JPH0820936A - Erection of concrete wall - Google Patents

Abstract

PURPOSE:To stably install precast concrete panel forms although tie-bars which obstructs placing of concrete are eliminated on installing the precast concrete panel forms and at the same time enable independent directional correction and further, increase the construction speed and secure the safety of the works. CONSTITUTION:Connection members 14 fixed at the rear face of the lower stage precast concrete panel forms (called as form hereunder) 11a, 12a and projected from the upper end of the forms are fixed at the rear face of stacked forms 11b, 12b to connect the upper and lower forms together. When the connection members 14 are fixed at the rear face of the stacked forms, spacers with appropriate thickness are inserted between the rear face of the lower stage form and the connection member or the rear face of the stacked form and the connection member to correct the inclination of the stacked form.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing a concrete wall, and more particularly to a method for constructing a concrete wall in a sabo dam using a precast concrete panel formwork.

[0002]

2. Description of the Related Art Conventionally, there has been known a construction method in which a precast concrete panel is used as a formwork in the construction of a concrete wall of a sabo dam, a concrete gravity type wall, etc., and finally it is buried together with concrete pouring.

In a concrete placing method using such a conventional precast concrete panel formwork (hereinafter, simply referred to as a preconpanel formwork), a method of assembling a preconpanel formwork will be described by taking a case of constructing a sabo dam as an example. explain. 8 and 9 are front views of the wall surface 1 on the upstream side and the wall surface 2 on the downstream side in the sabo dam formed by the pre-control panel formwork, respectively.

When constructing such an erosion control dam by a pre-control panel formwork, first, the pre-control panel formwork 3 is laterally arranged at a predetermined distance between a position on the downstream side and a position on the upstream side. Will be installed in series. In the case of constructing a concrete wall in a sabo dam, as shown in FIG. 10, the pre-control panel formwork 3 on the upstream side is arranged vertically, while the pre-control panel formwork 3 on the downstream side is installed slanted.

On both the upstream surface side and the downstream surface side, on the inner surface of the pre-control panel formwork, an L-shaped steel (angle material) 4 serving as a vertical rib material as shown in a partially enlarged view in FIG. It is firmly fixed with a bolt 5 or the like so that about half of it protrudes from the part. This angle member 4 is mainly used for connecting other pre-control panel formwork 3 which is then stacked on the pre-control panel formwork 3.

Preconpanel formwork 3 installed on the upstream side
The pre-control panel formwork 3 installed on the downstream side is connected to each other by a tie bar 6 with a turnbuckle to stabilize the installation. When the tie bar 6 is attached to each pre-control panel form 3, the ends of the tie bar 6 are welded to the angle members 4 of the pre-control panel form 3 facing each other. Then, the turnbuckle 7 of each tie bar 6 is rotated to adjust the interval thereof, and thereby the fine adjustment is made so that the gradient, that is, the inclination angle of the pre-control panel formwork 3 on the downstream side becomes as designed.

Between the upstream side and downstream side pre-control panel formwork 3 assembled in this way, concrete 8 is filled to a level below the upper edge thereof. After that, when the filled concrete 8 is cured and hardened, a new pre-control panel form 3 is stacked on the upper edges of the upstream and downstream side pre-control panel forms 3 projecting from the existing concrete by the same procedure and the existing It is fixed to the angle member 4 protruding from the pre-control panel form 3. Of course, an angle member 4 for connecting the next pre-control panel formwork is also attached to the inside of the newly stacked pre-control panel formwork 3 so as to project from the upper edge portion.

Then, tie bars 6 are attached to the newly stacked upstream side and downstream side pre-control panel formwork 3 to stabilize the installation of the pre-control panel formwork 3 on both sides, and their intervals are adjusted. Concrete is poured. While repeating such a process, concrete was poured to a predetermined height to construct a sabo dam having a desired shape.

[0009]

However, in the construction of the concrete wall using such a conventional pre-control panel formwork, there are the following problems. That is, in the conventional method for constructing a concrete wall of this type, firstly, there is a problem that the tie bar becomes an obstacle when the concrete is poured.

