi-underground road. It is a side view of the state which attached the thin plate made from the precast concrete which should form the shape of the shell structure of the shade concrete to the top part of the underground wall. It is a front view which shows the cross section of the state shown in FIG. It is an enlarged view of the A section shown in FIG. It is a front view which shows the cross section of the state which mounted the precast upper floor slab on the girder mounting surface, and cast the cast-in-place concrete.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Precast shade concrete 10a Concave groove 10b Both legs 10c Girder mounting part 10d Girder axial direction force support wall 10e Through hole 11 Precast concrete thin plate 12 Precast concrete thin plate fixing jig 13 Rubber for gap filling 14 Girder mounting surface 15 Girder axial force support surface 16 Buffer material 20 Underground wall 20a Internal space 20b Empty space 20c Top end 21 H-type PC pile 30, 31 Reinforcement 40, 42, 43 Cast-in-place concrete 41 Filled concrete 50 Elastic member 60 Installation of precast concrete Bracket 61 Precast concrete plate installation bracket 80 Caulking material 91 Precast upper floor plate 92 Bottom plate

Claims (2)

In the top of the underground wall formed by connecting concrete piles, a space is provided in advance to place the concrete to be stuffed with reinforcing bars, and an elastic member is placed on the top end of the underground wall. a concave groove sits astride the top end of the underground wall, and Ketano portion, and column axial force the support wall, a reinforcing bar is protruded to bind the diaphragm wall before Symbol the groove, the concrete said shade concrete consisting of precast concrete blocks with a through hole to be introduced into the concave groove via said elastic member was straddled translocated to the top end of the underground wall, the through hole provided in該笠concrete A method for constructing a concrete covering, characterized in that interstitial concrete is placed in a void and the underground wall and the concrete covering are integrally coupled . In the top of the underground wall made by connecting concrete piles, there is a space for reinforcing concrete to be placed, and a hollow concrete shell structure is formed. A precast concrete thin plate to be attached is attached to the top of the underground wall, and the precast concrete thin plate concrete and the interstitial concrete are simultaneously placed, and simultaneously with the formation of the shade concrete, the shade concrete and the underground wall construction method of shade concrete you, characterized in that the integration of the.

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