Secondly, since the pre-control panel mold 3 is deformed by the concrete pressure applied, it is necessary to make some direction correction when the pre-control panel mold 3 is sequentially assembled upward. When attempting to correct the direction of the pre-control panel formwork with a tie-bar tan buckle, there is a problem that it is difficult to independently correct the pre-control panel formwork on both sides because the same tensile force is applied to the pre-control panel formwork.

Thirdly, the slack due to the weight of the tie bar causes a pulling error during the assembly of the precon panel formwork, and after the concrete is placed, an error due to the return of the slack causes the preconform formwork as designed. There was a problem that it was very difficult to secure.

Fourth, in the case of a concrete wall in a sabo dam, for example, it is impossible to install a crane used for assembling the pre-control panel formwork between the pre-control panel formwork due to the tie bar obstruction. Therefore, it must be placed outside the formwork for operation. As a result, there is a problem in that the work for assembling the pre-control panel formwork by the crane is restricted, and as a result, it can be used only for a small-scale dam.

Finally, from the above-mentioned second and third problems, the pre-control panel formwork 3 is piled up in several stages in advance to increase the construction speed, and it is used as a safety protection wall for workers on the existing concrete surface. Therefore, especially for the latter, it is necessary to temporarily install a safety handrail and remove it repeatedly, and it is necessary to perform repeated work such as removing the construction cost and shortening the construction period. It was

The object of the present invention is to solve the above-mentioned conventional problems. The precast concrete panel is eliminated while eliminating the tie bar which obstructs the concrete placement when installing the precast concrete panel formwork. It is an object of the present invention to provide a method for constructing a concrete wall, which enables stable installation of a formwork, enables independent direction correction, and improves construction speed and ensures work safety.

[0015]

The present invention is a concrete wall construction method, which is configured as follows in order to solve the above-mentioned technical problems.

<First Invention> According to the present invention, concrete is placed between precast concrete panel forms which are installed at intervals, and the precast concrete panel forms are piled up as the cast concrete hardens, and thereafter. In the method of constructing a concrete wall by repeating the step of placing concrete again, a precast concrete panel mold for stacking a connecting material that is fixed to the back surface of the precast concrete panel mold for the lower tier and projects from the upper end Including a step of connecting the upper and lower precast concrete panel formwork to each other by fixing to the backside of the frame, and fixing the connecting material to the backside of the stacked precast concrete panel formwork, the precast concrete panel formwork of the lower stage Between the back surface and the connecting material or the product The inclination of the precast concrete panel formwork of the stacking stage is corrected by inserting a spacer having an appropriate thickness between the back surface of the precast concrete panel formwork of the stacking stage and the connecting material (claim 1). Correspondence). The constituent elements of the present invention will be individually described below.

(Upper and lower precast concrete panel formwork interconnection process) When the precast concrete panel formwork is piled up as the cast concrete hardens, it is fixed to the back surface of the precast concrete panel formwork in the lower stage and from the upper end thereof. The protruding connecting material is fixed to the back side of the precast concrete panel formwork in the stacking stage.
As the connecting material, a section steel called a so-called angle material is used. A hole for inserting a bolt is formed at a predetermined position in this angle member, and an insert bolt is passed through this hole to fix the angle member to the precast concrete panel formwork.

In the concrete wall construction method of the present invention, the lower precast concrete panel formwork on which the precast concrete panel forms are stacked is
Being anchored by the existing concrete, the angle members primarily serve to support the precast concrete panel formwork to be stacked.

Therefore, the angle member is applied to the back surface of the precast concrete panel formwork in the upper step, which is the part where the length of the part applied to the back surface of the precast concrete panel formwork in the lower step projects from the upper end. It is shorter than the length of the part, and the number of insert bolts that fix the angle member to the back of each precast concrete panel formwork is one bolt that is fixed to the lower step, and the number of bolts that are fixed to the upper step is It can be two.

(Spacer charging step) When another new precast concrete panel formwork is stacked on the lower stage precast concrete panel formwork, it is necessary to correct its direction, that is, the inclination angle. In that case, when fixing the stacked precast concrete panel formwork to the angle material that extends from the lower stage precast concrete panel formwork using insert bolts, etc., And a spacer of appropriate thickness between the back surface of the precast concrete panel formwork in the stacking stage and the angle member.

As such a spacer, a C-shaped metal washer adapted to be bitten by the insert bolt can be used. Also, adjustment of the spacer thickness is
This is possible by selecting the number of washers.

<Second Invention> In the present invention, concrete is placed between precast concrete panel forms installed at intervals, the precast concrete panel forms are stacked as the set concrete hardens, and thereafter, In the method of constructing a concrete wall by repeating the step of placing concrete again, in the precast concrete panel formwork of the stacking step, the other end of the stay attached to the back side of the precast concrete is embedded in the previously cast concrete. It is characterized by supporting a panel form (corresponding to claim 2). The components of the present invention will be described below.

(Stay Attaching Step) The stay is used to reduce bending stress on the angle member due to concrete pressure. The stay is formed of a metal rod, and one end of the stay is attached to the back surface of the upper precast concrete panel formwork. For this attachment, the precast concrete panel formwork can be connected to the angle member by welding or the like. However, the mounting method is not limited to this. For example, one end of the stay may be bent into a hook shape and hooked in a hole formed in the angle member to be attached.

The other end of this stay is embedded in the cast concrete to form an anchor portion. Therefore, the shape or configuration of the other end of the stay does not matter. However, it is preferable to bend and form an L-shape or a U-shape in order to provide resistance against pulling out so as not to easily separate from the poured concrete.

<Third Invention> The present invention is a method for constructing a concrete wall using a large number of precast concrete panels as a formwork. First, a first connecting member is fixed to the back surface so as to project from the upper end. The step of appropriately installing the precast concrete formwork of the second stage on the ground with a space, and similarly, another precast concrete panel formwork of the second stage is attached to the back surface so that the connecting material projects from the upper end. The connecting material that is stacked on the first-stage precast concrete panel formwork and extends upward from the stacked second-stage precast concrete panel formwork from the first-stage precast concrete panel formwork The step of fixing the concrete, then the step of placing concrete within the interval, and Before hardening, the other end of the stay, one end of which is attached to the connecting material that connects the first-stage and second-stage precast concrete panel formwork, is embedded in the pouring concrete and the pouring is performed. The step of fixing by hardening the concrete, and the step of attaching the connecting material to the back surface of the second-stage precast concrete formwork so as to project from the upper end again on the second-stage precast concrete formwork after the casting concrete has hardened. Stacking another precast concrete panel formwork on the third stage and fixing it to the connecting material extending upward from the precast concrete formwork on the second stage, and then the precast concrete panel form on the third stage A step of placing concrete within a space defined by a frame, and the large first-stage precast concrete panel Repeat other the step of removing the frame installation process, characterized in that concrete is cast to a predetermined height (corresponding to claim 3).

In the second invention, the constituent elements of the second invention are added to the constituent elements of the first invention described above. Therefore, since the individual constituent elements have been described in the above-described inventions, the description thereof is omitted here.

[0027]

The concrete wall construction method of the present invention is roughly constructed by placing concrete between precast concrete panel forms that are installed at intervals, and the precast concrete panel forms are formed as the cast concrete hardens. The concrete wall is constructed by repeating the steps of stacking and then placing concrete again.

In such a concrete wall construction method, another precast concrete panel formwork is newly stacked on the precast concrete panel formwork for existing concrete. At that time, the precast concrete panel formwork of the stacked stage is fixed to the back surface of the precast concrete panel formwork of the stage below it, and is fixed to the connecting material protruding from the upper end portion thereof to achieve mutual connection.

When fixing the connecting material to the back surface of the precast concrete panel formwork of the stacking stage, if it is necessary to correct the inclination of the precast concrete panel formwork of the stacking stage, connect it to the backside of the precast concrete panel formwork of the lower stage. A spacer with an appropriate thickness is inserted between the timber or between the backside of the stack of precast concrete panel formwork and the connecting material, so that the inclination of the stack of precast concrete panel formwork is as designed. Adjusted.

When concrete is placed between the precast concrete panel forms installed in this way, bending stress due to concrete pressure acts on the angle members connecting the vertically stacked precast concrete panels. . The stay attached to the angle member acts to reduce the bending stress.

[0031]

EXAMPLES The concrete wall construction method of the present invention will be described below in more detail with reference to the examples shown in the drawings.
FIG. 1 shows a precast concrete panel formwork (pre-conpanel formwork) assembly structure 10 for constructing a concrete wall for a sabo dam using the concrete wall construction method of the present invention. In the method for constructing a concrete wall of a sabo dam according to this embodiment, first, the first-stage pre-control panel formwork 1 is provided at the upstream side and the downstream side, respectively.
1a and 12a are installed on the ground at intervals with the L steel material 13 and the like as supports.

At this time, it goes without saying that the upstream side and downstream side pre-control panel molds 11a and 12a are also closely attached to each other in the lateral direction, and a large number of them are installed over a predetermined length. Since there is a vertical connection relationship when stacking the pre-control panel formwork, a description of the installation of the pre-control panel formwork in the horizontal direction is omitted.

The pre-control panel formwork 11a located upstream of the erosion control dam is erected vertically, while the pre-control panel formwork 12a located downstream is installed at an angle. First
As shown in FIGS. 1 and 2, the pre-contain panel formwork 11a, 12a of the tier is fixed with insert bolts 15 or the like so that an L-shaped angle member 14 which is a shape steel for connection is projected from the upper end on the rear surface. It has been installed.

This angle member 14 is used to connect the pre-conpanel forms that are stacked on each other, and particularly supports a new pre-conpanel form that is stacked on the lower pre-conpanel forms. The main purpose is that. Therefore, as is apparent from FIG. 2, the angle member 14 is fixed to the back surface of the lower pre-conpanel formwork by a single insert bolt 15 at a length of about 1/3 of the entire length from the lower end thereof. The two-thirds of the length projects from the upper end of the lower preconpanel formwork to support the stacked preconpanel formwork.

Then, the angle member 14 is formed on the back surface in this manner.
First stage pre-con panel formwork 11 with attached
On the upper ends of a and 12a, new pre-control panel molds 11b and 12b are stacked as the second stage. As a result, the first-stage pre-control panel formwork 11a, 12a
The angle member 14 projecting from the upper end of is overlapped with the back surface of the second-stage pre-control panel formwork 11b, 12b, which is a stacking stage, and is fixed by two insert bolts 15, respectively.

Incidentally, the angle members 14 for supporting the pre-control panel formwork of the next stacking stage are also preliminarily attached to the back surface of the second-stage pre-control panel formwork 11b, 12b in the same manner as described above. Needless to say

By the way, in stacking the pre-control panel molds, in order to facilitate accurate superposition of the upper end surface of the lower pre-control panel molds and the lower end surface of the upper pre-control panel molds, FIG. As shown, a protrusion 16 is formed over the entire width in the center of the upper end surface, while a groove 1 is formed in the center of the lower end surface so that the protrusion 16 fits snugly.
7 are formed. As a result, when the pre-control panel molds are stacked, they can be accurately positioned by simply placing them on the upper surface of the lower pre-control panel molds.

When stacking a new pre-control panel form on the upper surface of the lower-stage pre-control panel form, it may be necessary to correct the direction. How to correct this tilt angle
A case will be described in which, for example, a mold located on the downstream side is steeply inclined as shown by a dotted line in FIG.

First, the lower pre-control panel formwork 12
a) Loosen the insert bolt 15 that fixes the angle member 14 on the back surface, and insert one or more C-shaped washers 18 between the angle member 14 and the back surface of the pre-conpanel mold as shown in FIGS. 5 and 6. Hook it on the insert bolt 15 so that it can be inserted from the lateral direction. As a result, the angle of the angle member 14 with respect to the lower-stage pre-control panel formwork 12a is changed, and thus the inclination angle of the stacking-stage pre-control panel formwork 12b attached to the angle member 14 is corrected.

On the contrary, as shown by the dotted line in FIG. 7, when the inclination angle of the stacking-stage pre-control panel formwork 12b is corrected to the gentle slope side, the stacking-stage pre-control panel formwork 12b is provided on the rear surface. When fixing the angle member 14 with the insert bolt 15, one or more C-shaped washers 18 are inserted in the same manner as shown in FIG. However, depending on the size of the change angle of the angle member 14, it is necessary to loosen the insert bolt 15 that is fixed to the pre-control panel formwork in the lower stage.

In the above-mentioned example, the method for correcting the inclination of the pre-control panel formwork installed on the downstream side has been described, but this is the same for the pre-control panel formwork installed not only on the downstream side but also on the upstream side. . That is, in this embodiment, the pre-control panel formwork installed on the upstream side is shown in FIG.
As you can see, they are stacked almost vertically.

If the molds are simply stacked vertically, it is not necessary to correct the direction, but the lower mold may be displaced by concrete pressure. In such a case, correction is necessary. There is.

Also, the pre-control panel formwork located on the downstream side basically does not require much correction if the gradient is uniform. The need for modification in this case is also for deformation due to concrete pressure, as in the case of the upstream pre-control panel.

When the second-stage pre-control panel molds 11b and 12b are stacked in this way, concrete 19 is then placed between the upstream and downstream molds.
At this time, the concrete is poured as shown in FIG. 1 in the first-stage and second-stage pre-control panel formwork 11a, 11b.
And 12a, 12b are respectively driven up to near the lower end of the angle member 14.

A stay 20 having one end attached to the upper end side of the angle member 14 connecting the first-stage and second-stage pre-control panel formwork before the poured concrete 19 is completely hardened. The other end is embedded in the pouring concrete 19 and the stay 20 is fixed by hardening the pouring concrete 19. As a result, a stronger self-sustaining stabilization of the stacked pre-control panel formwork 11b, 12b can be obtained, and the bending stress to the angle member due to the pressure of the placing concrete can be reduced, so that the angle member 14 can be reduced in weight. You can also

When the cast concrete 19 is hardened, an operator rides on the concrete 19 and the new third-stage pre-control panel formwork 11c, 12c is added to the second-stage pre-control panel formwork 11b, 12b. Do the work of stacking. That is, after that, the above-mentioned steps are repeated, whereby the pouring of concrete is repeated until the predetermined height is reached.

As is clear from the above description, when the operator is performing the next pre-conpanel formwork stacking work and other necessary work on the surface of the cast concrete 19, the surface of the cast concrete 19 is removed. Since one or more pre-control panel formwork will always be erected, this will serve as a protective wall and prevent accidents such as falling of workers.

The stay 20 may be attached to the angle member 14 by welding, but as another method, one end of the stay 20 is bent into a hook shape and hooked in a hole (not shown) formed in the angle member 14. It can also be attached in this way. The other end of the stay 20 is embedded in the cast concrete to serve as an anchor, so that the shape and configuration of the other end are not particularly problematic. However, it is preferable to bend and form an L-shape or a U-shape in order to provide resistance against pulling out so as not to easily separate from the poured concrete.

As described above, in the concrete wall construction method for a sabo dam according to this embodiment, in order to stably install the precast concrete panel formwork, which is installed on the upstream side and the downstream side with a space as in the conventional case. As it does not require many tie bars to traverse between the forms, a relatively large space can be secured between the forms, so that a working crane can be placed between the forms, and as a result Large sabo dams can be constructed using this precast concrete panel formwork.

In the above-described embodiment, the case of constructing a concrete wall of a sabo dam has been described, but the present invention is not limited to this embodiment, and various concrete walls including concrete gravity type walls are precast concrete. It can be applied when forming with a panel form.

[0051]

As described above, according to the concrete wall construction method of the present invention, the precast concrete panel formwork arranged at intervals is used with the tie bar which traverses the formwork as in the prior art. Even if it is made to be self-supporting strongly without being, it is possible to easily correct the direction of the precast concrete panel formwork in the stacking stage.

Further, even if the tie bar is eliminated, the precast concrete panel formwork in the stacking stage can be made to stand on its own, so that there is no obstacle during concrete pouring, and extremely efficient concrete pouring can be performed. Moreover, since there is no tie bar, the space between the molds can be effectively used, and since two-tiered construction is possible, it is expected to be advantageous in terms of safety and improved construction efficiency. be able to.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a precast concrete panel formwork assembly structure in the case of constructing a concrete wall of a sabo dam using the concrete wall construction method of the present invention.

FIG. 2 is a partial front view showing a connection state of precast concrete panel formwork stacked in the precast concrete panel formwork assembly structure shown in FIG.

FIG. 3 is a cross-sectional view of the precast concrete panel formwork, which is stacked and connected in FIG. 2, taken along line 3-3.

FIG. 4 is a cross-sectional view similar to FIG. 3, showing a method of correcting the tilt angle of stacked precast concrete panel forms.

FIG. 5 is a cross-sectional view showing, in an enlarged manner, a fixing portion between an angle member and a precast concrete panel formwork at a lower stage in order to show a method of correcting an inclination angle of stacked precast concrete panel forms.

FIG. 6 is an enlarged front view showing a fixed portion between the lower precast concrete panel formwork and the angle member shown in FIG.

FIG. 7 is a sectional view similar to FIG. 3, showing a method of correcting the tilt angle of stacked precast concrete panel forms.

FIG. 8 is a front view showing an upstream concrete wall of a conventional sabo dam constructed using a precast concrete panel formwork.

FIG. 9 is a front view showing a downstream concrete wall of a conventional sabo dam constructed using a precast concrete panel formwork.

FIG. 10 is a cross-sectional view showing a conventional precast concrete panel formwork assembly structure in the case of constructing a concrete wall of a sabo dam.

FIG. 11 is an enlarged sectional view showing a part of the conventional precast concrete panel formwork assembly structure shown in FIG.

[Explanation of symbols]

10 Precast concrete panel formwork assembly structure 11a 1st stage precast concrete panel formwork 11b 2nd stage precast concrete panel formwork 11c 3rd stage precast concrete panel formwork 12a 1st stage precast concrete panel Formwork 12b Second-stage precast concrete panel formwork 12c Third-stage precast concrete panel formwork 13 Support steel material 14 Angle material 15 Insert bolt 16 Protrusion 17 Groove 18 C-shaped washer 19 Cast concrete 20 Stay

Claims (3)

[Claims] 1. A step of placing concrete between precast concrete panel forms installed at intervals, stacking the precast concrete panel forms with hardening of the placed concrete, and then placing concrete again. In the method of constructing a concrete wall by repeating it, the connecting material protruding from the upper end of the precast concrete panel formwork on the lower step is fixed to the backside of the stacked precast concrete panel formwork, The step of connecting the precast concrete panel formwork to each other, when fixing the connecting material to the back surface of the precast concrete panel formwork of the stacking step, between the back surface of the precast concrete panel formwork of the lower step and the connecting material. Or the precast of the stacking stage Concrete Wall construction method characterized by down cleat panel formwork rear surface and between said connecting members put appropriate thickness spacers to correct the inclination of the precast concrete panel formwork of the stacking stage. 2. A step of placing concrete between precast concrete panel formwork installed at intervals, stacking the precast concrete panel formwork as the cast concrete hardens, and then placing concrete again. In the method of constructing a concrete wall by repeating it, it is necessary to support the precast concrete panel formwork by embedding the other end of the stay with one end attached to the back surface of the precast concrete panel formwork of the stacking stage in the concrete cast last time. Characteristic concrete wall construction method. 3. A method for constructing a concrete wall by using a large number of precast concrete panels as a formwork, wherein first, a first-stage precast concrete formwork having a connecting material fixed to the back surface so as to project from the upper end is provided. The second precast concrete panel formwork of the second stage, which is appropriately installed on the ground at intervals and similarly attached to the back surface so that the connecting material projects from the upper end, is the precast concrete panel formwork of the first stage. Stacked on top, the connecting material extending upward from the precast concrete panel formwork of the first stage is fixed to the back surface of the stacked second stage precast concrete panel formwork, and then concrete is placed in the space. And the step of placing the first and second stages before the concrete is completely cured. A step of embedding the other end of the stay, one end of which is attached to the connecting material connecting the recast concrete panel formwork, and fixing the other end by hardening the poured concrete; and After hardening, the connecting material was attached to the back side of the second-stage precast concrete formwork again so that the connecting material protruded from the upper end in the same manner as described above.
Stacking another precast concrete panel formwork at the second stage, fixing it to the connecting material extending upward from the second stage precast concrete formwork, and then placing concrete in the space. A method for constructing a concrete wall by repeating the above steps and pouring concrete to a predetermined height.